m Risø-R-624(J&NT Environmental Science and Technology Department Annual Report 1991
Edited by A. Jensen, V. Gunderson, H. Hansen, G. Gissel Nielsen, O.J. Nielsen and H. Østergård
Risø National Laboratory, Roskilde, Denmark June 1992 Environmental Science and Ris,*^^ Technology Department Annual Report 1991
Edited by A. Jensen, V. Gunderson, H. Hansen, G. Gissel Nielsen, O.J. Nielsen and H. Østergård
Risø National Laboratory, Roskilde, Denmark June 1992 Abstract Selected activities in the Environ mental Science and Technology Department during 1991 are presented. The research approach in the department is predominantly experi mental. The research topics emphasized are in troduced and reviewed in chapters one to seven: 1. Introduction, 2. The Atmosphere, 3. Plant Genetics and Resistance Biology, 4. Plant Nutri tion, S. Geochemistry, 6. Ecology, 7. Other acti vities. The Department's contribution to natio nal and international collaborative research pro grammes is presented together with information about large facilities managed and used by the depanment. Information about the department's education and training activities are included in the annual report along with lists of publications, publications in pr^s, lectures and poster presen tations. Further, names of the scientific and tech nical staff members, Ph.D. students and visitiing scientists are listed.
ISBN 87-550-1806-8 ISSN 0106-2840 ISSN 0906-8090
Grafisk Service, Risø, 1992 Contents
1 Introduction 5 Genetic Resources of Barley with Re j.l Research Objectives 5 sistance to Powdery Mildew 23 \2 The Atmospheric Environment 5 Barley Leaf Stripe 24 1.3 Plant Genetics and Resistance Virulence Gene Products of Barley Biology 5 Powdery Mildew 25 1.4 Plant Nutrition 6 Biocontrol of Barley Powdery 1.5 Geochemistry and Recycling of Indu Mildew 25 strial Waste 6 3.3 Population Biology 25 1.6 Ecology and Mineral Cycling 7 Interaction between GMPs and the En 1.7 The RIMI Field Station 7 vironment 26 1.8 The Experimental Farm, Dyskærgaard 7 Interaction between Crop Plants and 1.9 Organisation 8 Weeds 26 Modelling the Dynamics of Powdery 2 The Atmospheric Environment 9 Mildew Populations 26 2.1 Introduction 9 Taxonomy of Chrysosporium 2.2 The Gas Phase 9 Species 27 CFC Substitutes 9 Halogenated Organic Compound in the 4 Plant Nutrition 28 Troposphere 9 4.1 Nitrogen in Soil and Plants 28 Organonitrogen and Sulphur Atmos Cycling of N from Crop Residues and pheric Transformations 10 Manure 29 Oxidation of Aromatics 12 Nitrogen Accumulation in Winter 2.3 The Liquid Phase 12 and Spring Types of Agricultural 2.4 Field Atmospheric Chemistry 14 Crops 29 Tropospheric Ozone Research 4.2 Root-Microbe Symbioses 30 (TOR) 14 Symbiotic N Fixation 30 Polycyclic Aromatic Hydrocarbons 15 Mycorrhizas and Plant Nutrition 30 Nitrogen Transfer from Legumes to 3 Plant Genetics and Resistance Biology 16 Non-Legumes 31 3.1 Application of Genetic Markers 16 4.3 Effects of Air Pollution on Plants 33 RFLP Map of the Barley Genome 16 Forest Decline and Ammonia 33 Map of the Barley Powdery Mildew Does Ozone Interfere with Carbon Genome 17 Translocation in Wheat? 33 RAPDs of Norway Spruce 78 RAPDs of Cotton 18 5 Chemistry of the Geosphere 34 Quantitative Trait Loci of Barley 18 5.1 Geochemical Modelling 34 Cytogenetics of Barley and Related 5.2 Applied Geochemistry 34 Species 19 Methods 34 In situ Hybridization to Tissue Prepa Terrestrial Geochemistry 34 rations 20 Marine Geochemistry 35 3.2 Mechanisms of Plant-Pathogen Inter 5.3 Geochemical and Applied actions 21 Technology 36 Callose Synthesis in Barley Leaves 21 Marine Environmental Technology 36 Barley Peroxidase 21 Fixation of Heavy Metals in Soil 36 Rapeseed chitinases 22 Wet Oxidation of Organic Material 36 Phenolic Compounds in Barley 5.4 Chemical Analysis 37 Leaves 23 5.5 Syntheses 38
Risø-R-624(EN) 3 5.6 MODECS 38 15 Committee Memberships 77 15 1 National 77 Ecology and Mineral Cycling 39 15.2 International 77 6.1 Ecological Halflives 39 6.2 Influence of Plant Variety on the Root 16 Seminars Organized 78 Uptake of Radiocaesium 42 17 Personnel 79 6.3 Variation in Trace Element Loss Rates 17.1 Scientific Staff 79 from Baltic Mussels 43 17.2 Tehnical Staff 79 6.4 Fish Ecotoxicology 44 17.3 Office Staff 80 6.5 R1MI Field Station 45 17.4 Ph.D. Students 80 6.6 Radioactive Tracers in the Greenland 17.5 M.Sc. Students 80 Sea 46 17.6 Apprentices 81 6.7 Radioecological Cooperation with the former USSR 47 18 Acronvms 82
7 Other Activities 49 7.1 Decontamination Strategies for Urban Areas 49 7.2 Photochemistry and Photophysics 49 7.3 Riso High Dose Reference Laboratory (HDRL) 50
8 Large Facilities 52 8.1 10 MeV Linear Electron Accelerator 52 8.2 Pilot Plant for Metal Extraction 52 8.3 Experimental Farm 52 8.4 Open Top Chamber Facility 52
9 Publications 53 9.1 Refereed Journals and Books 53 9.2 Proceedings (incl. Abstracts) 55 9.3 Research Reports 60 9.4 Other publications 61 9.5 Presentations 63
10 Publications in press 68
11 Education 70 11.1 Ph.D. Theses 70 11.2 M.Sc. Theses 70 11.3 Contribution to Scientific Cources 70
12 Exchange of Scientists 71
13 Cooperative Projects 72
14 Guest Lectures 76
4 Risø-R-624(EN) 1 Introduction 1.1 Research Objectives
The department aspire to develop a sound The department's atmospheric research in scientific basis for future technology and volves three aspects. Firstly, determination of methods in industrial and agricultural produc the sources of air pollution. Secondly, determi tion. Through basic and strategic research, the nation of primary and secondary pollutants in department endeavours to develop new ideas rural areas to assess the effects of atmospheric for industrial and agricultural production, exer processes. Thirdly, laboratory studies of che ting less stress and strain on the environment, mical mechanisms in the gas phase, and in the and with less energy consumption. liquid phase of relevance to atmospheric che mistry. The main research topics are: Atmospheric chemistry influences the clima te, and the deposition of airborne pollutants can Vie atmospheric environment give rise to direct injuries to plants and indirect damage through bio-accumulation. Plant genetics and resistance biology To model and predict changes in the atmos pheric composition, a better understanding of Plant Sutriuon the chemical processes in the atmosphere is needed. In order to make the research results Geochemistry and recycling of industrial operative in the environmental policy making, waste the critical loads need to be established for natural and semi-natural ecosystems. Ecology and mineral cycling
The expert domain of the department con 1.3 Plant Genetics and Resistance tains a wide range of subjects including atmos Biology pheric chemistry, chemical reactivity, geoche mistry, biogcochemistry, gcochcmical model In this field of research, the department aims to ling, hydrochemistry. analytical chemistry, develop the scientific basis for breeding crop organic synthesis, marine and terrestrial ecolo plants with new and improved resistance to di gy, radioccology. trace metal ecology, plant seases and with improved nutrient efficiency. nutrition, biological interactions, plant molecu Growing plants, highly resistant to diseases lar biology, plant pathogens, plant genetics and with less nutrient demand, will reduce a num cytogenetics, and plant breeding. ber of environmental problems related to high yield plant production. Exploitation of genetic variability, related to 1.2 The Atmospheric Environment traits of economic and environmental import ance in crop improvement, can be greatly faci The atmospheric research aims to establish a litated by the use of marker-assisted selection; solid scientific basis for rational legislative a large part of the research effort within plant measure to reduce the industrial impact on the biology and genetics is devoted to the applica atmosphere of air pollution. tion of genetic markers. The research relics on The research includes basic atmospheric che the command of a number of techniques such mistry, gas kinetics, transport and dispersion of as RFLP, RAPD, PCR, genetic analysis of air pollutants, especially nitrogen compounds quantitative traits, cytogenetic techniques, en and carbohydrates, VOCs. PANs. PAHs. CFCs, zyme electrophoresis, in situ hybridization and HCFCs and MFCs. in vitro culture.
Riso-R-624(EN) 5 An understanding of the interaction between condl). studies of the interaction between VA- plant species, as well as the interaction between mychorrhiza. plant roots and the rhizosphere. plants and pathogens, can be enhanced by Thirdly, studies on turn-over of nitrogen from identification of changes in genetic variability crop residues and farmyard manure by use of under different environmental conditions. Three I5N-Iabcllcd plant material and farmyard different aspects of plant pathogen interactions manure. Fourthly, biological transfer of nitro are studied. First, chemical defence compounds gen from legumes to non-legumes. Fifthly, the such as callose. peroxidase and chitinase are effect of air pollution with ammonia, especially studied in barley and rapeseed together with on Norway spruce. various phenolic compounds in barley. Second, The research is essential to the future devel genetic resources of species- specific resistance opment of new plant production techniques in barley to powdery mildew- and leaf stripe based on biological fixed nitrogen, and with disease are studied. Third, we try to elucidate highly effective assimilation and recycling of the very specific interaction based on gene-to- nutrients in order to reduce the possibility for gene recognition in the barley powdery mildew- loss of plant nutrients due to surface run off. system. losses of nutrients to the atmosphere or leakage In population biology, experiments and theo to the ground water. retical studies of interactions between popula tions are important in understanding the sy stems. The research is devoted to interactions 1.5 Geochemistry and Recycling of between crop plants and weeds, and between Industrial Waste crop plants and their pathogens. The possible exchange of genes between related species and In this area, the department has contributed to the competitive abilities of crop plants are the scientific development of the wet oxidation studied together with the risk of gene flow technique. New methods are developed for the from genetically modified cultivated plants into conditioning and treatment of soil, sludge, wild natural relatives and the effect of new sewage and other waste products from indu genes transferred to natural plants. This type of strial productions contaminated with heavy research is needed to evaluate the risk to the metals. environment from transgenic varieties. Existing toxic waste deposits have created severe environmental problems in industrialized countries, and the department aims to develop 1.4 Plant Nutrition methods to repress the uncontrolled release of toxic material from waste deposits. The aim of the plant nutrition research is to In ccochcmical modelling, the JENSEN pro provide a solid scientific basis for a better gram has successfully been applied to predict understanding of root-microbe symbiosis in the possible gcochcmical transformations to be relation to carbon, nitrogen and phosphorus, expected, when foreign minerals are added to and to provide scientific information about the polluted waters. The research also aims to turn-over of organic nitrogen. model the migration of heavy metals and nu The research emphasizes biological, physio trients, and predicts the fate of deposits in logical, biochemical, chemical and physical geological structures and in soils. processes involved in the transfer of plant In marine geochemistry, rare and precious nutrients, especially nitrogen and phosphorus metals were studied in marine sediments, as through the Soil-Plant-Air-Continuum. well as the fciiomangancse phase, from the The department's plant nutrition research Pacific. Fcrromangancsc crusts and nodules involves five aspects. from New Zealand were analyzed for rare Firstly, research on symbiotic nitrogen fixa elements. Radiometric methods for inspection tion, which highlights the exchange of com of the sea floor and a new radiometric sonde pounds between the host plant and the micro- arc being developed for exploring marine sedi symbiont across the membrane interface. Sc- ment resources.
6 Risø-R-624(EN) In analytical chemistry, an electrothermal accident, and Tc from Scllafiekl and La vaporisation unit has been linked to the Hague. ICP.'MS. The instrumentation has been ex The Ecology section also develops strategies panded with new HPLC equipment and the in and techniques for decontaminating areas con stallation of a new GC MS; a HPLC MS is taminated by radioactivity. Different strategies planned in 1992. New analytical methods for and techniques have been tested in Gavle. trace metal analysis and stable isotope analysis Sweden and a 'skim and burial" plough has are being developed. been developed for burial of the S cm con The department is involved in several com taminated top-layer in agricultural areas. mercial organic synthetic projects, ranging from The research depends on concepts and tech the preparation of isotoptcally labelled com niques from radio-ecology. Concepts of envi pounds, to the attachment of supramolecular ronmental dosimetry and critical loads for units to both natural macromolecules and poly ecosystems are developed together with tech mer surfaces. At present the group is synthe- niques for evaluating ecotoxicology in marine sising catalytically active metal complexes, and terrestrial ecosystems. bonded to elcctroconducting organic polymers.
1.7 The RIMI Field Station 1.6 Ecology and Mineral Cycling Riso's Integrated Environmental Project (RIMI) Ecological and mineral cycling research aims is an interdisciplinary projet studying pathways, to improve the scientific basis and understand processes and effects on terrestrial ecosystems ing of the impacts of environmental pollution of nitrogen compounds derived from human on marine and terrestrial ecosystems with activities. emphasise on natural and semi-natural ecosy RIMI is managed by the Ecology section and stems. Further, the research aims to establish involves scientists from the Environmental better knowledge about transport and the faith Science and Technology Department, as well as of pollutants by use of radionuclides and scientists from the Meteorology and Wind traccmctal techniques. Energy Department and the Optics and Fluid Ecological halflivcs of radioactive contami Dynamics Department at Riso. nation of terrestrial environments by fallout The RIMI station serves as a reference sta from the nuclear weapons testing in the atmos tion for air pollution monitoring in Copenhagen phere and regional fallout from the Chernobyl by the National Environmental Research Insti accident arc studied in the Danish and Farocsc tute. The RIMI station is also used in the Da environment. nish ELROTRACH-TOR project. The influence of plant variety on root uptake of radiocacsium is studied because the long term consequence for agricultural ecosystems 1.8 The Experimental Farm, of radioactive contamination depends on the Dyskærgaard transfer of radionuclides from the soils via roots to the above ground biomass. Dyskærgaard has 120 hectares of arable land, Radioactive tracer techniques arc used in and is managed by the Plant Biology section. projects on metal toxicity to fish and Baltic The experimental farm is partly used for scien mussels as bioindicators for marine monitoring tific field experiments, and partly for grain and programmes for radionuclides and heavy beef production. metals. During the growing season, a herd of Here The Greenland Sea project aims to explain ford cattle graze the sea-shore meadows and the role of the Greenland Sea in the World salt marshes along Roskilde Fjord for nature Ocean Circulation making use of radioactive management purposes. tracers ,37Cs and ,34Cs from the Chernobyl
Riso-R-624 1.9 Organisation The Environmental Science and Technology Department was formed during the reorganiza tion of Riso National Laboratory in March 1990. and includes the former Agricultural Research Department, the former Chemistry Department in part, and the Ecology section from the former Ecology and Health Physics Department. The Environmental Science and Technology Department includes approximately 135 scien tific and technical staff members, and the de partment is organized into four sections with Di Aiu? Jensen as Department Head. 1. Ecology Section. Head: Dr Asker Aarkrog 2. Chemical Reactivity Section. Head: Dr Ole John Sielsen 3. Chemistry Section. Head: Dr Vagn Gundersen 4. Plant Biology Section. Head of Plant Nutrition: Dr Gunnar Gissel Sielsen Head of Plant Genetics and Resistance Bio logy: Dr Hanne Østergård. 8 Rirø-R-624(EN) 2. The Atmospheric Environment 2.1 Introduction dation of these compounds in the lower atmos phere before they reach the stratosphere. The effect of human activities on the global at CHjCHF, (HFC-152a) and CHC1XF, mosphere has become evident during the last (HCFC-123) are two important compounds decades. For example, the tropospheric ozone which have been proposed as alternatives to concentrations have increased by a factor of CFCs. Atmospheric oxidation of these com three in remote areas and photochemical smog pounds in the lower atmosphere is initiated by can be observed very long distances away from OH radical attack to generate the corresponding populated areas. An understanding of atmos halogenatcd alkyl radicals: pheric changes requires a detailed characteri CHjCHF, + OH -> CHjCFVCHXHF, • H,0 zation of the composition of the atmosphere. The department's atmospheric research has CHClXFj + OH -> COjCFj • H,0 three aspects. The first is the determination of Considering the importance of these reac the sources of air pollutants. The second is the tions, it is surprising that, when this study was determination of primary and secondary pollu initiated, there were only a few studies pub tants in rural areas to assess the influence of lished on the reaction of OH radicals with atmospheric processes. The third is the labora these compounds. tory investigation of chemical mechanisms in The rate constants for the reaction of OH the gas and liquid phase, relevant to atmos radicals witn CHjCHF, (HFC-152a) and pheric chemistry. CHCUCFj (HCFC-123) were determined over the temperature range 295-388 K. All the measurements of OH rate constants were 2.2 The Gas Phase carried out using pulse radiolysis combined with kinetic spectroscopy and the results have CFC Substitutes been published (Nielsen. 9.1). The loss of stratospheric ozone over the An Halogcnafed Organic Compound in the Tro tarctic in the early austral spring, stresses the posphere importance of the atmospheric chemistry of halogenatcd compounds. Field observations, 1991 was the second year of a STEP project combined with many experimental measure involving 9 European laboratories concerned ments of the kinetics and mechanisms of the with the kinetics and mechanisms of oxidation atmospheric reactions of key halogen-contain of chlorine - and bromine - containing com ing species, show that the release of man-made pounds, under atmospheric conditions. It is the chlorofluorocarbons significantly perturbs the aim of this study to determine the troposphcric earth's atmosphere. These observations confirm sinks for these halogenated compounds in order the hypothesis of Rowland and Molina (1974), to provide a basis for the calculation of the that release of large amounts of these com ozone depletion potential of released halo- pounds would significantly reduce the levels of genated species. Pat of this work, concerning stratospheric ozone. This has led to an interna the spectra and kinetics of peroxy radicals, is tional agreement to stop CFC production and to being performed in collaboration with Dr. T. find replacement compounds. Hydrochlorofluo- Wallington. Ford Motor Co., USA. Several rocarbons (HCFCs) and hydrofluorocarbons CFC replacement compounds were investi (HFCs) are likely CFC substitutes for a number gated. The work on the pcroxy radicals of of uses. HCFCs and HFCs contain one or more HCFC-141b (CFCI:CH,0:) and HCFC-142b hydrogen atoms, thereby providing a point of (CF:CICH;0:) was finished and published attack for the hydroxy! radicals to initiate oxi- (Wallington and Nielsen a, 9.1). Riso-R-624(EN) 9 HFC-134* (1.1.1.2-tctrafluorocthanc) is one lion rates. It has been suggested that one of the of the potential substitutes for CFC-12 in air- dominant sources of bromine in the atmosphere conditioning systems. Following release. HFC- is methyl bromide. CH,Br. Data also suggest 134a will react with OH radicals in the lower that the major part of emitted CH3Br is of atmosphere to produce an alkyl radical which anthropogenic origin. Because the absorption will, in turn, react with O, to give a peroxy spectrum of CH,Br has insignificant overlap radical; with the region of the tropospheric solar flux. CHjBr is mostly removed from the atmosphere CFjCFH, • OH -> CFjCFH + H 0 : by reaction with OH radicals. Atmospheric CFjCFH • O, + M -> CF,CFHO; + M oxidation of methyl bromide in the lower at The atmospheric fate of the peroxy radical mosphere is initiated by OH radical attack to CFjCFHO, is uncertain. Recently, concern has generate bromomethyl peroxy radicals. The been expressed that this peroxy radical would products of the oxidation of methyl bromide react with NO to produce an alkoxy radical, then depends on the fate of the CH:Br02 radi possibly leading to the formation of triftuoro- cals. acetic acid. Soil bacteria might then metabolize The pulse radiolysis technique was used to trifluoroacctic acid to produce monofluoroace- measure the UV absorption spectra and self- tic acid - a potent mammalian toxin. To reaction kinetics of the CH,Br and CH:BrO, address this issue, the atmospheric chemistry of radicals. As an aid in the interpretation of the the peroxy radical derived from HFC- 134a. kinetic data, additional experiments were per needs to be understood. formed to investigate the products of the self- Most kinetic studies of peroxy radicals rely reaction of CH:BrO: radicals using an FTIR on monitoring their strong absorption in the spectrometer coupled to an atmospheric reactor UV. Hence, the first step was to investigate the (at Ford Motor Co.). Both the recorded spec trum (see figure 2.1.) and the obtained self- UV absorption spectrum of CF,CFHO:. and then to measure the kinetics of the reaction of reaction rate constant were very surprising. The CFjCFHO, with NO. observed rate of the self-reaction of bromom The measured cross section at 220 nm was: ethyl peroxy radicals in the present work is °CF3CHFo:<~fJ nm) = (5.34 s I.08)x 10"" cm: extremely rapid; i.e.. approximately 100 times mol"1. The rate constant for the reaction of faster than that of CH}0:. and 10 times fastCT CF3CFHO2 radicals with NO was then deter than those of CH:FO:. and CHXIO,. While mined to be (1.28 £ 0.36)x 10"" cm' mol'1 s- the exact mechanism by which this occurs re '. As pan of this work, the rate constant for the mains uncertain, the enhanced reactivity of reaction of F atoms with CFjCFH, was bromomethyl peroxy radicals presumably re measured and found to be (3.6 2 0.9).\ 10~i: flects a stabilization of the transition state by cm3 molecules"1 s"1 at 298K. The results have the presence of the bromine atom. Further been published (Wallington and Nielsen b. 9.1). studies on the temperature and pressure depe ndence of this reaction are needed. The results Bromine is also engaged in catalytic destruc obtained so far have been published (Nielsen et tion of ozone in a similar cycle to that of chlo al. a. 9.1). rine. Indeed on a per molecule basis, bromine is a more efficient catalyst than chlorine in removing ozone. Little is known about ;he Organonitrogen and Sulphur Atmospheric sources of different bromine compounds. Natu Transformations ral sources include biological activity in the oceans and volcanic activity. Bromine-con In the final year of our four-year CEC-fundcd taining compounds are used for a variety of collaboration with University College Dublin, purposes; fumigants. fire-fighting agents, ana we have continued our investigations of the esthetics, etc. The atmospheric lifetimes of the reactions of OH radicals and CI atoms with a various bromine compounds differ substantial wide variety of compounds. Two series of ly, because of differences in rates of reaction organ-iniirogcn compounds were investigated: with hydroxy! radicals and photolyiic dcslruc- n-alkvl nitrates and n-alkyl nitrites. 10 Riso-R-624(EN) 800 CH-BrO, (This work) / \ d 600 CH.C10_ (NIST) o 2 *w2 o O O 8 CH N ; o 3°2 ("recom") 6 400 o \ - 200 x CH.FCL (This Lab.p \ t> ^ o :£L 200 250 300 350 Wavelength, nm Figure 2.1. Tlie observed UV-absorption spectrum of CH2Br02 obtained at Risø compared with those of CHs02 (recommended), CH2ClO)2 (from Sational Institute of Standrads and Technology) and CH2F02 (also from Risø). The atmospheric lifetimes of the n-alkyl constant data determined in this work. Assum nitrates, due to loss by reaction with OH rad ing a tropospheric concentration of 1 x 106 icals, can be calculated from the rate constant molecules cm"3 for OH radicals in moderately data determined . . this study. Assuming a tro- polluted atmospheres, the rate constant data 6 pospheric concentration of 1 x 10 molecules give lifetimes of about 30 days for CH3ONO to 3 cm" for the OH radical, the relatively low around 2 days for n-C5HnONO. A photodis- reactivities of the nitrates give lifetimes in the sociative lifetime for CH3ONO of approxima range of 30 days for CH3ON02 to 3 days for tely 2 min was calculated. The lifetime is n-C5HnONO:. An estimate of the photodisso- almost independent of altitude, since the ab ciative lifetime for CH3ON02 of approximately sorption spectrum of CH3ONO extends into the 5 days, based on the removal by reaction with visible region, where the solar flux intensities OH radicals, has been reported in the lower are strong and nearly constant with altitude. troposphere. Absorption cross-section data This estimate is based on a quantum yield for were used in these calculations. This estimate photodecomposition of unity and is hence a is based on the quantum yield for photo-de lower limit. The available kinetic and composition of unity and is hence a lower photochemical data indicate thaf the atmosphe limit. Thus the alkyl nitrates may act as tem ric lifetimes of alkyl nitrites will be dominated porary sinks for nitrogen in the troposphere and by their photolysis rates and that they will be become important in long-range transport of rapidly removed during daylight hours (Nielsen odd nitrogen (Nielsen et al. b, 9.1). et al. c, 9.1). In the case of the n-alkyl nitrites, the atmos Recently, much interest has centred on the pheric lifetimes, due to loss by reaction with role of natural organic sulphur compounds in OH radicals, can be estimated from the rate atmospheric sulphur chemistry. The CH3S Risø-R-624(EN) 11 radical, and possibly the CH:SH radical to a much more slowly with oxygen, as in the case lesser extent, are important intermediates in the of HO-C6H6. oxidation of the naturally incurring sulphur species in the atmosphere. In collaboration with Dr. C. Anastasi's group at University of York 2.3 The Liquid Phase (UK) we have investigated the UV absorption spectra of CH3S and CH2SH radicals. The Ozone is an important species in the aqueous results have been published (Anastasi et al. oxidation processes in the atmosphere. It is, 9.1). therefore, important to understand the 03 de composition mechanism in the aqueous phase. Oxidation of Aromatics This study has shown that the initiation reac tion in acidic solution is different from that in The tropospheric oxidation of benzene and alkaline solution. In acidic solution, the initia other aromatics is initiated by reactions with tion of the chain decomposition of ozone must OH radicals. This has been studied in an EEC- be ascribed to the ozone dissociation/recombi project (STEP-0007-C). Benzene reacts rever- nation reaction. The creation of chain-propa sibly giving an adduct OH + C6H6 = HO- gating radicals (OH and H02) probably pro C6H6. In order to study the subsequent reac ceeds via a reaction with water in a tions, we recorded the UV-absorption spectrum heterogenous process on the surface of the of HO-C6H6 which has a maximum at 280 nm. reaction vessel. The results from a study on the The kinetics of the reaction HO-C6H6 + 02 — effect of 03 concentration, oxygen, pH, tempe > products were studied by monitoring the rature, vis-light and isotopic oxygen exchange transient absorption of HO-C6H6 at 280 nm in (Sehested ei al. 9.1), clearly demonstrate that the presence of varying amounts of oxygen. the 03 decomposition is associated with the The reaction is very slow and we have esti dissociation of the 03 molecule. To obtain a mated an upper limit for the rate constant of better understanding of the initiation process, 14 3 1 k(HO-C6H6 + 0:)m„ = 2 x 10" cm mol' s" acetic acid was employed as a radical scaven 1 at T = 298 K. The reaction with NO, was ger. In the study of concentration effects, pH, found to be much faster, k(HO-C6H6 + N02) = temperature and H202 formation and consump n 3 1 1 2.5 x 10" cm mol" s" . The reaction with tion, the rate of the initiation reaction was oxygen, however, is still thought to be the most determined to k = 3.0 x 10~6s_1at 31 °C and important process in the tropospheric oxidation the activation energy to 82.5 kJ mol"1. From of benzene. Work is in progress to determine the same system, a rate constant for the reac the reaction products, and the reaction HO- tion of ozone with undissociated hydrogen 3 1 C6H6 + 02 --> H02 + <"6H5OH would appear peroxide was found to be 0.0065 dm mol" to be the most important channel under atmos s"1 at 31 CC. Further study of the reaction of pheric conditions. Similar experimental work 03 with H202 indicates that both initiation and has been carried out with toluene, where the termination of the radical chain are surface reaction with hydroxy! radicals was found to reactions. proceed via two different channels, (a) HO + The rates of the oxidation reactions of fer C H CH —> H,0 + C H 12 Risø~R-624(EN) The S04~ and N03 radicals are important MPa. Computer simulations of the reaction oxidizing agents in the aqueous phase of the mechanism were performed to determine the atmosphere. S04" is an intermediate in the rate constants and activation energies. An 2+ radical chain oxidation of S(IV) to S(VI) and at article on Fe + H202 has been submitted for night-time, N03 is the main oxidative radical publication. This work is carried out in colla in the gas phase and may diffuse into the boration with Studsvik Energiteknik AB, aqueous phase. The S04~ is known to react Sweden. with N03" to form N03 with a rather low rate, Kinetics of reaction of primary water radicals 4 k = 5 x 10 M s"\ but our experiments show ejq, H, OH, and O" with: 2-pyridinecarboxy- that it reacts with HN03 at a much higher rate, lic acid, 4-pyridinecarbcxylic acid, ^,6-pyridi- also forming N03. On the other hand, N03 nedicarboxylic acid, 3,5-pyridinedicarboxylic reacts with HS04" reforming the S04" radical acid, as well as spectral and kinetic character and an equilibrium between S04" and N03 is istics of transients thus formed, were obtained obtained. From experiments with mixtures of in a pulse radiolysis study (Solar et al. 9.1). An H2S04 and HN03 an equilibrium constant of interesting feature, observed only in acid solu K = 1.3 x 103 was measured. The forward tions, was the formation of two distinct pro reaction (S04" + HN03) is of the order of 1 x ducts in reaction with the H atom, namely H- 107 dm3 mol"1 s"1, and an article has been adduct to the pyridine ring and pyridynyl radi submitted for publication. cal. In the case of 3,5-pyridinedicarboxylic The rate constant of the reaction S04" + OH acid, an intramolecular transformation of the was determined in photolysis and radiolysis of ring adduct into the corresponding pyridmyl 10 3 1 S04F" solutions, k = l.OxlO dm moV s"\ radical was observed. (Waning ei a\. 