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Title: Pharmaceuticals, hormones, and other organic wastewater contaminants in US streams, 1999-2000: A national reconnaissance Author(s): Kolpin DW, Furlong ET, Meyer MT, Thurman EM, Zaugg SD, Barber LB, Buxton HT Source: ENVIRONMENTAL SCIENCE & TECHNOLOGY 36 (6): 1202-1211 MAR 15 2002 Document Type: Article Language: English Cited References: 63 Times Cited: 370 Abstract: To provide the first nationwide reconnaissance of the occurrence of pharmaceuticals, hormones, and other organic wastewater contaminants (OWCs) in water resources, the U.S. Geological Survey used five newly developed analytical methods to measure concentrations of 95 OWCs in water samples from a network of 139 streams across 30 states during 1999 and 2000. The selection of sampling sites was biased toward streams susceptible to contamination (i.e. downstream of intense urbanization and livestock production). OWCs were prevalent during this study, being found in 80% of the streams sampled. The compounds detected represent a wide range of residential, industrial, and agricultural origins and uses with 82 of the 95 OWCs being found during this study. The most frequently detected compounds were coprostanol (fecal steroid), cholesterol (plant and animal steroid), N,N-diethyltoluamide (insect repellant), caffeine (stimulant), triclosan (antimicrobial disinfectant), tri(2-chloroethyl)phosphate (fire retardant), and 4-nonylphenol (nonionic detergent metabolite). Measured concentrations for this study were generally low and rarely exceeded drinking-water guidelines, drinking-water health advisories, or aquatic-life criteria. Many compounds, however, do not have such guidelines established. The detection of multiple OWCs was common for this study, with a median of seven and as many as 38 OWCs being found in a given water sample. Little is known about the potential interactive effects (such as synergistic or antagonistic toxicity) that may occur from complex mixtures of OWCs in the environment. In addition, results of this study demonstrate the importance of obtaining data on metabolites to fully understand not only the fate and transport of OWCs in the hydrologic system but also their ultimate overall effect on human health and the environment. KeyWords Plus: IN-GROUND WATER; SURFACE WATERS; DRUG RESIDUES; ANTIBIOTICS; ENVIRONMENT; PESTICIDES; SEWAGE; FISH; CIPROFLOXACIN; SPECTROMETRY Addresses: Kolpin DW (reprint author), US Geol Survey, 400 S Clinton St,Box 1230, Iowa City, IA 52244 USA US Geol Survey, Iowa City, IA 52244 USA US Geol Survey, Denver, CO 80225 USA US Geol Survey, Ocala, FL 34474 USA US Geol Survey, Lawrence, KS 66049 USA US Geol Survey, Boulder, CO 80303 USA US Geol Survey, W Trenton, NJ 08628 USA Publisher: AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 USA Subject Category: ENGINEERING, ENVIRONMENTAL; ENVIRONMENTAL SCIENCES

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Review Notes Title: A mixing model analysis of stream solute dynamics and the contribution of a hyporheic zone to ecosystem function Author(s): Battin TJ, Kaplan LA, Newbold JD, Hendricks SP Source: FRESHWATER BIOLOGY 48 (6): 995-1014 JUN 2003 Document Type: Article Language: English Cited References: 58 Times Cited: 3 Abstract: 1. We monitored streamwater and streambed sediment porewaters from White Clay Creek (WCC), SE Pennsylvania, for dissolved organic carbon (DOC), dissolved oxygen (DO) and conductivity to investigate organic matter processing within the hyporheic zone. Dissolved organic carbon and DO concentrations were higher in the streamwater than in the porewaters and, in many cases, concentrations continued to diminish with increasing depth into the streambed. 2. Hydrological exchange data demonstrated that the permeability of the stream bed declines with depth and constrains downwelling, effectively isolating porewaters >30 cm from streamwater. 3. End-member mixing analysis (EMMA) based on conductivity documented a DOC source and DO sink in the hyporheic zone. We calculated hyporheic streambed DOC fluxes and respiration from the EMMA results and estimates of water flux. Based upon our calculations of biodegradable DOC entering the hyporheic zone, we estimate that DOC supports 39% of the hyporheic zone respiration, with the remaining 61% presumably being supported by entrained particulate organic carbon. Hyporheic respiration averaged 0.38 g C m(-2) d(-1) , accounted for 41% of whole ecosystem respiration, and increased baseflow ecosystem efficiency from 46 to 59%. 4. Advective transport of labile organic molecules into the streambed concentrates microbial activity in near-surface regions of the hyporheic zone. Steep gradients in biogeochemical activity could explain how a shallow and hydrologically constrained hyporheic zone can dramatically influence organic matter processing at the ecosystem scale. Author Keywords: dissolved organic carbon; ecosystem function; end-member mixing analysis; hydrodynamic exchange; hyporheic zone KeyWords Plus: DISSOLVED ORGANIC-CARBON; VERTICAL HYDROLOGIC EXCHANGE; SURFACE-WATER; COMMUNITY RESPIRATION; BACTERIAL BIOMASS; HEADWATER STREAMS; TEMPERATE STREAM; MOUNTAIN STREAM; DESERT STREAM; METABOLISM Addresses: Kaplan LA (reprint author), Stroud Water Res Ctr, 970 Spencer Rd, Avondale, PA 19311 USA Stroud Water Res Ctr, Avondale, PA 19311 USA Hancock Biol Stn, Murray, KY USA Publisher: BLACKWELL PUBLISHING LTD, 9600 GARSINGTON RD, OXFORD OX4 2DG, OXON, ENGLAND Subject Category: MARINE & FRESHWATER BIOLOGY IDS Number: 679YA

Title: Modeling floodplain filtration for the improvement of river water quality Author(s): Chung JB, Kim SH, Jeong BR, Lee YD, Prasher S Source: TRANSPORT IN POROUS MEDIA 60 (3): 319-337 SEP 2005 Document Type: Article Language: English Cited References: 37 Times Cited: 0 Abstract: A mathematical model was developed to describe a treatment method of floodplain filtration for the improvement of river water quality. The process consists of spraying poor quality river water onto the river floodplains and thus allowing soil filtration to treat water before it gets back again into the main river stream. This technique can be readily employed in Korea because it exploits the characteristics of the climate and rivers in the country, as described in an experimental study of Chung et al. ( 2004). The model was analyzed by numerical methods and validated by comparing the simulated values with experimental data. A scenario analysis of the model was also performed in order to have a better understanding of the. oodplain filtration process. Our results show that the model was able to predict the reduction in organic matter and NO3- in river water through the. oodplain filtration. Furthermore, it was found that only a few decimeters of top soil profile were enough to degrade most of the organic matter under wider operational conditions than those reported in the literature. Also, it was found that significant infiltration of atmospheric oxygen took place near the soil surface. The N2O emission and the NO3- leaching increased with the increase in the influent NO3- concentration. However, the N2O emission due to. oodplain filtration was not expected to exceed 0.1 mL/m(2)-day.

Title: Field tracer tests on the mobility of natural organic matter in a sandy aquifer Author(s): McCarthy JF, Gu B, Liang L, MasPla J, Williams TM, Yeh TCJ Source: WATER RESOURCES RESEARCH 32 (5): 1223-1238 MAY 1996 Document Type: Article Language: English Cited References: 45 Times Cited: 23 Abstract: The field-scale transport of natural organic matter (NOM) was examined in a two-well forced gradient injection experiment in a sandy, coastal plain aquifer in Georgetown, South Carolina. Spatial moments described the migration of the center of mass of NOM and conservative tracer. Temporal moments were used to estimate mass loss and retardation of the NOM along a transect of six sampling locations at two depths and at the withdrawal well. Large differences were observed in transport behavior of different subcomponents of NOM. Larger and more strongly binding NOM components in the injection solution are postulated to adsorb and displace weakly binding, low-molecular weight NOM in groundwater. Conversely, NOM components that were similar to the groundwater NOM were transported almost conservatively, presumably due to ''passivation'' of the aquifer by previously adsorbed components of the groundwater NOM. NOM may thus exhibit two types of effects on contaminant dynamics in the subsurface. When the equilibria between solution and solid phase NOM is disrupted by introduction of a novel source of NOM, descriptions of the multicomponent transport process are complex and predictive modeling is problematic. Because of the differences in transport behavior of NOM subcomponents, the chemical properties and, more importantly, the functional behavior of NOM with respect to contaminant migration will vary with time and distance along a flow path. However, when groundwater NOM exists at a steady state with respect to adsorption on aquifer surfaces, the migration of NOM, and the contaminant-NOM complex, may be approximated as the transport of a conservative solute. KeyWords Plus: AQUEOUS-SOLUTIONS; ADSORPTION AFFINITY; UNKNOWN SUBSTANCES; POROUS-MEDIA; TRANSPORT; WATER; CARBON; MACROMOLECULES; EQUILIBRIUM; COLUMNS Addresses: McCarthy JF (reprint author), OAK RIDGE NATL LAB, DIV ENVIRONM SCI, POB 2008, OAK RIDGE, TN 37831 USA UNIV AUTONOMA BARCELONA, DEPT GEOL, BARCELONA, E-08193 SPAIN CLEMSON UNIV, BARUCH FOREST SCI INST, CLEMSON, SC 29631 USA UNIV ARIZONA, DEPT HYDROL & WATER RESOURCES, TUCSON, AZ 85721 USA Publisher: AMER GEOPHYSICAL UNION, 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 Subject Category: ENVIRONMENTAL SCIENCES; LIMNOLOGY; WATER RESOURCES

Title: The simultaneous modelling of metal ion and humic substance transport in column experiments Author(s): Bryan ND, Barlow J, Warwick P, Stephens S, Higgo JJW, Griffin D Source: JOURNAL OF ENVIRONMENTAL MONITORING 7 (3): 196-202 2005 Document Type: Article Language: English Cited References: 29 Times Cited: 0 Abstract: Pulsed column experiments using Co, fulvic acid and porous sediment packing, along with up/down-flooding experiments using Eu, humic acid and intact sandstone blocks have been performed. The elution of metal and humic and their distribution along the sandstone columns have been measured. A mixed equilibrium and kinetic coupled chemical transport model has been used to simulate the results. In both cases, one exchangeable and one non-exchangeable component have been used to simulate the interaction of metal and humic substance. For the pulsed experiments, a simple equilibrium approach was used to model humic sorption, while a two component, kinetic model was required for the sandstone columns. KeyWords Plus: NATURAL ORGANIC-MATTER; IRON-OXIDE; COMPETITIVE ADSORPTION; SANDY AQUIFER; DESORPTION; SORPTION; ACIDS; DISPLACEMENT; PARTICLES; MOBILITY Addresses: Bryan ND (reprint author), Univ Manchester, Dept Chem, Ctr Radiat Res, Oxford Rd, Manchester, Lancs M13 9PL England Univ Manchester, Dept Chem, Ctr Radiat Res, Manchester, Lancs M13 9PL England Univ Loughborough, Dept Chem, Loughborough, Leics England British Geol Survey, Keyworth, Notts NG12 5GG England RMC Ltd, Abingdon, Oxon England Publisher: ROYAL SOC CHEMISTRY, THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND Subject Category: ENVIRONMENTAL SCIENCES

Title: Modeling transport of a mixture of natural organic molecules: Effects of dynamic competitive sorption from particle to aquifer scale Author(s): van de Weerd H, van Riemsdijk WH, Leijnse A Source: WATER RESOURCES RESEARCH 38 (8): Art. No. 1158 AUG 27 2002 Document Type: Article Language: English Cited References: 34 Times Cited: 0 Abstract: [1] Natural organic matter ( NOM) can act as a carrier for contaminants. Therefore it is of great importance to understand its adsorption/desorption and transport behavior. NOM is a mixture of molecules varying from simple small molecules like citric acid to complicated large molecules like humic acid. To simulate sorption and transport of NOM in aquifer material, we used a previously developed model ( NOMADS) describing the dynamic competitive sorption of NOM fractions. We calibrated NOMADS using independent batch adsorption data and incorporated it in a transport code. Sorption and transport of NOM in laboratory column experiments and a field experiment were well simulated using the calibrated model, indicating that the process descriptions used are valid over a wide range of temporal and spatial scales and mass-to-volume ratios. Simulation results provided insights into the influence of pore water velocity and NOM concentration history on the shape of breakthrough curves of NOM fractions. The heterogeneity of NOM appears to be essential to understanding its adsorption and transport behavior. Author Keywords: NOM; natural organic matter; mixture; sorption; competition; transport KeyWords Plus: REACTIVE SOLUTE TRANSPORT; CONTAMINATED SANDY SOIL; POROUS-MEDIA; IRON-OXIDE; IMMOBILE SORBENTS; HUMIC SUBSTANCES; ADSORPTION; MATTER; CARBON; MOBILITY Addresses: van de Weerd H (reprint author), Univ Wageningen & Res Ctr, Dept Environm Sci, Aquat Ecol & Water Qual Management Grp, POB 8080, Wageningen, NL- 6700 DD Netherlands Univ Wageningen & Res Ctr, Dept Environm Sci, Subdept Water Resources, Wageningen, Netherlands Univ Wageningen & Res Ctr, Dept Environm Sci, Subdept Soil Qual, Wageningen, NL- 6700 EC Netherlands Netherlands Inst Appl Geosci TNO, Geoenvironm Dept, Utrecht, NL-3508 TA Netherlands Publisher: AMER GEOPHYSICAL UNION, 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA Subject Category: ENVIRONMENTAL SCIENCES; LIMNOLOGY; WATER RESOURCES IDS Number: 622JR

Title: Controls on the dynamics of dissolved organic matter in soils: A review Author(s): Kalbitz K, Solinger S, Park JH, Michalzik B, Matzner E Source: SOIL SCIENCE 165 (4): 277-304 APR 2000 Document Type: Review Language: English Cited References: 237 Times Cited: 125 Abstract: Dissolved organic matter (DOM) in soils plays an important role in the biogeochemistry of carbon, nitrogen, and phosphorus, in pedogenesis, and in the transport of pollutants in soils. The aim of this review is to summarize the recent literature about controls on DOM concentrations and fluxes in soils. We focus on comparing results between laboratory and field investigations and on the differences between the dynamics of dissolved organic carbon (DOC), nitrogen (DON), and phosphorus (DOP). Both laboratory and field studies show that litter and humus are the most important DOM sources in soils. However, it is impossible to quantify the individual contributions of each of these sources to DOM release. In addition, it is not clear how changes in the pool sizes of litter or humus may affect DOM release. High microbial activity, high fungal abundance, and any conditions that enhance mineralization all promote high DOM concentrations. However, under field conditions, hydrologic variability in soil horizons with high carbon contents may be more important than biotic controls. In subsoil horizons with low carbon contents, DOM may be adsorbed strongly to mineral surfaces, resulting in low DOM concentrations in the soil solution. There are strong indications that microbial degradation of DOM also controls the fate of DOM in the soil. Laboratory experiments on controls of DOM dynamics have often contradicted field observations, primarily because hydrology has not been taken into account. For example, laboratory findings on the effects of plant species (conifer vs. deciduous) on DOM release from forest floors and on the effects of substrate quality (e.g.: C/N ratio) or pH on DOC concentrations were often not confirmed in field studies. The high adsorption capacity of soil clay minerals and oxides for DOM shown in laboratory studies may not control the transport of DOM in soils in the field if macropore fluxes dominate under field conditions. Laboratory findings about the biodegradability of DOM also await verification under field conditions. Studies that include DON and DOP dynamics in addition to DOC are few. The rate of release and the fate of DOG, DON, and DOP in soils may differ to a far greater extent than previously assumed. Controls established for DOC might thus be not valid for DON and DOP. Despite intensive research in the last decade, our knowledge of the formation and fate of DOM in soils and its response to changing environmental conditions is still fragmented and often inconsistent. Predictions at the field scale are still very uncertain, and most of the information available today is the result of studies on temperate soils and forest ecosystems. Thus, future research on controls of DOM dynamics should be extended to soils under different land uses and in other climate zones. Emphasis should also be given to: (i) the effects of soil organic matter properties on the release of DOM (ii) environmental factors controlling DOM quantity and quality (iii) the assessment of biological versus physico-chemical controls on the release and retention of DOM in soils, and (iv) the differences between DOG, DON, and DOP. Finally, if our goal is to predict DOM concentrations and fluxes in soils, future research on the controls of DOM dynamics should have a strong focus on field studies. Author Keywords: dissolved organic matter (DOM); dissolved organic carbon (DOC); dissolved organic nitrogen (DON); dissolved organic phosphorus (DOP); soils; controls KeyWords Plus: ACID FOREST SOILS; CALIFORNIA AGRICULTURAL SOILS; WHEAT STRAW DECOMPOSITION; SANDY PRAIRIE SOIL; SOLUTION CHEMISTRY; HUMIC SUBSTANCES; CARBON CONCENTRATIONS; NUTRIENT DYNAMICS; CONIFEROUS FOREST; STREAM WATER Addresses: Kalbitz K (reprint author), Univ Bayreuth, BITOK, Inst Terr Ecosyst Res, Dept Soil Ecol, Dr Hans Frisch Str 1-3, Bayreuth, D-95440 Germany Univ Bayreuth, BITOK, Inst Terr Ecosyst Res, Dept Soil Ecol, Bayreuth, D-95440 Germany Publisher: LIPPINCOTT WILLIAMS & WILKINS, 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA Subject Category: AGRICULTURE, SOIL SCIENCE IDS Number: 309MY ISSN: 0038-075X