9.1). Several other rate cons This investigation was folloved by a similar tants for S04" reactions with H, 02~, HO:. study of methyl substituted pyridines: 3-me- S:08~~, and S:Os"" reactions with H and thylpyridine, 3,5-dimethylpyridine, 2,6-dime- 02"/H02 were determined, employing our high thylpyridine and 2,4,6-trimethylpyridine. It was pressure technique. Also using high pressures found that the reaction kinetics, as well as (150 atm), rate constants for the N03 radical spectra of the transients, are dependent of the reactions with N0;. H0:. H202 and formalde protonation of ring nitrogen. The pKa values of hyde were measured. OH-adducts were found. As the absorption In the photolysis of an aqueous C103" solu spectra of the respective transients fall beyond tion, it is found that the primary process the accessible range, the question as to the occurrence and extent of direct H-abstraction C103" ^ CIO" + 02 is the result of a cage-back reaction of the primary process from the methyl groups remains unresolved. This project is carried out in collaboration with C103" ™ CIO-, + O". The ratio of the yields the University of Vienna, Austria. of CIO" and Cl6 " in the reaction C10 + O", 3 2 Pulse radiolysis studies of intramolecular determined in y-radiolysis of C10 solutions at 2 electron transfer in proline-bridged peptides varying pH, equals the ratio between the quan Trp(Pro)nTyr was extended for n=4 and n=5 tum yield of 0 formation and the quantum 2 with the tryptophan terminal in both L- and yield of C10 " returning to the ground state 3 D- form. Also cyclic peptides, with proline after photolysis of C10 ". This is taken as 3 and glycine units between tryptophan and evidence for the cage-back reaction (Klåning tyrosine, were studied. The rate constants were and Sehested, 9.1). This work is carried out in measured over a 10-55 °C range and activation collaboration with Århus University. parameters obtained. Significant influence of The work on high-temperature high-pressure pH and optical isomerism on the intramolecular aqueous radical chemistry continues by study electron transfer rate was found in these sy ing the reactions H + OH, OH + OH, ea"q + stems. OH, e; + H, e " + H 0 and Fe:+ + H 0 . q a q 2 2 2 2 The study of intramolecular electron transfer The purpose is to determine the rate constants, in HEW-lysozyme continued, in order to activation energies and reaction mechanism at a establish which of the Trp/Tyr pairs is respon- temperature of 300 6C and pressures up to 15 Riso-R-624(EN) 13 sible for the azide radical-induced Trp/N* -» ject focusses on the composition of nitrogen Tyr/O* transformation. For this purpose, the compounds. effect of temperature, substrate (triacetylochi- Thus, the composition of nitrogen com totriose) binding and conversion of particular pounds was studied in detail during the period tryptophan (Trp-62) by ozonation were August 15-20. Some of the compounds were applied. The obtained results indicate that Trp- determined by more than one method, NO,, 62 and Tyr-53 are mainly involved. This work HNO, and particulate N03". Satisfactory is carried out in collaboration with the Polish agreements were achieved. HNO, wis not Academy of Sciences. detected (< 0.03 u,g N/m3). PAN was evaluated by means of the empirical relationship estab lished earlier. 3 2.4 Field Atmospheric Chemistry PAN <>g N/m ) = 0.58 * ((03(ppb) - 30)/15), and PPN = 0.2 * PAN. Tropospheric Ozone Research (TOR) The first part of the period was at the end of a long and dry spell with elevated concentra The DCAR-TOR (Danish Center of Atmos tions of air pollutants. An occluded front from pheric Research) project is a part of the Euro the north-west passed on August 16th, fol pean joint project EUROTRAC-TOR and is lowed by a second front in the late evening of performed in collaboration between the Section August 17th. The average concentration of total of Chemistry and the National Environmental NOv (including particulate N03") was 4.4 jxg 3 Research Institute. The project coordination is N.'m . The composition of NOy was: NO (0.4 3 carried out by the Chemistry Section. MS N/m - 8%), NO, (2.5 - 57%), HN03 (0.1 The Danish TOR measurements began in - 3%). N03" (0.7 -~15%), PAN (0.1 - 2%), 1991 and include continuous measurements of PPN (0.03 - 0.7%). and the residual amount NO-., SO, and 03 with differential optical ab (organic nitrates) (0.5 - 12%). sorption spectroscopy (DOAS), 03 (UV-ab- The residual amount was highest in the oo 00 sorption monitor), NO and NOv (chemilumini- measuring periods 15:l8 -16:06 , 16:06°°- scense monitor). H20, and aerosols (metals. 16:18"°, and 20:06^-20:18°° (Fig. 2.2.). Also a S04"", CI"). In addition, measurements of residual amount was observed in the measuring vapour phase HNO, and HN03 and particulate periods lT.WP-n-.lg", 18:18°°-19:06°°, nitrate are made in short periods. 19:06"°-19:18°° and 19:18°°-20:0600, although In 1992, development of methods for mea these amounts are too small to be significant. surements of VOC (volatile organic com Interestingly, the residual amount was zero or pounds) and organic peroxides is planned and sligiiiiy negative in the measuring periods coriin'.ous measurements of peroxyaceiy! le-lS^-ll-M00, n:lB°°-\S:06°° and 18:06°°- nit.a'e (PAN) and peroxypropionyl nitrate 18:18°°. This seems reasonable, as the air pol (PPN) will begin. lution was low in these periods and the air Photochemical air pollution is closely linked chemistry diminished, due to clean air masses with the occurrence of nitrogen oxides. Nitro following the cold fronts. These preliminary gen oxides are important precursors for the results suggest the possibility of the presence formation of photochemical air pollution of significant amounts of organic nitrates in (Nielsen and Lohse, 9.4), and PAN and PPN rural areas of Denmark. are two important photochemical oxidants. It A comparison of the results of volatile NOy has also been found that nitric acid and par with those of NO, (DOAS) for August and ticulate nitrate are the final products of the September, confirms the presence of substantial oxidation of nitrogen oxides, contributing to amounts of nitrogen oxides in excess of NO acid rain and nitrogen eutrophication. The and N02, as NO, is less than the difference formation of sulfuric acid, nitric acid and between NOy and NO: particulate nitrate is promoted by photochemi NO, (DOAS) (ppb) = 0.53 * (NOy - NO) cal oxidants. Therefore, the Danish TOR pro- (ppb) + 0.55, (r = 0.58; p < 0.001). 14 Riso-R-624(EN) Composition of Total NOy (ugN/m3) 1518 leoe 1618 1706 1718 1806 1818 1906 1918 2006 start_time 0 HO Moniter D N02.KI SS HN03;NaOHDE CD N03;KaOHDe 0 PMI S PPN D Residual Figure 2.2. Vie composition of atmospheric nitrogen compounds at Lille Valby in the period 15-20 August. Polycyclic Aromatic Hydrocarbons Air pollution by PAH (polycyclic aromatic Within DCAR, a traffic PAH project has hydrocarbons) has been investigated for many been planned and organized to start in January years, one reason being that several PAH are 1992. The project will provide PAH data from carcinogenic. The atmospheric chemistry of different locations in the initial phase of the PAH has been studied in detail. Analytical introduction of catalyst-equipped cars. Another methods were developed, as well as methods aim of the project, is to determine the contri for determining the source contributions. An butions from gasoline- and diesel-driven cars, article concerning this is in press. respectively. Risø-R-624(EN) 15 3 Plant Genetics and Resistance Biology Methods for identification, characterization and lable. Notably the random amplified polymor quantification of genetic variability are essen phic DNA (RAPD) technique has given pro tial to many basic and applied research pro mising results. grammes in agricultural and environmental In particular, these new methods may help in sciences. Exploitation of genetic variability, •nderstanding the genetic basis of many agro related to traits of economical and environ nomical traits which are of a quantitative mental importance in crop improvement, can be nature ar.i gc vented by the interaction of many greatly facilitated by the use of marker-assisted Quantitative Trait Loci (QTLs) impossible to selection. The understanding of interaction assay independently. between species of plants, as well as between plants and pathogens, can be greatly facilitated RFLP Map of the Barley Genome by identification of changes in genetic variabi lity under different environmental conditions. An RFLP linkage map of the barley genome For these purposes, a large part of our research was constructed using chromosome doubled is devoted to the establishment of genetic mar haploid lines from a cross between the winter kers, construction of genetic/physical linkage barley variety ('Vogclsanger Gold") and the maps, and analysis of genetic diversity in po spring variety ('Alf). This was assisted by pulations. With these tools, the mechanisms of international cooperation and the exchange of plant-pathogen interactions are studied with the markers. The map and markers provided the aim of describing those gene products which basis for a cooperative project with the Danish arc important for resistance or virulence. Fur barley breeders. ther, the evolutionary processes imposed by The Laevigatum resistar.: •; gene against interactions between crop plants and wild plant bariey powdery mildew, has been used in bar species or pathogens are studied. ley breeding for many years (H.P. Jensen et al., 9.2) and is now localized to chromosome 2. This previously unlegalized resistance locus has 3.1 Application of Genetic been given the name MILa. The locus was Markers found to belong to a linkage group spanning 119 cM. This group consists of the v (2 rowed/6 rowed) marker and 10 RFLP markers A genetic marker is a trait 1) that is relatively bordered by 2 peroxidase loci. The chromo easy to score, 2) by which individuals can be somal location was determined by 1) hybri grouped into a small number of classes and 3) dization of RFLP markers to the wheatbarley for which the inheritance is well-established. addition lines, 2) linkage to previously locali The trait may be visible as for morphological zed RFLP markers from other laboratories, and markers, or may need biochemical assays as in 3) linkage to the 2 rowed/6 rowed character. the case of isoenzyme and DNA markers and One RFLP marker was found to link with chromosome bands. New molecular methods \.5% recombination to the MILA gene provid for the detection of polymorphisms and their ing a very efficient marker for this gene. Based exploitation, represents one of the most signifi on previous repoits, it is also highly likely that cant recent developments in plant biology. The genes conditioning barley leaf stripe resistance, RFLP (Restriction Fragment Length Polymor and resistance to the cereal cyst nematode, phism) technique, already in use for some reside in this region of chromosome 2 (fig years, is very laborious and requires the hand 3.1.1). ling of genetically modified organisms and radioactive nucleotides. With the development The development of an RFLP-based linkage of polymerase chain technology (PCR).new and map of the barley genome opens up the possi safer mapping techniques have become avai- bility of carrying out marker-assisted selection. 16 Risø-R-624(EN) barley breeding. Currently, RFLP analysis of the first backcross generation individuals, pBHG-301 derived from a cross between a primitive Ethiopian line, containing a potentially new resistance gene to barley powdery mildew, and 17 a modern variety is being undertaken (Petersen, 9.2). On the basis of this analysis, the variation Xrisl8 in the content of recurrent parent genes in the population will be estimated. 22 RFLP markers were employed in determi ning the genetic variability in a number of barley varieties, such as landraces from Ethio pia and Nepal, and Hordeum spontaneum. Preliminary results indicate that the landraces 10 ^ MWG503 and H.sponianeum display greater variability in this respect than the cultivated lines and this is Rh«2. gene for in accordance with most results from other -'• resistance towards 29 cereal cyst nematode marker studies. Map of the Barley Powdery Mildew Genome '•/• The barley powdery mildew fungal genome has A' Xris21 Xrisll been analyzed using RFLP markers. A linkage map consisting of 50 RFLP loci and 5 virulen 11 "p ce loci has been constructed. However, most of xMSUIl the RFLP markers were represented at more A] w • .ru ——, Genuene folor resistancresisia e than one chromosomal site. Thus localization 7 AriS^S D towards barley ——' lealosff strip»trine of single copy sequences failed with this 6 Xris45a method. In order to obtain markers suitable as 8 y CMWG660 startpoints for chromosome walking towards specific virulence loci, other markers were * 1: Xns16 required. The RAPD marker system has been V Prx7 ';: ' successfully adapted to the fungal system, and '; ' '» DNA extraction methods, to obtain pure DNA from small amounts of fungal spores, have F/g. 5.7.7. Linkage map of barley chromosome been developed. The RAPD markers found 2 based on RFLP markers. Tlie map includes were reproducible and segregated according to the previously non-localized powdery mildew Mendelian expectation in off spring lines. On resistance locus Mia. Tlie likely positions of the basis of these results, a M.Sc. thesis has resistance genes towards cereal cyst nematode been written (Justesen, 9.4). Collaboration on race 2 (R)ia2) and for resistance towards bar the mapping of RAPD markers was initiated ley leaf stripe are indicated. with a group in Zurich. The genome has also been characterized In plant breeding, introduction of resistance cytologically, as well as by pulse field gel genes from primitive landraces of barley has electrophoresis. Seven or 8 chromosomes were been inhibited by the carryover of unfavourable identified cytologically (Fig. 3.1.2), but only 5 genetic background material. Early and effi bands could be resolved by electrophoresis cient selection for the desirable genetic back (Borbye et al., 10). The bands were of high ground will facilitate the use of wide crosses in molecular weight. Riso-R-624(EN) 17 .\ ». '/ F/g. 3.1.2. Light microscopy of mycelia from E. graminis fsp. hordei with orcein-stained DSA (Bar indicates 10 fim). Tlie cell at somatic metaphase shows the presence of seven to eight chromosomes. Two of the chromosomes are often connected. Vie shape of the chromosomes varies from triangular and rodlike to circular. Tlie nucleolus is very persistent and therefore hiding the nucleolus-forming chromosome. We establish the chromosome number of the barley powdery milde*' fungus to be at least n = 7. RAPDs of Norway Spruce RAPDs of Cotton With the aim of developing molecular genetic To help with the improvement of cotton breed methods suitable for "high density genome ing in India and Thailand, a project aimed at mapping" in Norway spruce, this project was transferring biotechnological experience to initiated in collaboration with the Arboretum, these countries was initiated in 1991 in colla RVAU, in 1991. The goal is to produce a satu boration with a Danish textile merchant, and rated genome map of about 200 gene loci. local scientists and breeders. With this map, a search of linkage to quantita Preliminary experiments were carried out on tive trait loci, important for the breeding objec material from Indian and Thai cotton plants tives in Norway spruce, can begin. This field grown in a greenhouse. A method has been of research is considered to be an important established to extract DNA from cotton leaves, component in the long-term breeding strategy although this method still needs optimization. of Norway spruce, since early selection, based The cotton DNA was purified and successful on markers for lpte expressed characters in the restriction enzyme digestion was performed. long living trees, will speed up the breeding The RAPD technique was used on cotton DNA programmes. and the band patterns obtained were reprodu Up to now, DNA extraction of needles, buds, cible. The next step is to search for polymor germinating embryos and the seed endosperm phisms using RAPDs as molecular markers. has been performed and optimized. It has been demonstrated that the RAPD technique is Quantitative Trait Loci of Barley usable on DNA extracts from all four types of tissue mentioned. The results are reproducible Most of the important characters of agricultural but the process requires further refinements. A crop plants show continuous variation and are promising degree of polymorphism was ob usually assumed to be controlled by many served. genes. Little is known about the Quantitative 18 Risø-R-624(EN) Trait Loci (QTL) which underlie continuous positions. This was attempted through hybridi variation. Mcndelian markers, in particular zation of barley with rye, carrying accessory isoenzyme and RFLP markers, were used to chromosomes (B chromosomes) that are known detect associations with quantitative traits in to influence chiasma localization. Eighty-six barley (Kjarr et aL, 9.1. J Jensen, et al, 9.2). crossing attempts resulted in five plants. The A field trial, with two nitrogen levels and application of Giemsa C-banding revealed that two replicates, was carried out in 1991 with 79 two normal green plants were haploids of bar chromosome-doubled haploid (DH) lines from ley and three necrotic plants were barley x rye a cross between the varieties (Tystofte Prenti hybrids with one or two B chromosomes, often ce') and (Vogelsangcr Gold*). This material in the form of isochxomosomes. Three months was recorded for a range of quantitative traits after crossing. B chromosomes were eliminated important for yield. Further, nitrogen and from all tissues. Only one plant survived to phosphorous uptake was recorded. Preliminary produce flowering shoots (Linde-Laursen, 10b. analyses of grain yield, straw yield, thousand Cultivated barley is one of the 32 species in grain weight and heading date, using 19 mar the barley genus (Hordeum). These species kers, showed that variation in all the quantita have been studied in various projects all in tive traits correlated with the variation of the collaboration with Roland von Bothmer, Sva- morphological marker v (2 rowed 6 rowed). An iov. and Niels Jacobsen. RVAU. The relation RFLP marker at one end of a group of seven ships between these species were assessed Mcndelian markers located on chromosome 5. using Cicmsa C-banding which produces spe was linked with a QTL for straw yield. cies-specific patterns of cross-bands on the Chromosome-doubled haploid lines from chromosomes (Fig. 3.1.3). Cultivated barley new crosses between modern varieties arc and the wild barley, Hordeum bulbosum. are being established and the derived lines mul rather closely related, whereas they are distant tiplied to produce sufficient quantities of seed ly related to the other barleys. (Linde-Laursen for field trials. et al. 10). This implies that the transfer of Various statistical methods and computer valuable genes, e.g.. genes for disease resist programmes for mapping QTLs have been ance, from the wild species to cultivated bar applied and compared. ley, will be difficult by traditional methods. As an illustration, sixty-five spikes of a H. lech- Cytogenetics of Barley and Related Species leri x H. wlgare F, hybrid backcrossed with H. wlgare resulted in four apparently well- In situ hybridization of DNA probes to chro dcvclopcd embryos in addition to a number of mosomes can be used to locate the position of very small ones; however, none germinated. gene loci cytologically. A project has been Uniparental chromosome elimination, pro initiated, using in situ hybridization, for eluci ducing aneuploidy. occurs frequently in inter dating the connection between distances based specific Hordeum hybrids (Bothmer et ai, 9.1). on recombination frequencies and physical Based on chromosome identification through distances on the chromosomes of barley. The Gicmsa C-banding patterns, elimination was procedure for making chromosome preparations studied in H. lechleri x H. vulgare hybrids. and the in situ hybridization technique are Contrary to previous study of a sample of the being optimized. The technique has already same parental combination, in which all 18 been used to support an autoploid origin of the hypoploids had retained barley chromosome tetraploid cytotypc in the wild barley Hordcum no. 6 (Lindc-Laursen and Bothmer, 9.2), eli marinum ssp. gussoncam.m (4x) by comparing mination of this chromosome occurred at a its rDNA segments with those in H. marinum low frequency in the present sample. Meiotic ssp. gussoncanum (2x). mctaphase I in pollen mother cells (PMCs) of a In barley, chiasma formation is localized hybrid with 2n=26 which had lost barley chro distaily in the chromosomes. It would be of mosomes 1 and 6 plus one H. lechleri chromo- interest to introduce chiasma formation at other Riso-R-624(EN) 19 01 nnp H. roshevitzii H. bogdanii American diploids H secaiinum j 0 DDE Linn H. bu/bosum H. vu/gare H. brevisubulatum H. marinum H. murinum Fig. 3.I.3. Marker chromosomes of 9 Hordeum species. Similarities ofGiemsa C-banded karyotypes suggest a rather close relationship between the East Asian Hordeum brevisubulatum ssp. brevisu bulatum, H. roshexitzii and H. bogdanii and all Hordeum ssp. of the Americas, and distinguish the above mentioned ones from other Hordeum spp. some, but had two copies of barley chromo The project is carried out in collaboration some 7, produced "buds" with different num with Dianna Bowles at The University of bers of chromosomes. This possibly contributed Leeds, UK. Her laboratory has isolated and to a high frequency of PMCs with low chro characterized a number of genes from zygotic mosome numbers. embryos and has information on the temporal and spatial regulation of these genes during In situ Hybridization to Tissue Preparations embiyo development in placenta. At Riso, we have well-established micro In situ hybridization technique is used to get a spore cultures, in which cells undergo embryo- better understanding of the regeneration process genesis (Larsen et al., 9.1, Nielsen, 9.4). Em- of plants from barley microspores (pollen). It is bryogenic structures/tissue from these mi also used to compare gene expression patterns crospore cultures have been selected, fixed and of embryos, formed from microspores in cul embedded in paraffin. The embryo specific ture, with those of zygotic embryos, formed in cDNA-probcs are being used in in situ hybri placenta. dization to (issue preparations of developing 20 Rjso-R-624(EN) microsporc-derived embryos to obtain markers The enzyme could be identified by fluorogra- for the regeneration process. This will provide phy and under UV-Iight after addition of information on the temporal and spatial ex UDP-glucosc and effectors. These results are pression of the genes. These DNA probes can under preparation for a Ph.D. thesis. then be used as markers for the regeneration process. Barley Peroxidase Peroxidases are involved in many biological 32 Mechanisms of Plant-Pathogen processes in plants. They are 1) tissue specific, Interactions developmentally regulated, or modulated by environmental stress factors, and 2) involved in the biosynthesis of cell walk, in the regulation Many different types of general defence me of auxin level, and in response to microbial chanisms exist in plants against fungal attack. attack. Barley peroxidases are studied at the We have studied the chemical compounds cal- lose, peroxidase, and chitinasc of barley and biochemical, physiological, genetical and mo rapesced, and various phenolic compounds of lecular level to delineate the biological function barley. Genetic resources of species-specific of the individual enzymes (Rasmussen et al. resistance in barley to powdery mildew and 9.1). leaf stripe have also been investigated. Finally, It was shown that a full length cDNA for a strong effort was put into elucidating the very- barley seed peroxidase BP 1. found by align specific interaction based on gene-for-gene ment with amino acid sequences of tryptic recognition in the barley/powdery mildew sy peptides of BP 1. had a 21 amino acid C-ter- stem. The study of the gcnctical mechanisms minal extension removed. This indicated that underlying the plant-pathogen interactions was BP 1 is targeted to the vacuoles of immature facilitated by the ongoing characterization of barley endosperm cells. The BP 1 molecule has the genomes of barley and barley powdery one site of glycosylation only, and the se mildew. quence of the major glycan has been establis hed showing a typical structure for plant spe Callose Synthesis in Barley Leaves cies. Part of these results was established du ring two M.Sc. programmes (Johansson, 9.4. Norgaard Rasmussen. 