Title: Transformation of organic matter and bank filtration from a polluted stream Author(s): Cosovic B, Hrsak D, Vojvodic V, Krznaric D Source: WATER RESEARCH 30 (12): 2921-2928 DEC 1996

Title: ADSORPTION BEHAVIOR OF THE HYDROPHOBIC FRACTION OF ORGANIC- MATTER IN NATURAL-WATERS Author(s): COSOVIC B, VOJVODIC V Source: MARINE CHEMISTRY 28 (1-3): 183-198 DEC 1989

Title: HUMUS TRANSFORMATION AT THE BANK FILTRATION WATER-PLANT Author(s): MIETTINEN IT, MARTIKAINEN PJ, VARTIAINEN T Source: WATER SCIENCE AND TECHNOLOGY 30 (10): 179-187 1994 Document Type: Article Title: Removal of organic matter and nitrogen from river water in a model floodplain Author(s): Chung JB, Kim SH, Jeong BR, Lee YD Source: JOURNAL OF ENVIRONMENTAL QUALITY 33 (3): 1017-1023 MAY-JUN 2004 Document Type: Article Language: English Cited References: 26 Times Cited: 1 Abstract: A significant improvement in river water quality cannot be expected unless nonpoint-source contaminants are treated in addition to the further treatment of point- source contaminants. If river water is sprayed over a floodplain, the consequent water filtration through the sediment profile can simultaneously remove organic matter and nitrogen in the water through aerobic and denitrifying reactions. This hypothesis was tested using lysimeters constructed from polyvinyl chloride (PVC) pipe (150 cm long, 15 cm in diameter) packed with loamy sand floodplain sediment. Water was applied to the top of the lysimeters at three different flow rates (48, 54, and 68 mm d(-1)). Concentrations of NO3 and dissolved oxygen (DO), chemical oxygen demand (COD), and redox potential (Eh) in the water were measured as functions of depth after the system reached steady states for both water flow and reactions. At the rate of 68.0 mm d(-1), a reducing condition for denitrification developed below the 5-cm depth due to the depletion of 02 by organic matter degradation in the surface oxidizing layer; Eh and DO were below 205 mV and 0.4 mg L-1, respectively. At a depth of 70 cm, COD and NO3-N concentration decreased to 5.2 and 3.8 mg L-1 from the respective influent concentrations of 17.1 and 6.2 mg L-1. Most biodegradable organic matter was removed during flow and further removal of NO3 was limited by the lack of an electron donor (i.e., organic matter). These results indicate that the floodplain filtration technique has great promise for treatment of contaminated river water.

Title: Effect of dissolved organic matter and bacteria on contaminant transport in riverbank filtration Author(s): Kim SB, Corapcioglu MY, Kim DJ Source: JOURNAL OF CONTAMINANT HYDROLOGY 66 (1-2): 1-23 OCT 2003 Document Type: Article Language: English Cited References: 64 Times Cited: 1 Abstract: A mathematical model for the transport of hydrophobic organic contaminants in an aquifer under simplistic riverbank filtration conditions is developed. The model considers a situation where contaminants are present together with dissolved organic matter (DOM) and bacteria. The aquifer is conceptualized as a four-phase system: two mobile colloidal phases, an aqueous phase, and a stationary solid phase. An equilibrium approach is used to describe the interactions of contaminants with DOM, bacteria, and solid matrix. The model is composed of bacterial transport equation and contaminant transport equation. Numerical simulations are performed to examine the contaminant transport behavior in the presence of DOM and bacteria. The simulation results illustrate that contaminant transport is enhanced markedly in the presence of DOM and bacteria, and the impact of DOM on contaminant mobility is greater than that of bacteria under examined conditions. Sensitivity analysis demonstrates that the model is sensitive to changes of three lumped parameters: K-1(+) (total affinity of stationary solid phase to contaminants), K-2(+) (total affinity of DOM to contaminants), and K-3(+) (total affinity of bacteria to contaminants). In a situation where contaminants exist simultaneously with DOM and bacteria, contaminant transport is mainly affected by a ratio of K-1(+)/K- 2(+)/K-3(+), which can vary with changes of equilibrium distribution coefficient of contaminants and/or colloidal concentrations. In riverbank filtration, the influence of DOM and bacteria on the transport behavior of contaminants should be accounted to accurately predict the contaminant mobility. (C) 2003 Elsevier Science B.V. All rights reserved. Author Keywords: riverbank filtration; hydrophobic organic contaminant; dissolved organic matters; bacteria; colloid-facilitated transport KeyWords Plus: POLYNUCLEAR AROMATIC-HYDROCARBONS; NATURAL POROUS- MEDIA; ALLUVIAL AQUIFER; FACILITATED TRANSPORT; MOBILE BACTERIA; BANK FILTRATION; LABORATORY COLUMN; AQUATIC SYSTEMS; SURFACE WATERS; GROUNDWATER Addresses: Kim SB (reprint author), Korea Univ, Dept Earth & Environm Sci, Seoul, 136701 South Korea Korea Univ, Dept Earth & Environm Sci, Seoul, 136701 South Korea Texas A&M Univ, Dept Civil Engn, College Stn, TX 77843 USA

Title: Contaminant transport in riverbank filtration in the presence of dissolved organic matter and bacteria: a kinetic approach Author(s): Kim SB, Corapcioglu MY Source: JOURNAL OF HYDROLOGY 266 (3-4): 269-283 SEP 15 2002 Document Type: Article Language: English Cited References: 25 Times Cited: 0 Abstract: In riverbank filtration, the removal of organic contaminants is an important task for the production of good quality drinking water. The transport of an organic contaminant in riverbank filtration can be retarded by sorption on to the solid matrix and facilitated by the presence of mobile colloids. In the presence of dissolved organic matter (DOM) and bacteria, the subsurface environment can be modeled as a four-phase porous medium: two mobile colloidal phases, an aqueous phase, and a solid matrix. In this study, a kinetic model is developed to simulate the contaminant transport in riverbank filtration in the presence of DOM and bacteria. The bacterial deposition and the contaminant sorption on bacteria and DOM are expressed with kinetic expressions. The model equations are solved numerically with a fully implicit finite difference method. Simulation results show that the contaminant mobility increases greatly in riverbank filtration due to the presence of DOM. The mobility can be enhanced further when the bacteria and DOM are present together in the aquifer. In this system, the total aqueous phase contaminant concentration, C-ct(+) includes the contaminant dissolved in the aqueous phase, C-c(+) the contaminant sorbed to DOM, sigma(cd)(+), and the contaminant sorbed to mobile bacteria, C(b)(+)sigma(cbm)(+),(i.e. C-ct(+) = C-c(+) + sigma(cd)(+) + C-b(+) sigma(cbm)(+)) Sensitivity analysis illustrates that the distribution of the total aqueous phase contaminants among the dissolved phase, DOM and bacteria is changed significantly with various Damkohler numbers related to the contaminant sorption on mobile colloids. (C) 2002 Elsevier Science B.V. All rights reserved. Author Keywords: riverbank filtration; contaminant transport; colloids; dissolved organic matter; bacteria KeyWords Plus: GROUNDWATER-INFILTRATION; LABORATORY COLUMN; ALLUVIAL AQUIFER; MOBILE BACTERIA; POROUS-MEDIA; WATER; FIELD; HYDROCARBONS; SOLUBILITY; COLLOIDS Addresses: Kim SB (reprint author), Texas A&M Univ, Dept Civil Engn, College Stn, TX 77843 USA Texas A&M Univ, Dept Civil Engn, College Stn, TX 77843 USA Title: Contaminant transport in dual-porosity media with dissolved organic matter and bacteria present as mobile colloids Author(s): Kim SB, Corapcioglu MY Source: JOURNAL OF CONTAMINANT HYDROLOGY 59 (3-4): 267-289 DEC 2002 Document Type: Article Language: English Cited References: 33 Times Cited: 3 Abstract: In riverbank filtration, contaminant transport is affected by colloidal particles such as dissolved organic matter (DOM) and bacterial particles. In addition, the subsurface heterogeneity influences the behavior of contaminant transport in riverbank filtration. A mathematical model is developed to describe the contaminant transport in dual-porosity media in the presence of DOM and bacteria as mobile colloids. In the model development, a porous medium is divided into the mobile and immobile regions to consider the presence of ineffective micropores in physically heterogeneous riverbanks. We assume that the contaminant transport in the mobile region is controlled by the advection and dispersion while the contaminant transport in the immobile region occurs due to the molecular diffusion. The contaminant transfer between the mobile and immobile regions takes place by diffusive mass transfer. The mobile region is conceptualized as a four-phase system: two mobile colloidal phases, an aqueous phase, and a solid matrix. The complete set of governing equations is solved numerically with a fully implicit finite difference method. The model results show that in riverbank filtration, the contaminant can migrate further than expected due to the presence of DOM and bacteria. In addition, the contaminant mobility increases further in the presence of the immobile region in aquifers. A sensitivity analysis shows that in dual-porosity media, earlier breakthrough of the contaminant takes place as the volumetric fraction of the mobile region decreases. It is also demonstrated that as the contaminant mass transfer rate coefficient between the mobile and immobile regions increases, the contaminant concentration gradient between the two regions reverses at earlier pore volumes. The contaminant mass transfer coefficient between the mobile and immobile regions mainly controls the tailing effect of the contaminant breakthrough. The contaminant breakthrough curves are sensitive to changes in contaminant adsorption and desorption rate coefficients on DOM and bacteria. In situations where the contaminant is released in the presence of DOM and bacteria in dual-porosity media, the early breakthrough and tailing occur due to the colloidal facilitation and presence of immobile regions. (C) 2002 Elsevier Science B.V. All rights reserved. Author Keywords: riverbank filtration; dual-porosity media; mobile-immobile region; colloid-facilitated transport; colloids KeyWords Plus: POROUS-MEDIA; THEORETICAL DEVELOPMENT; FACILITATED TRANSPORT; SOLUTE TRANSPORT; GROUNDWATER; AQUIFER; MODEL; SOIL; HYDROCARBONS; BREAKTHROUGH Addresses: Kim SB (reprint author), Texas A&M Univ, Dept Civil Engn, College Stn, TX 77843 USA Texas A&M Univ, Dept Civil Engn, College Stn, TX 77843 USA

Title: Contaminant transport in riverbank filtration in the presence of dissolved organic matter and bacteria: a kinetic approach Author(s): Kim SB, Corapcioglu MY Source: JOURNAL OF HYDROLOGY 266 (3-4): 269-283 SEP 15 2002 Document Type: Article Language: English Cited References: 25 Times Cited: 0 Abstract: In riverbank filtration, the removal of organic contaminants is an important task for the production of good quality drinking water. The transport of an organic contaminant in riverbank filtration can be retarded by sorption on to the solid matrix and facilitated by the presence of mobile colloids. In the presence of dissolved organic matter (DOM) and bacteria, the subsurface environment can be modeled as a four-phase porous medium: two mobile colloidal phases, an aqueous phase, and a solid matrix. In this study, a kinetic model is developed to simulate the contaminant transport in riverbank filtration in the presence of DOM and bacteria. The bacterial deposition and the contaminant sorption on bacteria and DOM are expressed with kinetic expressions. The model equations are solved numerically with a fully implicit finite difference method. Simulation results show that the contaminant mobility increases greatly in riverbank filtration due to the presence of DOM. The mobility can be enhanced further when the bacteria and DOM are present together in the aquifer. In this system, the total aqueous phase contaminant concentration, C-ct(+) includes the contaminant dissolved in the aqueous phase, C-c(+) the contaminant sorbed to DOM, sigma(cd)(+), and the contaminant sorbed to mobile bacteria, C(b)(+)sigma(cbm)(+),(i.e. C-ct(+) = C-c(+) + sigma(cd)(+) + C-b(+) sigma(cbm)(+)) Sensitivity analysis illustrates that the distribution of the total aqueous phase contaminants among the dissolved phase, DOM and bacteria is changed significantly with various Damkohler numbers related to the contaminant sorption on mobile colloids. (C) 2002 Elsevier Science B.V. All rights reserved. Author Keywords: riverbank filtration; contaminant transport; colloids; dissolved organic matter; bacteria KeyWords Plus: GROUNDWATER-INFILTRATION; LABORATORY COLUMN; ALLUVIAL AQUIFER; MOBILE BACTERIA; POROUS-MEDIA; WATER; FIELD; HYDROCARBONS; SOLUBILITY; COLLOIDS Addresses: Kim SB (reprint author), Texas A&M Univ, Dept Civil Engn, College Stn, TX 77843 USA Texas A&M Univ, Dept Civil Engn, College Stn, TX 77843 USA

Title: Artificial recharge of humic ground water Author(s): Alborzfar M, Villumsen A, Gron C Source: JOURNAL OF ENVIRONMENTAL QUALITY 30 (1): 200-209 JAN-FEB 2001 Document Type: Article Language: English Cited References: 30 Times Cited: 0 Abstract: The purpose of this study was to investigate the efficiency of soil in removing natural organic matter from humic ground waters using artificial recharge. The study site, in western Denmark, was a 10 000 m(2) football held of which 2000 m(2) served as an infiltration held. The impact of the artificial recharge was studied by monitoring the water level and the quality of the underlying shallow aquifer, The humic ground water contained mainly humic acids with an organic carbon (OC) concentration of 100 to 200 mg C L-1. A total of 5000 m(3) of humic ground water were sprinkled onto the infiltration field at an average rate of 4.25 mm h(-1). This resulted in a rise in the water table of the shallow aquifer, The organic matter concentration of the water in the shallow aquifer, however, remained below 2.7 mg C L-1. The organic matter concentration of the pore water in the unsaturated zone was measured at the end of the experiment. The organic matter concentration of the pore water decreased from 105 mg C L-1 at 0.5 m to 20 mg C L (1) at 2.5 m under the infiltration field indicating that the soil removed the organic matter from the humic ground water, From these results we conclude that artificial recharge is a possible method for humic ground water treatment. KeyWords Plus: ORGANIC-CARBON; SUBSTANCES; REMOVAL Addresses: Gron C (reprint author), DHI Water & Environm, Agern Alle 11, Horsholm, DK-2970 Denmark DHI Water & Environm, Horsholm, DK-2970 Denmark Tech Univ Denmark, Dept Geol & Geotech Engn, Lyngby, DK-2800 Denmark Title: Origin and structures of groundwater humic substances from three Danish aquifers Author(s): Gron C, Wassenaar L, Krog M Source: ENVIRONMENT INTERNATIONAL 22 (5): 519-534 1996 Document Type: Article Language: English Cited References: 65 Times Cited: 17 Abstract: Structural, chemical, and isotopic parameters were used to identify the origins of groundwater humic substances from three Danish aquifers. A variety of analytical techniques (visible light absorption, molecular weight distribution, C-13-NMR spectroscopy, elemental composition with major elements and halogens, hydrolyzable amino acids and carbohydrates, carbon isotopes) applied to aquatic humic and fulvic acids led to consistent structural interpretations for each of the three aquifers studied. For humic substances in two-aquifers, the analyses suggested source rocks in agreement with geological and hydrogeochemical information. In a third aquifer, source rock identification was inconclusive, and multiple fossil and recent organic carbon sources are suggested. KeyWords Plus: ISOTOPIC COMPOSITION; MARINE-ENVIRONMENT; SULFUR ENRICHMENT; EARLY DIAGENESIS; C-13 NMR; ACIDS; SEDIMENTS; RATIOS; CARBON; WATERS