9.4). Barley and other plants respond to pathogens or physical damage by forming cell wall appo Cloning of genes, which code for the barley sitions, papillae, between the plasma membrane peroxidases, aims at a characterization of and the cell wall in the epidermal cells. The sequences which specify the tissue-specific main component of the papillae is the polysac- expression or which are sensitive to stress caridc callosc. which is 1.3-B-linkcd glucose factors. Well-characterized genes will be used units. Callosc is synthesized by the plasma to construct vectors for genetic transformation membrane bound 1.3-fl-D-glucan synthase of barley. A genomic clone Prx6.1 coding for from the substrate UDP-glucose. BP 2A, an isozyme of BP 2 purified from resting barley grains, contains an ititron close Sample purification by the sucrose gradient to the distal histidine. BP 2A is 73% identical purification technique and product-entrapment to BP 1. and BP 2A also contains a C-terminal of the enzyme have pointed towards 3 poly extension, indicating that BP 2A might be peptide components as possible candidates of targeted to the vacuoles. In collaboration with the holo-enzyrnc (Pedersen, 9.2). The molecu Novo Nordisk Ltd., recombinant strains of lar weight of the polypeptides is 35, 55, and yeast are constructed to study the production of 170 kD. respectively. Attempts to prepare po recombinant heme containing BP 2A proteins. lyclonal antibodies against the sub-units failed because of their low abundance. The enzyme A cDNA for a peroxidase, which is induced was partially separated from most of the other by infecting barley leaves with powdery mil plasma membrane proteins by native gel elec dew, was used to isolate seven genomic clones. trophoresis and ion exchange chromatography. Riso-R-624(EN) 21 HIT? BP 2A H*Z IlliZ POX1 HM HM} TAP1 im nm HRP Cl I MI Hil* ATHCa Exoo H Iniron 2M»p Fig. 3.2.1. Sequence- of peroxidase genes: BP 11 barley seed peroxidase; POX 1. * heat peroxi dase; TAP 1. tomato peroxidase; HRP CI. horseradish peroxidase; and ATH Ca. Arabidopsis ihaliana peroxidase. All peroxidase genes sequenced so far. have from one (BP 2A) to three (HRP CI and ATH Ca) intnms. Tlxe positions of inirons in related genes are strictly conserved, whereas the length, as well as the DSA sequence of the introns. sliow no similarity at all. The promotor will be analysed for response A pathogen-induced chitinase was isolated elements of the induccablc peroxidase gene. from cotyledons of rapesced 8 days after in The single copy genes for barley seed per oculation with Phoma Imgam. The enzyme has oxidases BP 1 and BP 2A and the powdery a molecular weight of 30 kD. A partial arr.ino- mildew-induced peroxidase have been RFLP- acid sequence was determined after tryptic mapped to barley chromosomes. The two tight digestion and was shown to have homology to ly linked loci. Prx5 and Prx6 for the seed per amino acid sequencics from chitinascs isolated oxidases are linked to Est4 on chromosome 3. from other plant species. The leaf peroxidase loci Prx7 is mapped on Inoculation of resistant and susceptible chromosome 2. cultivars showed a significant increase in chiti- From the cDNA library, in which the clone nasc activity during the early stages of infec BP 1 was found, other clones for the CM a- tion. Chitinase activity was restricted to the site amylasc inhibitors, histonc, fl-tubulin and ri- of fungal attack and was not systemically bosome genes were sequenced. They arc cur induced. rently included in the RFLP mapping of the A full length cDNA clone corresponding to barley chromosomes. the purified chitinase enzyme, was found and characterized by sequencing. The clone Rapeseed chitinases encodes a 268 amino acid polypeptide. Expres sion studies showed different induction of this In recent years, chitinascs have received atten enzyme in resistant and susceptible rapesced tion as possible agents in plant defence mecha cultivars. The structure of this gene is different nisms. Chitin is not found in higher plants, but from previously characterized chitinasc genes is a major component in the ceil walls of many and indicates the existence of a novel group of fungi. In vitro studies have shown that chiti- chitinascs. These results are being prepared for nase is able to inhibit fungal growth by degra a Ph.D. thesis. ding chitin in the fungal cell walls. Ris«^R-624(EN) |"~) Untreated 600^ II Treated with fungicide 500. CM 400. O) TJ -9> 300 c 5 200 o 100. 12 3 4 5 Variety no. Fig. 3.2.2. Effect of fungicide treatment of barley varieties *uh increasing degrees of partial resist ance to poH-dery milden: Phenolic Compounds in Barky Leaves the fungicide treatment also reduced the impact of other fungal diseases. Indications that phenolic compounds arc of im Leaf samples, harvested during the growing portance in relation to resistance responses arc period, were collected to study 1) the effect of found in some plant species. A preliminary fungicide treatment and nitrogen level on the study in barley using varieties with different content of different phenolic compounds and 2) degree of partial resistance was initiated in the possible correlation between these com collaboration with Bodil Sogaard. RVAU. pounds and the degree of partial resistance in Varieties representing the known variation in the varieties. These assays are being carried out partial resistance to barley powdery mildew- using HPLC techniques. were grown with and without fungicide treat ment, at low and medium nitrogen-fertilizer Genetic Resources of Barley with Resistance levels. The reduction in grain yield when no lo Powdery Mildew fungicide was applied - an estimate of the degree of partial resistance - varied from 5 lo Over the past few- years the MIo resistance of 2tK» irrespective of fertilizer level (Fig. 3.2.2). barley to powdery mildew, characterized by a The mildew- attack was, however moderate, so rapid and efficient papillae formation (Jorgcn- Riso-R-624(EN) 23 sen. 9.4b). ha* become distributed on about 30 Several new promising sources of mildew per cent of the spring barley area in most of resistance have been selected. They are being Europe. Current deliberations consider strate utilized for barley breeding in collaboration gies for maintaining the efficiency of the Mlo with Danish barley breeders. Part of the mate resistance and to avoid a build-up of Mlo ag rial was collected at different sites in Syria and gressiveness in natural powdery mildew popu Jordan by the International Center for Agricul lations (Andersen. 9.2. Jorgenserv 9.4. 10). The tural Research in the Dry Areas (ICARDA) and Mlo resistance in current cultivars originates evaluated further at Risø. In collaboration with from an induced mutant gene mlo9 and some the Nordic Gene Bank (NGB) and institutions Ethiopian landrace barleys, all of which pro in Norway. Sweden and Finland, Riso has eva bably possess gene mlo J I. About 3.200 land- luated NGB barley accessions for morphologic race barleys from Ethiopia were tested for and agronomic traits, as well as for powdery resistance. Of these. 24 had Mlo resistance. mildew- resistance. This activity is part of a Most of them could be traced to a few- loca European programme on barky genetic resour tions in southwest Ethiopia (Jorgcnscn 10). ces (Jørgensen 10). Ten recently discovered Mio resistant varie ties were studied for disease attack and yield in Barley Leaf Stripe field experiments. The Mlo varieties were highly resistant to powdery mildew, but consi The investigations, on resistance to barley leaf derable variation was found in their resistance stripe, have been continued with the aim of to barley leaf rust and scald. Yield losses in obtaining highly resistant varieties for practical untreated, compared to fungicide treated. Mlo use. A dozen varieties, with the formerly de resistant varieties were correlated with the scribed highly effective "Vada-resisti.rcc". decree of leaf rust resistance. have covered a considerable part of the barley 80 I | untreatet [§] seed-dressed 70. (0 *- 60 a. É S> 50. I 2" 40. 1 a 1 >* 30. I Triumph 1 20J f 10. m Fo. Jy. Rø. Ri. Fo. Jy. Rø. Ri. Fig. 3.2.3. Vie effect of seed-treatment against barley leaf stripe [Drcchslcra graminea) on a resistant 'Golf and a susceptible Triumph' variety. 24 Riso-R-624(EN) ?rea in Denmark during the later years. It is long polyA stretches. The method was found to unknown whether virulence is present in Dcn- be inadequate for selecting sequences expressed maik. This is under investigation, but virulence in the early interaction between the fungus and corresponding to the Vada-rcsistance has not the plant. During the study, a highly repetitive yet been found airong the collected isolates of sequence wa" identified and sequenced. Within the fungus. one clone, two almost identical inverted copies The effectivity of the Vada-resistance has of this sequence were found. The sequence was been tested during the 'ast three years at three found dispersed throughout the powdery mil State Experimental Stations and at Riso in dew fungal genome. A similar organization of collaboration with Bent J. Nielsen, The Danish repetitive sequences has been found in other Plant Protection Institute. Uniformly, inoculated organisms. The reason for the accumulation of samples of the Vada-Tesistant 'Golf and the large amounts of inert DNA re: nains unre susceptible Triumph' varieties were compared, solved. untreated and seed-dressed with Fung?zil. No Another approach to the isolation of disease was found in the untreated 'Golf, virulence or avirulence genes is by chromo whereas the seed dressing caused an insignifi some walking. DNA suitable for cloning in cant yield loss. On an average, there was YAC vectors was isolated. Transformation of 12.5% leaf stripe in the untreated Triumph' yeast cells with the YAC vector was estab which caused a vield loss of 9.2 hkg/ha or lished and some clones chaining fungal DNA 12.0% (Fig. 3.2.3). were also obtained. It is, however, still a prob It has been verified (Skou, 9.4b) that experi lem to obtain a sufficient amount of high mo ments with seed dressing against common lecular weight DNA in order to get a large seedling diseases in barley during the last 25 number of transformants. years never resulted in an increased yield. Thus seed dressing of the Vada-resistant varieties is Biocontrol of Barley Powdery Mildew unnecessary, as long as this resistance is effec tive. Biocontrol of powdery mildew with Tilletiopsis species is a promising possibility in green Virulence Gene Products of Barley Powdery houses, above 70%. Some Tilletiopsis species Mildew produce considerable amounts of p-l,3-gluca- nase, which might be a contributing factor to The ability of indiviojal isolates of the powde their effectiveness. The kinds of fi-l,3-gluca- ry mildew fungus to penetrate and establish nases in question are under investigation in themselves in the epidermal layer of barley collabor icn with Karsten M. Kragh and Hans leaves is determined by specific genes. A pre Henrik Dalsgård, Danisco A/S, Copenhagen. requisite is, tiiat corresponding virulence genes in the fungus and resistance genes in the plant, match to a compatible interaction. The function 3.3 Population Biology of these genes is unknown and they can only be determined by the phenotype of the interac Experimental and theoretical studies of interac tion. Two approaches, based on molecular tions between populations are important in techniques, are being used to identify the pro understanding biological systems. Our research ducts of the virulence (avirulence) genes. is particularly devoted to interactions between A cosmid library containing the entire fungul crop plants and weeds, and between crop plants genome has been screened with radioactivcly- and their pathogens. Exchange of genes labeled mRNA from infected barley leaves. between related species, competitive abilites of Sequences recognized by mRNA isolated from crop plants and evolution of pathogen popula infected barley leaves were found, but were tions are the main items investigated. subsequently shown, by sequencing, to contain Riso-R-624(EN) 25 Interaction between GMPs and the Environ In a project initiated in late 1991, in colla ment boration with Maribo Seed, the degree of hy bridization between oilseed rape and the two Genetically modified plants (GMPs) will be natural/naturalized Brassica species in the field marketed within a few years. The risks of gene will be examined. Genetic markers will be used flow from these cultivated transgenics into wild to study the parts of the oilseed rape genome relatives need evaluation. Also, knowledge which are transferred to Brassica campestris about the effect of the new genes transpired to ssp. campestrs and Brassica juncea. Brassica plants in nature is needed, to evaluate the risks campestris ssp campestris and Brassica juncea to the environment from transgenic varieties. In were collected and the first series of manipula- Denmark, spread of transgenes from oilseed t';d crosses were performed (Fig. 3.3.1). rape to the closely related weed Brassica cam- pestris ssp. campestris might be undesirable. Interaction between Crop Plants and Weeds Brassica juncea, occasionally found as a ruderal, may also be able to hybridize with An understanding of the interactions between oilseed rape. crop plants and weed plants is necessary to evaluate the extent to which crop plants can be grown without using herbicides. Cultivation without herbicides may have economical ad vantages, if weeds make use of growth factors which the crop is unable to utilize. In this way the bio-diversity among plants and other orga nisms in the agricultural fields could be in creased. The competitive ability of barley, pea, and weeds was studied in monocultures and in a 1:1 mixture of barley and pea grown with and without herbicide treatment. It was found that barley had a high competitive ability compared to those of pea and weeds. Pea was a weak competitor, and pea biomass production in herbicide-treated plots was higher than the sum of pea and weed biomass in untreated plots. Total production of pea and barley in mixtures, was about the same as those found in mono cultures. Hence, combined cultivation of these two crop plants did not result in an improved utilization of the growth factors. This project was carried out in collaboration with Bodil Søgaard, RVAU. Modelling the Dynamics of Powdery Mildew Populations Fig. 3.3.1. Hybrids between Brassica campes One way to decrease the use of pesticides in tris (see jigure) and oilseed rape are investi crop management is to use genetically deter gated by controlled crosses and w..er field mined resistance in barley to the powdery mil conditions. dew fungus. 26 Risø-R-624(EN) The implication of different strategies for ex Taxonomy of Chrysosporium Species ploiting this genetic resistance has not yet been worked out in detail. Xcrophilic Chrysosporium species are often A project aimed rtf studying this problem was found in association with the fungi of Asco- started in late 1991 at Riso in collaboration sphaeraceae, which cause diseases in solitary with Mogens Hovmoller (Danish Institute of bees used for pollination. Ten new strains of Plant and Soil Science) and Lisa Munk these Chrysosporium species from Denmark, (RVAU). This work will be based on newly Spain, Sweden and Japan were described and established models of changes in virulence taxonomocally separated, along with C. farini gene frequencies of aerial powdery mildew cola (Burnside) Skou (anamorph of Bettsia populations, as a result of selection induced by alvei (Betts) Skou) into a Farinicola series resistance genes in barley (Hovmoller and (Skou 10b). Østergård, 9.2). Risø-R-624(EN) 27 4 Plant Nutrition The objective of this research area is to provide residues and in farmyard manure. Special at a better understanding of those biological and tention is directed towards processes involved chemical processes in the soil-plant-atmos in the cycling of nitrogen, which constitutes not phere environment, which are important for the only a major nutrient source for plants, but provision of plant nutrients. The processes must also a risk to the environment by leaching and be utilized and managed in such a way that gaseous losses. nutrient uptake by plants is optimized. This The study of these research topics will pro will lead to a reduced requirement for energy- vide the basic information needed for increas consuming fertilizers and to a smaller loss of ing the economical and ecological sustainability nutrients to the aquatic and atmospheric envi of plant production. ronments. Mutualistic associations between plant roots and microorganisms are directly involved in the 4.1 Nitrogen in Soil and nutrient uptake by plants. Nitrogen is provided Plants by RJxizobium bacteria, fixing atmospheric nitrogen in symbiosis with legumes. The soil- Our aim is to elucidate the intricate biological, plant transport of mineral nutrients, especially physical and chemical processes involved in phosphorus, is mediated by VA mycorrhizal the cycling of nutrients in the soil-plant-air fungi in symbiosis with most plant species. system. At present, the main emphasis is on The general soil microflora is a biological processes involved in the cycling of nitrogen resource of fundamental importance to the (N) in crop residues, catch crops, farmyard mineralization of nutrients contained in plant manure and mineral fertilizers. Fig. 4.1.1. Vie organic fraction of animal manure are labelled by feeding sheep with 1$S labelled ryegrass and separately collected urine and faeces. Risø-R-624(EN) Cycling of N from Crop Residues and plots in the field. The labelled faeces contained Manure 3.2% N (in DM) and negligible amounts of mineral N. In April, 84 kg N/ha in manure and Nitrogen, mineralized from crop residues and 90 kg N/ha of unlabelled NH4-N were applied farmyard manure, contributes to the nitrogen to the soil to simulate a cow sluny addition. nutrition of succeeding crops, but may also be The N uptake in spring barley was studied in lost by leaching and denitrification. Plant 3 soils with 17%, 8.5% and 4% clay, respec materials and manure labelled with 'N, are tively. About 13% of the labelled N was used for studying the mineralization and plant recovered in the above ground parts of the uptake of N from organic N sources. barley plant, irrespective of the clay content of The plant accumulation of N in autumn- the soil. Calculated by the difference in the N sown winter oilseed Tape and winter barley uptake between barley, with and without addi from 1!N labelled pea straw was studied in a tion of manure, the apparent uptake in barley field experiment during 1990-91. Pea straw from manure N was 6.6%, 9.5% and 15.3% in with 2.6% N, corresponding to 83 kg N/ha was the 3 soils. These resu'ts indicate a higher incorporated in the top soil in September 1990. immobilization and/or denitrification rate of At growth analysis in early December 1990, mineral N after manure application in the soils the total N accumulation in roots and shoots of with the higher clay content. Consequently, the both crops was about 10 kg N/ha higher after fertilizer value of manure N to spring barley incorporation of pea straw as compared to no was higher in sandy soils compared to that in straw incorporation. The higher uptake equalled clayey soils, even though the mineralization of the actual uptake of 15N from the pea straw, organic manure N was nearly the same in the showing a recovery of 13% of the added straw different soil types. N in December. The crops were fertilized with 100 kg N/ha in the spring of 1991, and the Nitrogen Accumulation in Winter and increase in total N from December 1990 until Spring Types of Agricultural Crops harvested in late July 1991 was 160-190 kg N/ha. Incorporation of pea straw in the autumn The cultivation of autumn-sown crops has in also had an effect on final N accumulation in creased considerably during recent years. This the crops. Despite the high uptake of N during is partly due to environmental concern about the growth season, the recovery of labelled N the leaching of nitrate from agricultural areas from the pea straw in barley and oilseed rape and the clajm by "Program for protection of the was only 16% and 14%, respectively. These water environment" that 65% of the arable results indicate that the main part of pea straw land must be covered by growing crops for as N mineralization takes place during the long as possible during autumn and winter. A autumn. Consequently, it is important to estab crop rotation experiment was initiated in 1985 lish a crop in the autumn after the cultivation to measure the nitrogen utilization by winter of pea, in order to Utilize the N mineralized and spring types of barley, rape, wheat and rye from the pea crop residues as efficiently as grown in this sequence in field plots receiving possible. increasing amount nitrogen fertilizers. Studies on the mineralization of N from the The results have shown that the nitrogen organic fraction of farmyard manure have been accumulatipn by the winter types during the initiated. A method for labelling the manure autumn, varied considerably between years, with 15N is being evaluated. The preliminary depending on planting time and growth condi results show that the 1!N enrichments of the tions (Andersen et ai, 9.3). Sowing later than different organic N fracti ..s of the manure normal, in the autumn, resulted in a nitrogen were not completely homogeneous! The easy accumulation in December, which was less decomposable nitrogen fraction was slightly than half the potential in crops sown at the less labelled than the total manure N- right time and grown under favorable growth The plant uptake of nitrogen from 15N- conditions. Comparison of total nitrogen accu labclled sheep manure was studied in micio- mulation in winter and spring types at maturity, Risø-R-624(EN) 29 showed that differences between the two types We have isolated metabolically active bacte of crops were highly dependant on the amount roids enclosed by an intact PBM from pea root of nitrogen fertilizer supplied. At the lowest N nodules. These structures (peribacteroid units. levels almost no differences were found, PBU) were incubated in reaction mixtures whereas at higher N levels the winter types containing various 14C-labelled compounds. By accumulated 30-50 kg N more per ha than the detecting the fate of the ,4C within the PBUs spring types. Considerable variation, however, and in the reaction medium, we have demon occurred between years. strated an exchange of organic acids for amino The results emphasize, that comparison of acids between the symbionts (Rosendahl et al., nitrogen utilization by winter and spring types, 10). The results indicate that the enzymes should be based on crop rotation experiments involved may be located in the membrane performed over several years and with due interface, cither associated with the membranes, consideration to differential rate of growth. or found in the space between the PBM and the bactcroid outer membrane. We have veri fied that the space between the symbionts con tains a discrete set of proteins. Involvement of 4.2 Root-Microbe Symbioses some of these proteins in the exchange of metabolites is currently being investigated. Symbiotic associations between plants and soil-microorganisms are of major importance Mycorrhizas and Plant Nutrition to plant nutrition. Our research in this field includes the physiology and ecology of the The formation of vesicular-arbuscular mycor- les,\imc~Rfti:obtwn symbiosis and VA mycor- rhiza (VAM) between plant roots and soil fungi rhiza. a symbiosis between plants and fungi. has a beneficial impact on the nutrient uptake by the plants. Nutrients in the soil solution are Symbiotic N Fixation absorbed and transported to the roots by the external fungal hyphae. A two-compartment The ability of legumes to establish a symbiotic system makes it possible to distinguish hyphal relationship with R/iizobium bacteria which fix nutrient uptake from direct uptake by the roots. atmospheric nitrogen into ammonia, has been A hyphal compartment is separated from the essential in sustaining the fertility of agricul root compartment by a fine mesh, which re tural land for centuries. Symbiotic N fixation is stricts root growth, but allows free passage of fuelled by products from the photosynthetic the hyphae. activity of the plant. This input of nitrogen into Hermetically sealed two-compartment units the crops is derived from solar energy, rather were used for measuring the carbon:phosphorus than from the fossil energy used to produce (C:P) exchange ratio of three VAM fungi in nitrogen fertilizer. symbiosis with cucumber plants. An aqueous 3: The Riuzobium bacteria inhabit root nodules solution of P was supplied to the hyphal on the legume, where they transform to the compartment of 3-week-old plants just before I4 nitrogen-fixing bacteroid stage. In effective the exposure of shoots to a C02-enrichcd 14 root nodules, the Rluzobium bacteroids are atmosphere for 16 h. The C transported to the 32 enclosed by a plant-derived peribacteroid hyphaé, and the P transported to the plants, membrane (PBM). were measured after a 72 h chase period. The Information on the exchange of compounds C:P exchange ratio differed markedly between between the host plant and the microsymbiont the fungi. This was caused mainly by major across the membrane interface is valuable, differences in fungal P transport, rather than in because it reflects how a mutualistic relation the fungal C drain, which did not differ in the ship is maintained. Furthermore, the rate of three isolates. The length of external hyphac symbiotic nitrogen-fixatipn is likely to be con also differed markedly between fungi, but P trolled by this exchange of compounds (Rosen transport was not related to amounts of hyphae. dahl et-al., 9.1). 30 Risø-R-624(EN) The rate of hyphal transport of P and N was studied in subtenanean clover associated with a single VAM fungus. 32P and 15N were supplied to a hyphal compartment at 2 and 5 cm distan ces from the root compartment. Transport into the plant was measured by the presence of the isotopes in leaflets harvested each day from young fully expanded leaves. After only three days, the radioactivity was higher in the leaves of myconhizal plants than in those of nonmy \\ sVsX^v x\\\v; VAVsS corrhizal plants. After this lag phase, the radio activity in mycorrhizal plants increased sharply. 15N analysis are not yet finished, but the results seem to be confounded by the transport of 15N in the soil by mass flow. The influence of soil organic matter on pro duction of VAM hyphae was studied with myconhizal cucumber. Moist soil amended with chopped wheat straw (0, 10, 30 or 90 g/kg soil), was incubated for 14 months. The mix tures were filled into hyphal compartments and the mycorrhizal plants were grown for 31 d. The length of external hyphae was increased Fig. 4.2.1. Two compartment system for study when increasing amounts of straw were sup ing hyphal P transport to pea in the field. plied. The background for this interaction is not yet known, but the influence of organic matter The two-compartment system has been used seemed to be exerted directly on the external to directly demonstrate P transport by VAM hyphae, since root colonization was not hyphae under field conditions. PVC tubes, with affected. most of their walls replaced by a fine mesh, served as hyphal compartments. They were Nitrogen Transfer from Legumes to buried in the plough layer of plots with pea Non-Legumes plants (Fig. 4.2.1.) and the tubes were filled with 32P-labelled soil. The specific radioactivi Nitrogen fixed symbiotically contributes mainly ty (cpm/g leaf P) was considerably higher in to the N nutrition of the legume host, but N mycorrhizal pea plants than in nonmycorrhizal mineralized from legume root exudates, nodu plants grown in fumigated plots (Jakobsen et les and roots may contribute to the N nutrition al, 10). of other plants growing in association with the Hyphae of VAM fungi are also able to trans legume. Furthermore, if plants are colonized by port nitrogen (N) to their host. Soil in a hyphal a common VA mycelium, nutrients may be compartment was supplied with 15N-labclled transferred from legumes to non-legumes. In ammonium and the hyphal transport of ,5N by terspecies transfer of nutrient is being studied a single VAM fungus was studied in relation to using 15N and 3:P as tracers. the N status of cucumber plants. Myconhizal In experiments carried out under controlled plants with low and medium N status (105 and environmental conditions with intercropped pea 217 mg N) contained 45% of the applied 1!N and barley, pea plants were labelled with ,5N after 27 d; the corresponding figure for plants using either a split root labelling procedure or with high N status (425 mg N) was only 26%. leaf labelling with 15N. Both labelling methods This indicates that the symbiosis may control demonstrated that Ihe transfer of 15N from pea the hyphal N transport in relation to the N to barley occurred before the pod-filling demand of the host. growth state. Using split root labelling for 35 Risa-R-624(EN) 31 days, the results showed that a total of 2^ of Riso and The Rubber Research Institute of the N in pea was transferred to barley, when Malaysia are currently studying the pathways pea and barley roots occupied the same soil of N transfer from a creeping cover crop volume. The N transferred, corresponded to legume {Pueraria phaseoloides) to rubber trees about 15% of total N in barley, »hen plants (Hevea braziliensis). The main focus is on the were grown with a low supply of mineral N. role of VA myconhizas in the transfer of N When the plant root systems were separated by and P. a 20 n nylon mesh, the transfer of pea N was about 50% of the transfer in the treatment with roots growing in the same compartment. Fig. 4.2.2. Rubber trees (Hevea brasiliensis) are grown with a cover crop legume (Pueraria phaseoloides) in compartmented containers for studies of S and P transfer. Rubber left side of boxes. 