Title: Reactivity of organic matter in aquifer sediments: Geological and geochemical controls Author(s): Hartog N, Van Bergen PF, De Leeuw JW, Griffioen J Source: GEOCHIMICA ET COSMOCHIMICA ACTA 68 (6): 1281-1292 MAR 2004 Document Type: Article Language: English Cited References: 96 Times Cited: 3 Abstract: Reduction rates in aquifers are commonly carbon limited, but little is known about the molecular composition and degradability of sedimentary organic matter (SOM) in aquifer sediments. The composition, source and degradation status of SOM in aquifer sediments of fluvio-glacial (Pleistocene) and shallow marine (Pliocene) origin, were determined using flash pyrolysis-gas chromatography/mass spectrometry. Incubation experiments (106 d) were used to assess the reactivity of SOM towards molecular oxygen. A dominance of lignin-derived components and long chain odd-over-even predominant alkanes indicate that terrestrial higher land plants were the main source of SOM even in the shallow marine sediments, while bacterial lipid-derived hopanoids and iso- and anteiso-C-15 and C-17 fatty acids indicate a minor contribution of microbial biomass. No compositional difference was observed between SOM present in the fine (<63 mum) and coarse fraction (63-2000 mum). A significant part of SOM was not present as low-molecular-weight compounds but was macromolecularly bound. For the fluvio-glacial sediments, a relatively higher abundance of resistant macromolecular compounds was in agreement with stronger signs of aerobic lignin, alkane and hopanoid oxidation. The more degraded status of SOM in the fluvio-glacial sediments was consistent with their significantly lower SOM mineralization (2-6%) during incubation, as compared with the shallow marine sediments (9-14%). The reactivity towards oxygen of SOM was controlled by the extent of past aerobic oxidation. Not the age of SOM, but the extent of oxygen exposure during syn- and postdepositional conditions seems most important in affecting the degradation status of SOM in aquifer sediments and thus their ability to reduce oxidants. Copyright (C) 2004 Elsevier Ltd. KeyWords Plus: CHROMATOGRAPHY-MASS-SPECTROMETRY; PARTICLE-SIZE FRACTIONS; GROUNDWATER HUMIC SUBSTANCES; CONTINENTAL-MARGIN SEDIMENTS; STRAIGHT-CHAIN BIOPOLYMERS; MARINE-SEDIMENTS; ANALYTICAL PYROLYSIS; SELECTIVE PRESERVATION; PHENANTHRENE SORPTION; CARBON PRESERVATION Addresses: Hartog N (reprint author), Univ Waterloo, Dept Earth Sci, Waterloo, ON N2L 3G1 Canada Univ Utrecht, Dept Geochem, Fac Earth Sci, Utrecht, NL-3508 TA Netherlands TNO, Netherlands Inst Appl Geosci, Delft, NL-2600 Netherlands

Title: Depositional and paleohydrogeological controls on the distribution of organic matter and other reactive reductants in aquifer sediments Author(s): Hartog N, Griffioen J, van Bergen PF Source: CHEMICAL GEOLOGY 216 (1-2): 113-131 MAR 15 2005 Document Type: Article Language: English Cited References: 94 Times Cited: 0 Abstract: The reactivity of sedimentary reductants is the main control for the natural attenuation of common groundwater contaminants, such as nitrate or chlorinated hydrocarbons. Middle Miocene to Late Pleistocene (0.01-20 My old) aquifer sands of marine, fluvial, fluvio-glacial and aeolian origin were characterized to determine the control of sediment depositional environment, sediment age and paleohydrology on the distribution and reactivity of sedimentary reductants. In addition to the variability in the molecular composition of sedimentary organic matter (SOM), the reduction reactivity of these sediments was determined. Oxygen consumption and carbon dioxide production during sediment incubations indicated that SOM, pyrite and ferrous iron-bearing carbonates were the main reductants. Bulk delta(13)C(org)-values (similar to 25 parts per thousand) indicated that terrestrial higher land plants were the main precursor of SOM, regardless of sediment origin. However, pyrolysis-GC/MS analysis showed that SOM in the marine Tertiary sands contained lignin with preserved side-chains, while in the Pleistocene fluvial and fluvio-aeolian sediments, highly degraded lignin and recalcitrant macromolecular aliphatic structures dominated SOM, indicative of aerobic degradation. The higher dynamics of these terrestrial depositional environments as compared with their marine counterpart, likely allows for increased oxygen exposure times and thus more intense aerobic degradation of SOM. The aquifer sediment that fills a large erosional valley created during the Saale ice-age, likely consists of fluvio-glacially reworked marine Tertiary sediments, as supported by carbonate isotopic evidence. The more degraded status and decreased reactivity of SOM in this sediment than in its precursor, is likely due to the increased oxygen exposure during dynamic fluvio-glacial reworking. Despite the highly degraded nature of SOM and the absence of pyrite in the Pleistocene fluvial and fluvio-aeolian sediments, oxygen consumption rates were high during the incubation of sediments from the shallowest part of the aquifer. A reactive ferroan carbonate phase was inferred as the main source of oxidant demand in shallow fluvial and aeolian sands. Depleted oxygen and carbon isotopes indicated that this phase was groundwater derived. Aerobic degradation during sediment deposition appears to control the molecular composition and reactivity of SOM in aquifer sediments and to affect the potential of subsequent diagenetic pyrite formation. In addition, (paleo)hydrological conditions may result in the accumulation of a ferrous iron-bearing carbonate phase precipitated during the exfiltration of Fe(II)containing anoxic groundwater. (c) 2004 Elsevier B.V All rights reserved. Author Keywords: kerogen; sedimentary organic matter; pyrite; ferrous iron; oxygen reduction; pyrolysis; carbonate isotopes KeyWords Plus: ATLANTIC COASTAL-PLAIN; CHROMATOGRAPHY-MASS- SPECTROMETRY; CARBONATE-BUFFERED SOLUTION; ANALYTICAL PYROLYSIS; CHEMICAL-COMPOSITION; NITRATE REDUCTION; SULFATE REDUCTION; MARINE- SEDIMENTS; PYRITE OXIDATION; SWAMP SEDIMENTS

Title: Dissolved organic carbon transformations during laboratory-scale groundwater recharge using lagoon-treated wastewater Author(s): Westerhoff P, Pinney M Source: WASTE MANAGEMENT 20 (1): 75-83 2000 Document Type: Article Language: English Cited References: 21 Times Cited: 4 Abstract: Reuse of treated wastewater through groundwater recharge has emerged as an integral part of water and wastewater management in arid regions of the world, Aerated-lagoon wastewater treatment followed by surface infiltration offers a simple low- tech, low-cost treatment option for developing countries. This study investigated the fate of dissolved organic carbon (DOC) through laboratory-scale soil aquifer treatment (SAT) soil columns over a 64-week period. Aerated-lagoon wastewater (average DOC = 17 mg/l) and two soils were collected near the USA/Mexico border near Nogales, AZ. Laboratory-scale SAT columns exhibited three phases of 'aging' where infiltration rates and DOC removals were delineated. DOC removal ranged from 39% to greater than 70% during the study, with DOC levels averaging 3.7 and 5.8 mg/l for the SAT columns packed with different soils. Soil with a higher fraction of organic carbon content had higher effluent DOC levels, presumably due to leaching of soil organic matter. UV absorbance data indicated preferential biodegradation removal of low molecular weight, low aromatic DOC. Overall, SAT, reduced the potential towards forming trihalomethanes (THMs) during disinfection, although the reactivity (mu g THM/mg DOC) increased. SAT and groundwater recharge would provide a high degree of DOC removal in an integrated low-tech wastewater reuse management strategy, especially for developing countries in arid regions of the world. (C) 2000 Elsevier Science Ltd. All rights reserved. Author Keywords: dissolved organic carbon; aerated lagoon; groundwater recharge KeyWords Plus: SOIL AQUIFER TREATMENT; WATER; INFILTRATION Addresses: Westerhoff P (reprint author), Arizona State Univ, Dept Civil & Environm Engn, Box 5306,Engn Ctr Room ECG252, Tempe, AZ 85287 USA Arizona State Univ, Dept Civil & Environm Engn, Tempe, AZ 85287 USA Burgess & Niple Inc, Project Engn, Phoenix, AZ 85034 USA

Title: Nature and transformation of dissolved organic matter in treatment wetlands Author(s): Barber LB, Leenheer JA, Noyes TI, Stiles EA Source: ENVIRONMENTAL SCIENCE & TECHNOLOGY 35 (24): 4805-4816 DEC 15 2001 Document Type: Article Language: English Cited References: 39 Times Cited: 10 Abstract: This investigation into the occurrence, character, and transformation of dissolved organic matter(DOM) in treatment wetlands in the western United States shows that (i) the nature of DOM in the source water has a major influence on transformations that occur during treatment, (ii) the climate factors have a secondary effect on transformations, (ii!) the wetlands receiving treated wastewater can produce a not increase in DOM, and (iv) the hierarchical analytical approach used in this study can measure the subtle DOM transformations that occur. As wastewater treatment plant effluent passes through treatment wetlands, the DOM undergoes transformation to become more aromatic and oxygenated. Autochthonous sources are contributed to the DOM, the nature of which is governed by the developmental stage of the wetland system as well as vegetation patterns. Concentrations of specific waste water derived organic contaminants such as linear alkylbenzene sulfonate, caffeine, and ethylenediaminotetraacetic acid were significantly attenuated by wetland treatment and were not contributed by internal loading. KeyWords Plus: CONSTRUCTED WETLANDS; GAS-CHROMATOGRAPHY; MOLECULAR- WEIGHT; HUMIC SUBSTANCES; WASTE-WATER; WASTEWATERS; CALIFORNIA; EFFLUENTS; REMOVAL; CARBON Addresses: Barber LB (reprint author), US Geol Survey, 3215 Marine St, Boulder, CO 80303 USA US Geol Survey, Boulder, CO 80303 USA US Geol Survey, Denver, CO 80225 USA US Bur Reclamat, Denver, CO 80225 USA

Title: Assessing the removal potential of soil-aquifer treatment systems for bulk organic matter Author(s): Rauch T, Drewes L Source: WATER SCIENCE AND TECHNOLOGY 50 (2): 245-253 2004 Document Type: Review Language: English Cited References: 16 Times Cited: 2 Abstract: The fate of effluent organic matter (EfOM) during groundwater recharge was investigated by studying the removal behavior of four bulk organic carbon fractions isolated from a secondary effluent: Hydrophilic organic matter (HPI), hydrophobic acids (HPO-A), colloidal organic matter (OM), and soluble microbial products (SMPs). Short- term removal of the bulk organic fractions during soil infiltration was simulated in biologically active soil columns. Results revealed that the four organic fractions showed a significantly different behavior with respect to biological removal. HPI and colloidal OM were prone to biological removal during initial soil infiltration (0-30 cm) and supported soil microbial biomass growth in the infiltrative surface. Additionally, colloidal OM was partly removed by physical adsorption or filtration. HPO-A and SMPs reacted recalcitrant towards biological degradation as indicated by low soil biomass activity responses. Adsorbability assessment of the biologically refractory portions of the fractions onto powered activated carbon (PAC) indicated that physical removal is not likely to play a significantly role in further diminishing recalcitrant HPO-A, HPI and SMPs during longer travel times in the subsurface. Author Keywords: colloidal organic matter; effluent organic matter; hydrophilic organic matter; hydrophobic acids; soluble microbial products; water reuse KeyWords Plus: RECLAIMED WATER; DRINKING-WATER; GROUNDWATER; NOM Addresses: Rauch T (reprint author), Colorado Sch Mines, Div Environm Sci & Engn, Golden, CO 80401 USA Colorado Sch Mines, Div Environm Sci & Engn, Golden, CO 80401 USA E-mail Addresses: [email protected], [email protected]

Title: Removal of organic matter and nitrogen from river water in a model floodplain Author(s): Chung JB, Kim SH, Jeong BR, Lee YD Source: JOURNAL OF ENVIRONMENTAL QUALITY 33 (3): 1017-1023 MAY-JUN 2004 Document Type: Article Language: English Cited References: 26 Times Cited: 1 Abstract: A significant improvement in river water quality cannot be expected unless nonpoint-source contaminants are treated in addition to the further treatment of point- source contaminants. If river water is sprayed over a floodplain, the consequent water filtration through the sediment profile can simultaneously remove organic matter and nitrogen in the water through aerobic and denitrifying reactions. This hypothesis was tested using lysimeters constructed from polyvinyl chloride (PVC) pipe (150 cm long, 15 cm in diameter) packed with loamy sand floodplain sediment. Water was applied to the top of the lysimeters at three different flow rates (48, 54, and 68 mm d(-1)). Concentrations of NO3 and dissolved oxygen (DO), chemical oxygen demand (COD), and redox potential (Eh) in the water were measured as functions of depth after the system reached steady states for both water flow and reactions. At the rate of 68.0 mm d(-1), a reducing condition for denitrification developed below the 5-cm depth due to the depletion of 02 by organic matter degradation in the surface oxidizing layer; Eh and DO were below 205 mV and 0.4 mg L-1, respectively. At a depth of 70 cm, COD and NO3-N concentration decreased to 5.2 and 3.8 mg L-1 from the respective influent concentrations of 17.1 and 6.2 mg L-1. Most biodegradable organic matter was removed during flow and further removal of NO3 was limited by the lack of an electron donor (i.e., organic matter). These results indicate that the floodplain filtration technique has great promise for treatment of contaminated river water. KeyWords Plus: NITRATE DEPLETION; DENITRIFICATION; AQUIFER; INFILTRATION; GROUNDWATER; SOIL; SWITZERLAND; TRANSPORT; EXCHANGE; OXYGEN Addresses: Chung JB (reprint author), Daegu Univ, Dept Agr Chem, Gyongsan, 712714 South Korea Daegu Univ, Dept Agr Chem, Gyongsan, 712714 South Korea Daegu Univ, Dept Agron, Gyongsan, 712714 South Korea Yeungnam Univ, Dept Environm Engn, Kyongsan, 712749 South Korea E-mail Addresses: [email protected]

Title: Behaviour of different molecular-weight fractions of DOC of Elbe river water during river bank infiltration Author(s): Ludwig U, Grischek T, Nestler W, Neumann V Source: ACTA HYDROCHIMICA ET HYDROBIOLOGICA 25 (3): 145-150 MAY 1997 Document Type: Article Language: English Cited References: 15 Times Cited: 6 Abstract: This paper reports changes in dissolved organic carbon concentration beta(DOC) and the relation between UV-active and non-UV-active components determined for Elbe river water and river bank infiltrate in the Torgau river basin between 1992 and 1993. Using an ultrafiltration method, the fractionation of the DOC content was obtained for the fractions >10 000 g/mol, 1 000...10 000 g/mol, and <1 000 g/mol. The spectral absorption coefficient at 254 nm a(254) Of the molecular-weight fractions was also measured. The mean total DOC concentration of Elbe river water decreased from 6.0 mg/L to below 3.9 mg/L along two investigated flowpaths. Two thirds of the decrease occurred within the first few metres of the river bed and one third along the 350 m length of the groundwater flowpaths. The a(254) values showed a significant decrease from 14.8 1/m in Elbe river water to 7.8 1/m in the aquifer. Along a flowpath, the proportion of low- molecular weight fraction of DOC increased, the proportion of high-molecular weight fraction decreased, and the proportion of the 1 000...10 000 g/mol molecular-weight fraction remained relatively stable. The Elbe river water contained the main portion of UV-active compounds in the fraction 1 000...10 000 g/mol, and this was also the case for samples of river infiltrate. For the high-molecular weight fraction, mainly non-W-active compounds were attenuated in the river bed sediment. Author Keywords: DOC molecular-weight fractions; spectral absorption coefficient; river bank infiltration; ultrafiltration KeyWords Plus: TRANSPORT Addresses: Ludwig U (reprint author), Hsch Tech & Wirtsch, LB Wasserwesen, Dresden, D-01069 Germany Hsch Tech & Wirtsch, LB Wasserwesen, Dresden, D-01069 Germany Publisher: WILEY-V C H VERLAG GMBH, MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY Subject Category: ENVIRONMENTAL SCIENCES; MARINE & FRESHWATER BIOLOGY; WATER RESOURCES IDS Number: 185QP ISSN: 0323-4320