32 Risø-R-624(EN) 4.3 Effects of Air Pollution on Does Ozone Interfere with Carbon Translo Plants cation in Wheat? The effect of ozone on the transport of assimi lates was studied in collaboration with Depart Forest Decline and Ammonia ment of Emissions and Air Pollution, NERI (National Environmental Research Institute) in A serious decline in Norway spruce (Picea the Open Top Chamber facility. Ozone-da abies) has caused much damage to plantations maged plants often show altered carbon alloca in Jutland during the last 3-4 years. Up to 20<<> of the trees have died, particularly along tion with reduced root growth, and the present forest edges. Among the many hypotheses on investigation was done to find out if the cause the causes are mild winters, making trees of these effects might be due to a reduction in respire themselves to death, salt damage after translocation velocity or efficiency. gales, ovcrfcnilization with ammonia from the Spring wh -at plants grown in standard air, in air, or a combination of these stresses. Most of air filtered through activated carbon, or in air western Jutland is a pristine area with low air with added ozone, were allowed to take up ra pollution, but calculations indicate that up to 50 dioactive CO, in a small leaf cuvette for 5 mi kg ammonia may be deposited per ha. liberated nutes. The plants were harvested after different from fertilization with slurry and from stables. intervals, freeze dried and autoradiographed on Wc arc investigating the reaction of 4- and X-ray films. The amounts of radioactivity were 2-ycar-oId Norway spruce in pot cultures in measured in the plant material by scintillation sand, to overfcrtilization with nitrogen relative counting after solubilization in sodium hypo to P. K and the other nutrients. Heavy fertil chlorite. ization with nitrogen over 2 years resulted in There were no indications that ozone inter needle loss in the older seedlings, and some fered with the translocation process, neither in symptoms were evident after 1 year in the its speed nor in the percentage exported from small seedlings. However, the symptoms are the leaf. However, the variability in the not exactly like those seen in the field, in Da "pscudo-field-grown" material was quite large, nish called "rode rodgraner". so that minor effects could not be discerned. It must therefore be concluded that the influence of ozone on carbon allocation can be explained by other mechanisms. Riso-R-624(EN) 33 5 Chemistry of the Geosphere 5.1 Geochemical Modelling 52 Applied Geochemistry The previously mentioned geochemical compu Methods terprogram. JENSEN, has successfully been applied to predict the possible geochemicai In cooperation with the company Tracechem, transformations to be expected when foreign application of instrumental neutron activation minerals are added as reactants to polluted strategies for large-sample analysis were waters. In addition, a thorough validation study carried out in 1991. Theoretical and experi of carbonate equilibria, involving both theoreti mental data were presented at the 8th Intern, cal and experimental work was performed. conference on "Modem Trends in Neutron A new EEC contract, which was started re Activation". Vienna, September 10 - 16,1991. cently, is concerned with the quantification of (Gwozdz et al, 9.2). A book review was writ the behaviour of humic acid colloids exposed ten for the journal Lithos (Kunzendorf. 9.1). to multi-element salt solutions. Preliminary Radioisotope ED.X measurements were tests, to identify the concentration ranges of applied in small projects for students of the interest, have clearly demonstrated competition Institute of the Environment, Technology and between ions for the available adsorption sites Social Studies. RUC. Both EDX and gamma and thus indicate which model be applied. spectrometric methods were later used by stu In another EEC contract concerned with un dent groups involved in projects describing certainties in the modelling of migration, the fcrromanganese crusts and heavy mineral possible effect of unknown inhomogene itics on deposits from the isle of Anholt. the extent and path of migrations are studied. The concentration distribution, resulting from Terrestrial Geochemistry three-dimensional diffusion from a source through a medium containing randomly dis A final report (Kunzendorf ct ai, 9.3) has been persed inhomogencitics. was calculated and prepared regarding the energy research project analysed. A linear relation between an apparent Timc-tcmpcrature variations in sediments diffusion coefficient and the porosity of the from the Central Trough area and the Danish medium was established, as well as the uncer Subbasin evaluated by fission-track studies of tainties to be ascribed to them. This relation is cuttings from selected drill holes" (in coopera not valid in the case of two-dimensional diffu tion with the University of Copenhagen). sion. In a recently developed 2-D basin modelling The convective flow through networks of fis programme, fission track length distributions in sures and pores will be simulated by the apatites from drill hole D-l (north of the Cen adaption of Kirchhoffs laws for the flow of tral Trough area) were measured. Using these electricity through networks of conductors. The data, instead of traditional vitrinite reflectance results of these studies will be used to describe data, it was found that the sediments in the dispersion processes and to estimate the uncer hole were subject to uplift/erosion before their tainties and other characteristics of the effective emplacement. Furthermore, the modelling, dispersion coefficients obtained. The algorithms using fission track data, also suggests subsi needed for these calculations have already been dence of sediments at late dcpositional stages. constructed and tested. 34 Risø-R-62-HEN) f- Camus no I - Ernsbrf To»n!«nd Crar.Ue -t J ! s to r P RMl/Olt - OK MI/SI« -Mm Mll/US - «0 •> O Cl:/eu - M a •HI/OK - M at • CSi/e:T. Mn CHI/VIZ • Ha « t\- • cii/en - too m »m/00« - ix iii • csi/ws - IK m RMI/00« - 120 m . I u :• Pr N r« sm [• « n g< h [i :» n i> u :t ft MPBIKII un t) Mb txtt u Fig. 5.2.1. Chondrite-normalised REE profiles for drill core samples of Irish granites, a = bore hole Camus no. 1, b - borehole Ros a Mhil. both from the Galway area. Studies of rare earth elements in the Galway lished in a special volume of the journal Gco- granites contributed to a publication by the logischcs Jahrbuch. Hannover. University College Galway. Ireland (Fcely et Fcnomanganese crusts and nodules from ai, 9.1). Based on surface and drill core New Zealand waters were analysed for rare and samples, it could be shown that granodiorites other elements. The data was able to devide the and granites display light-REE enriched pat crusts into two different types with distinct rare terns, while the more evolved granites show earth element patterns. A summary of this work large negative Eu anomalies and heavy-REE was published in the NZOI journal (Glasby et enrichment. «/.. 9.1). Hydrogenous and hydrothermal ferro- Marine Geochemistry manganese crust data from the South Pacific were published in cooperation with the Univer Rare and precious metals were studied in mari sity of Kiel and NZOI in the journals Marine ne sediments and fenomangancse phases from Geology and Marine Mining (Puteanus et at., the Pacific. Investigations of metalliferrous 9.1; Sluben et al, 9.1). Our input into this sediments from the back-arc spreading area, work was mainly in the form of rare earth the Lau Basin (Kunzendorf et al, 9.1), re element studies. vealed significant amounts of gold in the sedi Radiometric methods for the inspection of ments suggesting hydrothcrmal activity in the the sea floor arc described in "Handbook of area. Results (in cooperation with the Univer geophysical exploration at sea" to be published sity of Heidelberg and the New Zealand in 1992 by CRC Press, U.S.A. A newly devel Oceanographic Institute. NZOI) were pub oped radiometric sonde (cooperation RUC/ Risø-R-624(EN) 35 Riso) was tested on board the research vessel Fixation of Heavy Metab in Soil Gunnar Thorson. Data and preliminary work with the sonde were presented in the form of The work on binding metal ions to clay mi posters at the "2nd International Symposium on nerals continues. Experiments with mercury Environmental Geochemistry" in Uppsala. give promising results. An experimental pro Sweden, and at the "Second Marine Geological gramme, comprising both leaching and identi Conference - The Baltic" in Rostock. Germany fication of fixed species, as well as plant (Kunzendorf and Schroder a and b. 9.2). growth experiments, were discussed with scientists from UK and Spain in preparation for EEC support. 53 Geochemical and Applied Preliminary pot experiments with Italian rye Technology grass are in progress. Wet Oxidation of Organic Material Marine Environmental Technology In 1991, discussions ended regarding the Applied research into specific cases of pollu scientific and technical cooperation between the tion have continued in parallel with more fun Applied Geochemistry group, the Institute of damental research projects. The latter include Environment, Technology and Social Studies an investigation of the oxidative decomposition (RUC) and the Danish Road Institute (Road of polyolcfins and paraffins. An intriguing Directorate). Cooperation is now channelled feature is the production of significant amounts through the Baltic Marine Cooperation (BMC) of hydrogen during the wet oxidation. which is connected to the Center of Advanced The oxidation of dicarboxylic acids was also Technolocv. studied. Fig. 5.3.1. Grog's vie*' of the pipe reactor belonging to the Chemistry Section. Tfiis reactdr is used for reclamation of polluted soil in a semi-industrial scale. 36 Risø-R-fi24(EN) An attempt in the utilization of wheat straw new detector already in function. New HPLC can be used as an energy source when prt- equipment will be permanently installed. treated by wet oxidation. The wet oxidation is The wide variety of analytical problems, followed by enzymatic hydrolysis, which which have been solved, are reflected by the breaks down the very resistant glucosidic cel following activities: Participation in research lulose bonds. The yield of glucose was found projects including DCAR-projects on air pol to be more than 80Tk lution, syntheses of commercial organic pro ducts, plant uptake of toxic elements from sta bilized soil industrial projects on improving 5.4 Chemical Analysis methods for purification of soils and gasses. BCR reference material to EEC. geological Chemical analysis followed the main lines laid formation with rare earths, and human nutri out in the previous yearly report and relied tion. heavily on atomic absorption (AA). ionchro- Development of methods has continued to matography (IQ. and inductively coupled plas concentrate on trace analysis, the use of ma mass spectrometry (ICP/MS). enriched non-radioactive isotopes, and per With a new grant from SJVF. an electrother formance of multielement analysis. The group mal vaporisation (ETV) unit linked to the is in an excellent position to select interesting ICP/MS instrument, will be in operation in portions of many national and international early 1992 and creates the possibility for direct proposals in collaboration with a variety of introduction of solid samples. Determination of partners. NO-," in samples high in Cl~-contcnt and ana A substantical part of the activities consisted lysis of phenol- containing water samples was of servicing the reactor DR 3. and other Riso successfully carried out with IC attached to a Large Facilities plus commercial contracts. Fig. 5.6.1. An example of a so called CROliyETHER which selectively binds the potassium ion in the larger ring. Ris«t-R-624 In recent years a substantial knowledge has In 1991. MODECS arranged a one-day meet accumulated concerning the non-traditional ing on "Surface Modifications of Polymers and properties of organic molecules. New insight Biocornpatibiiity" and a two-day meeting on into the detailed structures, which are respon The Design of Novel Polymeric Materials sible for the optical-, electric-, magnetic- and with Special Properties", both with interna catalytic-properties of these molecules, sug tionally renowned specialists as main speakers. gests new applications in sensors and other Inspired, and partly financed by MODECS, a devices. This creates a need for organo-che- Ph.D.-study has been initiated. The study mtsts with synthetic skills. focuses on collective physio-chemical pheno The group at Risø has. through the years. mena, which arise when functional units are been involved in several commercial projects immobilised on surfaces or macro-molecules. ranging from the preparation of isotopically A deeper understanding of these events is of labelled compounds, to the attachment of su- importance when designing and developing pramolecular units to both natural sensors, as well as in describing many macromoleculcs and polymer surfaces. The interfacial phenomena. group is. at present, working on the synthesis During the last year, five new firms have of catalvucally active metal complexes, bonded become members of MODECS. to clcctroconducting organic polymers. The group is also engaged in educational activities. The activities of the group are closely related to those in the MODECS R&D Forum, in which both industrial firms and research insti tutions follow newer trends in basic and applied supramolccuiar chemistry and related topics. 38 Risø-R-624(EN) 6 Ecology and Mineral Cycling 6.1 Ecological Halflives where TE/ln2 is the ecological mean residence time of the radionuclide in the environmental The main sources of the present radioactive sample in question. In practice, it appears that contamination of our terrestrial environment are the environmental decay follows a number of global fallout from the nuclear weapons testing exponential decays (a power function) rather in the atmosphere and regional fallout from the than a single exponential decay. Just after the Chernobyl accident. deposition of a radionuclide, there is a rapid The global fallout has been deposited mainly decrease in the activity, due to environmental by precipitation. It originates from stratospheric processes such as wash-off and weathering. inventories, which were created by the power Later, when the activity has penetrated the soil, ful thermonuclear test explosions carried out up it decays more slowly. The activity will be to 1980. The radioactive debris in the stratos increasingly fixed to the soil and root-uptake phere has a mean residence time of about 1 will continue to decrease. The ultimate ecolo year. Hence the stratosphere no longer contri gical halflife of a long-lived radionuclide will butes to the global fallout. The Chernobyl approach the radioactive halflife. accident in 1986 injected radioactive debris A comparison of what happens in the Danish into the troposphere, where the mean residence and the Faroese environments is well suited for time of fallout is only a few weeks. a study on the variation of ecological halflives, In the last five years, therefore, we have had because the environmental conditions are so the opportunity to study the behaviour of two different in the two arias. The Danish agricul sources of radioactive contamination in the tural ecosystem is intensively cultivated and the environment unperturbed by new inputs from soils are low in organic matter and high in clay the atmosphere. This has allowed us to study minerals, whereas in the Faroe Islands, the ecological halflives of "old" and "new" radio- ecosystem is semi-natural, and the soils are caesium. The old comes from the global stra generally low in minerals and high in organic tospheric fallout and the new from the Cherno matter. Fig. 6.1.1 and 6.1.2 illustrate the decay byl activity. of Cs-137 in Faroese and Dansh milk. It appears tliat the ecological halflives of the The ecological halflife (TE) of a radioactive pollutant is a combination of its environmental Chernobyl Cs-137 are shorter than those of the global fallout. The short ecological halflife of (TM) and radioactive (TR) halflives: Chernobyl Cs-137 is due to a rapid decrease in 111. — - — + — i.e. the Tesuspension of Chernobyl Cs-137, a pro TE TM TR cess that otherwise has been responsible for the the ecological halflife of a radionuclide in an continued direct contamination of the crops. environmental compartment is identical with its We expect, however, that the ecological half- effective halflife. When the consequences of a lives of Chernobyl fallout in the coming years will approach those of the global fallout. given radioactive pollution are to be evaluated, it is necessary to know the ecological halflives Remarkably, the ecological halflife of Cs- of the pollutants in the various foods produced 137 in Faroese milk is about half that in Da in the contaminated environment, because the nish milk. This is much shorter than in other dose to man depends on the infinite time inte seminatural ecosystems, e.g. in Norway and gral of the radionuclide concentrations in food- Ireland. We btlieve that this is due to a relative rapid penetration of the soil column. Run-off products. If the initial concentration is CQ -1 to the sea from the Faroese soils also plays a Bqkg and the ecological halflife is TF years, the infinite time integral then becomes role. Measurements of Chernobyl Cs-137 in Faroese soils have shown that in 1991, only half of the originally deposited activity nuin C0X jjg-Bqkg-V 1986 remained in the upper 30 cm of the soil. 39 Risø-R-624(EN) 100OO 10000 . \ . • \ Global fallout • • \ • • \ A Chernobyl - - 5000 5000 - •X . • • CO 30OO -- - 3000 jr A\ CO W 2000 - - 2000 O A\ CX • m A. • 1000 - '\A -- 1000 • \ - • »\ • • \ • \ - " 1 ^N. 500 I I I I I i i i 500 1982 1984 1986 1988 1990 YEAR Fig. 6.1.1. Decay of Cs-137 in Faroese milk. Tlie data are based on yearly means of monthly collected samples from 3 locations (Viorshavn, Klaksvig, Tvcera). Vie Chernobyl levels were calculated from Cs-134 and the theoretical ratio ofCs-134ICs-137 in Cherno byl debris (= 0.55 at April 26, 1986). Vie eco'ogical halflife of global fallout Cs-137 was 2.8 years and that of Chernobyl Cs-137 was 1.6 years. 3000 3000 Global laliout • 1000 r 1000 Chernobyl CO 300 - 300 to i 100 -.100 w O CT CD 10 10 _L 1982 1984 1986 1988 199C YEAR Fig. 6.1.2. Decay of Cs-137 in Danish milk. The data are based on monthly samples of dried milk collected in West Jutland (Itdebcek). Cf. remarks to Fig. 6.1.1. Vie ecological halflife of global fallout Cs-137 was 7.1 years and that of Chernobyl Cs-137 was 1.6 years. 40 Risø-R-624(EN) Fig. 6.1.3 shows the decay of another iso fodder is e.g. of great importance. This compo tope. Sr-90, in Faroese and Danish milk. In sition may not only differ from place to place, this case, the source is global fallout only. It but may also change with time. The longer appears that Sr-90 has a longer ecological ecological halflife of Sr-90 and Cs-137 in hatflife than Cs-137 and that the ecological Danish, compared with Faroese milk, may be halflife of Sr-90 is longer in Danish than in influenced by such factors. The production of Faroese milk. This has now led to higher Sr-90 Danish milk has, throughout the years, moved concentrations in Danish milk than in Faroese, towards western Denmark, where the original although the Faroese milk originally contained contamination levels were higher. Faroese milk significantly more Sr-90 than the Danish. has in the same period, to an increasing extent, It is important to remember, that the ecologi been based upon imported fodder, which has a cal halflife of a radionuclide in an environ lower Sr-90 content than that found in Faroese mental sample such as milk, depends on nu grass. merous factors. The composition of the cows 300 300 FAROESE DENMARK —•— -A- 200 - - 200 \ • \# 03 O o 100 - 100 • CO .„ A \ cr GQ A --. -. A \ 50 - """•V.. -- 50 XV": i , i 30 i—,—i—,—L_: •30 1982 1984 1986 1988 1990 YEAR Fig. 6.1.3. Decay of Sr-90 in Danish and Faroese milk. The ecological halflifes were 9.7yea J in,Danish milk and 3.5years in Faroese. Riso-R-624(EN) 41 6.2 Influence of Plant Varietv on Danish sandy-loam from Riso, and an organic the Root Uptake of Radiocaesium soil from Gavle, in Sweden, which received a large deposition of radiocaesium from the The long-term consequences of radioactive Chernobyl accident. The experimental design contamination in agricultural ecosystems included four replicates in each group. depend partly on the transfer of radionuclides Caesium-137 was experimentally added to the via roots from soil to vegetation. The fact that sandy- loam, and the organic soil, which was the transfer rates of radiocaesium from soil to contaminated with Cs-137 from the Chernobyl plants in organic soils are significantly higher accident, was supplied with Cs-134. The pots than those in mineral soils has been known were seeded immediately after the isotopes since the 1960's from studies of nuclear were added to the soils. weapons fallout. The objective of the present The barley was harvested in August, and study, was to investigate the transfer of radio regarding the rye grass, five successive cuts caesium from organic and mineral soil to va were taken in the period from June to October. rieties of different crops, in order to identify The experiment was repeated in 1989 and 1990 statistically significant differences between using the same pots. The upper 10-15 cm of varieties. soil in the pots were mixed in the spring, rcsown in May and the barley harvested in A pot experiment (Ohlensc1 æger and Gissel- August. Statistical analyses were performed on Nielsen, 9.1; Øhlenschlæger, 9.3) was started in the log-transformed concentration ratios (Bq 1988, where 56 pots were seeded with spring per g plant relative to Bq per g soil, both dry barley varieties (Golf. Apex. Anker and Sila), weight), as the data were log-normally distri perennial rye grass varieties (Darbo and Patoro) buted. and an Italian rye grass variety (Prego). Each crop was grown in two types of soil, a typical 200 150 - < e. a 100 - to J < 2 ec 50 - o z m Y_1990 D Y_1989 • Y-1988 APEX GOLF ANKER SILA VARIETY Fig. 6.2.1. Root uptake of radiocaesium in barley-grain varieties from the years 1988, 1989 and 1990 expressed relative to the uptake for the variety Apex. Every bar represents the mean of 12 results-averaged across three soil/isotope groups with four replicates in each group. 42 Risø-R-624(EN) The results for the barley grain are shown in costs. By introducing biological samples in a Fig. 6.2.1. Analyses of the data show that there monitoring programme, one inevitably intro are statistically significant differences (30- duces a variation with several environmental 40%) in root uptake for these barley varieties. parameters, such as season and salinity. It is The barley variety Sila has a significantly important to know this variation in bioindicator higher root uptake and the barley variety Apex, response, as insignificant differences between a significantly lower root uptake of radiocae- data sets could otherwise be misinterpreted. sium in all experimental groups. Similarly, for Nevertheless, the variation docs not prohibit a the grass varieties, the Italian rye grass was meaningful use of the bioindicators. In addition identified as the one with the relatively highest to the "applied** aspects of improving the use uptake of caesium for all the groups. The up of mussels in bioindicator programmes, the take was almost a factor of two higher for the study of trace element cycling in marine and Italian rye grass than for the other two varie estuarine environments, including its variation, ties, averaged over the growing season. forms an important part of our general under The results thus indicate, that it is possible to standing of nature's "household". reduce the radiological consequences after a nuclear accident by efficient planning of countermeasures. These could comprise changes of agricultural practices towards the use of plant species and varieties with low- sensitivity to radioactive contamination. 6.3 Variation in Trace Element Loss Rates from Baltic Mussels Mytilus edulis The mussel, Mytilus edulis. is probably the most widely sampled bioindicator organism in marine monitoring programmes for various pollutants, mainly radionuclides and metals. One of the reasons for its popularity is its wide distribution. It is found from temperate to arctic waters, from fully marine areas to estuaries showing permanent salinities as low as 3-5 %c. It is furthermore quantitatively dominating in several low-water environments, e.g. in large parts of the Baltic sea. Another interesting characteristic of Mytilus relevant to its metal and radionuclide metabolism, is its filter feed ing. There are several advantages of including Figure 6.3.1. Mussel experiment in the Baltic biological indicator organisms, like mussels, in at Oscarshanm. Vie experimental animals, monitoring programmes: biomagniftcation im used in a long term loss study, are situated in proves detection limits, time integration the floating cages. smooths fluctuating environmental levels of pollutants as the result of long-term retention, Two long-term //; situ loss studies with 12 and the sensitivity is greatest for the most radioactive trace elements in two Baltic Mytilus bioavailable, elements and chemical species. edulis populations were made at the Forsmark These advantages arc, however, not without Biotest facility. 120 km north of Stockholm. Riso-R-624(EN) 43 and at Oskarshamn. 250 km south of Stock 6.4 Fish Ecotoxicology holm, respectively. Results showed large dif ferences between biological half-lives and What happens to larval or small post-laTval retentions at the two sites (Dahlgaard. 9.1). At fish that are set out in the environment to least part of these differences may be explained secure a natural population? Do they ever reach by low food availability. It is suggested that maturity in amounts large enough TO influence "starving" mussels, not having access to suffi the fishery? What is the effect of the enhanced cient food to sustain growth, show a prolonged ambient temperatures in a thermal effluent retention of trace elements; i.e. when the from an electricity generating plant? energy metabolism is reduced, the rate of trace Stockings of elvers (Anguilla anguilla) were element turnover is also reduced. Such a coup made in 1982 and 19S4 in the cooling water ling between energy metabolism and trace ele effluent area from the Swedish nuclear power ment metabolism includes not only biologically plant at Oskarshamn (unit III, 1060 MWe) on active elements such as Co, Zn, Mn and Ag, the Baltic coast south of Stockholm. The elvers but also elements with no known biological were tagged with 1:°Eu and l!,_Eu, respective function, such as Pu, Am, Cm, Ce and Eu. ly; recaptures were made from 1983 to 1989, Under normal food and growth conditions, a based on samplings at monthly intervals. At dilution of the accumulated trace elements, due our laboratory, about 10 cm of backbone from to new growth, may be more important in de each animal was removed, ashed and counted termining trace clement concentrations than the for Y-radioactivity. first with a Nal aystal and actual loss of metals or radionuclides from the then, if any europium was found, further veri animals. It should, therefore, be expected that fied by using a Ge-Li detector. Detection of metal and radionuclide concentrations might be taggeu eels was found to be possible for at much higher in a starving mussel population least 7 years after stocking. Originally, the than in a fast growing one. This is very im tagged elvers weighed on the average 0.21 g; portant for the interpretation of mussel data in the largest detected eel weighed 447 g bioindicator monitoring programmes. (Anderson, et al, 9.1). This showed a remark able degree of europium reabsorption from the original cartilage by developing eel bone. Fig. 6.4.1. An eel is seen compared to its appearance for years earlier, when it was a few months past the elver stage. Even though it has grown by a factor 300, it has retained most of its original radioactive label. 44 Riso-R-624(EN) At the end of the study (Anderson, et al, 9.1) problem. RIMI involves scientists from the 3.5% and 1.3%, respectively, of the two Environmental Science and Technology De stockings had been recaptured. Although the partment, as well as scientists from the Meteo area was open to the sea, the heated water rology and Wind Energy Department and (10°C above normal) evidently induced many Optics and Fluid Dynamics Department. of the eels to remain near the power plant A field station was established in 1990-1991 during their juvenile life. In the spring of 1987, in order to study the atmospheric chemistry of as much as 53% of the total capture were nitrogen compounds under field conditions and tagged eels. The average growth rate was 7 the exchange of nitrogen compounds between cm/year during the first five years, which is the atmosphere and terrestrial ecosystems. The significantly larger than normally expected in field station is placed in a conventional Danish Swedish waters. There was no evidence of ne agricultural area two kilometers from the Riso gative impact on body condition (weight/ National Laboratory. The field station is com length-cubed) or fat content, relative to control prised of a ten meter high meteorological mast eels at Halmstad on the Swedish west coast. placed in the middle of a cereal field with an It could generally be concluded that thermal instrument hut placed at the margin of the discharge areas in temperate Scandinavian field. The mast and the hut are connected with waters evidently favour eel growth and devel underground wires for power supply and data opment. Radioactive europium has been shown transfer. The data acquisition system is con to be an excellent long-term mark for elvers. nected to the data network at Riso. The field station is equipped with instruments for mete orological parameters and chemical compounds. 6.5 Rimi Field Station The use of the field station is open to other institutions, provided that a reasonable coope In 1990, Riso National Laboratory initiated an ration on projects of mutual interest with RIMI interdisciplinary research, "Riso's Integrated is ensured. Environmental Project" (RIMI). The project is In addition to the basic instrumentation, seve aimed at the study of pathways, processes and ral other ir struments connected to special pro effects of nitrogen compounds derived from jects are placed at the station for shorter or human activities. The project focusses on the longer periods. terrestrial environment. Deposition of nitrogen Meteorological parameters and concentrations compounds emitted into the atmosphere plays of ozone, nitrogen dioxide and sulphur >>',oxide an important role in both acidification and have been monitored continuously since Febru cutrofication of ecosystems, and there is a sub ary 1991. The station has been the basis for stantial need for more precise information on studies of fluxes and chemical composition of both qualitative and quantitative aspects of the aerosols. Basic instrumentation at field station: PARAMETER INSTRUMENT PARAMETER INSTRUMENT Wind speed Cup anemometers Rain Tipping bucket Wind direction Wind vane Aerosol cone. LP impact or Wind fluctuation Sonic Aerosol flux Optical counter Temperaiure PT 100 and 500 Ozone Flux Chemilumin. Humidity Hygromeier NO., and NO flux Chcmiiumin. Water vapour flux IR-hygrometer Ozolie cone DOAS and sonic NO,, cone. DOAS Radiation Radiometer SO ~ cone. DOAS Surface temperature IR-Tbeimomeiei "* Risø-R-624(EN) 45 The station also serves as a background sta 6.6 Radioactive Tracers in the tion for air pollution in Copenhagen (by the Greenland Sea National Environmental Research Institute) and has been the site for an intensive measuring Several watt- masses of different origin can be campaign in August 1991 within the distinguished in the Greenland Sea. Knowledge EUROTRAC-TOR project, dealing with tro- of the origin of these water masses is of im pospheric ozone and related chemical reactions. portance in the understanding of their role in The Danish TOR-project is carried out in the World Ocean circulation, including deep cooperation with the National Environmental water formation. The measurement of different Research Institute. £0°W Fig. 6.6.1. Selected currents of particular importance for the transport of European discharges to the Greenland Sea. Part of the low concentrations of manmade radioactive elements in the Greenland Sea and the East Greenland Current have been identified as English discharges. The transport route, from the English west coast at Sellafield goes through the North Sea, the Norwegian Coastal Current and the West Spitzbergen Current to the East Greenland Current. 46 Risø-R-624(EN) tracers, including a variety of man-made ra The results show that measurements of radi dionuclides, can provide a major contribution oactive tracers give a valuable supplement to to this understanding. In the Greenland^ Sea the traditional oceanographic measurements by Project, »e have utilized the nuclides l*7Cs. introducing a time factor following geographi ^Cs, and "Tc. cally well-established release peaks. The The main sources of ^"c in the Greenland release of **Tc from Sellafield in the late Sea are controlled discharges from Sellafield 1970s was one such peak; the release of 137Cs (formerly Windscale) into the Irish Sea and. to from the Chernobyl accident in 1986 was a lesser extent, La Hague discharges into the another. English Channel. The contribution from global fallout, to the measured »Tc concentration in the surface waters of the East Greenland Cur 6.7 Radioecological Cooperation rent, has previously been estimated at only 10- 20^J. The concentrations of "TC are highest in with the former USSR the part of the East Greenland Current closest In the spring of 1991 a "skim and burial" to the Greenland coast, i.e. in the Polar water plough, developed at Riso in collaboration with (Dahlgaard et al. a, 9.2) the "Bovlund" plough factory, Jutland, Den The discharges of "Tc from Sellafield mark, was put through a final test. (Fig. 6.7.1, peaked in 1978. and dropped by an order of next page). The plough can remove a contami magnitude by 1981. The transport time from nated top-layer of approximately S an of soil Sellafield to the East Greenland Current was and bury it beneath some 45 cm soil, without previously estimated to be "7 years. Presumab inverting the 5-45 cm layer in between. This is ly, the La Hague discharges reach the area two done to avoid less fertile subsoil being brought years faster, but Sellaficld was still the domi to the surface and at the same time, allowing nant source of "Tc in the Greenland Sea in normal tilling procedures to be carried out 1988. without contaminating the 20-25 cm layer of Assuming that the Chernobyl accident was tilled soil. the only significant contributor to the concen Three benefits from using this plough after a tration of 1,4Cs in the Greenland Sea in 1988. surface contamination can be identified as 1) a the appearance of Chernobyl caesium in the considerable reduction in doserate over the intermediate water at 80 - 300 meters (Dahl surface, 2) a lower uptake of radioisotopes to gaard et al. b. 9.2) indicates a significant con plants and 3) a considerable reduction of re- tribution in surface water, having an age of suspension, as the contaminated soil, once only two years. The origin of this surface water buried, will not be resuspended in the follow was probably the Norwegian Coastal Current or ing tilling procedures. the West Spitzbergen Current. Equivalent mea The plough is to be used in connection with surements of technetium-99 from the European countcrmcasurcs after the Chernobyl accident. discharges during the 1970s and 1980s are consistent with a very high water renewal rate in the studied part of the Greenland Sea. Riso-R-624(EN) 47 Fid. 6.7.1. 48 Riso-R-624(EN) 7 Other Activities 7.1 Decontamination Strategies for 72 Photochemistry and Photophy- Urban Areas sics Studies at Gavle (Sweden) demonstrated that The general scope of the activity has been ex many urban surfaces, such as roof tiles and panded considerably. In particular, the techni concrete, have a considerable potential for ques of nanosecond laser flash photolysis in intercepting and retaining radiocacsium fallout combination with time-resolved absorption from the Chernobyl accident. spectroscopy on the one hand, and fluorescence The interception by such surfaces is not in lifetime spectroscopy on the other, have been itself surprising, since caesium (a cation) would added to the experimental facilities. This has be expected to ion exchange with sodium, po been possible through considerable support by tassium and calcium (also cations), which are the Danish Natural Science Research Council. known to occupy anionic adsorption sites on It is also the reason fcr a change of the name the surfaces of almost al! urban minerals. What of the group (previously Raman group). was surprising however, was the strong reten Most of the previous studies were continued. tion of absorbed caesium on these surfaces, They all concern investigations of the potential even after extensive decontamination treat energy surfaces of electronic excited states, or ments. (Roed ei al.. 9.2: Anderson. 9.3) free radicals of organic molecules of basic and The ratios of nuclide concentrations in run applied interest. All studies were carried out in off wa'cr. compared with those in rain water, close collaboration with Dr F.W.Langkilde, give an estimate of the various interception Royal Danish School of Pharmacy. potentials. Etcrnite. a common roofing material, 1,3.5-Hcxatriene (HT) and related com showed a high affinity, absorbing SOT. of the pounds arc still the most important area of re deposited material, whereas silicon-treated search. In particular, five full scale papers on surfaces had an uptake of only 50T>. spectroscopic and photochemical studies of HT, Shortly after deposition. 40-S0rr> of the both in solution and in the gas phase were initially deposited caesium remained on paved completed. New studies have been initiated on areas. Two years later. S-ZO'p was left, the specially synthesized HT which is "locked" at percentages depending strongly on traffic. A the central position and is therefore prevented portion of 20-70^0 remained on roofs. to isomerize. Work on the triplet state of A strategy for the decontamination of an stilbcnc continues. Both these projects were urban area was set up. It was found that the carried out in international collaboration with removal of trees and the decontamination of laboratories in Italy (Professor G. Orlandi) and gardens are efficient and inexpensive means of The Netherlands (Drs A.M. Brouwer and achieving very significant reductions in dose. HJ.C. Jacobs). Such measures would rate highly on a list of A study of intramolecular proton transfer priorities. Street cleaning is also cost-effective. was completed in collaboration with the In Although roofs arc important contributors to stitute of Physical Chemistry of the Polish dose, the cost of cleaning them is so great, that Academy of Sciences (Dr A. Mordzinski). roof decontamination would not rank highly on The benzyl radical, being of fundamental a priority scale. Walls contribute little to total interest in atmospheric and combustion chemi dose and arc expensive and difficult to clean. stry, was studied in collaboration with the Their decontamination would, therefore, carry a Industrial Chemistry Research Institute. Poland very low rating on a list of priorities. (Dr K. Bajdor). Riso-R-624(EN) 49 Macrocytic compounds of importance in mo nish National Agency of Industry and Trade as lecular switches were studied in collaboration an accredited Testing and Calibration Labora with CISM1, Copenhagen University (Professor tory with the registration No. 266. The accre K. Bechgaard). ditation was issued under the Danish Accre Collaboration with Dr O.S. Mortensen. ditation Scheme (in Danish: Dansk Akkredi Odense University, in the field of resonance terings Ordning), which is administered by the Raman spectroscopy continues. Danish Institute of Fundamental Metrology. International recognition of the Danish Accre ditation Scheme is assured through its mem 73 Rise High Dose Reference La bership of the Western European Calibration boratory (HDRL) Cooperation, WECC. This organization assures mutual recognition of certificates and reports which are issued by testing and calibration In October 1991, the Riso High Dose Refer laboratories, accredited in the member contries. ence Laboratory became recognized by the Da- Signatories of this WECC agreement are: Denmark Danish Accreditation Scheme France Bureau National de Métrologie, BNM Finland Centre for Metrology and Accreditation Germany Deutscher Kalibricrdicnst. DK.D Italy Scrvizio di Taratura in Italia. SIT Netherlands Ncdcrlandse Kalibratic Organisatie, NKO Switzerland Swiss Calibration Service. SCS Sweden Swedish Board for Technical Accreditation, SWEDAC United Kingdom National Measurement Acceptation Service, NAMAS The High Dose Reference Laboratory is standard can be chosen as the national stan working for the radiation processing industry. dard, but in order for it to be primary, its Its services include irradiation of dosimeters response must be derived from fundamental and samples to specified doses, the issue of physical constants. The HDRL does not main calibrated dosimeters, and measurements of tain its own primary standards in the field of absorbed dose in facilities and products. The radiation dosimetry. We must therefore look range of absorbed dose is specific for each elsewhere to calibrate our secondary standards, service, but in general, it is from one kGy and and we have chosen to go to the National Phy higher. Measurements and irradiations, at both sical Laboratory in England By this calibration cobalt-60 photon and 10 MeV electron facili - and by auditing the calibration - we may say ties, are covered by the services of the High that the HDRL dose measurements are trace Dose Reference Laboratory. During 1991 - able to the NPL. before and after the official accreditation was The High Dose Reference Laboratory ope issued - a total of 75 reports and 34 certifi rates according to a European standard: EN cates were issued. 45001. Genera] Criteria for the Operation of In order for a laboratory to obtain accredita Testing Laboratories, and to the OECD Rules tion, it must demonstrate that its measurements for Good Laboratory Practice. These documents are traceable to a national standard at the pri ?re part of the many standards and guidelines mary standard level. Some confusion exists that will harmonize European industry and about the standard hierarchy. Actually, any 50 Riso-R-624(EN) trade in preparation for the Single Market which will be in effect by 1993. Without accreditation, a calibration or testing laboratory may find it difficult to get its results and certificates recognized, so customers may therefore be reluctant to buy its services. It is, therefore, good for business to become accredited, and also good for the measure ments. All procedures and practices must to be reviewed and documented, uncertainties have to be accounted for and calibrations maintained. It all leads to better measurements and fewer mistakes, thereby providing assurance of the quality control of the laboratory. Industrial inadiation has continued on the 10 MeV electron accelerator. Products have been irradiated for sterilization of medical equip ment, modification of polymers, and to a limited extent, also for the decontamination of spices. Special products and samples have been irradiated both on the 10 McV accelerator, the 400 keV accelerator and on the cobalt-60 facilities. The 10 kCi facility located in the section for Plant Biology, had its eight sources replaced with new ones, which were made at Riso. The eight old sources were, as usual, transferred to the gamma cell in the Chemical Reactivity Section. A second gamma cell, which for many years has been on loan to the State Scrum Institute, was returned to Riso and is now installed in the hall in the Chemical Reactivity Section. This gamma cell (labelled No. 2) also had its source strength increased with the replacement of two sources. The closing of the Riso Hot Cell means that cobalt-60 sources or no longer be produced at Riso. It is possible to obtain new sources for Riso's gamma facilities abroad, but as the next source replacement is scheduled for 1996 or 1997, no details have yet been worked out. Riso-R-624(EN) 8 Large Facilities 8.1 10 McV Linear Electron 8.4 Open Top Chamber Facility Accelerator In collaboration with the National Environ The Riso linear accelerator was manufactured mental Research Institute and University of in 1975 by Haimson Research Corp. Electrons Copenhagen the Department operate a large are accelerated by an electromagnetic micro Open Top Chamber facility situated at Riso. wave field with a frequency of 2S56 MHz. The The facility consists of 19 large chambers (3.5 accelerator is used for radiation sterilization, meters in diameter) and 20 small chambers (1.5 plastic modification, food treatment, radiation meters in diameter). hardness testing, semiconductor modification The small chambers have been equipped and initialization of chemical processes in with lysimeters for water and nutrient balance kinetic investigations. Products are irradiated studies, and for measuring nutrient leaching on a conveyor belt with electrons striking from the soil profiles. above. Maximum product size is normally 80 x The chambers are used for short- and long- 60 x 303 (1 w h). but other sizes may be ac -term studies of the effects of air pollution on commodated. The maximum height depenJs on crop plants and trees. the product density. 8.2 Pilot Plant for Metal Extraction A complete and selfcontained pilot plant was established at Riso in 1981 initially to handle metal extraction under alkaline and neutral conditions from a variety of ore types and minerals. The heart of the plant is a 1200 m long pipe reactor which makes possible continuous treat ment of suspensions at 2S0*C and 100 bar. The pilot plant has since intermittently been used to implement our wet oxidation process on a semiindustrial scale. 8J Experimental Farm DYSKÆRGAARD is an experimental farm with approximately 120 hectares of arable land. The experimental farm is partly used for field experiments, and partly for grain and beef production. 52 Ris Anastasi, C, Bevenon, S., Ellermann, T., Dahlgaard, H. (1991). Variation in radionucli Pagsberg, P. (1991). Reaction of CH3 radi de loss rates from Baltic Mytilus edulis. In: cals with OH at room temperature and pres Heavy metak "n the environment. Vernet, sure. J. Chem. Soc. Faraday Trans. 87, 2325- J.-P. (ed.), (Elsevier, Amsterdam), (Trace 2329. metals in the environment, 1), 261-271. Anastasi, C, Broomfield, M., Nielsen, O.J., Draganic, I.G., Bjergbakke, £., Draganic, Pagsberg, P. (1991). Ultraviolet absorption Z.D., Sehested, K. (1991). Decomposition of spectra and kinetics of CH3S and CH2SH ra ocean waters by potassium-40 radiation dicals. Chem. Phys. Lett. 182, 643-648. 3800 Ma ago as a source of oxygen and Anastasi, C, Muir, D.J., Simpson, V.J., Pags oxidizing species. Precambrian Res. 52, berg, P. (1991). Spectrum and mutual kine 337-345. tics of HOCHiCH^O-, radicals. J. Phys. Draganic. Z.D., Negron-Mendoza, A., Sehe Chem. 95, 5791-5797." sted, K, Vujose\'ic, S.I., Navarro-Gonzales, Andersson, J., Sandstrom, O., Hansen, H.J.M. R., Albarran-Sanchez, M.G., Draganic, I.G. (1991). Elver (Anguilla anguilla L) stockings (1991). Radiolysis of aqueous solutions of in a Swedish thermal effluent - recaptures, ammonium bicarbonate over a large dose growth an • body condition. J. Appl. Ichthyol. range. Radial. Phys. Chem. 38, 317-321. 7, 78-89. Feely, M, McCabe, E., Kunzendorf, H. (1991). Bubrowski, K., Sciwneich, C, Holcman, J., The evolution of REE profilt; in the Galway Asmus, K.-D. (1991). OH radical induced granite Western Ireland. Irish J. Earth Sci. decarboxylation of methionine-containing 11, 71-89. peptides. Influence of peptide sequence and Glasby, G.P., Cullen, D.J., Kunzendorf, H, net charge. J. Chem. Soc. Perkin Trans. 2, Stuben, D. (1991). Marine manganese crusts 353-362. around New Zealand: A preliminary assess Bobrowski, K., Schoneich, C, Holcman, J., ment. N.Z. Oceanogr. Inst. Misc. Publ. (no. Asmus, K.-D. (1991). OH radical induced 106), 1-25. decarboxylation of gamma-glutamylmethio- Hamilton, T.F., Fowler, S.W., LaRosa, J., nine and S-alky'elutathione derivatives: Evi Holm, E., Smith, J.D., Aarkrog, A., Dahl dence for two different pathways involving gaard, H. (1991). Comparative study of plu C- and N-terminal decarboxylation. J. tonium and americium bioaccumulation from Chem. Soc. Perkin Trans. 2, 975-980. two marine sediments contaminated in the Bothmer, R. von, Salomon, B., Linde-Laursen, natural environment. J. Environ. Radioact. I. (1991). Cytogenetics in hybrids of Hor- 14,211-223. deum jubatum and H.tetraploidum with culti Hansen, H.J.M. (1991). Significant year-toyear vated barley (H. vulgare L.). Hereditas 114, variation of the response to radiation-in 4146. duced stress shown by gill fatty acid meta Bothmer, R. von, Jacobsen, N„ Baden, C, bolism in eels (Anguilla anguilla) captured Jørgensen, RB., Linde-Laursen, I. (1991). from the wild. Comp. Biochem. Physiol. C An ecogeographical study of the genus Hor- 100, 99-101. deum. (IBPGR, Rome) (Systematic and eco- Hickel, B., Sehested, K. (1991). Activation jeographic studies on crop genepools, 7), energies for the reactions 0"+H2 and 0~+D2 127. in aqueous solution. J. Phys. Chem. 95, Christensen, E. Ahrensburg, Kristensen^ H., 744-747. Hoborn, J., Miller, A. (1991). Radiation re Holcman, J., Bobrowski, K, Schoneich, C, sistance of microorganisms on unsterilized Asmus, K.-D. (1991). OH-induced oxidation infusion sets. APM1S 99, 620-626. of cyclo-Met-Mct. A search for a com- Risø-R-624(EN) 53 plexed OHradicaJ. Radiat. Phys. Chem. 37, types of Dasypyrum villosum (2x) and D. 473-478. breviaristutum (4x) from Greece. Hereditas Jakobsen, I. (1991). Carbon metabolism in 114. 237-244. myconhiza. Methods Microbiol. 23, 149- Linde-Laursen, I., Jensen, J. (1991). Genome 180. and chromosome disposition at somatic me- Jensen, E.S. (1991). Evaluation of automated taphase in a Hordeum x Psathyrosiachys analysis of l5N and total N in plant material hybrid. Heredity 66, 203-210. and soil. Plant Soil 133, 83-92. McLaughlin, W.L., Chen Yun-Dong, Soares, Jensen, E.S. (1991). Nitiogen accumulation and C.G., Miller, A., Van Dyk, G, Lewis, D.F. residual effects of nitrogen catch crops. Acta (1991). Sensitometry of the response of a Agric. Scand. 41, 333-344. new radiochromic film dosimeter to gamma Kjær, B., Haahr, V., Jensen, J. (1991). Asso radiation and electron beams. Nucl. Instrum. ciations between 23 quantitative traits and 10 Methods Phys. Res. A 302, 165-176. genetic markers in a bailey cross. Plant Miller, A. (1991). Maximum and minimum Breed. 106, 261-274. doses in gamma and electron irradiated pro Kldning, U.K., Sehested, K., Appelman, E.H. ducts. BetaGamma (no. 3/4) 6-9. (1991). Laser flash photolysis and pulse ra- Møller, S., Langkilde, F.W., Wilbrandt, R. diolysis of aqueous solutions of the fluoroxy- (1991). Sensitized triplet photochemistry of sulfate ion S04F~. Inorg. Chem. 30, 3582- E- and Z-l,3,5-hexatriene. J. Photochem. 3584. Photobiol. A 62, 93-106. Kldning, U.K., Sehested, K. (1991). The prima Negri. F., Orlandi, G., Brouwer, A.M., Lang ry process CI03~(+hv)->C10~+02 in the kilde, F.W., Møller, S., Wilbrandt, R. (1991). photolysis of aqueous GC>3~solutions. J. Lowest excited triplet state of 2,5-dimethyl- Phys. Chem. 95, 740-743. 1,3,5 hexatiiene: Resonance Raman specfa Kragh, K.M., Jacobsen, S., Dalgaard Mikkel and quantum chemical calcula'ions. J. Phys. sen, J., Nielsen, K.A. (1991). Purification and Chem. 95, 6895-6904. characterization of three chitinases and one Nielsen, O.J. (1991). Rate constants for the fl—1,3 glucanase accumulating in the medium gas-phase reactions of OH radicals with of eel! suspension cultures of barley (Hor- CH3CHF2 and CHCI2CF3 over the tempera deum vulgare L). Plant Set. 76. 65-77. ture range 295388 K.'Cheni. Phys. Lett. 187, Kunzendorf, H. (1991). Radioanalysis in geo 286-290. chemistry (book review). Lithos 27, 147-148. Nielsen, O.J., Munk, J., Locke, G., Wallington, Kunzendorf, H., Walter, P., Stoffers, P., T.J. (1991). Ultraviolet absorption spectra Gwozdz, R. (1990). Rare and precious ele and kinetics of the self-reaction of CH2Br ment geochemistry of sediments from the and CH7Br02 radicals in the gas-phase at uau Basin. Geol. Jahrb. D (1990) 92, 263- 27c, K. J" Phys. Chem. 95, 8714-8719. 277. Nielsen, O.J., O'Farrell, D.J., Treacy, J.J., Langkilde, FM, Wilbrandt, R., Møller, S., Sidebottom, H.W. (1991). Rate constants for Brouwer, A.M., Negri, F., Orlandi, G. (1991). the gas-phase reactions of hydroxyl radicals Resonance Raman and absorption spectro with tetramethyllead and tetraethyllead. scopy of the lowest triplet state of 1,3.5-he- Environ. Sci. Techno]. 25, 1098-1103. xatriene and deuterlated derivatives at 183 K: Nielsen, O.J., Sidebottom, H.W., Donion, M., Molecular struct jre in the Tj state. J. Phys. Treacy, J. (1991). An absolute- and ida- Chem. 95, 6884-6894. tive-rate study cf the gas-phase reaction of Larsen, E.T., Twesson, I.K.D., Andersen, S.B. OH radicals and CI atoms vvith n-alkyl ni (1991). Nuclear genes affecting percentage of trates. Chem. Phys. Lett. 178, 163-170. green plants in barley (Hordewn vulgare L.) Nielsen, O.J., Sidebottom, H.W., Donion, M., anther culture. Theoretical and Applied Ge Treacy, J. (1991). Rate constants for the netics 82,417-420. gasphase reactions of OH radicals and CI Linde-Laursen, '., Frederiksen, S. (1991). atoms with n-alkyl nitrites at atmospheric Comparison of the Giemsa C-bandcd karyo 54 Risø-R-624(EN) pressure and 298 K. Int. J. Chem. Kinet. 23. Sehested, K., Corfuzen, H., Holcman, J., 1095-1109. Fischer, CH., Hart, E.J. (1991). The pri Nies, H., Albrecht, H., Rechenberg, V., Goron- mary reaction in the decomposition of ozone cy, I., Dahlgaard, H., Weiss, D., Brugmann, in acidic aqueous solutions. Environ. Set. L. (1990). Intercomparison of sediment Techno!. 25, 1589-1596. sampling techniques by means of radionucli Solar, S., Getoff, N., Sehested, K., Holcman, J. de and heavy metal analysis. Dtsch. Hydrogr. (1991). Pulse radiolysis of pyridinecarboxylic Z. 43, 27-53. acids in aqueous solution. Radiat. Phys. Solan, C, Dahlgaard, H. (1991). Accumula Chem. 38, 323-332. tion of metal radiotracers by Mytilus edulis. Sommer, SG, Jensen, E.S. (1991). Foliar ab Mar. Ecol. Prog. Ser. 70 (no. 2),' 165-174. sorption of atmospheric ammonia by ryegrass Nybroe, O., Johansen, A., Laake, M. (1990). in the field. J. Environ. Qual. 20, 153-156. Enzyme-linked immunosorbent assays for Stiiben, D, Glasby, G.P., Kunzendorf, H., detection of Pseudomonas fluorescens in Lange, H., Chen, S. (1991). Distribution, sediment samples. Lett. Appl. Microbiol. 