Title: Influence of humic substance alteration during soil passage on their treatment behaviour Author(s): Gerlach M, Gimbel R Source: WATER SCIENCE AND TECHNOLOGY 40 (9): 231-239 1999 Document Type: Article Language: English Cited References: 22 Times Cited: 1 Abstract: Humic substances are nor major objectives of water treatment in drinking water supply. But, as they often influence the treatment efficiency or participate in treatment reactions, their behaviour in the treatment process can significantly determine the process design. A very effective pretreatment step can be achieved by soil passage (e. g. bank filtration or slow sand filtration) which is usually involved in German surface water treatment processes. In this study transport phenomena of humic matter during underground passage are investigated with special attention to the alteration of their treatment behaviour. In a fundamental a work the deposition of humic substances was studied in a model system. Transport phenomena could mathematically be described by a filtration theory of colloidal transport. From the results of these calculations the collision efficiencies of humic substances on clean and coated surfaces can be derived. The humic substance deposition on subsurfaces is accompanied by a classification based on molecular weight. An additional alteration of dissolved humic matter due to microbiological degradation and partial resolvation of deposited humic matter was observed by passage of river water through columns containing actual soil. The alteration of dissolved organic matter during soil passage is finally characterized by its adsorption and chlorination precursor behaviour. All results confirm that bank filtration is an effective pretreatment step particulary due to the decrease in connection with improvement in treatability of humic matter. (C) 1999 Published by Elsevier Science Ltd on behalf of the IAWQ. An rights reserved. Author Keywords: humic substances; dissolved organic matter; bank filtration; adsorption; THM precursor KeyWords Plus: DEPOSITION Addresses: Gerlach M (reprint author), IWW Rhein Westfael Inst Wasserforsch, Moritzstr 26, Mulheim An Der Ruhr, D-45476 Germany IWW Rhein Westfael Inst Wasserforsch, Mulheim An Der Ruhr, D-45476 Germany Univ Duisburg Gesamthsch, Fac Mech Engn, Inst Chem Engn Water Engn, Duisburg, D- 47048 Germany Publisher: PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND Subject Category: ENGINEERING, ENVIRONMENTAL; ENVIRONMENTAL SCIENCES; WATER RESOURCES IDS Number: 264GU ISSN: 0273-1223

Title: EFFECT OF DISSOLVED ORGANIC-MATTER AND PH ON THE MIGRATION OF ZINC THROUGH RIVER BANK SEDIMENTS Author(s): BOURG ACM, DARMENDRAIL D Source: ENVIRONMENTAL TECHNOLOGY 13 (7): 695-700 JUL 1992 Document Type: Article Language: English Cited References: 7 Times Cited: 7 Abstract: The migration of zinc through river bank sediments is studied in column experiments. Even when the initial dissolved zinc is low enough to prevent precipitation of zinc minerals in the column, adsorption processes strongly retard the transport of the metal with respect to water. Organic matter, when dissolved, can significantly increase the mobility of Zn. Small pH variations are as important as organic matter in the control of the solubility and transport of zinc. The adsorption of zinc seems to control, at least partially, the solubility of organic matter (most likely as ternary surface complexes of the form solid-Zn-organics). Dissolved organic matter and pH are therefore master variables for the understanding of zinc transport through river bank sediments. Author Keywords: ZINC; DISSOLVED ORGANIC MATTER; PH; SEDIMENTS; PERCOLATION Addresses: BOURG ACM (reprint author), BUR RECH GEOL & MINIERES, NATL GEOL SURVEY, DEPT GEOCHEM, BP 6009, ORLEANS, F-45060 2 FRANCE BUR RECH GEOL & MINIERES, NORD PAS CALAIS REG AGCY, HELEMMES LILLE, F-59260 FRANCE Publisher: SELPER LTD, PUBLICATIONS DIV, 79 RUSTHALL AVENUE, LONDON, ENGLAND W4 1BN Subject Category: ENVIRONMENTAL SCIENCES IDS Number: JL029 ISSN: 0959-3330

Title: Mobilization of heavy metals and arsenic in polluted wetland soils and its dependence on dissolved organic matter Author(s): Kalbitz K, Wennrich R Source: SCIENCE OF THE TOTAL ENVIRONMENT 209 (1): 27-39 JAN 8 1998 Document Type: Article Language: English Cited References: 38 Times Cited: 48 Abstract: The wetland soils of the Mulde river in the industrial district of Bitterfeld- Wolfen (Germany) are highly contaminated with heavy metals and arsenic. We studied the mobility of accumulated heavy metals and arsenic and the influence of dissolved organic matter (DOM) on element mobility. Undisturbed soil cores were taken from five different sites to represent a wide range of heavy-metal contamination, soil properties and dissolved organic carbon (DOG) concentrations. The acid-soluble concentrations (mostly equal to the total content) were up to 1100 mg kg(-1) for Zn, 800 mg kg(-1) for Cr, 364 mg kg(-1) for Cu, 265 mg kg(-1) for As and 37 mg kg(-1) for Hg, depending on the sampling site. Percolation experiments using small lysimeters with undisturbed topsoil cores illustrated a considerable mobilization of Zn, Cd, Cu, Cr and Hg, depending on soil properties. Up to 80 mu g 1(-1) Cd, 8 mg 1(-1) Zn, 130 mu g 1(-1) Cr, 160 mu g 1(-1) Cu and 7 mu g 1(-1) Hg were detected in the soil percolates. Arsenic mobilization was low. The concentration of Cr, Hg, Cu and As in the soil percolates was positively correlated with DOM. Besides the element content (mobile or acid-soluble), soil pH and soil characteristics describing the soil potential for heavy-metal adsorption (clay, oxides, cation exchange capacity), the DOC concentration in the soil solution should be known to access the potential mobilization of Hg, Cr, Cu and As. In contrast, Cd and Zn mobilization depends on soil pH and mobile element content, but not on DOM. Additional studies on two soil profiles (down to 1.5 m) confirmed the translocation of heavy metals from the highly contaminated topsoil into deeper soil horizons and into the groundwater and the influence of DOM as revealed with the percolation experiment. Our results also showed that DOM is of minor importance on the mobilization of heavy metals in soils with a low soil pH (< 4.5). (C) 1998 Elsevier Science B.V. Author Keywords: heavy metals; arsenic; mobilization; wetland soils; percolation experiment; dissolved organic matter KeyWords Plus: SOLUBLE ORGANICS; SPECIATION; TRANSPORT; CADMIUM; COPPER; ZINC; CHEMISTRY; CARBON; SLUDGE; PINE Addresses: Kalbitz K (reprint author), Ctr Environm Res, Dept Soil Sci, Hallesche Str 44, Lauchstadt, D-06246 Germany Ctr Environm Res, Dept Soil Sci, Lauchstadt, D-06246 Germany Ctr Environm Res, Dept Analyt Chem, Leipzig, D-04318 Germany E-mail Addresses: [email protected]

Title: Complexation between Hg(II) and dissolved organic matter in stream waters: an application of fluorescence spectroscopy Author(s): Wu FC, Cai YR, Evans D, Dillon P Source: BIOGEOCHEMISTRY 71 (3): 339-351 DEC 2004 Document Type: Article Language: English Cited References: 31 Times Cited: 0 Abstract: Complexation between Hg(II) and dissolved organic matter (DOM) collected from streams in Ontario, Canada, was studied using three-dimensional excitation emission matrix (3DEEM) fluorescence spectroscopy. The results show that DOM reacted with Hg(II) rapidly, and the complexation reached pseudo-equilibrium within 20 s. Maximum excitation/emission (Ex/Em) wavelengths shifted towards the longer wavelengths, indicating that DOM structure changed during its interaction with Hg(II). Using fluorescence quenching titrations, complexing parameters, conditional stability constants and the percentage of fluorophores participating in the complexation, were estimated by the modified Stern-Volmer equation. The experimental and field survey results suggest that the Hg-DOM complexation in various streams was related to water quality parameters, e.g. DOC, Cl-, and cation concentrations, and was strongly affected by UV irradiation. Author Keywords: complexation; dissolved organic matter; fluorescence; mercury; kinetics; streams KeyWords Plus: FULVIC-ACID; HUMIC SUBSTANCES; METAL-IONS; LAKE BIWA; COPPER(II); LIGANDS; MERCURY; CARBON; FRACTIONATION; PHOSPHORUS Addresses: Wu FC (reprint author), Chinese Acad Sci, Inst Geochem, State Key Lab Environm Geochem, Guiyang, 550002 Peoples R China Chinese Acad Sci, Inst Geochem, State Key Lab Environm Geochem, Guiyang, 550002 Peoples R China Trent Univ, Dept Chem, Environm & Resource Studies Program, Peterborough, ON K9J 7B8 Canada E-mail Addresses: [email protected] Publisher: SPRINGER, VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS

Title: High-performance liquid chromatographic fractionation and characterization of fulvic acid Author(s): Wu FC, Evans RD, Dillon PJ Source: ANALYTICA CHIMICA ACTA 464 (1): 47-55 JUL 29 2002 Document Type: Article Language: English Cited References: 35 Times Cited: 6 Abstract: High-performance immobilized metal ion affinity chromatography (HP-IMAC) was used to fractionate humic substances (HS) based on their affinity for the immobilized copper(II) ion using acidic and glycine eluents. The work was carried out with two naturally occurring aqueous fulvic acids and commercially available Suwannee River fulvic acid. The IMAC-fractionated HS were then characterized by reversed-phase high- performance liquid chromatography (RP-HPLC) and size exclusion chromatography. The results showed that the affinity HS fraction eluted first using an acidic pH = 2 eluent exhibited a relatively high hydrophilic character, whereas the fraction eluted later using a glycine eluent exhibited both a higher hydrophobic character and larger molecular size. On the other hand, the HS fraction with no affinity for the immobilized copper had low molecular size. The affinity of the HS fraction for copper(II) increased with increasing molecular weight. Based on the composite results of three different HS, it is evident that strong relationships exist between affinity, molecular weight, and hydrophilic/hydrophobic properties during the HP-IMAC fractionation. The results presented here have significance for understanding the nature of chemical interactions at the molecular level between dissolved organic matter and trace metals. IMAC, coupled with other liquid chromatographic strategies, is a promising tool for chemical fractionation and characterization of HS. circle * 2002 Elsevier Science B.V. All rights reserved. Author Keywords: HPLC; immobilized metal ion affinity chromatography (IMAC); humic substances; affinity KeyWords Plus: MOLECULAR-WEIGHT FRACTIONS; AQUATIC HUMIC SUBSTANCES; ION AFFINITY-CHROMATOGRAPHY; CAPILLARY ELECTROPHORESIS; SPECTROSCOPIC PROPERTIES; ORGANIC-LIGANDS; BINDING; COPPER; COMPLEXATION; FLUORESCENCE Addresses: Wu FC (reprint author), Trent Univ, Environm & Resource Studies Program, 1600 W Bank Dr, Peterborough, ON K9J 7B8 Canada Trent Univ, Environm & Resource Studies Program, Peterborough, ON K9J 7B8 Canada Trent Univ, Dept Chem, Peterborough, ON K9J 7B8 Canada Publisher: ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS Subject Category: CHEMISTRY, ANALYTICAL

Title: HUMUS TRANSFORMATION AT THE BANK FILTRATION WATER-PLANT Author(s): MIETTINEN IT, MARTIKAINEN PJ, VARTIAINEN T Source: WATER SCIENCE AND TECHNOLOGY 30 (10): 179-187 1994 Document Type: Article Language: English Cited References: 20 Times Cited: 12 Abstract: Transformations in the amount and quality of organic matter (humus) during bank filtration of surface water were studied by analyzing the changes in total organic carbon (TOC), non-purgeable organic carbon (NPOC), chemical oxygen demand (GOD), color of water, and UV absorbing humus fractions. The amount of organic matter expressed as TOC, NPOC, and COD depended on temperature and filtration distance from lake water. The color of water and the UV absorbing humus peaks presenting different humus molecule fractions decreased more effectively than other parameters measuring the amount of organic matter in water. The ratio of COD to TOC decreased when the filtration distance of water increased. Our observations indicated that bank filtration of humus-rich lake water changed more the quality of organic matter than its total amount. Author Keywords: BANK FILTRATION; HUMUS; ORGANIC MATTER; TRANSFORMATION KeyWords Plus: DRINKING WATERS; ORGANIC-MATTER; CHROMATOGRAPHY Addresses: MIETTINEN IT (reprint author), NATL PUBL HLTH INST, DEPT ENVIRONM MICROBIOL, POB 95, KUOPIO, SF-70701 FINLAND NATL PUBL HLTH INST, DEPT ENVIRONM HYG, KUOPIO, SF-70701 FINLAND Publisher: PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB Subject Category: ENGINEERING, ENVIRONMENTAL; ENVIRONMENTAL SCIENCES; WATER RESOURCES IDS Number: QP631 ISSN: 0273-1223

Title: Molecular size fractions of treated aquatic humus Author(s): Myllykangas T, Nissinen TK, Rantakokko P, Martikainen PJ, Vartiainen T Source: WATER RESEARCH 36 (12): 3045-3053 JUL 2002 Document Type: Article Language: English Cited References: 33 Times Cited: 9 Abstract: The effects of ozone, chlorine, hydrogen peroxide, and permanganate on the aquatic humic matter with different molecular size fractions and the organic acid formation in drinking water treatment were studied. Aquatic humus in lake water (LW), artificially recharged groundwater (AW), and purified artificially recharged groundwater (PW) were fractionated by high-pressure size-exclusion chromatography (HP-SEC) with UV-254 nm detection before and after oxidation, a technique which resulted generally in seven peaks. The sum of the molecular size fractions (SMSF) of the LW was reduced by 47% during the bank filtration process, and the SMSF of the AW was reduced by 55% during the process in the water treatment plant. The oxidation of the AW resulted in reductions in the range of 18-35% of the SMSF; the respective range of the PW was 15- 69%. However, the content of the total organic carbon (TOC) reduced only slightly, and a high correlation between the TOC and the SMSF (0.911) was observed in the whole material. The greatest decreases appeared in the highest-molecular-weight fractions while the low-molecular-weight fractions remained nearly unchanged. The total content of the six organic small-molecular-weight acids (sum of the organic acids, SOA) (formate, acetate, propionate, pyruvate, oxalate, and citrate) varied between 0.1-5.1% and 0.1- 9.7% of the reduced TOC in the AW and the PW, respectively. The formation of the SOA, especially of oxalate, was the greatest after hydrogen peroxide combined with ozonation (as much as I 100 mug/L), while chlorination resulted in the SOA of < 50 mug/L. (C) 2002 Elsevier Science Ltd. All rights reserved. Author Keywords: ozonation; chlorination; aquatic humus; molecular size distribution; organic acids; drinking water KeyWords Plus: NATURAL ORGANIC-MATTER; DRINKING WATERS; SPECTROSCOPIC PROPERTIES; HYDROGEN-PEROXIDE; HUMIC SUBSTANCES; BANK FILTRATION; LAKE WATER; WEIGHT; OZONE; OZONATION Addresses: Myllykangas T (reprint author), Natl Publ Hlth Inst, Div Environm Hlth, POB 95, Kuopio, FIN-70701 Finland Natl Publ Hlth Inst, Div Environm Hlth, Kuopio, FIN-70701 Finland Univ Kuopio, Dept Environm Sci, Kuopio, FIN-70211 Finland Publisher: PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND Subject Category: ENGINEERING, ENVIRONMENTAL; ENVIRONMENTAL SCIENCES; WATER RESOURCES IDS Number: 578GW