11, morphology, and geochemistry of manganese 293-296. crusts and nodules from the Philippine Sea. Pagsberg, P., Sriuba, B., Ratajczak, E., Sille- Mar. Min. 10, 73-93. sen, A. (1991). Spectrokinetic studies of the Sørensen, P., Jensen, E.S. (1991). Sequential gas phase reactions NH2 + NOx initiated by diffusion of ammonium and nitrate from soil pulse radiolysis. Acta Chem. Scand. 45, 329- extracts to a polytetrafluoroethylene trap for 334. 15N determination. Anal. Chim. Acta 252, Pongsakul, P., Jensen, E.S. (1991). Dinitrogen 201-203. fixation and soil N uptake by soybean as Wallington, T.J., Nielsen, O.J. (1991). UV ab affected by phosphorus availability. J. Plant sorption spectra and kinetics of the self reac Nutr. 14, 809-823. tion of CFC12CH202 and CF2C1CH202 radi Puteanus, D., Glasby, G.P., Stoffers, P., Kun- cals in the gas phase at 298 K. Int. J. Chem. zendorf, H. (1991). Hydrothermal iron-rich Kinet. 23, 785-798. deposits from the Tcahitia-Mehitia and Mac- Wallington, T.J., Nielsen, O.J. (1991). Pulse donald hot spot areas, Southwest Pacific. radiolysis study of CF3CFH02 radicals in the Mar. Geol. 98, p. 389-409. gas phase at 298 K. Chem. Phys. Lett. 187, Rasmussen, S.K., Welinder, K.G., Hejgaard, J. 33-39. (1991). cDNA cloning, characterization and Øhlenschlæger, Af, Gissel-Nielsen, G. (1991). expression of an endosperm-specific barley Differences in the ability for barley and rye peroxidase. Plant Mc!. Biol. 16, 317-327. grass varieties to absorb caesium through the Rosendahl, L, Glenn, A.R., Dilwonh, M.J. roots. Acta Agric. Scand. 41, 321-328. (1991). Organic and inorganic inputs into legume root nodule nitrogen fixation. In: Biology and biochemistry of nilrogen fixa 9.2 Proceedings (incl. Abstracts) tion. Dilworth, M.J., Glenn, A.R. (eds), (El sevier, Amsterdam) (Studies in Plant Science, Aarkrog, A. (1991). Source terms and invento 1), 259-291. ries of antropogenic radionuclides. In: For- Schonbacher, H., Coninckx, F., Miller, A., skarkurs i radioekologi. Forskarkurs i radio- Kruska, G., Wulf, I. (1991). Colour dose- ekologi, Lund, April 15-26, 1991. (NKS, meters for high level radiation dosimetry. Lund University), 17 p Radiat. Prot. Dosim. 34, 311-314. Andersen, L. (1991). Mlo agg.es'siveness in Seberg, O., Frederiksen, S., Baden, C, Linde- European bar'ey powdery mildew. In: Inte Laursen, I. (1991). Peridictyon, a new genus grated control of cereal mildews: Virulence from the Balkan peninsula, and its relation patterns and their change. 2nd European ship with Festucopsis (Poaceae). Willdenowia Workshop on Integrated Control of Cereal 21, 87-104. Mildews, Riso, January 23-25, 1990. Jør- Risø-R-624(EN) 55 gensen, J. Helms (ed.). (Riso National La wich, September 10-13, 1991. Kershaw, P.J., boratory. Roskilde), 1S7-196. Woodhead, D.S. (eds), (Elsevier Applied Andersen, L, Helms Jørgensen, J. (1991). Mlo Science, London), 365. aggressiveness in barley powdery mildew. Egsgaard H., Larsen, E., Solgaard, P., Vin Nord. Jordbrugsforskn. 73 (no. 3), 538. ther Kristensen, L., Carlsen, L. (1991). Bertelsen, F., Jensen, ES (1991). Turnover of Flame studies on the VG plasmaquad. In: 15N-labelled nitrate with special emphasis on Extended abstracts of papers presented at the denitrification in the field. In: Stable isotopes 12th international mass spectrometry con in plant nutrition, soil fertility and environ ference. 12th International mass spectrometry mental studies. International symposium on conference, Amsterdam, August 26-30, the use of stable isotopes in plant nutrition, 1991. (IMSC, Amsterdam), 265. soil fertility and environmental studies, Engvild, K.C. (1991). Do plants contain two Vienna, October 1-5, 1990. (IAEA, Vienna) auxin types, endogenous herbicides and (STI-PUB-845), 336-338. growth promotors? Physiol. Plant. 82 (no. 3), Brodersen, K., Nilsson, K. (1991). Pores anc B8. cracks in cemented waste and concrete. In: Gwozdz, R., Hansen, H.J., Rasmussen, K.E., EMRS 1991 fall meeting. Symposium D: Kunzendorf, H. (1991). Instrumental neutron Chemistry of cements for nuclear applica activation analysis of samples with weights tions. Program. EMRS 1991 fall meeting. from micrograms to hectograms. In: 8th In Strasbourg, November 4-8, 1991. (Commis ternational conference: Modern trends in sion of the European Communities, Stras activation analysis. Book of abstracts. bourg) Session V, 2 p. MTAA 8, Vienna, September 16-20, 1991. Brown, J.K.M., Jørgensen, J. Helms (1991). A (ASER, Vienna), 1 p. catalogue of mildew resistance genes in Eu Hansen, H.J.M. (1991). Statistical treatment of ropean barley varieties, in: Integrated control data. In: Forskarkurs i radioekologi. Forskar of cereal mildews: Virulence patterns and kurs i radioekologi, Lund, April 15-26, their change. 2nd European workshop on in 1991. (NKS, Lund University), 11 p. tegrated control of cereal mildews, Riso. Holm, £., Roos, P., Persson, R.B.R., Bojanow- January 23-25, 1990. Jo-genscn, J. Helms ski, R., Aarkrog, A., Nielsen, S.P., Livings (ed.), (Riso National La'o.vatory. Roskilde), ton, H.D. (1991). Radiocaesium and pluto 263-286. nium in atlantic surface waters from 73 deg. Dahlgaard, H. (1991). Marine radioecology. In: N to 72 deg. S. In: Radionuclides in the Forskarkurs i radiockologi. Forskarkurs i study of marine processes. International radioekologi, Lund, April 15-26, 1991. symposium on radionuclides in the study of (NKS, Lund University), 12 p. marine processes, Norwich, September 10- Dahlgaard, //., Chen, Q.J., Nielsen, S.P. 13, 1991. Kershaw, P.J., Woodhead, D.S. (1991). Radioactive tracers in the Greenland (eds), (Elsevier Applied Science, London), sea. In: Radionuclides in the study of marine 3-11. processes. International symposium on radio Hovmøller, M.S., Østergård, H. (1991). Mo nuclides in the study of marine processes, delling the dynami s of virulence genotype Norwich, September 10-13, 1991. Kershaw, frequencies in barley powdery mildew popu P.J., Woodhead, D.S. (eds), (Elsevier Applied lations in relation to selection and recom Science, London), 12-22. bination. In: Integrated control of cereal Dahlgaard, //., Nies, H., Weers, A.W. van, mildews: Virulence patterns and their Guegueniat, P., Kershaw, P. (1991). Studies change. 2nd European workshop on inte on the transport of coastal water from the grated control of cereal mildews, Riso, Janu English Channel to the Baltic Sea using ra ary 23-25, 1990. Jørgensen, J. Helms (ed.), dioactive tracers. (MAST project). In: (Riso National Laboratory, Roskilde), 115— Radionuclides in the study of marine proces 121. ses. International symposium on radionucli Jensen, E.S. (1991). Kvælstofbinding hos des in the study of marine processes, Nor markært og indflydelsen af ærtedyrkning på 56 Risø-R-624(EN) kvælstofomsætningen i jorden. Noid. Jord- tics VI. Volume 1. Short papers. 6th Interna bnigsforskn. 73 (no. 3). 422. tional barley genetics symposium, Helsing Jensen, ES. (1990). Kvælstofbinding hos borg, July 22-27, 199L Munck, L., Kirke markært og indflydelsen af ærtedyrkning på gaard, K., Jensen, B. (eds).(Munksgaard, kvælstofomsætningen i jorden. Våxtodling Copenhagen), 335-336. 23, 63-68. Jørgensen, J. Helms (1991). Powdery mildew Jensen, ES. (1991). Biologisk kvælstofbinding resistance genes Mla22 and Mla23 in barley. i jordbrugets planteproduktion. Nord. Jord- In: Barley genetics VI. Volume 1. Short brugsforskn. 73, 223. papers. 6th International barley genetics Jensen, ES (1991). Decomposition of 15N-la- symposium, Helsingborg, July 22-27, 1991. belled mature pea residues in the field. In: Munck, L., Kirkegaard, K., Jensen, B. (eds), Humus et planta. Proceedings. 10th Interna (Munksgaard, Copenhagen), 596-598. tional symposium on humus et planta, Jørgensen, J.H. (1991). Mutation studies on Prague, August 19-24, 1991. (Research In cereal disease resistance. In: Plant mutation stitute for Crop Production, Prague), 79. breeding for crop improvement. Volume 2. Jensen. E.S., Brink, M. (1991). Automated International symposium on the contribution analysis of N and total N in plant material of plant mutation breeding to crop improve and soil. In: Stable isotopes in plant nutrition, ment, Vienna, June 18-22, 1990. (IAEA, soil fertility and environmental studies. Inter Vienna). 81-91. national symposium on the use of stable iso Kovdcs, A., Mehta, K.K., Miller, A. (1991). topes in plant nutrition, soil fertility and Characterization of linear electron accelera environmental studies, Vienna, October 1-5, tors using reference and routine dosimetry 1990. (IAF.A, Vienna) (STI-PUB-845). methods. In: High dose dosimetry for radia 54-55. tion processing. International symposium on Jensen, H.P., Jensen, J., Helms Jørgensen, J. high dose dosimetry for radiation processing, (1991). On the genetics of Laevigatum pow Vienna, November 5-9, 1990. (IAEA, dery mildew resistance in barley. In: Barley Vienna), 371-384. genetics VI. Volume 1. Short papers. 6th Kunzendorf, H, Schrøder, N. (1991). Marine International barley genetics symposium, geochemical surveying of the ocean floor by Helsingborg, July 22-27, 1991. Munck, L., a towed gamma sonde. In: The 2nd marine Kirkegaard, K., Jensen, B. (eds), (Munks geological conference. The Baltic. Abstracts gaard, Copenhagen), 593-595. of papers. The 2nd marine geological confe Jensen, HP., Jørgensen, J. Helms (1991). Re rence. The Baltic, Rostock - Warnemiinde, sistance to powdery mildew in spring barley October 21-26, 1991. (Institut fur Meeres- varieties and their distribution in Denmark kunde, Warnemunde), 1 p. 1977 to 1989. In: Integrated control of cereal Kunzendorf, H, Schrøder, N. (1991). Gcoche- mildews: Virulence patterns and their change. mical monitoring on the seafloor by a towed 2nd European workshop on integrated control gamma sonde. In: 2nd International sympo of cereal mildews, Riso, January 23-25, sium on environmental geochemistry. Ab 1990. Jørgensen, J. Helms (ed.), (Riso Natio stracts. 2nd International symposium on nal Laboratory, Roskilde), 257-262. environmental geochemistry, 3rd Internatio Jensen, J. (1991). New high yielding, high nal symposium on environmental geochemi lysine mutants in ba;ley. In: Plant mutation stry and health, 9th European meeting of the breeding for crop improvement. Volume 2. Society for Environmental Geochemistry and Internationa! symposium on the contribution Health, Uppsala, September 16-19, 1991. of plant mutation breeding to crop improve Selinus, O. (ed.), (Sveriges Geologiska Un- ment, Vienna, June 18-22, 1990. (IAEA, dersokning, Uppsala) (Sveriges Geologiska Vienna), 31-41. Undcrsokning. Rapporter och Meddelanden, Jensen, J., Holm-Jensen, AG., Johansen, H.B., 69). 2 p. Giese, H. (1991). Linkage between RFLP Langkilde, F.W., Wilbrandi, /?., Brouwer, A.M., markers and yield in barley. In: Barley gene Negri, F., Orlandi, G. (1991). Molecular Riso-R-624(EN) 57 structure of stilbcne in the Tl state. Time- 2nd European work-shop on integrated con resolved resonance Raman spectra of trans- trol of cereal mildews, Riso, January 23-25, stilbene and isotopomcrs. In: 5th International 1990. Jorgensen, J. Helms (ed), (Riso Na conference on time-resolved vibrational tional Laboratory, Roskilde) 55-65. spectroscopy. Abstracts. 5th International Sielsen, K., Pedersen, A., Jensen, E.S., Kon conference on timeTesoIved vibrational spec- drup, J. (1991). Net protein utilization versus trosocpy, Tokyo, June 2-7, 1991. Takahashi. protein synthesis efficiency. Clin. Nutr. Spec. H. (ed.j. (Waseda University, Tokyo), 29. Suppl. 2 10, 30. Linde-Laursen, I. (1991). Kan de båndfarvede Sielsen, K. Pedersen, A., Jensen, E.S., Kon kromosomer bruges som artskendetegn i dyr drup, J. (1991). Different proteins have dif ket og vild byg?. In: Biodiversitet. Artsbe- ferent effects on protein synthesis and de grebet i teori og praksis. Symposium om gradation. Clin. Nutr. Spec. Suppl. 2, 10, 6. artsbegrebrt. Kobenhavn, November 22-23, Sielsen, O.J. (1991). Kinetic study of the 1991. Redsted Rasmussen, A. fed.), (Forlaget reactions of OH radicals with CH3CHF1 Steenstrupia. Kobenhavn), 28-29. (HFC-152a) and CHC12CF3 (HCFC-123)" Linde-Laursen, /., Boihmer, R. von (1991). In: Kinetics and mechanisms for the reac Barley chromosome 6 retained specifically in tions of halogenated organic compounds in hypoploid hybrids of a chromosome-elimi the troposphere. STEP-HALOCSIDE/ nating interspecific cross. In: Barley genetics AFEAS workshop, Dublin, May 14-16, VI. Volume 1. Short papers. 6th International 1991. (University of Dublin, Dublin), 17-26. barley genetics symposium, Helsingborg, July Sielscn, O.J., Donlon, M., Sidebottom, H.W. 22-27, 1991. Munck, L., Kirkegaard, K., Treacy, J. (1991). Reactions of OH radicals Jensen, B. (eds), (Munksgaard. Copenhagen), with n-alkyl nitrates and nitroalkanes. A 77-79. contribution to subproject LACTOZ. In: Linde-Laursen, I., Jensen. J. (1991). Proposal Transport and transformation of pollutants in for new designations of chromosome arms the troposphere. EURO-TRAC symposium and positions of chromosomal markers. In: 90, Garmisch-Partenkirchen, April 2-5, Barley genetics VI. Volume 1. Short papers. 1990. Borrell, P., Borrell, P.M., Seiler, W. 6th International barley genetics symposium. (eds), (SPB Academic Publishing, The Helsingborg, July 22-27, 1991. Munck. L., Hague), 407-411. Kirkegaard. K., Jensen, B. (eds). (Munks Sielsen. S.P. (1991). Compartmental modelling gaard, Copenhagen). 287-289. in radioecology. In: Forskarkurs i radioeko- Lorenzcito, P., Daenner, W., Chazalon. M.. logi. Forskarkurs i radioekologi, Lund, April Bjergbakke, E., Zaban, T. (1991). Radiolysis 15-26, 1991. (NKS, Lund University), 11 p. in EC aqueous lithium salt driver blanket. In: Sielsen, S.P. Kohler, //., Peterson, S.-R. Fusion technology 1990. Vol. 1. 16th Sym (1991). Testing of models for the grass- posium on fusion technology, London. Sep cow-milk pathway. In: BIOMOVS on the tember 3-7, 1990. Keen, B.E., Huguet, M.. validity of environmental transfer models. Hemsworth, R. (cds). (North-Holland, Am Proceedings. BIOMOVS symposium, Stock sterdam) (SOFT 16), 993-997. holm, October 8-10, 1990. (Swedish Radia Miller, A. (1991). Role of dosimetry in quality tion Protection Institute, Stockholm), 15-28. control. In: High dose dosimetry for radiation Sielsen, T., Ptlegaard, K, Jensen, A.B. (1991). processing. International symposium on high Sources of polycyclic aromatic hydrocarbons dose dosimetry for radiation processing. at an international airport. In: 13th Interna Vienna, November 5-9, 1990. (IAEA, tional symposium on polynuclear aromatic Vienna), 37-43. hydrocarbons. Program and abstracts. 13th Munk, L, Jensen, H.P., Jørgensen, J. Helms International symposium on polynuclear aro (1991). Virulence and disease severity of matic hydrocarbons, Bordeaux, October 1-4, barley powdery mildew in Denmark 1974- 1991. (Universilé de Bordeaux, Bordeaux) 1989. In: Integrated control of cereal mil Paper OC55. dews: Virulence patterns and their change. 58 Risø-R-624(EN) Nielsen, J., Pdegaard, K. (1991). Forekomst af of the European Communities. EUR-13013- og kilder til luftforurening med PAH ved (v.l), 433-450. Kobenhavns lufthavn. In: 4th Nordic sympo Roed, J., Jacob, P. (1990). Deposition on sium on organic pollutants. Soro. September urban surfaces and subsequent weathering. 8-11, 1991. (Danmarks Tekniske Hojskole. In: Proceedings of the seminar on methods Grundvandscentret, Lyngby), p. 40. and codes for assessing the off-site conse Pedersen, L.H (1991). Characterization and quences of nuclear accidents. Preprint. Volu partial purification of the 1,3-B-glucan me 1. Seminar on methods and codes for as synthase from barley leaves. (Abstract 571). sessing the off-site consequences of nuclear Plant Physiol. Suppl. 96 (no. 1), 90. accidents, Athens, May 7-11, 1990. Com Petersen, L. (1991). Application of RFLP mission of the European Communities. markers in backcross breeding. In: Barley EUR-I30l3(v.l), 335-356. genetics VI. Volume 1. Short papers. 6th Roed, J., Sandalls, J. (1990). Decontamination International barley genetics symposium, in the urban area. In: Proceedings of the Helsingborg. July 22-27, 1991. Munck, L., seminar on methods and codes for assessing Kirkegaard, K., Jensen, B. (eds). (Munks the off-site consequences of nuclear acci gaard, Copenhagen), 344-346. dents. Preprint. Volume 1. Seminar on me Pdegaard, K. (1991). Monitoring of particulate thods ana codes for assessing the off-site fall-out during exploration work at a niobium consequences of nuclear accidents, Athens, mineralization in Greenland. In: Heavy May 7-11, 1990. Commission of the Euro metals in the environment. Vol. 1. Interna pean Communities. EUR-13013, 373-384. tional conference on heavy metals in the Schroder, N., Kunzendorf, H. (1991). New environment, Edinburgh, September 1991. tools in marine mapping. In: The 2nd marine Fam,~r, J.G. (cd.), (CEP Consultants Ltd., geological conference. The Baltic. Abstracts Edinburgh), 216-219. of papers. The 2nd marine geological confe Rasmussen, S.K., Joi.onsson. A., Rasmussen, rence. The Baltic, Rostock - Warnemiinde, HN, Timlade, B. (19^1). Molecular analysis October 21-26, 1991. (Institut fur Meeres- and cloning of baTley peroxidase genes. In: kunde, Warnemunde), 1 p. Biochemical, molecular, and physiological Skou. J.P. (1991). Bevaring og dokumentation aspects of plant peroxidases. 2nd Internatio af den arvelige variation i planter og plante- nal symposium on plant peroxidases, Lublin, patogener. II. Plantepatogener. Nord. Jord- August 1990. Lobarzewski, J.. Greppin, H„ brugsforskn. 73, 254. Penel, C, Gaspar. T. (eds). (Université de Skou, J.P. (1991). Forædling for resistens mod Geneve. Laboratoire de Biochimie ct Physio stribesyge i vårbyg (Drechslera graminea). logic Végctales, Geneve), 21-29. Nord. Jordbrugsforskn. 73, 696. Roed, J., Andersson, K., Sandalls, J. (1991). Skytte Jensen, B. (1991). The formation of Reclamation of nuclear contaminated urban solid solutions as an important retardation areas. In: BIOMOVS on the validity of envi mechanism. In: Chemistry and migration ronmental transfer models. Proceedings behaviour of actinides and fission products in BIOMOVS symposium, Stockholm, October the geosphere. Abstracts. 3rd International 8-10, 1990. (Swedish Radiation Protection conference on chemistry and migration be Institute, Stockholm). 157-167. haviour of actinides and fission products in Roed, J., Goddard, A.J.H. (1990). Ingress of the geosphere, Jerez de la Frontera, October radioactive material into dwellings. In: Pro 21-25, 1991. (Migration 91. CIEMAT, ceedings of the seminar on methods and Madrid), 259. codes for assessing the off-site consequences Wilbrandt, R., Møller, S., Langkilde, F.W., of nuclear accidents. Preprint. Volume 1. Brouwer, A.M., Negri, F., Orlandi, G. Seminar on methods and codes for assessing (1991). The potential energy surface of the the off-site consequences of nuclear acci lowest excited triplet state of 1,3,5-hexatri- dents, Athens, May 7-11, 1990. Commission ene. In: Abstracts of invited lectures and oral and poster contributions. 15th International Risø-R-624(EN) 59 conference on photochemistry, Paris. July 28 Andersson, KG. (1991). The characterization - August 2, 1991. Kossanyi. J. (cd.). (Inter and removal of Chernobyl debris in garden national Scientific Committee, Paris). soils. Riso-M-2912. 26 p. 0/83-0/86. Berkel. B. van, Buchwald, K., Burbridge, P., Wilbrandi, R, Moller. S.. Langkilde. FW.. Danker*. N, Feige. M., Fleet. DM.. Hallers. Brouwer. AM., Negri, F, Orlandi, G. (1991). C. ten, Jensen, A., Olesen, H-J. (eds) The potential energy surface of the Tj state (1991). En fælles fremtid for Vadehavet. En of 1,3,5-hexatrienes and methylated deriva rapport fra Verdens Naturfonden. Dansk tives: A survey of present knowledge. In: 5th resumé. (World Wide Fund for Nature, Hu International conference on time-resolved sum), 7 p. vibrational spectroscopy. Abstracts. 5th Inter Berkel, B. van, Buchwald, K., Burbridge, P., national conference on time-resolved vibra Dankers, N., Feige, M., Fleet, DM., Hallers, tional spectroscopy. Tokyo. June 2-7. 1991. C. ten. Jensen, A., Olesen, H-J. (eds) Takahashi, H. (ed.), (Waseda University, (1991). The common future of the Wadden Tokyo), 85. Sea. A report by the World Wide Fund for Nature. (World Wide Fund for Nature, Hu sum), 64 p. 9.3 Research Reports Brodersen. K.. Nilsson, K. (1991). Mechanisms and interaction phenomena influencing re Aarkrog. A.. Bøtter-Jensen, L, Chen Qing leases in a low- and medium-level waste Jiang, Dahlgaard, H, Hansen, H., Holm, £., disposal system. Task 3: Characterization of Lauridsen, B., Nielsen. S.P., Søgaard-Han radioactive waste forms. A series of final sen, J. (1991). Environmental radioactivity in report (19S5-89). no. 31. EUR-13662, 92 p. Denmark in 1988 and 1989. Riso-R-570, Chen. Qing Jiang. Aarkrog, A., Nielsen, S.P., 213 p. Dahlgaard, H, Nies, H, Yu Yixuan. Man Aarkrog, A., Nielsen, S.P., Holm, E., Øhlen• drup, K. (1991). Determination of plutonium schlæger, M., Bøtter-Jensen, L, Chen Qing in environmental samples by controlled Jiang (1991). Terrestrial environment. A: valence in anion exchange. Riso-M-2856, Dynamic models of the human food chain 17 p. and B: Determination of less well-known Dahlgaard, H. Aarkrog, A., Nielsen, S.P., long-lived radionuclides. Final report. In: Holm, E-, Hansen, H., Chen, Qing Jiang Radiation protection programme. Progress (1991). Marine environment. A: Experimen report 1985-89. Volume irEUR-13268(v.l). tal studies (turnover of radionuclides in bio- 577-588. indicators). B: Field studies (North Atlantic Aarkrog, A., Hansen, H., Bøtter-Jensen. L, Region - Baltic Sea), and C: Thule studies. Nielsen, S.P.. Clausen, J. (1991). Radioakti Final report. In: Radiation protection pro viteten i Risoområdet juli-december 1990. gramme. Progress report 1985-89. Volume (Radioactivity in the Riso district July-De 1. EUR-13268(v.l)r 589-602. cember 1990). Riso-I-538. 21 p. Desmet, G. (ed.), Aarkrog, A., Cunningham, Aarkrog, A., Hansen, H, Bøller-Jensen, L, J.D., Grauby, A., Iranzo-Gonzales, £., Bua- Nielsen, S.P., Clausen, J. (1991). Radioakti des, M. (1991). Improvement of practical viteten i Risoområdet januaT-juni 1991. (Ra countcrmeasurcs: The agricultural environ dioactivity in the Riso district January-June ment. Post-Chernobyl action. Final report. 1991). Riso-I-571(EN), 22 p. EUR-12554, 198 p. Andersen, A., Jensen, ES., Haahr, V. (1991). Ellermann, T. (1991). Atmospheric CCI3 de- Stofproduktion og kvælstofudnyttelse i sæd grada-tion. A spectrokinetic laboratory study skifter med vinter- og vårformer af byg, of CC13 reactions by pulse radiolysis. raps, hvede og rug. Delrapport. Riso-I- Riso-M-2932, 172 p. 585(DA), 16 p. 60 Risø-R-624(EN) Gjorup, HL.. Hedemann Jensen, P.. Roed. J-, Smith AM.. Young. D.. Andersson. KG. Hetkel Vinther. F. (1991). Experimental and Gjorup. H.J.. Prip. H. Roed, J., Bennet, S.L. modelling approach to assess indoor doses in Eggieton, AEJ. Sandalls. FJ. (1991). Im urban agglomerations and evaluation of the provement of practical countermeasures: The decontamination through run-off of deposited urban environment. Post-Chernobyl action. material. Final report. In: Radiation protec Final report. EUR-12555, 311 p. tion programme. Progress report 19S5S9. Ølilenschleeger. M. (1991). The transfer of Volume 3. EUR-l326S(v.3). 3061-3072. radionuclides in the terrestrial environment. Kumendorf, H, Hansen. X.. Jensen. P.K. Riso-M-2934, 125 p. (1991). Temperature time variations in sedi Ølilenschleeger. M. (1991). Root absorption ments from the central trough area and the factors for varieties of crop species. In: Danish subbasin evaluated by fission-track Desmct, G. (ed.). Aarkrog. A., Cunningham. studies of cuttings from selected drill holes. J.D.. Grauby. A.. Iranzo-Gonzales, E., Bua- Riso-M-2935, 34 p. des, M., Improvement of practical counter- Melin. J., Backe, S., Erixon. O.. Jolmsson. B.. measures: The agricultural environment. Roed, J. (1991). Sanering efter reakiorolyc- Post-Chemobyl action. Final report. EUR- kan i Tjernobyl. Referat från en resa till 12554, 68-79.' Sovjet den 9-21 september 1990. SSI-R-91- 03, 55 p. Neumann, G. Notter, M., Dahlgaard. H. 9.4 Other publications (1991). Bladder-wrack (Fucus vesiculosus L.) as an indicator for radionuclides in the Bertelsen, F. (1991). Denitrifikation og bælg- environment of Swedish nuclear power plantedyrkning. Ph.D. Thesis. (Forsknings plants. (Swedish Environmental Protection center Risø. Sektionen for Plantebiologi, Agency, Soma. 1991) (Swedish Environmen Roskilde), 72 p. tal Protection Agency Report 3931). 35 p. Bohr, J., Skytte Jensen. B., Egsgaard, H, Nielsen, O.J., Sidebottom, H.W. (1991). Larsen. E. (1991). Buckminsterfulleren - en Atmos-pheric chemistry of nitrogen con ny slags kulstof. Risonyt, no. 4. 2-3. taining species. In: EUROTRAC (a EUREKA Brøns. P., Hansen. H. Andersen. E. (1991). environmental project) annual report 1990. Vor radioaktive klode 3. Naturlig radioakti Part 8. LACTOZ. (EUROTRAC. Garmisch- vitet i hverdagen. Nat. Verden, no. 5, 193- Paricnkirchcn), 160-170. 208. Nielsen, S.P., Øhlenschlæger, M. (1991). Strå- Brøns, P., Hansen. H, Andersen. E. (1991). lingsdoser fra forurenede levnedsmidler efter Vor radioaktive klode 5. Nedfald fra kernc- uheld på et atomkraftværk. Riso-M-2925, våbenforsog. Nat. Verden, no. 8, 313-320. 29 p. Gissel Nieben, G. (1990). Planteproduktion og Nielsen, T., Pilegaard, K., Lohse. C, Palmgren etik. In: Er hjertet trumf? Temaer i en bio Jensen, F. (1991). DCAR (Danish Centre for teknologisk debat. Pedersen. J. (ed.), (For Atmospheric Research) TOR measurements. laget PERA, Roskilde), 58-62. In: EUROTRAC (a EUREKA environmental Gissel-Nielsen, G. (1991). Dansk landbrug og project) annual report 1990. Part 9. TOR. miljo 1990. Tolvmandsbladct, no. 5, 24. (EUROTRAC. Garmisch-Partcnkirchcn). 56. Hansen, H (1991). De dode hummere - tre år Roed, J., Gjorup, H.L. (1991). Design and senere. Hvorfor præsenterer Miljøstyrelsens development of a skim and burial plough for rap|K>rt Vandmiljo-90 ikke udviklingen sag reclamation of contaminated land. In: Radia ligt?. Ingcnioren 17, no. 22, 8. tion protection programme. Progress report Hedemann Jensen, P., Hansen, H. (1991). 1985-89. Volume 1. EUR-13268, 999-1002. Tjernobyl - 5 år efter. Jyllandsposten, 26 Sinnaex'e, J., Olasi, M. (eds). Cremers, A., april. Preier, P. de, Elsen, A., Luyien, S.. Maes. A., Jakobsen, I. (1991). Mykorrhizasvampe og Sweeck, L, Gallagher, S., Hadden, R., Mel- planter samarbejder om at skaffe næring. vin, MA., McFadzean, S., Puierson, R.. RisoNyt. no. 4. 4-5. Rise-R-624(EN) 61 Jensen. J. (1990). Are powdery mildew resist Nørgaard Rasmussen. H. (1991). Oprensning ance loci Ml-p and ml-d on barley chromo og sekventcring af peroxidase cDNA-kloncr some 5?. Barley Genet. Newslett. 19. 27-32. fra bygblade. (Danmarks Tekniske Højskole. Jensen, J. (1990). Coordinator's report: Chro Afdelingen for Biokemi og Ernæring, Lvng- mosome 5. Barley Genet. Sewslett. 19. 74- by), 104 p. 77. Pearson Jr.. F.J., Haug. A. (1990). UTTLE Jensen. E.5. (1990). Efterafgrøde kan hjælpe på JOE. An expert system to support geochemi ærteeffekten. Landsbladet Mark. no. 7. 17- cal modelling. Part of final report for con 21. tract F11W-0079-DK. Geochemical data Jensen, ES. (1991). Om efterafgrøder og bases. (Risø National Laboratory. Chemistry kvælstof. Agrologisk Tidskrift om Markbmg. Section, Environmental Science and Techno no. 11, 33-35. logy Department, Roskilde). Johansson, A. (1991). Kloning og sekventcring Pilegaard. K. (1991). Øget viden om luftforu af en frospecifik byeperoxidase BP 1. (Ko rening med kvælstofforbindelser. Risonyt, benhavns Universitet, Kobenhavn) 75 p. no. 1. 6-7. Justesen, A. Fejer. (1991). Restriction Frag Pilegaard. K., Rasmussen, L (1991). Nedfaldet ment Length Polymorphism og Random Am af tungmetaller i Danmark. Milt ved analyse plified Polymorphic DNA som markorcr til af mos. Nat. Verden, no. 6, 238-248. kortlægningsbascret kloning i Erysiphe gra- Postma. J.G., Rosendahl, L. (1990). Nodule minis f.sp. hordei. (Institut for Økologi og metabolism and nitrogen transport in a su- Molekylærbiologi, Sektionen for Genetik. pernodulating non-fixing and a non-noduia- Den Kgl. Veterinær- og Landbohøjskole. ting mutant of pea (Pisum satiwm L.). In: Frederiksberg). 81 p. Mutants of Pisum sativum (L.) altered in the Jørgensen, J. Helms. (1990). Coordinator's symbiosis with RJtizobium leguminosarum. report: Discase and pest resistance genes. Postma. J.G.. (ed.) (Rijksunivcrsitcit Gronin Barley Genet. Ncwslctt. 