Title: SOIL AND HYDROLOGY - THEIR EFFECT ON NOM Author(s): AIKEN G, COTSARIS E Source: JOURNAL AMERICAN WATER WORKS ASSOCIATION 87 (1): 36-45 JAN 1995 Document Type: Article Language: English Cited References: 24 Times Cited: 35 Abstract: Organic matter derived from different source materials has distinctive chemical characteristics associated with those materials. Interactions among organic matter and the minerals and inorganic constituents in soil can result in the removal and fractionation of organic matter, altering the composition and reactivity of the dissolved organic carbon (DOC). Hydrologic conditions define the flow path and control the rate of transport of DOC within the system. The nature, distribution, and reactivity of organic matter in a given system is determined, to a large extent, by the strength and nature of interactions among the various components of the environment. KeyWords Plus: DISSOLVED ORGANIC-CARBON; AQUATIC HUMIC SUBSTANCES; FULVIC-ACIDS; STREAM; DYNAMICS; WATERS; MATTER Addresses: AIKEN G (reprint author), US GEOL SURVEY, DIV WATER RESOURCES, MARIN ST SCI CTR, 3215 MARINE ST, BOULDER, CO 80303 USA STATE WATER LAB, DEPT ENGN & WATER SUPPLY, SALISBURY, SA 5108 AUSTRALIA Publisher: AMER WATER WORKS ASSN, 6666 W QUINCY AVE, DENVER, CO 80235 Subject Category: ENGINEERING, CIVIL; WATER RESOURCES IDS Number: QC350 Title: Classification of dissolved organic carbon (DOC) in river systems: Influence of catchment characteristics and autochthonous processes Author(s): Sachse A, Henrion R, Gelbrecht J, Steinberg CEW Source: ORGANIC GEOCHEMISTRY 36 (6): 923-935 2005 Document Type: Article Language: English Cited References: 53 Times Cited: 0 Abstract: Dissolved organic carbon (DOC) in surface waters is influenced by natural and anthropogenic allochthonous sources in the catchment and by autochthonous production and degradation processes. An objective differentiation procedure, a principal component analysis, has been used to answer the question: Is it possible to classify different water types using only DOC-patterns, and how do seasonal variations influence such a classification? Organic compounds from various sources and river systems were analyzed by means of automated size-exclusion chromatography. Four different DOC fractions (humic substances, polysaccharides, low molecular weight acids and low weight substances) were separated on the basis of their molecular weight characteristics and quantified on the basis of their UV absorbance. Significant differences in the quality and quantity of organic compounds were found. These were related to the character of the catchment area and to autochthonous processes. It was possible to classify peat- influenced ditch waters, peat-influenced surface waters, mineral soil-influenced and anthropogenically-influenced surface waters, and waters from small and large lake-river systems. The characterization of DOC patterns combined with principal component analysis is a powerful tool for analyzing allochthonous and autochthonous DOC sources in surface waters, especially if seasonal variations are taken into account. (c) 2005 Elsevier Ltd. All rights reserved. KeyWords Plus: SURFACE-WATER; HUMIC SUBSTANCES; FULVIC-ACIDS; AMAZON RIVER; AMINO-ACIDS; MATTER; STREAM; NUTRIENT; SOIL; DYNAMICS Addresses: Sachse A (reprint author), Holstein Str 46, Berlin, D-12161 Germany Inst Freshwater Ecol & Inland Fisheries, Chem Lab, Berlin, D-12587 Germany Karl Weierstrass Inst Math, Berlin, D-1086 Germany Humboldt Univ, Berlin, D-10099 Germany E-mail Addresses: [email protected] Publisher: PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND Subject Category: GEOCHEMISTRY & GEOPHYSICS

Title: Fluctuations of dissolved organic matter in river used for drinking water and impacts on conventional treatment plant performance Author(s): Volk C, Kaplan LA, Robinson J, Johnson B, Wood L, Zhu HW, Lechevallier M Source: ENVIRONMENTAL SCIENCE & TECHNOLOGY 39 (11): 4258-4264 JUN 1 2005 Document Type: Article Language: English Cited References: 41 Times Cited: 0 Abstract: Natural organic matter (NOM) in drinking water supplies can provide precursors for disinfectant byproducts, molecules that impact taste and odors, compounds that influence the efficacy of treatment, and other compounds that are a source of energy and carbon for the regrowth of microorganisms during distribution. NOM, measured as dissolved organic carbon (DOC), was monitored daily in the White River and the Indiana-American water treatment plant over 22 months. Other parameters were either measured daily (UV-absorbance, alkalinity, color, temperature) or continuously (turbidity, pH, and discharge) and used with stepwise linear regressions to predict DOC concentrations. The predictive models were validated with monthly samples of the river water and treatment plant effluent taken over a 2-year period after the daily monitoring had ended. Biodegradable DOC (BDOC) concentrations were measured in the river water and plant effluent twice monthly for 18 months. The BDOC measurements, along with measurements of humic and carbohydrate constituents within the DOC and BDOC pools, revealed that carbohydrates were the organic fraction with the highest percent removal during treatment, followed by BDOC, humic substances, and refractory DOC. KeyWords Plus: AQUATIC HUMIC SUBSTANCES; CARBON; CATCHMENT; REMOVAL; UPLAND; STREAMWATER; EXPORT; NOM; DOC Addresses: Volk C (reprint author), Indiana Amer Water Co Inc, 1730 Sylvan Nook Dr, Richmond, IN 47374 USA Indiana Amer Water Co Inc, Richmond, IN 47374 USA Stroud Water Res Ctr, Avondale, PA 19311 USA Indiana Amer Water Co Inc, Muncie, IN 47302 USA Sievers Instruments Inc, Boulder, CO 80301 USA Amer Water Works Serv Co Inc, Voorhees, NJ 08043 USA E-mail Addresses: [email protected] Publisher: AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 USA Subject Category: ENGINEERING, ENVIRONMENTAL; ENVIRONMENTAL SCIENCES

Title: Assessing land use impacts on water quality using microbial source tracking Author(s): Long SC, Plummer JD Source: JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION 40 (6): 1433- 1448 DEC 2004 Document Type: Article Language: English Cited References: 58 Times Cited: 0 Abstract: A renewed emphasis on source water protection and watershed management has resulted from recent amendments and initiatives under the Safe Drinking Water Act and the Clean Water Act. Knowledge of the impact of land use choices on source water quality is critical for efforts to properly manage activities within a watershed. This study evaluated qualitative relationships between land use and source water quality and the quantitative impact of season and rainfall events on water quality parameters. High levels of specific conductance tended to be associated with dense residential development, while organic carbon was elevated at several forested sites. Turbidity was generally higher in more urbanized areas. Source tracking indicators were detected in samples where land use types would predict their presence. Coliform levels were statistically different at the 95 percent confidence levels for winter versus summer conditions and dry versus wet weather conditions. Other water quality parameters that varied with season were organic carbon, turbidity, dissolved oxygen, and specific conductance. These results indicate that land use management can be effective for mitigating impacts to a water body; however, year-round, comprehensive data are necessary to thoroughly evaluate the water quality at a particular site. Author Keywords: watershed management; land use management; water quality; source water protection; nonpoint source pollution; microbial source tracking; seasonal impacts; rainfall event impacts KeyWords Plus: ANIMAL FECAL POLLUTION; INDICATOR BACTERIA; ESCHERICHIA- COLI; RHODOCOCCUS-COPROPHILUS; BACTEROIDES-FRAGILIS; BACTERIOPHAGES; CONTAMINATION; SURFACE; CLASSIFICATION; IDENTIFICATION Addresses: Long SC (reprint author), Univ Massachusetts, Dept Civil & Environm Engn, 18 Marston Hall, Amherst, MA 01003 USA Univ Massachusetts, Dept Civil & Environm Engn, Amherst, MA 01003 USA Worcester Polytech Inst, Dept Civil & Environm Engn, Worcester, MA 01609 USA E-mail Addresses: [email protected]

Title: Origin of dissolved organic carbon studied by UV-vis spectroscopy Author(s): Barreto SRG, Nozaki J, Barreto WJ Source: ACTA HYDROCHIMICA ET HYDROBIOLOGICA 31 (6): 513-518 MAR 2004 Document Type: Article Language: English Cited References: 13 Times Cited: 0 Abstract: Dissolved organic carbon (DOC) distributions in water from Lake Ipe, MS, Brazil, were investigated. The samplings were performed monthly (surface, 1 m depth, and bottom) from June 1999 to June 2000. Absorbance at 285 nm and DOC concentrations in mg dm(-3), rho(DOC), were highly correlated for the three depths. 77% of the surface, 85% for 1 m and bottom samples presented a variation between 20 dm(3) g(-1) cm(-1) and 50 dm(3) g(-1) cm(-1) of A(285 nm)/rho(DOC), that characterizes the dissolved organic matter in lake water as essentially fulvic. The ratio A(254 nm)/rho(DOC) was also sensitive for fulvic matter, and an A(250 nm)/A(365 nm) = 4 ratio was characteristic of strongly colored waters. The ratios A(436 nm)/rho(DOC) for the three depths also showed a significant correlation. The predominance of fulvic acid is explained by environmental characteristics such as the tropical climate, temperatures above 18degreesC, and the lake environment. It was demonstrated that the variation in the water carbon content due to different compartments in the lake can be monitored by UV-vis spectroscopy ratios. Author Keywords: A/DOC ratio; fulvic acid; tropical lake; natural organic matter KeyWords Plus: MATTER; WATER; NOM Addresses: Barreto WJ (reprint author), Londrina State Univ, Dept Chem, Lab Environm Phys Chem, Londrina, PR BR-86051990 Brazil Londrina State Univ, Dept Chem, Lab Environm Phys Chem, Londrina, PR BR-86051990 Brazil Maringa State Univ, Grad Program Ecol Aquat & Continental Environm, Maringa, Parana BR-87020900 Brazil Maringa State Univ, Dept Chem, Maringa, Parana BR-87020900 Brazil E-mail Addresses: [email protected] Publisher: WILEY-V C H VERLAG GMBH, PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY

Title: Transformation of effluent organic matter during subsurface wetland treatment in the Sonoran Desert Author(s): Quanrud DM, Karpiscak MM, Lansey KE, Arnold RG Source: CHEMOSPHERE 54 (6): 777-788 FEB 2004 Document Type: Article Language: English Cited References: 39 Times Cited: 0 Abstract: The fate of dissolved organic matter (DOM) during subsurface wetland treatment of wastewater effluent in a hot, semi-arid environment was examined. The study objectives were to (1) discern changes in the character of dissolved organics as consequence of wetland treatment (2) establish the nature of wetland-derived organic matter, and (3) investigate the impact of wetland treatment on the formation potential of trihalomethanes (THMs). Subsurface wetland treatment produced little change in DOM polarity (hydrophobic-hydrophilic) distribution. Biodegradation of labile effluent organic matter (EfOM) and internal loading of wetland-derived natural organic matter (NOM) together produced only minor changes in the distribution of carbon moieties in hydrophobic acid (HPO-A) and transphilic acid (TPI-A) isolates of wetland effluent. Aliphatic carbon decreased as a percentage of total carbon during wetland treatment. The ratio of atomic C:N in wetland-derived NOM suggests that its character is determined by microbial activity. Formation of THMs upon chlorination of HPO-A and TPI-A isolates increased as a consequence of wetland treatment. Wetland-derived NOM was more reactive in forming THMs and less biodegradable than EfOM. For both HPO-A and TPI-A fractions, relationships between biodegradability and THM formation potential were similar among EfOM and NOM isolates; the less biodegradable isolates exhibited greater THM formation potential. (C) 2003 Elsevier Ltd. All rights reserved. Author Keywords: wetland treatment; effluent organic matter; natural organic matter; hydrophobic acid; transphilic acid; trihalomethanes KeyWords Plus: DISINFECTION BY-PRODUCTS; CONSTRUCTED WETLAND; HUMIC SUBSTANCES; WASTE-WATER; DRINKING-WATER; CARBON; ACIDS; PRECURSORS; SYSTEMS; HABITAT Addresses: Quanrud DM (reprint author), Univ Arizona, Off Arid Lands Studies, Tucson, AZ 85719 USA Univ Arizona, Off Arid Lands Studies, Tucson, AZ 85719 USA Univ Arizona, Dept Civil Engn & Engn Mech, Tucson, AZ 85721 USA Univ Arizona, Dept Environm Chem & Engn, Tucson, AZ 85721 USA Publisher: PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND Subject Category: ENVIRONMENTAL SCIENCES IDS Number: 759PA Title: DOC and DBP precursors in western US watersheds and reservoirs Author(s): Nguyen ML, Baker LA, Westerhoff P Source: JOURNAL AMERICAN WATER WORKS ASSOCIATION 94 (5): 98-112 MAY 2002 Document Type: Article Language: English Cited References: 33 Times Cited: 3 Abstract: The Horseshoe-Bartlett water supply reservoir system on the Verde River in Arizona was studied to determine the impact of hydrologic variability on dissolved organic carbon (DOC) export from the watershed and DOC production within the reservoir system. High DOC concentrations occurred during spring snowmelt and late summer monsoon rains. The majority (similar to90%) of DOC loading (kilograms per month) from the Verde River watershed occurred in the spring. Bacterial consumption and algal production of DOC changed the chemical characteristics of DOC in the reservoir. DOC loading was reduced by 21 to 38%, and haloacetic acid precursor loading was reduced by 30 to 45% as water passed through the Horseshoe-Bartlett reservoir system in 1998-99. Depending on annual hydrologic patterns and reservoir operation, the Horseshoe-Bartlett reservoir system can either produce or consume DOC. KeyWords Plus: DISSOLVED ORGANIC-CARBON; HYDROLOGY; TRANSPORT; COLORADO; ARIZONA; MODELS; LAKES; RIVER Addresses: Nguyen ML (reprint author), Arizona State Univ, Dept Civil & Environm Engn, Box 5306, Tempe, AZ 85287 USA Arizona State Univ, Dept Civil & Environm Engn, Tempe, AZ 85287 USA Publisher: AMER WATER WORKS ASSOC, 6666 W QUINCY AVE, DENVER, CO 80235 USA Subject Category: ENGINEERING, CIVIL; WATER RESOURCES IDS Number: 552MA

Title: Ion exchange for the removal of natural organic matter Author(s): Bolto B, Dixon D, Eldridge R Source: REACTIVE & FUNCTIONAL POLYMERS 60: 171-182 Sp. Iss. SI, 2004 Document Type: Article Language: English Cited References: 65 Times Cited: 0 Abstract: Because of their aliphatic and carboxylic acid structures, the polar components of natural organic matter (NOM), both charged and neutral, can give high yields of disinfection by-products (DBPs). For removal of charged organic species, ion exchange is better performing than coagulation with inorganic salts such as alum, as it very efficiently removes essentially all of the charged material, while alum preferentially removes only the larger molecules in these fractions. The influence of resin structure on performance is reviewed. There is an increase in NOM removal for quaternary ammonium resins of higher water content, with the more open structures allowing easier entry of the larger NOM species. Polar groups and the degree of crosslinking affect the water content of the resin. The environment around the nitrogen is evidently critical, with hydroxyethyl or the absence of two methyl groups on the N (as with a secondary amino group) being beneficial in NOM removal. Having a pendant OH group close to the quaternary nitrogen is a distinct advantage as the resins remove more NOM than would be expected from their water content: an appropriate balance of polar and non-polar regions in the resin structure appears to be required. Having a higher charge density than quaternary ammonium groups, protonated secondary amino sites have a greater affinity for hydrophilic counter ions. There is scope for the synthesis of improved resin systems, both strong and weak base. Thus chitosan, an amino polysaccharide, can function as a soluble cationic coagulant for NOM, as can polyethyleneimine. It is postulated that they act via hydrogen bonding, as a charge mechanism is unlikely because the polymers are only partially ionised at neutral pH. Crosslinked versions could therefore be effective in removing NOM. Crown Copyright (C) 2004 Published by Elsevier B.V. All rights reserved. Author Keywords: ion exchange; natural organic matter; adsorption; humic acids; fulvic acids KeyWords Plus: SIZE-EXCLUSION CHROMATOGRAPHY; DRINKING-WATER TREATMENT; WEAK BASE RESINS; ANION-EXCHANGE; HUMIC SUBSTANCES; AQUEOUS-SOLUTION; TRACE ORGANICS; RIVER WATER; COAGULATION; FRACTIONATION Addresses: Bolto B (reprint author), CSIRO, POB 56,, Highett, Vic 3190 Australia CSIRO, Clayton, Vic 3169 Australia Univ Melbourne, Dept Chem Engn, Parkville, Vic 3010 Australia CSIRO, Cap XX Pty Ltd, Clayton, Vic 3169 Australia E-mail Addresses: [email protected] Publisher: ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS Subject Category: CHEMISTRY, APPLIED; ENGINEERING, CHEMICAL; POLYMER SCIENCE

Title: Removal of natural organic matter by ion exchange Author(s): Bolto B, Dixon D, Eldridge R, King S, Linge K Source: WATER RESEARCH 36 (20): 5057-5065 DEC 2002 Document Type: Article Language: English Cited References: 30 Times Cited: 5 Abstract: Ion exchange is an effective method for removing humic substances from drinking water supplies. We have explored a range of anion exchangers for removal of natural organic matter (NOM), both as isolated from surface waters and after fractionation into four fractions based on hydrophobic and hydrophilic properties. Resins of open structure and high water content are confirmed as the better performers, being very efficient at removal of any charged material, especially that of smaller molecular size. Quaternary ammonium resins. containing polar groups are especially effective. The presence of a neighbouring OH group close to the quaternary nitrogen, heteroatoms in the bridge between the exchange site and the polymer backbone, a secondary amino group as the exchange site, or a low ratio of carbon to quaternary nitrogen is beneficial. A suitable balance of polar and non-polar regions in the resin structure appears to be required. Weakly basic amino groups may have a greater affinity for hydrophilic counter ions than quaternary ammonium groups, but generally there are fewer charged sites in the resin at neutral pH. Nevertheless, weak base resins have NOM uptakes nearly as high as strong base resins of similar water content. Water content was found to be the most important parameter, though the effect was less pronounced for strong base resins. For weak base resins of low charge density a non-electrostatic mechanism involving hydrogen bonding of the undissociated acidic species in the NOM to the unprotonated amino groups on the resins is proposed. Crown Copyright (C) 2002 Published by Elsevier Science Ltd. All rights reserved. Author Keywords: natural organic matter; NOM; anion exchange; humic substances; size exclusion; NOM fractions KeyWords Plus: HUMIC SUBSTANCES; WATER; COAGULATION; EXPERIENCES; RESINS Addresses: Bolto B (reprint author), CSIRO, Mol Sci, Bag 10, Clayton, Vic 3169 Australia CSIRO, Mol Sci, Clayton, Vic 3169 Australia Publisher: PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND Subject Category: ENGINEERING, ENVIRONMENTAL; ENVIRONMENTAL SCIENCES; WATER RESOURCES IDS Number: 612TL