19. 82-86. gen. Groningen), 109-122. Jørgensen. J. Helms. (1991). Mechanism of Skou. J.P. (1990). Nye danske navne på syg Mlo resistance to barley powdery mildew. domme. Mcdd. Plantepatologisk Nomenkla Sver. Utsadcsforcn. Tidsk. 101. 80-84. turudvalg no. 12, 1-6. KunzendorJ, H. (1991). Havbundens forunder Skou. J.P. (1991). Spireskadcnde svampe og lige mincralvcrden. Risonyt. no. 3. 8-9. deres betydning i vårbyg i Danmark. Tidsskr. Nielsen, KA. (1991). Establishment and bio Landokonomi 178, 123-141. chemical characterization of embryogenic cell Skou, J.P. (1991). Ét enkelt tidspunkt for star suspensions of barley (Hordeum vulgar c L.). ten på gyldig navngivning inden for botanik Analysis of extracellular proteins secreted by ken. Mcdd. Plantepatologisk Nomenklatur cells in culture. Ph.D. Thesis. (Plant Biology udvalg no. 13. 1-3. Section. Riso National Laboratory. Roskilde. Skou, J.P. (1991). Det videnskabelige navn for Institute for Molecular Biology and Plant græssernes og kornarternes meldugsvamp. Physiology. Aarhus University, Aarhus). Mcdd. Plantepatologisk Nomenklaturudvalg 86 p. no. 13, 3-4. Nielsen, O.J. (1991). Atmosfærisk nedbrydning Skou, J.P., Haahr, V. (1991). Afsvampning og af alternativer til CFCcr. Dansk Kemi 72. resistens mod stribesyge i bvg. Agrologisk, 306-309. no. 1. 23-25. Sielsen, T., Lohse, C. (1991). Stigende mængde Skytte Jensen, B., Jensen, H. (1991). JENSEN, ozon bekymrer forskere. Risonyt. no. 3. 2-4. A program for the computation of chemical Nilsson, K., Skytte Jensen, B. (1991). The ex equilibria in aqueous systems. Version 2.0. perimental validation of geochemical compu Final report for contract FI1W-0079. Geo ter models. Part of final report for contract chemical modelling. (Riso National Labora F11W0080-DK. Gcochcmical databases. tory. Chemistry Section, Environmental (Riso National Laboratory. Roskilde). 35 p. Science and Technology Department, Ros kilde). 117 p. 62 Risø-R-624(EN) Vinther Kristensen, L, Larsen. £.. Solgaard. P. "Electron Transfer" Sateliitc Symposium of (1991). Multielement analyse ved plasma- VIII International Congress of Quantum quadrupol instrument. Dansk Kemi 72, 402- Chemistry. Sophia Antipolis. France. June 404. 25-28. 1991. Dahlgaard, H, Radioactive Tracers in the Greenland Sea. International Greenland Sea 9.5 Presentations Project Workshop. Copenhagen, December 3-5, 1991. Aarkrog, A.. Dahlgaard. H., Foulquier, L, Dahlgaard, H., Chen, QJ.. Sielsen, S.P., Kut-laUimedov, Y., Kulebakma, LG., Myt- Chernobyl Caesium in the Greenland Sea. tenaere. C, Sieben, S.P., Poltkarpoi; G.G., XXVH-CSI Pre-Symposium: Measurements On the Variation of Radionuclide Ratios in of Radionuclides after the Chernobyl Acci Chernobyl Debris. IUR Soviet Branch Semi dent. Bergen. Norway, June 6-8, 1991. nar on the Radioecology and Counter- (Invited) measures, KIEV, April 28 - May 3, 1991. Dahlgaard, H., Radioactive tracer in the Aarkrog. A.. Lectures presented at the Work Green-land Sea. Project Grønlandshavet, shop on Environmental Impact Assessment in Internatmode. Rungstedgård. March 12-13, NPP Siting. Djakarta. Indonesia, September 1991. 23 - October 4, 1991. Dahlgaard. H.. CM. Doc. 1991/C:26 (mimeo) Aarkrog. A., Dahlgaard, H.. Frissel. M.. Foul Contribution to the 79th ICES Staaory quier, L, Karavajeia, E.S.. Kulebakina, Meeting. La Rochelle. France. September 26 LG., Kuhkov, S.V., Molclmnoxa. I.V.. Myt- - October 4, 1991. ICES Paper. tenaere, C. Sielsen, S.P., Polikarpov. G.G., Doll. H.. Erfaringer fra det danske bioteknolo Yushkov. P.I., Environmental Radioactivity in giprogram. NJFs rådgivende gruppe for bio the southern Urals Results of an IUR Expe teknik. Vil vorde Kursuscenter, April 17, dition. IUR Soviet Branch Semminar n the 1991. Radioecology and Countermcasurcs. KIEV. Ellermann. T.. Atmospheric CC13 degradation. April 28 - May 3, 1991. Roskilde University Center, May 21, 1991, Aarkrog, A., Radioccological Problems of Nor Ph.D. lecture. dic Regions. Conference on the radiological Ellermann. T., Sielsen. O. J.. The reactions of and radiation protection problems in Nordic CCI- with NO and NO-,. At the CEO regions, Tromso, Norway, November 21-22, EUROTRAC Atmospheric Chemistry Dis 1991. (Invited) cussion Meeting. York. September 23-25. Aarkrog. A.. The Concept of Seasonality in the 1991. Light of the Chernobyl Accident. XX VII- Giese, H.. Association between RFLP markers CSI Prc-Symposium: Measurements of Ra and QTLs for grain yield in baTlcy. Eucarpia dionuclides after the Chernobyl Accident. mode. Barcelona, Spain, May 29, 1991. Bergen, Norway, June 6-8, 1991. (Invited) Giese, //., RFLP analyser af byg. Sveriges Borbye, L, Pulse field elcktroforese af byg- Landbrugsuniversitet. Svalov, April 29,1991. meldugkromosomcr. Forskningscenter Riso, Giese; //., Molekylærbiologiske studier af Bcllahoj, April 9, 1991. bygmeldugsvampcn. Nordisk mode, Slagteri Borbye, L, Anvendelse af Pulse-Field Gel skolen Roskilde, April 15, 1991. Elec-troforese (PFGE) og Yeast Artificial Giese. H., Genteknologiens indtræden i vækst- Chromosomes (YACs) i genommapping af forædling. NJF kongress, Uppsala, June 19, Erysiphe graminis f.sp. hordei. Den Kgl. 199i. Veterinær- og Landbohøjskole. February 28, Giese, H., The use of RFLP markers in barley 1991. breeding. Barley Genetics Symposium, July Brobrowski, K., Wierzchowski, K.L., Holcman, 24, 1991. J., Ciurak, M., Intramolecular electron trans Giese, H., Molecular studies of the barley fer in oligoprolinc peptides containing powdery mildew fungus. Kollokvium. ETH tryptophan, tyrosine and methionine. At Zentrum. Zurich, November 28, 1991. Riso-R-624(EN) 63 Giese. H.. RFLP teknik. Forelæsning på Den ret af Tillqvist Danmark, Gentofte. March Kgl. Veterinær- og LandbohoJNkoIe. Octo 19. 1991. ber 1, 1991. Jensen. E.5.. Influence of mixed cropping with Giese. K. Tilgængelige DNA-markorer til cereals on biological N\ fixation in grain genomkortlægning. Arboretet, January IS. legumes as evaluated by N isotope dilu 1991. tion. Anambra State University of Technolo Gissel-Sielsen. G-, Et bæredygtigt landbrug. gy. Enwgw. Nigeria, April 25, 1991. Slagelse, November 16, 1991. Jensen, £.5.. Biologisk kvælstofbinding i jord Gissel-Sielsen, G, Presentation of the conclu brugets planteproduktion. NJF 19. Kongres, sion of the jurypanel at "Konsensuskonferen Uppsala, Sverige. June 17-20, 1991. cen om vandmiljøet", February 4. 1991. Jensen, ES., ANCA/MS-kobling af elemen- Gissel-Sielsen, G.. Selenium in crop produc taranalyseudstyr og massespektrometri for tion. Plenary speech at the International bestemmelse af N-isotopforhold. Dansk Sel Symposium on Selenium. Belgrade. May 13. skab for Massespektroskopi, Kobenhavn. 1991. November 26, 1991. Gissel-Sielsen. C. Nitrogen turn-over and Jensen. ES.. The coupling of elemental analy environmental problems. Seminar for the sis and stable isotope ratio mass spectrome Committee for sustainable agriculture. Folke try a powerful tool in 1?N studies of plant- tinget. August 21. 1991. microbe-soil relationships. COST 810 work Nickel. B.. Sehested. K.. Hydrogen abstraction shop in Roskilde on: The use of I?N metho by OH and O- radicals: isotope effect. Miller dology in studies on the role of VA-mycor- Con-fcrcncc. Giens. France. September 16- rhizas in N-cycling. December 5-6. 1991. 20, 1991. Jia-Jun Ke, Sørensen. £., Fixation of Heavy Holcman J.. Løgager, T.. Sehested K.. Kloning Metals in Gay and Sludge under Elevated U.. Reactions of pcroxodisulfatc and SO J Temperatures and Pressures ICCM-91. radical with other radicals in aqueous solu Bombay. India. 1991. (Invited) tion. At the CEC/EUROTRAC Atmospheric Johansen, .4., Jakobsen. I., Jensen, E.S., Ni Chemistry Dis-cussion Meeting in York. trogen transport and depletion of soil nitro September 23-25. 1991. gen by external hyphae of VA-myconhizae. Haahr, V.. Dyrkning af ærter. 12. nordiske for 3rd European Symp. on Mycorrhizae, Uni skerkursus i plantekultur. Tune Landbrugs versity of Sheffield, Sheffield. UK, August skole. March 6. 1991. 19-23, 1991. Ikram. .4., Jensen, E.S.. Jakobsen, /.. Possible Joner. EJ., Jakobsen. /., Enhanced growth of direct transfer of 1?N and "P from Pueraria external VA-mycorhizae hyphae in soil plwseoloides to Hevea brastltensis via my- amended with straw. 3rd European Symp. on corrhizal links. COST 810 Workshop: The Mycorrhizae, University of Sheffield, Shef Use of ,:,N Methodology in Studies on the field. UK, August 19-23, 1991. Role of VA Mycorrhizas in N Cycling. Ros Jørgensen, J. Helms, Mlo aggressiveness in kilde. December 5-6. 1991. barley powdery mildew. Statens Planteværn. Jakobsen, I., Phosphorus transport by external Ås, Norge (Nord. Rcsistensbiol. Symp.), hyphae of arbuscular mycorrhizas. 3rd Euro February 11-14, 1991. pean Symp. on Mycorrhizac. University of Jørgensen, J. Helms, The barley powdery Sheffield, Sheffield, UK. August 19-23. mildew interaction: Genetics and gene func 1991. tion. Max Planck Institut fur Zuchtungsfor- Jensen, E.S., Bælgplanter og kvælstofbinding i schung. Koln-Vogelsang. Germany, April det okologiske jordbrug. Alternativt Jordbrug. 24. 1991. Den Kgl. Veterinær- og Landbohøjskole. Jørgensen, J. Helms, Resistcnsforædling. Tre March 4. 1991. forelæsninger pS Den Kgl. Veterinær- og Jensen, ES, Anvendelse af elementår analyse i Landbohøjskole. November 12. 15, and 18, undersøgelser over kvælstofomsætning i dyr 1991. ket jord. Elementår-analyse seminar arrangc- 64 Riso-R-624(EN) Jørgensen. R.B., Transformation af enkimbla Miller. A. A High Dose Reference Laboratory. dede planter. Slagteriskolen. Roskilde. No Int. Conf. on Radioisotopes and Radiation vember 20. 1991. Applied to Industry. Berlin. Germany, Sep Linde-Laursen, /., Relationships in the Genus tember 16-19. 1991. Hordeum: Giemsa C-banded karyotypes. 1st Motter, S-. Tids-opioste optiske undersogeber Int. Triticeae Symp.. Helsingborg. Sweden. af biologiske problemstillinger. Roskilde August 1, 1991. University Center, Februaiy 15. 1991, Ph.D. Logager, T., Holcman, J., Sehested K, The lecture. ferryl ion. A study of oxidation of ferrous ion Sielsen, S P. A Compartmental Model for the by ozone in acidic solutions. CEC/ Coastal Waters of the North-East Atlantic EUROTRAC Atmos-pheric Chemistry Dis Including the Baltic Sea. MAST Modelling cussion Meeting. York. September 23-25, Workshop. Luxembourg. September 9-13. 1991. 1991. Løgager, T.. Holcman /.. Sehested K-, The Sielsen, S.P..A Compartmental Model for the ferryl ion in acidic solutions. Miller Confer Coastal Waters of the North-East Atlantic ence, Giens. France. September 16-20. 1991. including the Baltic Sea. Sixth MORS Logager, T.. Holcman J.. Sefiested K. The meeting. Stockholm. June 10-14.1991. fenyl ion. A study of oxidation of ferrous ion Sielsen. T., Forekomst og kilder til PAH i by ozone in acidic solutions. Annual meeting atmos-fzren. Sektionen for Organisk Kemi. of (he Danish Centre for Atmospheric Re Kemisk Forenings Arsmode, Odense Univer search (DCAR). Copenhagen. November 4. sity. June 12. 1991. 1991. Sielsen, S.P.. Radioecological studies in Den Marker i, F., Sielsen. O.J.. The reactions of OH mark, the Faroe Islands and Greenland. radicals with a series of n-ch!oroaIkanes. At Meeting on Euratom Treaty Article 35 and the CECEUROTRAC Atmospheric Chemi 36. Luxembourg. June 20.1991. stry Discussion Meeting. York. September Sielsen, OJ., Peroxy radicals - Spectra, kine 23-25, 1991. tics and mechanisms. At Nordic Symposium Miller, A., Bestråling af polymere materialer. on Atmospheric Chemistry. Stockholm and Materialeforskning pi Risø. Niels Bohr Au Tallinn. December 17-19. 1991. ditorium. Riso. March 6. 1991. Sielsen. J., Pilegaard H. Andersen. H.-V., Miller, A.. 1) Sterilization of medical products Egelov. A.H.. Hilbert. G. Jensen, F.P.. using electron accelerators: Facility characte Lohse, C. Comparison of differential optical rization and product validation. 2) Dosimetry absortion spectroscopy (DOAS) measure and process control: Routine monitoring, sta ments of 03. NO-, and SO-, with those by tistical limitations and dosimetry systems. 3) conventional methods. At the TOR work Aspcc:s of electron beam processing: Cost, shop. Paris. October 30-31. 1991. induced radioactivity, shielding and safety. Sielsen, T.. Pilegaard K, Andersen, H.-V.. UNDP/IAEA/RCA Regional Training Course Egelov. A.H., Htlbert, G. Jensen. F.P., on Electron Beam Irradiation Technology, Lolise, C Evidence for a new type of at Shanghai. China. August 26 - September 6. mospheric nitrogen compounds and compa 1991. rison of different air pollution methods. Miller, A., Achieving Traceability. Indlntcma- Annual meeting of the Danish Centre for tio-nal Workshop on Dosimetry for Radia Atmospheric Research (DCAR) Copenhagen. tion Processing. ASTM. Washington. D.C.. November 4, 1991. USA, October 7-11, 1991. Sielsen, T., Pilegaard, K, Bang Jensen, A., Miller, A., Dosimetry at a 400 kcV accelerator Sources of Polycyclic aromatic hydrocarbons International Atomic Energy Agency Re at an international airport. 13th International search Coordination Meeting on Radiation Symposium on Polynuclear Aromatic Hy Processing of Flue Gases, Warsaw. Jachran- drocarbons, p. OC55, Palais Des Congrés, ka, Poland, May 27-31, 1991. (Invited) Bordeaux Lac, France, October 1-4, 1991. Ris«i-R-624(EN) 65 Stelsen. T.. Occurrence and sources of PAH in Pedtrsen. L.H.. Characterization and partial the atmosphere. Ai the Danish Chemical purification of 1.3-B-glucan synthase from Society Annual Meeting. Odense. June 12. barley leaves. Biokemisk Forenings Årsmø de, pjglsoctnrjct. October 24-26, 1991. Sceben. OJ.. Reactions of OH radicals with Pedersen. LH.. Callose synthesis in barley CFCs. STEP-HALOCSIDEAFEAS work leaves. Statens Plantcvacmscenter, Biotekno shop. Dublin. May 14-16. 1991. logigruppen. Lyngby, November 8. 1991. Sieben. T.. Pilegaard A'., Forekomst af og Petersen. L. Anvendelse af RFLP i resistens- kilder til luftforurening med PAH ved Ko forardlingec. Den Kgl. Veterinær- og Land benhavns Lufthavn. 4th Nordic Symposium bohøjskole. February 28, 1991. on Organic Pollutants, p. 40, Sonip Herre Rasmussen. S.K.. Peroxidase gene expression gård. Denmark. September 8-11. 1991. in seed and leaves of barley. Symposium on Sieben. OJ.. Atmospheric Chemistry in Den "Enzymes in Plant Pathogen Resistance", mark. At Nordic Symposium on Atmospheric Danish Biochemical Society. Copenhagen. Chemistry. Stockholm and Tallinn. December March 12.1991. 17-19. 1991. Rasmussen. S.K., Goning and characterization Sirtsen. OJ-. Sehested. J.. Atmospheric che of peroxidase genes from barley. Meeting on mistry of HCFCs and HFCs studied at Riso. Barley-Pathogen interaction organized by Annual meeting of the Danish Centre for David Collinge for the Nordic Research Atmospheric Research (DCAR). Copenhagen. Council. April 15. 1991. November 4.1991. Rasmussen. S.K.. Molecular cloning, nucleo Sieben. OJ.. Spectra and Kinetics of Selected tide, amino acid and carbohydrate sequence Halogenated Alkyl and Halogenated Alky] of barley peroxidases: Developmental and Peroxy Radicals. At the CECEUROTRAC tissue-specific expression. Instituto Biosin- Atmospheric Chemistry Discussion Meeting. tcsi Vcgetali. CNR Milano. Italy. December York. September 23-25. 1991. 19. 1991. Sieben. O J.. Atmospheric chcmi^ry of CFC Rasmussen. S.K, JcJiansson. A.. Theilade, B., alternatives studied at Riso. At the first Nor Organization and expression of genes coding dic interdisciplinary research conference on for barley seed peroxidases. Tucson. Arizo the greenhouse effect. Copenhagen. Septem na. USA. October 6-11. 1991. ber 16-18. 1991. Roed J.. Effectiveness of a Skim and Burial Sieben. OJ.. Atmospheric Chemistry and Riso Plough. Workshop on the Relative Effective National Laboratory - Gas Phase ineiic ness of Agricultural Countermcasures Tech Studies at the Section for Chemical Reactivi niques. "REACT. Brusscl, October 1-4, ty. At the Institute for Physical Chemistry. 1991. The University of Kiel. June 1991. Roed J. Ploughing as an effective counter- Sieben. O J.. Sidehounm, H.W.. Donlnn. M.. measure. Erosoil - research meeting. Cada- Treacy. J.. Reactions of OH radicals with rache. France. June 26. 1991. alkyl nitrates and nitroalkancs. Annual Roed J.. Deposition and resuspension of ra meeting of the Danish Centre for Atmosphe dioactive material in Pripjct. Dorstroj tekni ric Research (DCAR). Copenhagen. Novem ka. Minsk. July 15. 1991. ber 4. 1991. Roed J. 1. Deposition on and run-off from Pedersen, L.H., Characterization and partial radioactive material from surfaces. 2. Strate purification of 1.3-B-glucan synthase from gics on decontamination. Workshop on Re barley leaves. Annual Meeting of The Ame clamation of Radioactive contaminated area, rican Society of Plant Physiology. Raslaborg. Sweden, April 22-24, 1991. Albuquerque. New Mexico. USA. July 28 - August 1. 1991. 66 Ris«»-R-624(EN) Roed, J., Andersson, KG, Development of Countermeasures *rom observations on con taminated soils. XXVII-CSI Pre-Sympo- sium: Measurements of Radionuclides after the Chernobyl Accident. Bergen, Norway, June 6-8, 1991. (Invited) Rosendahl, L., Exchange of metabolites across the peribacteroid membrane in pea root no dules. Umeå, Sverige, October 2, 1991. Rosendahl, L., Involvement of the peribacteroid space of pea nodules in exchange of com pounds between the symbionts. Int. Symbio sis Congres, Jerusalem, Israel, November 19, 1991. Rosenkrands, /., Rasmussen, S.K., Svendsen, I., Hejgaard, J., Serpins of barley grains with potential inhibitory activity. Biokemisk For enings årsmode, Fuglsocentrct, October 24- 26, 1991. Sehested K, Ozone-watcr-phase chemistry in relation to the troposphere. Department Se minar, Riso, December 4, 1991 (in Danish). Sehested, J., Nielsen, O.J., Atmospheric che mistry of HCFCs and HFCs studied at Riso. At the CEC/EUROTRAC Atmospheric Che- mi? •' Discussii Meeting, York, September 23-25, 1991. Tlieilade, B., Rasmussen, S.K., Karakterisering og mapping af bygperoxidase BP 2A-genet. Biokemisk Forenings årsmode, Fuglsocentrct, October 24-26, 1991. Wilbrandt, R., The po,ori'»al energy surface cf the Tj state of 1,3,5-hexatrienes. invited lecture at the XVth Internationa) Conference on Photochemistry, Paris, July 28 - August 2, 1991. Wilbrandt, R., Triplet states of polyenes. Invited lecture at the International Meeting on Time-resolved Vibrational Spectroscopy of Biological and Related Molecules, Nara, Japan,June 8,1991. Wilbrandt, R., The poiv.itial energy surface cf the Tj state of 1,3,5-hexatrienes and me thylated derivatives: A survey of present knowledge. Invited lecture at the Fifth Inter national Conference on Vibrational Spectro scopy, Tokyo, Japan, June 2-7, 1991. Risø-R-624(EN) 10 Publications in press Anastasi, C, Broomfield, M., Nielsen, O.J., Jakobsen. I.. Phosphorous transport by external Pagsberg, P.. "The reactions of CH,SH radi hyphae of vesicular-arbuscular mycorrhizal. cals with O-,, NO and NO,". - J. Chem. - In: Mycorrhizal in Ecosystems (eds I.J. Phys. Alexander, J.H. Fitter, D.H. Lewis and D.J. Andersen, L, Jørger^en, J. Helms, Mlo ag READ); CAB International. gressiveness of barley powdery mildew. - Jensen, E. S., The release and fate of nitrogen Norwegian Journal of Agricultural Sciences. catch crop material decomposing under field Bertelsen, F., Jensen, E.S., Gaseous nitrogen conditions. - Journ. of Soil Sci. 43. losses from field plots grown with pea Jensen, HP., Christensen, E., Jørgensen, J. (Pisum sativum) or spring barley (Hordeum Helms, Powdery mildew resistance genes in vulgare) estimated by 1_ N mass balar.ee and 127 Northwest European spring barley va acetylene inhibition technique. - Plant and rieties. - Plant Breeding. Soil. Jensen, J., Co-ordinator's report: Chromosome Boctius, I., Boetii'S, J.. Hansen, H.J.M., Studies 5. - Barley Genetics Newsletter 20. on lipid synthesis by incorporation of C- Johansson, A.. Rasmussen, S.K., Harthill, J., acetateduring experimental maturation of Welinder, K.G., cDNA, amino and carbohy silver eels, Anguilla anguilla. - Dana 9. drate sequence of barley seed peroxidase Borbye, L, Linde-Laursen, I., Christiansen. BF 1.- Plant Mol. Biol. S.K., Giese, H., The chromosome comple Jørgensen. J. Helms, Summary of poster ses ment or Erysiphe graminis f.sp. hordei ana sion X: Disease Resistance and Pest Mana lysed by light microscopy and field inversion gement. - Barley Genetics VI vol. 2. gtl electrophoresis. - Mycological Research. Jørgensen. J. Helms., Multigene families of Brodersen, K., Nilsson, K., Pores and Cracks in powdery mildew resistance genes in iocus Cemented Waste and Concrete. - Cement Mia on barley chromosome 5. - Plant and Concrete Research. Breeding. Dahlgaard, H, Bodskifte, S., "SENSI": A Jørgensen. J. Helms. Co-ordinator's report: Model describing the Accumulation and Disease and pest resistance genes. - Barley Time-Integration of Radioactive Discharges Genetics Newsletter 20. in the Bioindieator Fucus vesiculosus. - J. Jørgensen, J. Helms. Previous achivements (in Environ. Radioactivity 15. the ECP/GR barley programme 1980-1991). Giese, H., The use of RFLP markers in barley - In: International Crop Network Series. breeding. - In: Barley Genetics VI. Helsing Report of an International Barley Working borg. Sweden. Session. Giese, H., Replication of DNA during barley Jørgensen, J. Helms, Discovery, characteriza endosperm development. - Canadian Juurnal tion and exploitation of Mlo powdery mil of Botany. dew resistance in barley. - In: R. Johnson Jakobsen, I., Abbott, L.K., Robson. AD., Ex and G.J. Jellis (eds), Breeding for Disease ternal hyphae of vcsicular-arbuscular mycor- Resistance, Kluwer Acad. Publ., Dordrecht. rhizal fungi associated with Trifolium subter- BSPP Symp., Newcastle, England, December raneum. 1: Spread of hyphae and phospho 18, 1991. rous inflow into roots. - New Phytologist Jørgensen, J. Helms, Sources and genetics of 120. resistance to fungal pathogens. - In: Barley: Jakobsen, I., Abbott, L.K., Robson, A.D., Ex Genetics, Molecular Biology and Biotechno ternal hyphae of vesicular-arbuscular mycor- logy, Shewry, P. (ed.). CAB International, rhizal fungi associated with Trifolium subter- UK. raneum. 2: Hyphal transport of ""P over Jørgensen, R.B., Andersen, B., Andersen, J.M., defined distances. - New Phytologist 120. Effects and characterization of the condition ing medium that increase colony formation 68 Risø-R-624(EN) from barley (Hordeum vulgare L.) proto Rosendahl. L.. Dilworth. M.J.. Glenn, A.R., plasts. - J. Plant Physiol. Exchange of metabolites across the peribac- Linde-Laursen, I., Giemsa C-banded karyoty teroid membrane in pea root nodules. - J. pes of cultivated and wild barley 'Hordeum Plant Physiol. vulgare s.l.) - Barley Genetics Newsletter 20. Skou, J.P., Identifikation og bevaring af arve Linde-Laursen, I., Barley x rye hybrids elimi- lige egenskaber. - Våxtskyddsnotiser. na-ting accessory chromosomes of rye. - Skou, J.P., A series of xerophilic Chrysospo- Hereditas. rium species. - Mycotaxon 43: 237-259. Linde-Laursen, J., Bothmer, R. von, Jacobsen, Sommer, S.G., Jensen, E.S., Schjørring, J.K., N., Relationships in the genus Hordeum: Leaf absorption of gaseous ammonu' after Giemsa C-bandcd karyotypes. - Hereditas. application of pig sherry on sand between Lorenzeuo, P., Bjergbakke, £., Hickel, B., rows of winter wheat. - In: Proceedings of "Water Tadiolysis under NET conditions". COST/Biosphere Atmosphere, Exchange. 1SFNT 2, Karlsruhe. Proceedings. Joint Workshop, October 28-30, 1991, Delft. Luhrs, R., Nielsen, K-, Microspore cultures as Sørensen, £., Bjerre, A.B., Combined Wet donor tissue for the initiation of embryogenic Oxidation and Alkaline Hydrolysis of cell suspensions in barley (Hordeum vulgare Polyvinylchloride. - Waste Management. L.). - Plant Cell, Tissue and Organ Culture. Sørensen, £., Bjerre, A.B., On the stabilisation Markert, F.. Nielsen, O.J., "Rate constants for of Niobium(V) solutions by Zirconium(IV) the reaction of OH radicals with 1-ChloroaI- and Hafnium(IV). - Talanta. kanes at 295 K". - Chem. Phys. Lett. Wallington, T.J., Nielsen, C J., Novel method Nielsen, T., Pilegaard, K., Jensen, A.B.. Occur for the measurement of gas phase psroxy rence and sources of atmospheric polycyclic radical absorption spectra. - J. Phys. Chem. aromatic hydrocarbons at an international Uallington. T.J., Ball, J.C., Nielsen, O.J., airport. - Polvcyclic Aromatic Compounds. Bart-kiewicz, £., Spectroscopic, kinetic and Nielsen, O.J., Ellermann, T., Barikiewicz, £., mechanistic study of CHiFO-> radicals in the Wallington, T.J., Hurley, M.D.. "UV absorp gas phase at 298K. - J. PhysT Chem. tion spectra and mech.— isms of the self reac tion of CHF-,OT radicals in the gas phase at 298 K". - Chem. Phys. Lett. Nielsen, K. A., Hansen, J.B.. Appearance of extracellular proteins associated with somatic embryogenesis in suspension cultures of barley (Hordeum vulgare L.). - J. Plant Phy siol. Pilegaard, K., Jensen, E.S., Foliar uptake of NOT in bailey. Proceedings of the COST/ BIATEX Workshop, Delft, Holland, October 1991. - CEC Air Pollution Research Report. Pilegaard, K., Atmospheric Heavy Metal De position in Northern Europe 1990. Rasmussen, V., Giese, H., M.kkelsen, J.D., Induction and purification of chitinase in Brassica napus L. ssp. oleifera infected with Phoma Ungarn. - Planta. Rasmussen, S. K., Johansson, A., Nucleotide sequence of a cDNA coding for the barley seed protein CMa: an inhibitor of insect a- amylase. - Plant MoleculaT Biology. Risø-R-624(EN) 69 11 Education 11.1 Ph.D. Theses 11.3 Contribution to Scientific Cources Andersson, K.G., 1991. Contaminalion and decontamination of urban areas. - Ph.D. Aarkrog, A., Dahlgaard, H., Hansen H.J.M., Thesis, 94 p. Technical University of Den Nielsen, S. P., Nordic postgraduate course on mark. Radioecology, Lund University, April 1991 Bertelsen, F, 1991. Denitrifikation og bælg (NKS/RAD). Four lectures: Source Terms plantedyrkning (Denitrification and the culti and Inventories of Antropogenic Radionu vation of legumes). - Ph.D. Thesis, 72 p. clides, Statistical Treatment of Data, Marine Ellermann, T., 1991. "Atmospheric CC13 De Radioecology, Compartmental Modelling in gradation", Ph.D. Thesis, Roskilde University Radioecology. Center. Aarkrog, A., Lectures presented at the Work Nielsen, KA., 1991. Establishment and bioche shop on Environmental Impact Assessment mical characterization of embryogenic cell in NPP Siting. Djakarta, Indonesia, Septem suspensions of barley (Hordeum vulgare L.) ber 23 - October 4,1991. - Ph.D. Thesis, Riso National Laboratory and Aarhus University, 86 p. Moller, S., 1991. Sensitized triplet E/Z Photo- isomerization of 1,3.5-hexatriene and 2.5- dimethyl-l,3.5-hexatriene. - Ph.D. Thesis, Roskilde University Center. 11.2 M.Sc. Theses Jacobsen, F., Kjærsgaard, U.. Hansen, T. M., 1991. Ozonolysis of ascorbic acid, (in Da nish) Roskilde University Center, Roskilde. Johansson, A., 1991. Kloning og sekventering af en frospecifik bygperoxidase BP 1. (in Dan^h) University of Copenhagen, 75 p. Justesen, AF., 1991. Restriction Fragment Length Polymorphism og Random Amplified Polymorphic DNA som markorer til kortlæg- ningsbaseret kloning i Erysiphe graminis f.sp. hordei. Royal Veterinary and Agricultural University, Copenhagen, 88 p. Rcsmussen, H. Nørgaard, 1991. Oprensning og sekventering af peroxidase cDNA-kloner fra bygblade (in Danish). Technical University of Denmark, 104 p. 70 Risø-R-624(EN) 12 Exchange of Scientists Ahmed, Dr. S., ECC Fellowship, NCD McLaughlin, Dr. W.L.. National Institute of Pinstech, Nilore. Islambad, Pakistan (1 year). Standards and Technology, Gaithersburg Anastasi, Dr. C, University of York, England MD, USA (2 weeks). (1 week). Marihe, F., Institut fiir Genetik und Kultur- Bajdor, Dr. K., Industrial Chemistry Research pflanzenforschung, Gatersleben, Germany (2 Institute, Poland (3 months). weeks). Bartkienicz, M.Sc. £., Agricultural and Mordzinski, Dr. A., Polish Academy of Teachers University, Siedlce, Poland (6 Sciences, Poland (2 weeks). months). Nat/t, Dr. B. Nagender, National Institute of Brobrowsid, Dr. K., Polish Academy of Oceanography, India Sciences, Poland (4 weeks). Orlandi, Prof. G., University of Bologna, Italy Burlinska, Dr. G, Institute of Nuclear Che (1 week). mistry and Technology, Warszawa, Poland (2 Pearson, Dr. J.N., School of Agriculture, The weeks). University of Western Australia, Perth Burns, Dr. D., National Physical Laboratory. (4 months). Teddington, UK (1 week). Pikaev, Prof. A.K., Institute of Physical Byrne, M., Imperial College, London. England Chemistry, Academy of Science, Moscow, (4 weeks). Russia (2 weeks). Christensen, Prof. //., Studsvik Energiteknik Ratajczak, Dr. £., University of Wroclaw, AB, Sweden (4 weeks). Poland (1 month). Christiansen, S. K.. visiting scientist at Depart Sharpe, Dr. P., National Physical Laboratory, ment of Plant Pathology. Cornell University. Teddington, UK (1 week). Ithaca, New York 14850, USA (1 year). Sidebottom, Dr. K, Univerisity College Chung, Dr. W.H.. Pusan National University. Dublin, Ireland (2 weeks). Korea (2 weeks). Simpson, Dr. V.J.. University of York, Eng Dahlan, Dr. K.Z. Hj. AT. Nuclear Energy Unit, land (1 week). Kajang. Malaysia (2 weeks). Solar, Prof. S., University of Vienna, Austria Getoff, Prof. .V., University of Vienna, Austria (1 month). (1 month). Szaloki, Dr. I.. Debrecen. Hungary. Han, Dr. E.J., Port Angeles, USA (4 weeks). Ten Wolde, A., University of Leiden, The Hickel, Dr. B., CNRS, Saclay, France (2 Nether-lands (1 month). weeks). Tliiele, V.. Institut fiir Pflanzenziichtung. Giil- Ikram. Dr. A., Microbiol. Division. The Rubber zow, Germany (2 weeks). Research Institute of Malaysia (RR1M) (6 Wallington, Dr. T., Ford Motor Co., Dearborn, months). USA (2 weeks). Jochimsen, lektor, B.U., Aarhus University. Denmark (1 year). Joner, Stud.dr.sciem., £., Agricultural Univer sity of Norway (4 months). Jowko, Dr. A., Agricultural and Teachers Uni- ver-sity, Siedlcc, Poland (1 week). Kloning, Dr. U, Århus University, Denmark (4 weeks). Korotkov, A., Institute of Biology of the Southern Seas, SSR. Sevastopol, USSR (2 months). Risø-R-624(EN) 71 13 Cooperative Projects Radioactive tracers in the Greenland Sea. Part EUROTRAC-BIATEX. Biosphere/Atmosphere of the international Greenland Sea Project. H. Exchange of Pollutants. K. Pilegaard. Dahlgaard. EC-project on Deposition in Urban Areas. Studies on the Transport of Coastal Water from Collaborators: UKAEA, Harwell, GSF, Munich. the English Channel to the Baltic Sea using J. Roed. Radioactive Tracers. Marine Science and Tech nology Programme (MAST), CEC. Cooperative EC-Sovjet Project on Countermeasures. projekt including Riso National Laboratory; CHECIR, Ukraine. J. Roed. Federal Maritime and Hydrographic Agency, Germany (Formerly DHI): Netherlands Energy EC-project on Urban Decontamination. Colla Research Foundation: Commissariat a l'Energie borators: UKAEA, Harwell, Catholic Univer Atomic, France: Ministry of Agriculture, Fi sity, Leuven, Glasgow University. J. Roed. sheries and Food. Lowestoft. UK. Project coordinator. 1990-1993. H. Dahlgaard. S.P. EC-project on Indoor Deposition. Collabora Nielsen. tor: Imperial College, London. J. Roed. Nordic Radioecology Cooperation (NKSRAD). F' -project on Weathering and Resuspension. RAD1 - Education, Quality Assurance. Me Collaborators: UKAEA. Colchester, GSF, Mu thodology; RAD2 - Aquatic Radioecology; nich. J. Roed. RAD3 - Agricultural Ecosystems; RAD4 - Natural Ecosystems. A. Aarkrog. H. Dahlgaard, EC-project on Development of Skim and S.P. Nielsen. Burial Plough. Part of RESSAC; Main Colla borator: Cadarache, France. J. Roed. Radioccology of scminatural ecosystems (CEC). Cooperative project including Riso NKA-project on Waste Created by Clean Up National Laboratory, (DK), Nuclear Energy of an Urban Area. Collaborators: Helsinki Board (IR) (Coordination). Institute of Ter University, Agricultural University, Oslo, SSI, restrial Ecology, Merlcwood (UK), Swedish Sweden. J. Roed. University of Agricultural Science, Uppsala (S), University of Thessaloniki (G). A. Aar IAEA Project on Validation of Model Parame krog, S.P. Sidsen. ters VAMP. J. Roed. Riso's integrated environmental project (RIMI). Cesium sulphate processes from pollucit. K. O.J. Nielsen, T. Nielsen, K. Pilegaard, P. Sol- Nilsson. gaard. EFP-projcct on temperature-time variations in Uptake of Nitrogen compounds by above North Central Trough sediments by fission ground plant parts. Collaborator: National En track analyses of selected drill cores. Collabo vironmental Research Institute DK. K. Pile rators: University of Copenhagen and DMU. H. gaard. Kunzendorf. Biological monitoring of heavy metals. Colla SNF-project on Cretaceous-Tertiary boundary borator: Laboratory of Environmental Research studies by Copenhagen University. H. Kunzen Institute. Science and Education. The Technical dorf. University, Lyngby. K. Pilegaard. 72 Risø-R-624(EN) Trace element studies in sediments from the Geochemical Modelling. The JENSEN geoche Skagerak-Kattegat area. Collaborators: Geolo mical computer program. A joint CEC project gical Survey of Denmark and University of within the MIRAGE group. B. Skytte Jensen. Gothenborg. Sweden. H. Kunzendorf, P. Sol- gaard. LITTLE JOE. An expert system to support geochemical modelling. A joint CEC project Baltic Marine Cooperation. Marine environ within the MIRAGE group. B. Skyue Jensen. mental studies in the Baltic Sea. Collaborators: Roskilde University Center and Danish Road Colloid Behaviour. A joint CEC project within Laboratory. H. Kunzendorf. the MIRAGE group. B. Skytte Jensen. Geochemistry studies of marine ferromanga- Uncertainties in the Modelling of Migration nese phases. Collaborators: University of Kiel, Phenomena. A joint CEC project within the New Zealand Oceanographic Institute and Na MIRAGE group. B. Skytte Jensen. tional Institute of Oceanography, India. H. Kunzendorf. MODECS. Molecular Design of Chemical Sy stem. An R&D-forum for industries and ins'i- Development and application of instrumental tutions interested in the mentioned topic. B. analytical techniques for application in geoche Skytte Jensen. mistry. Collaborator: Tracechem, Copenhagen. H. Kunzendorf. EC-project on Atmospheric chemistry of halo- genated compounds. 9 European laboratories. EUROTRAC-TOR. Troposphcric ozone re O.J. Nielsen. search. Danish collaborator: National Environ mental Research Institute. T. .\iclsen. EC-Project on Atmospheric Chemistry of Organic Sulfur and Nitrogen Containing Com Riso's integrated environmental project (RIMI). pounds. O.J. Nielsen. T. Nielsen, P. Solgaard. EUROTRAC-LACTOZ, Laboratory Studies of DCAR-Traffic-PAH project. Collaborators: Chemistry Related to Tropospheric Ozone. O.J. National Environmental Research Institute, Nielsen. Institute of Toxicology, dk-Teknik and Ko benhavns Kommunes Miljokontrol. T. Nielsen, Ford Motor Company collaborative project on P. Solgaard. CFC substitutes, O.J. Nielsen. CEC Community Bureau of Reference Inter- NATO Collaborative Research Grant Denmark. comparison of trace elements in lichen. P. G. Orlandi, Italy. A.M. Drouwer, H.J.C. Jacobs, Solgaard. J. Lugtenburg, The Netherlands. R. Wilbrandt, Denmark. FLAIR Concerted Action No 10. The Measu rement of Micronutrient Absorption and Status. Investigation of MOLSWITCH compounds. P. Solgaard. CISMI. Collaborator: K. Bechgaard, University of Copenhagen. R. Wilbrandt. Treatment of wastes. Collaborators: NKT Research Center and Canadian Occidental. £. Danish Natural Science Research Council, Sørensen, A.B. Bjerre. project on the characterization of potential energy surfaces of molecules and radicals. Geochemical databases. A joint CEC project Collaborators: F.W. Langkilde, Royal Danish within the CHEMVAL group. B. Skyue Jensen. School of Pharmacy, O.S. Mortensen, Odense University. R. Wilbrandt. Risø-R-624(EN) 73 Danish Natural Science Research Council, Askov. Danish Research Service for Plant and project on atmospheric chemistry. Collabora Soil Science. £.5. Jensen. tors: Copenhagen University and National Environmental Research Institute. O.J. Nielsen. Nutritional therapy of patients with livercinho- sis 1990-1992. Collaborator: K. Nielsen. Me Rise's integrated environmental project (RIMI). dical Department A. Rigshospitalet, Copenha O.J. Nielsen, T. Nielsen, P. Solgaard. gen. E.S. Jensen. Euromet. Collaboration with National Physical Exchange of metabolites across the peribacte- Laboratory, UK on calibration and measure roid membrane in legume root nodules 1989— ments of ionizing radiation. A. Miller. 1992. Collaborators: M.J. Dilworth and A.R. Glenn, Murdoch University, Western Australia. IAEA. Research agreement no 6919: Reference L Rosendahl. dosimetry for industrial Electron Accelerators. A. Miller. Compound exchange in symbiotic nitrogen fixation. Collaborator: B.U. Jochimsen, Uni IAEA. Research agreement no 6612: Methods versity of Aarhus. L. Rosendahl. for measurement of absorbed dose and dose distribution at 200-11)00 kcV electron beams. Interaction between different crop plants and A. Miller. weeds. Collaborator: B. Sogaard. The Royal Veterinary and Agricultural University. H. Assessment of air pollutant effects on growth, Doll. quality and metabolism of agricultural crops. Subcontract to NERI EEC collaboration. K.C. Efficiency of partial mildew resistance in bar- Enpild. Icy and correlation with secondary metabolites in the leaves. Collaborator: B. Sogaard, The Mikrobielle processer i rodzonen i relation til Royal Veterinary and Agricultural University. planternes forsyning med næringsstoffer 1988- H. Doll. 1991 (Microbial processes in the root zone in relation to supply of plants with nutrients). Linkage map of the barley genome. Collabora Collaborators: Seven Danish research labora tors: The Royal Veterinary and Agricultural tories. /. Jakobsen, A. Johansen. University; the Danish plant breeding stations: Abed, Sejet. Pajbjcrg; European and American Carbon drain and phosphorus transport by VA- barley geneticists. H. Giese, J. Jensen, L. Pe mycorrhizal fungi. Collaborators: L.K. Abbott tersen, S. Rasmussen. and J.N. Pearson, The University of Western Australia. /. Jakobsen. Molecular genetics of Erysiphe graminis f.sp. hordei, the causal agent of barley powdery Evaluating the role of legume cover crops in mildew. Collaborators: Danish Plant biotechno the nitrogen nutrition of rubber 1989-1993. CE logy Research Center; The Royal Veterinary project under The International Scientific Co and Agricultural University; J. McDermott, operation Programme. Collaborator: The Rub ETH Zentrum, Zurich. H. Giese, M. Lyngkjær, ber Research Institute of Malaysia. Kuala L Borbye, M. Rasmussen. Lumpur. /. Jakobsen, E.S. Jensen. Genetic variation between cotton varieties. Kombineret halmnedmuldning og eftcrafgrode- Collaborator: The Royal Veterinary and Agri dyrkning 1989-1992 (Combined straw incor cultural University. H. Giese, B. Rolling. poration and cultivation of catch crops 1989- 1992). Collaborators: I. Thomsen and B. T. Genetic markers for embryogenesis in barley. Christensen, Government Research Station Collaborators: University of Copenhagen; D. 74 Ris Ny meldugresistens i byg. 1989- (New sources of powdery mildew resistance genes in barley. 1989-). Collaborators: Three Danish cereal breeding companies. J.H. Jørgensen. HP. Jensen. Risk assessment of genetically modified plants. Collaborators: A. Buchtcr-Larsen. Danisco Maribo Division; J. Frcdshavn. The Royal Veterinary and Agricultural University; S. Mark. National Forest and Nature Agency. R.B. Jørgensen. Recombination estimates and physical chemical distances on the chromosomes. Collaborator: The Royal Veterinary and Agricultural Univer sity. /. Linde-Laursen. H. Giese. C. Pedersen. Polyploid Hordeum species. Collaborators: R. von Bothmcr. Department of Crop Genetics and Breeding. The Swedish University of Agricultural Sciences. Svalov. Sweden. /. Lin de-Laursen. Caliose synthesis in barley. Collaborators: J. Hejgard and S. Jacobsen. Danish Technical University. S.K. Rasmussen. L.H. Pedersen. Barley peroxidases. Collaborators: Aarhus Uni versity; Danish Plant Biotechnology Program me. S.K. Rasmussen. B. Vxeilade. Risø-R-624(EN) 75 14 Guest Lectures Professor T. Bally. University of Fribourg. .V Pearson. Department of Soil Science. Uni Switzerland: "Vibrational structure of organic versity of Western Australia: "Competition radical cations: A systematical approach". between mycorrhizal fungi". Dr D. Dennis, Edinburgh Instruments. Professor A.K. Pikaev, Institute of Physical Edinburgh. UK: "Fluorescence lifetime spec Chemistry of the USSR Academy of Sciences. troscopy". Moscow. USSR: "Radiation processing and related dosimetry in the USSR". Dr P. Devolder, Laboratoire de Cinctiquc et Chemie de la Combustion. Université de Lille. P. Steen. .Maribo Seeds. Denmark: "Experience France: Troposphcric oxidation of aromatics: with gcnespliced sugar beets in field experi Reactions of a feu- benzyl type radicals with ments". 0: and N0S". U. Sectoring. Institute of Spore Plants. Univer Dr A. Grabonska. Institute of Physical Che sity of Copenhagen: "Biological monitoring of mistry of the Polish Academy of Sciences. nitrogen deposition by means of lichen". Warsaw, Poland: "Single and double intramo lecular proton transfer processes in hctcroaro- Dr M.H. Tliiemcns, Department of Chemistry, matics excited to the S} and T ales". U.C. San Diego. La Jolla. USA: "New isotope effects: Application to atmospheric chemistry, P. Hofrander. Svaiof AB, Sweden: "Use of chemicals physics and the origin of the solar antisense RNA changing starch of potatoes". system". S. Kannaiyan, King's College. London: "Nitro P. Uhskor. Institute of Plant Biology. The gen fixing potential of the Azolla-Anabacna Royal Veterinary and Agricultural University: complex and their utilization as hiofcrtilizcrs "Regulation of elongation growth in pea". for rice". Dr C. Zeizsch. Frauhofcr Institut. Hannover, Dr T. Konishi, Institute of Genetic Resources. Germany: "Photochemical degradation of aro Faculty of Agriculture. Kyushu University. matics by OH in the troposphere: Detailed Japan: "Application of Isozyme Technology to investigation of the mechanism". Barley Breeding". Dr R.B. Mellor. Botanisches Institut der Uni- versitåt Basel: "Plant reactions to endosymbio- sis at the molecular and organelle level". Drs M. Micke and V. Viiele, Institut fiir Pflan- zenzuchtung. Giilzow, Mecklenburg. Germany: Transfer of resistance gene from Hordeum bulbosum to barley varieties". J.M. Møller, Department of Plant Physiology. University of Lund. Sweden: "Plant Mitochon dria". 76 Riso-R-624(EN) 15 Committee Memberships 15.1 National 15.2 International Aarkrog, A. Danish Contact Forum for Health Aarkrog, A. IAEA CRP MARDOS. (Chair Physics. man). Danish National Council for Oceanology. IAEA VAMP programme. (Consultant). Danish reference group for CECs MAST CGC for CECs Radiation Protection Pro programme. gramme. Danish reference group for CECs Radiation Reference group NKS-RAD Programme. protection programme. Group to evaluate the Research Programme Andersen, A.J. Member of the board of Paj- on Radioactive Fallout of the Norwegian bjergfonden. Agricultural Research Counsil. Dahlgaard, H. Greenland Sea Project. Danish Editorial Board of J. Environ. Radioactivity. working group. Dahlgaard H. Baltic Marine Environment Giese, H- Member of The Danish Agricultural Protection Commission. Helsinki Commis and Veterinary Research Council. sion (HELCOM). Group of Experts on Mo Member of the board of The Institute of nitoring of Radioactive Substances in the Farm Management. Baltic Sea (MORS) Marine Radioecology Danish Society for the Conservation of Working Group (MARECO), International Nature. Committee for Environmental Issues. Union of Radioecologists (IUR). (Working Gissel-Sielsen. G. Vice chairman of The Da Group Leader). nish Agricultural and Veterinary Research Working Group on a Nordic participation in Council. the World Ocean Circulation Experiment. Member of the board of the Danish Academy (WOCE) of Technical Sciences. Nordic Nuclear Safety Project (NKS), Ra- Member of the board of the National dioccology programme (RAD). (Coordina Research Service for Soil and Plant Sciences. tor). Danish Society for the Conservation of Engyild. K.C. Member of Journal Committee Nature. Committee for Environmental Issues. of 'Physiologia Plantarutn'. Jørgensen, J.H. Dansk Genbanknævn. Gissel-Sielsen. G. OECD committee for plant/ Koordineringsgruppen for resistens og viru soiL microbial interactions. lens i korn og kornsygdomme. Jakobsen, 1. Management committee for COST Miller, A. Danish Utensil Producer Organisa Action 810: The role of VA-mycorrhizae in tion (DUFO). Sterilization committee. transformation of matter in the soil and their Sielsen, O.J. The National Committee for The importance for plant nutrition and plant International Gcosphcre-Biospherc Program health. me (IGBP). Jensen, E.S. Editorial Board of 'Plant and Soil'. Pilegaard, K. Danish Centre for Atmospheric Scctionboard for Soils and Fertilizers. Scan Research (DCAR) Working Group on effects. dinavian Association of Agricultural Scien (Chairman). tists. Solgaard, P. Dansk Standardiserings Råd. Jensen. J. International coordinator, barley Sl68-VandundcrsogeIse, FaU 213 chromosome 5; International Barley Nomen clature Committee. Risc-R-624(EN) 77 Jensi B. Skytte. Working Groups within the \ielsen, T. The board of Nordic Society of EEC R&D Programme Management and Aerc-so!s (NOSA). Storage of Radioactive Waste (MIRAGE), in S'tehen, S.P. international Committee on Ra the subcommittes CHEMVAL, COCO, and dionuclide Metrology. Natural Analogues. Articles 35 and 36 of the Euratom Treaty Member of WP Geological Disposal of Ra (Environmental Monitoring). dioactive Waste. The Editorial Board of Roed, J. The Group on in-situ measurements 'Waste Management". (1CRU). Jørgensen. J.H. Editorial board of "Euphytica'. IAEA and EEC VAMP Project Urban Group. International coordinator, disease and pest (Chairman). resistance genes. The Fuel Cycle Safety Group (OECD). Working group on cereal disease resistance SCOPE RADPATH. biology, Scandinavian Association of Agri Skou, J.P. Section for Plant Protection (Chair cultural Scientists. man), Scandinavian Association of Agricul Working group cereal, Nordic Gere Bank. tural Scientists. (Chairman). Wilbrondu R International Organization Com Working group barley, European Coordinated mittee on the Conference of Time-resolved Programme Genetic Resources. Vibrational Spectroscopy, Tokyo, Japan. Coordinating Committee. International Barley International Organization Committee on the Genetics Resources Network. Conference on the Spectroscopy of Biologi Runzendorf. H. Editorial Board of Marine cal Molecules, York. England. Mining'. Member of the Board of the 'International Marine Minerals Society*. Member of the planning group for a new Technologic Center for Marine Minerals. 16 Seminars Organized Reviewer of Marine Chemistry, Marine Geo 15 logy, Marine Mining. Mincraiium Deposita. COST 810 workshop, The Use of N Metho dology in Studies on the ROLE OF VA-My- Linde-Laursen, I. Editorial Board of Plant conhizas in N Cycling". December 5-6, 1991 Systematics and Evolution. (/. Jacobsen). Miller, A. American Society for Testing and Materials: Subcommittee E10.01: Dosimetry for Radiation Processing. RFLP course for Danish Plant Breeders. Sec Editorial Board of Radiation Physics and tion of Plant Biology, December 2-5, 1991 Chemistry (Pcrgamon Press). (Henri me Giese). Editorial Board of Radiation Sterilization (Israel). Danish Biochemical Society meeting: Enzymes in Plant Pathogen Resistance. March 12, 1991. Programme Committee, Int. Meeting on Ra (Søren Rasmussen). diation Processing. Beijing, 1992. Committee. Science Council, Beta Tech AB, Jonkoping, Sweden. Nielsen, O.J. COST-611 Conccrtation Com mittee on Physico-Chemical Behaviour of Atmospheric Pollutants. COST-611 Working Party 2 Steering Com mittee, Atmospheric and Photochemical Pro cesses. 78 Risø-R-624(EN) 17 Personnel The list abo include short term employees Head of Department Arne Jensen 17.1 Scientific Staff Rasmussen. Soren Roed. Jorn Aarkrog. Asker Rosendahl. Lis Andersen. Ama J. Sehested. Knud Berenstein, Dvora Sillesen. Alfred Heegaard Bjergbakke, Erling Skou. Jens Peder Bjerre. Anne Belinda Solgaard. Per Christiansen. Solveig Krogh Sorensen. Emil Dahlgaard. Henning Wilbrandt. Robert Doll.~Hans Ostcrgård. Hanne Ellermann. Thomas Engvild. Kjeld C Fenger. Jorgcn 17.2 Tehnical Staff Giese. Henriette Gissel Nielsen. Gunnar Andersen. Margit Elm Gundersen. Vagn Andersen. Bente Haahr. Vågner Andersen. Fritz Hansen. Heinz J.M. Andersen. Lis Brandt Hansen. Knud B. Andersen. Esther Holcman. Jerzy Baade-Pedcrsen. Pearl Holme. Inger Bitsch. Gunnar Jakobsen, her Brandstrup. Oda Jensen. Jens Brink Jensen. Merete Jensen. Hans Peter Christensen. Tove Jensen. Erik Steen Clausen. Jytte Lene Jensen. Bror Skytte Corfitzen. Hanne Jorgensen. Jorgcn Helms Djurdjcvic. Stanko Jørgensen. Rikke Bagger Dyrgaard Jensen. Lone Klåning. Ulrik Ebling. Elise Koie. Bertel Fernqvist. Tomas Kunzendorf, Helmer Gade. Poul Larsen, Else Toftdahl Green. Jytte Linde-Laursen. Ib Hansen, Carl Lynggård. Bent Hansen. Ina Mathiassen. Henrik Hansen. Elly Miller. Arne Hasselbalch, Finn Nielsen. Sven P. Henriksen. Ebbe Nielsen. Ole John Holm-'Jensen. Anne Grethe Nielsen. Torben Holm^Pedcrsen. Anna Nilsson. Karen Hougaard. Henrik Pagsbcrg. Palle Hogh. Mikael Pilegaard, Kim Ibsen Elly Risø-R-624(ES) 79 Jensen. Hanne Jacobsen. Inger Jensen. Ellen Moller KPvh. Tonny Jensen. Karen Mandrup Kornerup. Berit Johansen. Hanne Bay Kristensen. Ingrid Johansen Torben Krogh. Helle Jørgensen. Ole Larsen. Åse Ncve Jørgensen. Vibeke Madsen. Ruth Karlsen. Aage Nielsen. Margit Kjolhede. Alice Petersen. Lis Kristiansen. Bo Sørensen. Anni Larsen. Hanne Egerup Larsen. Inge Merete Larsen. Ingclis 17.4 Ph.D. Students Larsen. Fritz Larsen, Erik Engholm Andersson. Kasper Grann Lilholt. Ulla Bertelsen. Finn Lindskou. Fini Borbyc, Lisbeth Madsen. Michael Birch Carlsen. Søren Meltofte. Liselotte Eiicrmann. Thomas Mundt. Helge Chr. Frank Maiken Munk. Jette Johansen. Anders Nielsen. Jette Bruun Lange. Christian Nielsen. Vagn Aage Larsen. Else Toftdahl Nielsen. Svend Løgager. Tina Nikolajsen, Anette Moller. Sorcn Olsen. Svend K. Olsen. Allan Gylling Olsen. Inge Pedersen. Jesper Olsen. Anctrc Pedersen. Carsten Petersen. Susanne Pedersen. Lars H. Poulsen. Aksel Petersen. Lene Prip. Henrik Rasmussen. Ulla Rasmussen. Charlotte Rasmussen. Merete Sillesen. Anciikkc Sehested. Jens Skovsgaard. Bent Skov. Elise Sørensen. Poul Sorcnscn. Peter Thomsen. Jorgen D. Strandberg. Morten Vcstcscn. Hans ThciUJc. Bodil Vinther. Lis Øhlenschlæger. Mette Vinther. Niels Wie Nielsen. Karen Wojtaszewski. Hanne 17.5 M.Sc. Students Justesen, Annemarie 17.3 Office Staff Kollmg. Bent Quanrcoo, Eric Andersen. Annie Hansen. Torben Michael Bay, Kirsten Jacobsen. Frank 80 Kjærsgaard, Ulrik Suhr, Marianne Thomsen, Susanne Brun 17.6. Apprentices Hansen, Dorthe Thil Hansen, Trine Jensen, Christina Falk Jensen, Ulrik Soby Jensen, Thomas Nygaard Jensen, Ulla Damm Lauritzen, Lisbeth Oreskov, Sisse Tung, Tran Duc Jensen, Lene Korgaard, Charlotte Riso-R-624(EN) 18 Acronyms AA: Atomic Absorption BIOMOVS: Biosphcric Model Validation Study BMC: Baltic Marine Cooperation BNN: Bureau National de Metrologie CFC: Commission of European Communities CGC: Management ar.d Coordination Advisory Committee CRESP: Coordinated Research and Environmental Surveillance Programme (under NEA) DCAR: Danish Centre for Atmospheric Research DH: Chromosome-Doubled Haploid DKD: Deutscher Kalibrierdienst DIA: Denmarks Academy for Engineering DNA: Dioxyribonucleicacid DOAS: Differential Optical Absorption Spectroscopy DTH: Technical University of Denmark EC: European Communities EDX: Energy dispersion X-ray fluoroscence spectrometry EEC: European Economic Communities ETV: Electrothermal Vaporisator EUROTRAC: European Experiment on Transport and Transformation of Environmental Relevant Trace Constituents of Anthropogenic and Natural Origin FATE: Formation of Aerosol and their Transformation over Europe (under EUROTRAC) FLAIR: Measurement of Micronutricnt Absorption and Status GMP: Genetically Modified P.ants GRECA: Group of Experts on accident Consequences (under NEA. OECD) GSF: Gcscllschaft i'ur Strahlcii - und Umweltforschung GSP: Greenland Sea Project HELCOM: Helsinki Commission HDRL: High Dose Reference Laboratory IAEA: International Atomic Energy Agency IBSS: Institute of Biology of the Southern Seas (USSR) 1C: Ionchromatography ICP/MS: Inductively Coupled Plasma Mass Spectromety ICARDA: International Center for Agricultural Research in the Dry Areas ICRM: International Commitee on Radionuclide Metrology ICRU: International Commission on Radiological Units IFE: Institute for Energy Technology Norway IUR: International Union of Radioecologists IVL: Swedish Environmental Research Institute MARDOS: IAEA CRP on "Sources of Radioactivity in the Marine Environment and their Rela tive Contributors to Overall Dose Assessment from Marine Radioactivity" MARECO: Marine Radioecoiogy Working Group (under IUR) MARIA: Methods for Assessing ,he Radiological Impact of A jidents. (Reseaxh programme under CEC) MAST: Marine Science and Technology Programme (under CEC) MODECS: Molecular Design of Chemical Systems MORS: Group of Experts Monitoring of Radioactive Substances in the Baltic Sea NAMAS: National Measurement Accreditation Service NEA: Nuclear Energy Agency (under OECD) 82 Risø-F-624(EW) NERI: National Environmental Research Institute NGB: Nordic Gene Bank NKA: Nordic Liason Committee for Atomic Energy NKO: Nedcrlandsc Kalibratie Organisatie NKS: Nordic Nuclear Safety Project NLV'F: Norway Agricultural Research Council NZOI: New Zealand Oceanographic Institute OECD: Organisation for Economic Cooperation and Development PAH: Poly Aomatic Hydrocarbons PBM: Peribac eroid Membrane PBU: Pcribacteroid Unit PCR: Polymerase Chain Technologi PMC: Pollen Mother Cell QTL: Quantitative Trait Loci RAD: Radioecology Programme (under NKS) RAPD: Random Amplified Polymorphic DNA Technique RADPATH: Biochemical Pathways of Artificial Radionuclides (under CEC) RESSAC: The Consequence of a Major Nuclear Accident on the Surrounding Environment: Soil and Surface Rehabilitation (under C»EC) RFLP: Restriction Fragment Length Polymorphism RIMI: Riso Integrated Environmental Project RUC: Roskilde University Center RVAU: The Royal Veterinary and Agricultural University SCOPE: Scientific Committee on Problems of the Environment (under International Council of Scientific Unions: (ICSU)) SCS: Swiss Calibration Service SIT: Servizio di Taratura in Italia SJVF: Veterinary Agricultural Research Council SWEDAC: Swedish Board for Technical Accreditation TOR: Troposphcric Ozone Research (under EUROTRAC) UKAEA: United Kingdom Atomic Energy Authorities VAM: Vesicular-Arbuscular Mycorrhiza VAMP: Validation of Model Project (under IAEA) WECC: Western European Calibration Cooperation WOCE: World Ocean Circulation Experiment Risø-R-624(EN) 83 Bibliographic Data Sheet Risø-R-624(EN) Title and M: thoKO Environmental Science and Technology Department Annual Report 1991 Edited by A. Jensen, V. Gunderson, H. Hansen, G Gissel Nielsen, O.J. Nielsen and H. Østergård ISBN ISSN 87-550-1806-8 0106-2840 0906-8090 DcpL or group Date Environmental Science and Technology Department June 1992 Groups own rcf. nurobcr(i) Projcct/coniract no(s) Paget Tablet Illustrations Rcfcrcncn 84 23 58 Abstract (Max. 2000 characters) Selected activities in the Environmental Science and Technology Department during 1991 are presented. The research approach in the depart ment is predominantly experimental. The re search topics emphasized are introduced and re viewed in chapters one to seven: 1. Introduction, 2. The Atmosphere, 3. Plant Genetics and Resis tance Biology, 4. Plant Nutrition, 5. Geochemi stry, 6. Ecology, 7. Other activities. The Depart ment's contribution to national and international collaborative research programmes is presented together with information about large facilities managed and used by the department. Informa tion about the department's education and train ing activities are included in the annual report along with lists of publications, publications in press, lectures and poster presentations. Further, names of the scientific and technical staff mem bers, Ph.D. students and visitiing scientists are listed. Descriptor« INIS/EDB AIR POLLUTION; ATMOSPHERIC CHEMISTRY; CHEMICAL ANALYSIS; DISEASE RESISTANCE; ECOSYSTEMS; GENETICS; GEOCHEMISTRY; NUTRITION; PLANTS; PROGRESS REPORT; RADIOECOLOGY; RESEARCH PROGRAMS; R1S0E NATIONAL LABORATORY Available on request from Rise Library, Ris« National Laboratory, (RiM Bibliotek, Fonkninpcenicr RiacO, P.O.Box 49, DK-4000RotkUdc, Denmark. Telephone + 45 42 3712 12, at 2261/2269 Tela 4J 116. Telek« * 45 46 75 56 27. Available on request from: Risø Library Risø National Laboratory, P.O. Box 49, DK-4000 Roskilde, Denmark ISBN 87-550-1806-8 Phone + 45 42 37 12 12, ext. 2268/2269 ISSN 0106-2840 Telex 43 116, Telefax + 45 46 75 56 27 ISSN 0906-8090