Title: Experimental evaluation of cationic polyelectrolytes for removing natural organic matter from water Author(s): Bolto B, Abbt-Braun G, Dixon D, Eldridge R, Frimmel F, Hesse S, King S, Toifl M Source: WATER SCIENCE AND TECHNOLOGY 40 (9): 71-79 1999 Document Type: Article Language: English Cited References: 23 Times Cited: 15 Abstract: The effectiveness of water treatment processes in removing natural organic matter varies with the nature of the natural organic matter (NOM), its molecular size, polarity and charge density, and with properties of the raw water such as turbidity and hardness. In some cases conventional alum treatment is inefficient. We have compared NOM removals achieved by conventional and polymer-based processes in bench-scale treatment of reconstituted ground and surface waters of varying colour, made from NOM isolated from the same waters. NOM isolates were fractionated by adsorption on non- functionalised resins and an anion exchanger, and characterised by size exclusion chromatography. Jar tests with the isolated NOM compared coagulation with polyelectrolytes, alum clays and metal oxides, with each of the inorganics being in conjunction with a polyelectrolyte. Jar tests on reconstituted waters with alum and/or cationic polyelectrolyte show synergistic benefits from combinations of the two. The more hydrophobic NOM fractions were the most easily removed by polymer. The performance of cationic polymers improved significantly with increasing charge density and molecular weight. An alum/polymer combination is the most attractive treatment option. (C) 1999 Published by Elsevier Science Ltd on behalf of the IAWQ. All rights reserved. Author Keywords: cationic polyelectrolytes; primary coagulation; clays; metal oxides; size exclusion chromatography; alum plus polyelectrolyte KeyWords Plus: SENSITIVITY DOC-DETECTION; HUMIC SUBSTANCES; FILTRATION; COAGULATION; POLYMERS Addresses: Bolto B (reprint author), CSIRO Mol Sci, Bag 10, S Clayton, Vic 3169 Australia CSIRO Mol Sci, S Clayton, Vic 3169 Australia Univ Karlsruhe, Engler Bunte Inst Water Chem, Karlsruhe, Germany Publisher: PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND Subject Category: ENGINEERING, ENVIRONMENTAL; ENVIRONMENTAL SCIENCES; WATER RESOURCES IDS Number: 264GU

Title: Removal of humic substances by adsorption/ion exchange Author(s): Fettig J Source: WATER SCIENCE AND TECHNOLOGY 40 (9): 173-182 1999 Document Type: Article Language: English Cited References: 47 Times Cited: 13 Abstract: This paper gives an overview over the ability of four different sorbent media, activated carbon, anion exchange resins, carbonaceous resins and metal oxides, for the removal of humic sustances. Both sorbent characteristics and solution parameters that affect the ultimate capacities are discussed, and approaches developed in order to describe sorption equilibria and rate of uptake are reported. In addition, successes and failures of predictive models are described. Some general conclusions about favorable conditions for the removal of humic substances by sorption processes are given. (C) 1999 Published by Elsevier Science Ltd on behalf of the IAWQ. All rights reserved. Author Keywords: activated carbon; activated alumina; adsorption; humic substances; ion exchange; predictive models KeyWords Plus: ACTIVATED CARBON ADSORPTION; NATURAL ORGANIC-MATTER; WATER-TREATMENT; GAC; KINETICS; OXYGEN; ACIDS; TESTS Addresses: Fettig J (reprint author), Univ Gesamthsch Paderborn, Dept Environm Engn, Wilhelmshohe 44, Hoxter, D-37671 Germany Univ Gesamthsch Paderborn, Dept Environm Engn, Hoxter, D-37671 Germany Publisher: PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND Subject Category: ENGINEERING, ENVIRONMENTAL; ENVIRONMENTAL SCIENCES; WATER RESOURCES IDS Number: 264GU

Title: Characterization of natural organic matter using high performance size exclusion chromatography Author(s): Pelekani C, Newcombe G, Snoeyink VL, Hepplewhite C, Assemi S, Beckett R Source: ENVIRONMENTAL SCIENCE & TECHNOLOGY 33 (16): 2807-2813 AUG 15 1999 Document Type: Article Language: English Cited References: 32 Times Cited: 40 Abstract: High performance size exclusion chromatography (HPSEC) was used to obtain the molecular weight distributions of natural organic matter (NOM) from two South Australian drinking water sources. The NOM was separated into five nominal molecular weight fractions (<500, 500-3K, 3K-10K, 10K-30K, and >30K) using ultrafiltration membranes prior to HPSEC analysis. The use of HPSEC as a tool for NOM characterization was compared with an independent method, flow field-flow fractionation (FIFFF), which separates molecules via a different mechanism. Unlike HPSEC, which uses a porous gel with a controlled pore size distribution to separate molecules, FIFFF uses hydrodynamic and molecular diffusion principles to separate molecules on the basis of molecular size, in the absence of a porous gel. The comparison was made using the following parameters: weight-average molecular weight (M-w), number-average molecular weight (M-n), peak molecular weight (M-p), polydispersivity (M-w/M-n), and molecular weight range (80% confidence limits). Within the technical limitations of each method, good agreement was obtained between HPSEC and FIFFF for the different fractions. Although solute-gel interactions were identified with the HPSEC system, the validation of the technique with FIFFF indicates that HPSEC can provide useful and reliable molecular weight distributions of NOM in drinking water supplies. KeyWords Plus: FIELD-FLOW FRACTIONATION; MOLECULAR-WEIGHT DISTRIBUTIONS; GEL-PERMEATION CHROMATOGRAPHY; AQUATIC HUMIC SUBSTANCES; PAPER-MILL EFFLUENTS; ADSORPTION; CARBON; PULP; TOOL; MASS Addresses: Pelekani C (reprint author), Univ Illinois, Newmark Civil Engn Lab, Dept Civil & Environm Engn, 205 N Mathews Ave, Urbana, IL 61801 USA Univ Illinois, Newmark Civil Engn Lab, Dept Civil & Environm Engn, Urbana, IL 61801 USA CRC Water Qual & Treatment, Salisbury, SA 5108 Australia Monash Univ, Water Studies Ctr, CRC Freshwater Ecol, Clayton, Vic 3168 Australia Monash Univ, Dept Chem, Clayton, Vic 3168 Australia Publisher: AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 USA Subject Category: ENGINEERING, ENVIRONMENTAL; ENVIRONMENTAL SCIENCES IDS Number: 227HF

Title: Seasonal variation in molecular mass and optical properties of chromophoric dissolved organic material in coastal waters of southwest Florida Author(s): Zanardi-Lamardo E, Moore CA, Zika RG Source: MARINE CHEMISTRY 89 (1-4): 37-54 OCT 2004 Document Type: Article Language: English Cited References: 38 Times Cited: 1 Abstract: One of the most important natural sunlight absorbing substances in water is the chromophoric dissolved organic material (CDOM). Its influence on optical properties has been studied for many years, but questions of how its structural and optical characteristics change in the environment still remain. CDOM water samples were collected from coastal waters of southwest Florida during three cruises in the year 2001: one in the dry season (June) and two in the rainy season (September and November). Analyses of molecular mass (MM) distribution and optical characteristics were done using the flow field-flow fractionation (FIFFF) separation technique with absorbance and fluorescence detectors. On the basis of the results, mixing, source variability, degradation, and excited state quenching processes are important determinants of CDOM composition and optical properties in this region. During the dry season, the MM distribution did not change significantly spatially. In September and November, higher MM compounds and an increase of CDOM fluorescence were observed, found inside the rivers and in near-coastal samples, consistent with the rivers being a significant CDOM source. Results suggest that chromophores were broken down to smaller MM compounds faster than fluorophores, indicating that the fluorescent moieties are more resistant to degrading/removal processes than the non-fluorescing compounds, even though the fluorophores were always centered at lower MM. On the other hand, the fluorescence quantum yield decreased faster than absorbance coefficients, suggesting that fluorophores were quenched by complexing with some metals. For all months, the chromophores' MM for offshore samples remained the same. The carbon concentration ratio between chromophores and fluorophores changed from lower to higher salinities, suggesting that the composition of the waters changed toward offshore. The differences in the optical characteristics, MM distributions, and carbon concentration observed suggest that the CDOM sources, physical, and photochemical degradation processes change seasonally. (C) 2004 Elsevier B.V. All rights reserved. Author Keywords: molecular mass; optical properties; CDOM; flow field-flow fractionation KeyWords Plus: FIELD-FLOW FRACTIONATION; SIZE-EXCLUSION CHROMATOGRAPHY; HUMIC SUBSTANCES; NATURAL-WATERS; FULVIC-ACID; SPECTROSCOPIC PROPERTIES; COLLOIDAL MATERIAL; ORINOCO RIVER; MATTER; FLUORESCENCE Addresses: Zanardi-Lamardo E (reprint author), Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Div Marine & Atmospher Chem, 4600 Rickenbacker Causeway, Miami, FL 33149 USA Univ Miami, Rosenstiel Sch Marine & Atmospher Sci, Div Marine & Atmospher Chem, Miami, FL 33149 USA E-mail Addresses: [email protected]

Title: Molecular weight fractionation of humic substances by adsorption onto minerals Author(s): Hur J, Schlautman MA Source: JOURNAL OF COLLOID AND INTERFACE SCIENCE 264 (2): 313-321 AUG 15 2003 Document Type: Article Language: English Cited References: 43 Times Cited: 8 Abstract: Molecular weight (MW) fractionation of Suwannee River fulvic acid (SRFA) and purified Aldrich humic acid (PAHA) by adsorption onto kaolinite and hematite was investigated in equilibrium and rate experiments with a size-exclusion chromatography system using ultraviolet (UV) light detection. The extent of adsorptive fractionation based on UV detection was positively correlated with the percent carbon adsorption for both humic substances (HS), although the specific fractionation pattern observed depended on the particular HS and mineral used. Higher MW fractions of SRFA, an aquatic HS, were preferentially adsorbed to both kaolinite and hematite whereas the fractionation trends for PAHA, a terrestrial peat HS, differed for the two minerals. The contrasting fractionation patterns for SRFA versus PAHA can be explained reasonably well by the different structural trends that occur in their respective MW fractions and the underlying adsorption processes. Rate studies of adsorptive fractionation revealed an initial rapid uptake of smaller HS molecules by the mineral surfaces, followed by their replacement at the surface by a much slower uptake of the larger HS molecules present in aqueous solution. (C) 2003 Elsevier Inc. All rights reserved. Author Keywords: humic substances; adsorption; fractionation; molecular weight; size exclusion chromatography; mineral surface KeyWords Plus: NATURAL ORGANIC-MATTER; SIZE-EXCLUSION CHROMATOGRAPHY; FULVIC-ACID; AROMATIC-HYDROCARBONS; IRON-OXIDES; TRANSPORT; GOETHITE; MECHANISMS; DESORPTION; SORPTION Addresses: Schlautman MA (reprint author), Clemson Univ, Dept Agr & Biol Engn, Clemson, SC 29634 USA Clemson Univ, Dept Agr & Biol Engn, Clemson, SC 29634 USA Clemson Univ, Dept Environm Engn & Sci, Anderson, SC 29625 USA Clemson Univ, Dept Environm Toxicol, Pendleton, SC 29670 USA Clemson Univ, Clemson Inst Environm Toxicol, Pendleton, SC 29670 USA Publisher: ACADEMIC PRESS INC ELSEVIER SCIENCE, 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA Subject Category: CHEMISTRY, PHYSICAL IDS Number: 714XV

Title: Removal of NOM in the different stages of the water treatment process Author(s): Matilainen A, Lindqvist N, Korhonen S, Tuhkanen T Source: ENVIRONMENT INTERNATIONAL 28 (6): 457-465 DEC 2002 Document Type: Article Language: English Cited References: 20 Times Cited: 3 Abstract: Natural organic matter (NOM) is abundant in natural waters in Finland and in many ways affects the unit operations in water purification. in this study, the organic matter content in water in different stages of a full-scale treatment process over I year was measured. The full-scale treatment sequence, studied at the Rusko water treatment plant in Tampere, Finland, consisted of coagulation, flocculation, clarification by sedimentation or flotation, activated carbon (AC) filtration, and disinfection. High- performance size exclusion chromatography (HPSEC) was used for separation to determine changes in the humic substances content during the purification process. In addition, total organic carbon (TOC), KMnO4-number, and UV-absorbance at wavelength 254 nm (UV254) were measured. High molecular weight (HMW) matter was clearly easier to remove in coagulation and clarification than low molecular weight (LMW) matter. Furthermore, depending on the regeneration of the activated carbon filters, activated carbon filtration was effective to a degree but did not remove most of the lowest molecular weight compounds. Significant correlation was established among HPSEC, KMnO4, UV254 absorbance, and TOC. HPSEC proved to be a fast and relatively easy method to estimate NOM content in water and, in fact, gave more information than traditional methods on the type of NOM in a water sample. It also helped the process performance follow-up. (C) 2002 Elsevier Science Ltd. All rights reserved. Author Keywords: high-performance size exclusion chromatography (HPSEC); natural organic matter (NOM); drinking water; water purification KeyWords Plus: SIZE-EXCLUSION CHROMATOGRAPHY; MOLECULAR-WEIGHT DISTRIBUTION; DISSOLVED ORGANIC-MATTER; HUMIC SUBSTANCES; DRINKING WATERS; PERFORMANCE; RAW; ADSORPTION; HPSEC Addresses: Tuhkanen T (reprint author), Tampere Univ Technol, Inst Environm Engn & Biotechnol, POB 541, Tampere, FIN-33101 Finland Tampere Univ Technol, Inst Environm Engn & Biotechnol, Tampere, FIN-33101 Finland Publisher: PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND Subject Category: ENVIRONMENTAL SCIENCES

Title: Estuarine/marine UDOM as characterized by size-exclusion chromatography and organic mass spectrometry Author(s): Minor EC, Simjouw JP, Boon JJ, Kerkhoff AE, van der Horst J Source: MARINE CHEMISTRY 78 (2-3): 75-102 MAY 2002 Document Type: Article Language: English Cited References: 39 Times Cited: 3 Abstract: High performance size-exclusion chromatography (HPSEC) and direct temperature-resolved mass spectrometry (DT-MS) were used to explore molecular weight distributions and molecular level characteristics within marine/estuarine ultrafiltered dissolved organic matter (UDOM, > 1 kDa) collected from the lower Chesapeake Bay, USA and the Oosterschelde estuary, The Netherlands. Initial HPSEC characterization indicates that the overall size distribution is similar in all the UDOM samples; however, there are distinct variations among the samples, especially in the low molecular weight region. As a preliminary study of molecular level variations with apparent molecular size, the Oosterschelde UDOM sample was separated into molecular weight fractions using HPSEC. These fractions were then analyzed by DT-MS. The size fractions within the UDOM sample yielded distinctly different mass spectra; the larger size classes were enriched in ammosugars, deoxysugars, and methylated sugars while the smaller size classes were enriched in hexose sugars. There is also evidence that hexose sugars appear in at least two structures with highly different molecular weights and potentially highly different source and sink functions within the marine water column. (C) 2002 Elsevier Science B.V All rights reserved. Author Keywords: marine dissolved organic matter; ultrafiltration; size exclusion chromatography; mass spectrometry KeyWords Plus: AQUATIC HUMIC SUBSTANCES; MOLECULAR-WEIGHT; ANALYTICAL PYROLYSIS; PORE WATERS; MATTER; COLLOIDS; CARBON; ACIDS; OCEAN; ABUNDANCE Addresses: Minor EC (reprint author), Old Dominion Univ, Dept Chem & Biochem, Alfriend Chem Bldg, Norfolk, VA 23529 USA Old Dominion Univ, Dept Chem & Biochem, Norfolk, VA 23529 USA Old Dominion Univ, Dept Ocean Earth & Atmospher Sci, Norfolk, VA 23529 USA AMOLF, FOM Inst, Amsterdam, NL-1098 SJ Netherlands Publisher: ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS Subject Category: CHEMISTRY, MULTIDISCIPLINARY; OCEANOGRAPHY IDS Number: 560MU

Title: The molecular size of natural organic matter (NOM) determined by diffusivimetry and seven other methods Author(s): Egeberg PK, Christy AA, Eikenes M Source: WATER RESEARCH 36 (4): 925-932 FEB 2002 Document Type: Article Language: English Cited References: 22 Times Cited: 8 Abstract: The objectives of this work are to (1) determine the diffusion coefficients of natural organic matter (NOM) by diffusivimetry, (2) compare the results with diffusion coefficients determined by two other methods (fluorescence correlation spectroscopy (FCS) and dynamic adsorption experiments (DAM), (3) compare molecular weights derived from the diffusion coefficients to molecular weights determined by three different ultrafiltration experiments and high perfomance size exclusion chromatography (HPSEC). The diffusion coefficients determined in this work (stirred diffusion cell) are about 70% higher than that determined by DAM, and agree well with diffusion coefficients determined by FCS. Molecular weights determined by HPSEC are of the same magnitude as molecular weights derived from diffusion coefficients. Molecular weights determined by ultrafiltration vary considerably depending on the choice of membrane types. Membranes made of cellulose acetate generate results similar to results derived from diffusion coefficients. Membranes made of regenerated cellulose and polyether sulfone appear to retain too much of NOM, resulting in artificially high molecular weights. (C) 2002 Elsevier Science Ltd. All rights reserved. Author Keywords: NOM; diffusion coefficients; molecular weight; ultrafiltration; fluorescence correlation spectroscopy KeyWords Plus: NORWEGIAN AQUATIC NOM; SURFACE WATERS; DISTRIBUTIONS; WEIGHT Addresses: Egeberg PK (reprint author), Agder Univ Coll, Dept Nat Sci, Tordenskjolsgate 65,Servicebox 422, Kristiansand, N-4604 Norway Agder Univ Coll, Dept Nat Sci, Kristiansand, N-4604 Norway Norwegian Forest Res Inst, As, N-1432 Norway Publisher: PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND Subject Category: ENGINEERING, ENVIRONMENTAL; ENVIRONMENTAL SCIENCES; WATER RESOURCES IDS Number: 518QX

Title: Molecular size distribution of natural organic matter in raw and drinking waters Author(s): Nissinen TK, Miettinen IT, Martikainen PJ, Vartiainen T Source: CHEMOSPHERE 45 (6-7): 865-873 NOV 2001 Document Type: Article Language: English Cited References: 41 Times Cited: 11 Abstract: The purpose of this study was to compare the molecular size distribution (MSD) of natural organic matter (NOM) in raw waters (RW) and drinking waters (DW), and to find out the differences between MSD after different water treatment processes. The MSD of NOM of 34 RW and DW of Finnish waterworks were determined with high- performance size-exclusion chromatography (HPSEC). Six distinct fractions were generally separated from water samples with the TSK G3000SW column, using sodium acetate at pH 7 as an eluent. Large and intermediate humic fractions were the most dominant fractions in surface waters (lakes and rivers), while in artificially recharged groundwaters and natural groundwaters intermediate and small fractions predominated. Water treatment processes removed the two largest fractions almost completely shifting the MSD towards smaller molecular size in DW. Granular activated carbon (GAC) filtration, ozonation, and their combination reduced all humic fractions compared to the conventional treatment. Humic fractions correlated with total organic carbon (TOC) content and chemical oxygen demand, this being especially true in RW. The results demonstrate that the HPSEC method can be applied for a qualitative and also for rough estimate quantitative analyzes of NOM directly from RW and DW samples without sample pretreatment. (C) 2001 Elsevier Science Ltd. All rights reserved. Author Keywords: drinking water (DW); high-performance size-exclusion chromatography (HPSEC); humic fractions; natural organic matter (NOM); TSK column KeyWords Plus: AQUATIC HUMIC SUBSTANCES; EXCLUSION CHROMATOGRAPHY; ACTIVATED CARBON; THM PRECURSORS; REMOVAL; CHLORINATION; FILTRATION; OZONATION; WEIGHT; FRACTIONATION Addresses: Nissinen TK (reprint author), Natl Publ Hlth Inst, POB 95, Kuopio, FIN-70701 Finland Natl Publ Hlth Inst, Kuopio, FIN-70701 Finland Univ Kuopio, Dept Environm Sci, Kuopio, FIN-70211 Finland Publisher: PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND Subject Category: ENVIRONMENTAL SCIENCES IDS Number: 481EV

Title: Application of the flow field flow fractionation (FFFF) to the characterization of aquatic humic colloids: evaluation and optimization of the method Author(s): Thang NM, Geckeis H, Kim JI, Beck HP Source: COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS 181 (1-3): 289-301 JUN 15 2001 Document Type: Article Language: English Cited References: 33 Times Cited: 12 Abstract: The flow field flow fractionation (FFFF) is applied to determine the aquatic humic colloid size distribution. In order to determine average molecular weights of various aquatic humic acids, a calibration is carried out by using sulfonated polystyrene (PSS) reference colloids. Some interference is found to be inherent to the FFFF-method. Considerable sorption of humic substances to equipment components is observed depending on the ionic strength and pH of given carrier medium, the kind of membrane covering the accumulation wall, and the cross-flow rate. The present study shows that the sample recovery can be optimized by selecting a carrier of low ionic strength and high pH (5 x 10(-3) mol l(-1) Tris-buffer; pH = 9.1) and using a regenerated cellulose membrane (cutoff: 5 kDa related to globular proteins). Under these low ionic strength conditions, the molecular weight calibration by using sulfonated polystyrene standards (PSS) is affected by 'overloading' effects originating from charge repulsive interaction of particles with one another and also with the accumulation wall. In general, the elution time of PSS decreases with increasing concentration. A correction for the 'overloading' effects is made by extrapolating the measured elution volumes to those obtained for infinitely low PSS concentrations where charge repulsion effects disappear. The molecular weight determined by this method for different aquatic humic substances is found to be in the range of 1.1-1.8 kDa for the number averaged molecular weight (M-n) and 1.8-4.1 kDa for the weight averaged molecular weight (M-w). Results are compared with the available literature data. Discrepancies can be explained to some extent by different reference colloids used in other studies for calibration. (C) 2001 Elsevier Science B.V. All rights reserved. Author Keywords: flow-field flow fractionation; humic acid; fulvic acid; molecular weight distribution KeyWords Plus: MOLECULAR-WEIGHT DISTRIBUTIONS; FLUORESCENCE CORRELATION SPECTROSCOPY; DIFFUSION-COEFFICIENTS; LIGHT-SCATTERING; IONIC-STRENGTH; FULVIC-ACIDS; SIZE; GROUNDWATER; SUBSTANCES; BEHAVIOR Addresses: Geckeis H (reprint author), Forschungszentrum Karlsruhe, Inst Nukl Entsorgung, POB 3640, Karlsruhe, D-76021 Germany Forschungszentrum Karlsruhe, Inst Nukl Entsorgung, Karlsruhe, D-76021 Germany Univ Saarland, Saarbrucken, D-66041 Germany Publisher: ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS Subject Category: CHEMISTRY, PHYSICAL

Title: Conventional and optimized coagulation for NOM removal Author(s): Bell-Ajy K, Abbaszadegan M, Ibrahim E, Verges D, LeChevallier M Source: JOURNAL AMERICAN WATER WORKS ASSOCIATION 92 (10): 44-58 OCT 2000 Document Type: Article Language: English Cited References: 17 Times Cited: 7 Abstract: The evaluation of 16 sites with optimized coagulation (optimizing the pH of coagulation and then the coagulant dosage) provides an assessment of this coagulation technique and illustrates its capabilities to meet the requirements of the Disinfectants/Disinfection By-products (D/DBP) Rule. Jar tests were used to determine the effectiveness of optimized coagulation for the removal of organic carbon, DBP precursors, particles, and turbidity when supernatant results were compared with conventional (baseline) treatment. Jar-test results indicate that optimized coagulation can enhance the removal of organic carbon and DBP precursors. KeyWords Plus: ENHANCED COAGULATION Addresses: Bell-Ajy K (reprint author), Jordan Jones & Goulding, 2000 Clearview Ave NE, Atlanta, GA 30340 USA Jordan Jones & Goulding, Atlanta, GA 30340 USA Arizona State Univ, Tempe, AZ 85287 USA New Jersey Amer Water Co, Delran, NJ 08075 USA Amer Water Works Serv Co Lab, Belleville, IL 62220 USA Amer Water Works Co, Voorhees, NJ 08043 USA Publisher: AMER WATER WORKS ASSOC, 6666 W QUINCY AVE, DENVER, CO 80235 USA Subject Category: ENGINEERING, CIVIL; WATER RESOURCES IDS Number: 434VH

Title: HUMUS TRANSFORMATION AT THE BANK FILTRATION WATER-PLANT Author(s): MIETTINEN IT, MARTIKAINEN PJ, VARTIAINEN T Source: WATER SCIENCE AND TECHNOLOGY 30 (10): 179-187 1994 Document Type: Article Language: English Cited References: 20 Times Cited: 12 Abstract: Transformations in the amount and quality of organic matter (humus) during bank filtration of surface water were studied by analyzing the changes in total organic carbon (TOC), non-purgeable organic carbon (NPOC), chemical oxygen demand (GOD), color of water, and UV absorbing humus fractions. The amount of organic matter expressed as TOC, NPOC, and COD depended on temperature and filtration distance from lake water. The color of water and the UV absorbing humus peaks presenting different humus molecule fractions decreased more effectively than other parameters measuring the amount of organic matter in water. The ratio of COD to TOC decreased when the filtration distance of water increased. Our observations indicated that bank filtration of humus-rich lake water changed more the quality of organic matter than its total amount. Author Keywords: BANK FILTRATION; HUMUS; ORGANIC MATTER; TRANSFORMATION KeyWords Plus: DRINKING WATERS; ORGANIC-MATTER; CHROMATOGRAPHY Addresses: MIETTINEN IT (reprint author), NATL PUBL HLTH INST, DEPT ENVIRONM MICROBIOL, POB 95, KUOPIO, SF-70701 FINLAND NATL PUBL HLTH INST, DEPT ENVIRONM HYG, KUOPIO, SF-70701 FINLAND Publisher: PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB Subject Category: ENGINEERING, ENVIRONMENTAL; ENVIRONMENTAL

Title: BIODEGRADATION OF NOM - EFFECT OF NOM SOURCE AND OZONE DOSE Author(s): GOEL S, HOZALSKI RM, BOUWER EJ Source: JOURNAL AMERICAN WATER WORKS ASSOCIATION 87 (1): 90-105 JAN 1995 Document Type: Article Language: English Cited References: 31 Times Cited: 31 Abstract: Batch degradation experiments were conducted to evaluate the extent of biodegradation of natural organic matter (NOM) as a function of ozone dosage. Four NOM sources that might be encountered in drinking water treatment were characterized and tested. The biodegradability of all sources was enhanced as the ozone dose was increased from 0 to 7.3 mg ozone/mg total organic carbon (TOC). Increased ozonation resulted in consistently improved TOC removals for NOM sources having a large fraction of high- molecular-weight organics. Greater biodegradation was observed for the unozonated sources with lower UV-absorption-to-TOC ratios and a larger fraction of low-molecular- weight organics. KeyWords Plus: FULVIC-ACID; HUMIC ACIDS; WATER; OZONATION; PRODUCTS Addresses: GOEL S (reprint author), JOHNS HOPKINS UNIV, DEPT GEOG & ENVIRONM ENGN, 313 AMES HALL, 34TH & CHARLES ST, BALTIMORE, MD 21218 USA Publisher: AMER WATER WORKS ASSN, 6666 W QUINCY AVE, DENVER, CO 80235 Subject Category: ENGINEERING, CIVIL; WATER RESOURCES IDS Number: QC350 ISSN: 0003-150X

Title: Transformation of organic matter and bank filtration from a polluted stream Author(s): Cosovic B, Hrsak D, Vojvodic V, Krznaric D Source: WATER RESEARCH 30 (12): 2921-2928 DEC 1996 Document Type: Article Language: English Cited References: 19 Times Cited: 5 Abstract: A case study of the examination of the changes of organic matter in a small, highly polluted stream and the adjacent alluvial aquifer is presented. The investigated stream was actually a collector of effluents from baker's yeast and pharmaceutical industries. The stream was characterized by a COD of several thousands of mg O-2 l(-1), most of which was biodegradable organic matter. Biodegradation processes took place in the surface water, with consequent oxygen depletion in the stream. The organic matter content of the river sediment was more than 10% of its dry weight. Bank filtration of organic substances was investigated in a number of observation wells at distances of 5- 150 m from the river (under different hydrological conditions). The infiltration of organic matter from the polluted stream into the aquifer was found to be significant only at hydrological conditions where the water level exceeds the altitude of the stream bed. The organic matter present in groundwater samples was mainly a humic/fulvic type, and was not degraded during the 64 days of the laboratory biodegradation experiment. Copyright (C) 1996 Elsevier Science Ltd Author Keywords: polluted freshwater; organic matter; biodegradation; bank filtration; surface active substances KeyWords Plus: NATURAL-WATERS; SUBSTANCES Addresses: Cosovic B (reprint author), RUDJER BOSKOVIC INST, CTR MARINE RES ZAGREB, POB 1016, ZAGREB, HR-10001 CROATIA Publisher: PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB Subject Category: ENGINEERING, ENVIRONMENTAL; ENVIRONMENTAL SCIENCES; WATER RESOURCES IDS Number: WB774 ISSN: 0043-1354

Title: ADSORPTION BEHAVIOR OF THE HYDROPHOBIC FRACTION OF ORGANIC- MATTER IN NATURAL-WATERS Author(s): COSOVIC B, VOJVODIC V Source: MARINE CHEMISTRY 28 (1-3): 183-198 DEC 1989 Document Type: Article Language: English Cited References: 25 Times Cited: 29 Addresses: COSOVIC B (reprint author), RUDJER BOSKOVIC INST, CTR MARINE RES ZAGREB, ZAGREB, YU-41001 YUGOSLAVIA Publisher: ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS Subject Category: CHEMISTRY, MULTIDISCIPLINARY; OCEANOGRAPHY IDS Number: CG375 ISSN: 0304-4203

Title: MOBILITY OF NATURAL ORGANIC-MATTER IN A SANDY AQUIFER Author(s): MCCARTHY JF, WILLIAMS TM, LIANG LY, JARDINE PM, JOLLEY LW, TAYLOR DL, PALUMBO AV, COOPER LW Source: ENVIRONMENTAL SCIENCE & TECHNOLOGY 27 (4): 667-676 APR 1993 Document Type: Article Language: English Cited References: 43 Times Cited: 66 Abstract: Field-scale transport of natural organic matter (NOM) was studied in a two- well tracer test by injecting 80 000 L of ''brown water'' (66 mg of C L-1) from a wetlands pond into a shallow, sandy, coastal plain aquifer. The basic features of NOM breakthrough observed in laboratory column studies (extending tailing and rapid decline in concentrations when NOM inputs are terminated) were observed in the field. Retardation of NOM in the field agreed with predictions from laboratory studies. In spite of natural heterogeneities, fractionation of NOM subcomponents occurred in transport. Smaller (<3000 MW) and more hydrophilic (by XAD-8 chromatography) components of NOM were more mobile than were larger (3-100K MW), more hydrophobic components. However, over the 2-week injection, the solid and solution phase reached an apparent steady state with respect to NOM adsorption, resulting in the unretarded transport of even the hydrophobic and macromolecular NOM. The results indicate that NOM can exhibit considerable mobility in an aquifer and suggest that NOM could alter the transport of contaminants in groundwater. KeyWords Plus: GRADIENT TRACER EXPERIMENTS; INDIGENOUS BACTERIA; HUMIC SUBSTANCES; ACID TREATMENT; CARBON; TRANSPORT; ADSORPTION; WATER; FRACTIONATION; CONTAMINANTS Addresses: MCCARTHY JF (reprint author), OAK RIDGE NATL LAB, DIV ENVIRONM SCI, OAK RIDGE, TN 37831 USA CLEMSON UNIV, BARUCH FOREST SCI INST, GEORGETOWN, SC 29442 USA Publisher: AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 Subject Category: ENGINEERING, ENVIRONMENTAL; ENVIRONMENTAL SCIENCES IDS Number: KU952 ISSN: 0013-936X

Title: Characterizing dissolved organic carbon using asymmetrical flow field- flow fractionation with on-line UV and DOC detection Author(s): Reszat TN, Hendry MJ Source: ANALYTICAL CHEMISTRY 77 (13): 4194-4200 JUL 1 2005 Document Type: Article Language: English Cited References: 41 Times Cited: 0 Abstract: A method of characterizing dissolved organic carbon (DOC) by asymmetrical flow field-flow fractionation with on-line UV and DOC detection is described and applied to standards and natural water samples. Poly(styrenesulfonate) polymer standards, Suwannee River humic standards, and naturally occurring surface water and groundwater DOC were analyzed using this coupled detection technique. Molecular weight determinations in the samples and standards were 6-30% lower with DOC analysis than UV analysis. This difference was attributed to the insensitivity of the latter technique to nonaromatic carbon and suggests the molecular weight determined with the DOC detector is a more accurate representation of the actual molecular weight of the DOC. A normalized intensity comparison (NIC) method was proposed to distinguish differences in the relative amounts of aromatic and aliphatic carbon in DOC by comparing the two detector responses. The NIC method was applied to yield an average aromatic content of the bulk DOC and to detail the aromatic content over a range of molecular weights in a single DOC fraction. KeyWords Plus: MOLECULAR-WEIGHT DISTRIBUTIONS; SIZE-EXCLUSION CHROMATOGRAPHY; CLAY-RICH AQUITARD; HUMIC SUBSTANCES; FULVIC-ACIDS; PORE WATERS; MATTER; OPTIMIZATION; COLLOIDS; AQUIFER Addresses: Reszat TN (reprint author), Univ Saskatchewan, Dept Geol Sci, Saskatoon, SK S7N 5E2 Canada Univ Saskatchewan, Dept Geol Sci, Saskatoon, SK S7N 5E2 Canada E-mail Addresses: [email protected] Publisher: AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 USA Subject Category: CHEMISTRY, ANALYTICAL Title: Mobile organic sorbent affected contaminant transport in soil: Numerical case studies for enhanced and reduced mobility Author(s): Totsche KU, Kogel-Knabner I Source: VADOSE ZONE JOURNAL 3 (2): 352-367 MAY 2004 Document Type: Article Language: English Cited References: 61 Times Cited: 1 Abstract: Mobile organic sorbents (MOS) such as dissolved and colloidal phase organic matter control flow of water and transport of solutes in soils. We studied the effect of MOS on contaminant fate by systematic numerical case studies. The scenarios considered were (i) enhanced mobility, (ii) reduced mobility due to cosorption, and (iii) reduced due to cumulative sorption. The enhanced mobility and cosorption scenario require contaminant sorption to the MOS. The cosorption and cumulative sorption scenario require sorption of MOS to the immobile sorbent. Simulations were run for physicochemically different fractions of dissolved organic matter and two-model contaminants. Mobile organic sorbents mobility is characterized by a wide range of retardation parameters. Continued import of MOS to subsoil material high in MOS-specific sorption sites will increase the solid phase organic matter content. Enhanced mobility was observed for soils without MOS-specific sorption sites or for situations where MOS are in sorptive equilibrium with the immobile sorbent. Cosorption resulted in reduced contaminant mobility. The extent to which reduced mobility was observed depended on the ratio of the affinities of the free contaminant and the MOS-bound contaminant. As the sorption of the MOS-bound contaminants is controlled by the properties of the MOS, the characterization of these properties is a crucial step for the estimation of the effect of MOS on contaminant mobility. Cumulative sorption resulted in reduced contaminant mobility as well. However, this result is the consequence of the increase of the sorption capacity due to the sorption of MOS, a long-term process that may last for years to decades. KeyWords Plus: POLYCYCLIC AROMATIC-HYDROCARBONS; REACTIVE SOLUTE TRANSPORT; UNSATURATED POROUS-MEDIA; FACILITATED TRANSPORT; IMMOBILE SORBENTS; MATTER SORPTION; COLLOIDS; CARBON; FRACTIONS; COLUMNS Addresses: Totsche KU (reprint author), Tech Univ Munich, Lehrstuhl Bodenkunde, Dept Okol, Wissensch Zentrum Weihenstephan, Freising Weihenstephan, D-85350 Germany Tech Univ Munich, Lehrstuhl Bodenkunde, Dept Okol, Wissensch Zentrum Weihenstephan, Freising Weihenstephan, D-85350 Germany E-mail Addresses: [email protected] Publisher: SOIL SCI SOC AMER, 677 SOUTH SEGOE ROAD, MADISON, WI 53711 USA Subject Category: AGRICULTURE, SOIL SCIENCE; ENVIRONMENTAL SCIENCES; WATER RESOURCES IDS Number: 904BA

Title: The simultaneous modelling of metal ion and humic substance transport in column experiments Author(s): Bryan ND, Barlow J, Warwick P, Stephens S, Higgo JJW, Griffin D Source: JOURNAL OF ENVIRONMENTAL MONITORING 7 (3): 196-202 2005 Document Type: Article Language: English Cited References: 29 Times Cited: 0 Abstract: Pulsed column experiments using Co, fulvic acid and porous sediment packing, along with up/down-flooding experiments using Eu, humic acid and intact sandstone blocks have been performed. The elution of metal and humic and their distribution along the sandstone columns have been measured. A mixed equilibrium and kinetic coupled chemical transport model has been used to simulate the results. In both cases, one exchangeable and one non-exchangeable component have been used to simulate the interaction of metal and humic substance. For the pulsed experiments, a simple equilibrium approach was used to model humic sorption, while a two component, kinetic model was required for the sandstone columns. KeyWords Plus: NATURAL ORGANIC-MATTER; IRON-OXIDE; COMPETITIVE ADSORPTION; SANDY AQUIFER; DESORPTION; SORPTION; ACIDS; DISPLACEMENT; PARTICLES; MOBILITY Addresses: Bryan ND (reprint author), Univ Manchester, Dept Chem, Ctr Radiat Res, Oxford Rd, Manchester, Lancs M13 9PL England Univ Manchester, Dept Chem, Ctr Radiat Res, Manchester, Lancs M13 9PL England Univ Loughborough, Dept Chem, Loughborough, Leics England British Geol Survey, Keyworth, Notts NG12 5GG England RMC Ltd, Abingdon, Oxon England Publisher: ROYAL SOC CHEMISTRY, THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND Subject Category: ENVIRONMENTAL SCIENCES IDS Number: 901LT ISSN: 1464-0325

Title: Measuring the pollutant transport capacity of dissolved organic matter in complex matrixes Author(s): Persson L, Alsberg T, Odham G, Ledin A Source: INTERNATIONAL JOURNAL OF ENVIRONMENTAL ANALYTICAL CHEMISTRY 83 (12): 971-986 DEC 2003 Document Type: Article Language: English Cited References: 56 Times Cited: 0 Abstract: Dissolved organic matter (DOM) facilitated transport in contaminated groundwater was investigated through the measurement of the binding capacity of landfill leachate DOM (Vejen, Denmark) towards two model pollutants (pyrene and phenanthrene). Three different methods for measuring binding capacity were used and evaluated, head-space solid-phase micro-extraction (HS-SPME), enhanced solubility (ES) and fluorescence quenching (FQ). It was concluded that for samples with complex matrixes it was possible to measure the net effect of the DOM binding capacity and the salting out effect of the matrix. It was further concluded that DOM facilitated transport should be taken into account for non-ionic PAHs with lg K OW above 5, at DOM concentrations above 250 mg C/L. The total DOM concentration was found to be more important for the potential of facilitated transport than differences in the DOM binding capacity. Author Keywords: leachate; groundwater; dissolved organic matter; solid-phase micro extraction; fluorescence quenching; enhanced solubility KeyWords Plus: POLYCYCLIC AROMATIC-HYDROCARBONS; SOLID-PHASE MICROEXTRACTION; AQUATIC HUMIC SUBSTANCES; LEACHATE PLUME VEJEN; LANDFILL-LEACHATE; SOLUBILITY ENHANCEMENT; FACILITATED TRANSPORT; MOLECULAR-WEIGHT; PYRENE SORPTION; MODEL POLYMERS Addresses: Persson L (reprint author), Stockholm Univ, Inst Appl Environm Res, Stockholm, S-10691 Sweden Stockholm Univ, Inst Appl Environm Res, Stockholm, S-10691 Sweden Tech Univ Denmark, Environm & Resources DTU, Lyngby, Denmark E-mail Addresses: [email protected] Publisher: TAYLOR & FRANCIS LTD, 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND Subject Category: CHEMISTRY, ANALYTICAL; ENVIRONMENTAL SCIENCES IDS Number: 762QU

Title: Adsorption of natural organic matter to air-water interfaces during transport through unsaturated porous media Author(s): Lenhart JJ, Saiers JE Source: ENVIRONMENTAL SCIENCE & TECHNOLOGY 38 (1): 120-126 JAN 1 2004 Document Type: Article Language: English Cited References: 45 Times Cited: 0 Abstract: To better understand how interactions with the air phase influence the movement of natural organic matter (NOM) through the vadose zone,we measured the transport of soil-humic acid (SHA) through laboratory columns packed with partially saturated sand. Our results demonstrate that sorptive reactions at air-water interfaces reduce SHA mobility and that the affinity of SHA for the air phase increases as the porewater pH declines from 8 to 3.9. SHA desorption from air-water interfaces is negligible for conditions of constant pH, but release of bound SHA occurs in response to perturbations in porewater pH. We analyzed the effluent samples collected from our laboratory columns using high-performance size-exclusion chromatography. The results of this analysis demonstrate that the SHA did not fractionate appreciably during transport through the columns, suggesting that the various components of the SHA pool (as distinguished on the basis of molecular weight) express an equal affinity for the air-water interfaces over the range of pH conditions tested. A mathematical model incorporating irreversible, second-order rate laws to simulate adsorption at air-water and solid-water interfaces closely describes the SHA breakthrough data. The mass-transfer parameters that govern this model vary in a discernible fashion with changes in porewater pH, and the parameter trends are consistent with published theories for SHA adsorption. KeyWords Plus: AQUATIC HUMIC SUBSTANCES; SIZE-EXCLUSION CHROMATOGRAPHY; POLY-ELECTROLYTE ADSORPTION; MOLECULAR-WEIGHT; POLYELECTROLYTE ADSORPTION; MINERAL PARTICLES; SURFACE-TENSION; ACID ADSORPTION; IONIC- STRENGTH; ALUMINUM-OXIDE Addresses: Saiers JE (reprint author), Yale Univ, Sch Forestry & Environm Studies, 205 Prospect St, New Haven, CT 06511 USA Yale Univ, Sch Forestry & Environm Studies, New Haven, CT 06511 USA Publisher: AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 USA Subject Category: ENGINEERING, ENVIRONMENTAL; ENVIRONMENTAL SCIENCES

Title: Impact of dissolved organic matter on copper mobility in aquifer material Author(s): Han NZ, Thompson ML Source: JOURNAL OF ENVIRONMENTAL QUALITY 32 (5): 1829-1836 SEP-OCT 2003 Document Type: Article Language: English Cited References: 34 Times Cited: 1 Abstract: Naturally occurring dissolved organic matter (DOM) and biosolids-derived DOM have been implicated in the mobility of metals in soils and aquifer materials. To investigate the effect of DOM on copper mobility in aquifer material, DOM derived from sewage biosolids was separated into two apparent molecular-weight (MW) fractions, 500 to 3500 Da (LMW) and >14 000 Da (HMW). In each MW fraction, the DOM was further fractionated into hydrophilic, hydrophobic acid, and hydrophobic neutral compounds by an XAD-8 chromatography technique. The mobility of these DOM components and their influences on copper transport in a sesquioxide-coated, sandy aquifer material were examined with column transport experiments. The LMW DOM was found to be highly mobile, whereas the HMW DOM had a greater tendency to be retained by the aquifer material. Within the same MW fraction, the mobility of DOM followed the order of hydrophilic DOM > hydrophobic acid DOM > hydrophobic neutral DOM. Copper breakthrough curves in the presence of various DOM components showed that, except for the HMW hydrophilic fraction, DOM components enhanced Cu transport through the aquifer columns at early stages of transport (the first 75 pore volumes). In the later stages, however, all the DOM components substantially inhibited Cu mobility. We hypothesize that several mechanisms could account for retardation of Cu movement in the presence of the DOM fractions, including the formation of ternary complexes between the aquifer material, Cu, and DOM; changes in the electrostatic potential at the solid- phase surface; and pH buffering by DOM. KeyWords Plus: HUMIC SUBSTANCES; PREPARATIVE ISOLATION; SEWAGE-SLUDGE; AMENDED SOILS; HEAVY-METALS; CARBON; COLUMNS; ADSORPTION; MECHANISMS; BIOSOLIDS Addresses: Thompson ML (reprint author), Iowa State Univ, Dept Agron, Ames, IA 50011 USA Iowa State Univ, Dept Agron, Ames, IA 50011 USA Virginia Polytech Inst & State Univ, Dept Geol Sci, Blacksburg, VA 24061 USA Publisher: AMER SOC AGRONOMY, 677 S SEGOE RD, MADISON, WI 53711 USA Subject Category: ENVIRONMENTAL SCIENCES

Title: Flow and reactivity effects on dissolved organic matter transport in soil columns Author(s): Weigand H, Totsche KU Source: SOIL SCIENCE SOCIETY OF AMERICA JOURNAL 62 (5): 1268-1274 SEP-OCT 1998 Document Type: Article Language: English Cited References: 34 Times Cited: 26 Abstract: Dissolved organic matter (DOM) plays a prominent role in the transport of contaminants in porous media. As DOM has to be considered as a reactive component, now regime and sorbent reactivity should affect overall DOM transport in an important way. We focused on DOM transport in unsaturated column experiments using quartz sand (QS) and goethite-coated quartz sand (GS). Rate constrictions to DOM sorption were investigated by varying the volumetric now rate, while extent and reversibility of sorption were studied in consecutive adsorption and desorption steps. In the QS, DOM retention was low and unaffected by changes in now rate. Desorption-step breakthrough curves (BTCs) and mass balances show full reversibility of the sorption process. However, DOM retention in GS was significant and sensitive to now variation, indicative of nonequilibrium sorption. At lower now rates, DOM breakthrough exhibited a change in curvature (shoulder) due to the superimposition of two BTCs representing reactive and nonreactive DOM fractions. Transport was successfully modeled assuming these two fractions governed overall DOM mobility. At higher flow rates, the BTC shoulder vanished due to reduced contact time between the DOM and the solid phase (rate-limited sorption). Sorption of DOM on GS is accompanied by a marked rise in effluent pH, indicative of a ligand-exchange mechanism. Recovery of DOM during desorption was incomplete due to either partially irreversible sorption or strongly rate-limited desorption. Increased DOM mobility in the consecutive adsorption step resulted from partial blocking of sorption sites by the initial pulse of DOM. KeyWords Plus: POLYCYCLIC AROMATIC-HYDROCARBONS; AQUATIC HUMIC SUBSTANCES; IMMOBILE SORBENTS; SOLUTE TRANSPORT; ALUMINUM-OXIDE; SANDY AQUIFER; IRON-OXIDE; ADSORPTION; CARBON; DISPLACEMENT Addresses: Totsche KU (reprint author), Univ Bayreuth, Soil Phys Div, Bayreuth, D- 95440 Germany Univ Bayreuth, Soil Phys Div, Bayreuth, D-95440 Germany E-mail Addresses: [email protected] Publisher: SOIL SCI SOC AMER, 677 SOUTH SEGOE ROAD, MADISON, WI 53711 USA Subject Category: AGRICULTURE, SOIL SCIENCE

Title: Competitive adsorption, displacement, and transport of organic matter on iron oxide .2. Displacement and transport Author(s): Gu BH, Mehlhorn TL, Liang LY, McCarthy JF Source: GEOCHIMICA ET COSMOCHIMICA ACTA 60 (16): 2977-2992 AUG 1996 Document Type: Article Language: English Cited References: 39 Times Cited: 26 Abstract: The competitive interactions between organic matter compounds and mineral surfaces are poorly understood, yet these interactions may play a significant role in the stability and co-transport of mineral colloids and/or environmental contaminants. In this study, the processes of competitive adsorption, displacement, and transport of Suwannee River natural organic matter (SR-NOM) are investigated with several model organic compounds in packed beds of iron oxide-coated quartz columns. Results demonstrated that strongly-binding organic compounds are competitively adsorbed and displace those weakly-bound organic compounds along the flow path. Among the four organic compounds studied, polyacrylic acid (PAA) appeared to be the most competitive, whereas SR-NOM was more competitive than phthalic and salicylic acids. The transport of SR-NOM is found to involve a complex competitive interaction and displacement of different NOM subcomponents. A diffuse adsorption and sharp desorption front (giving an appearance of irreversible adsorption) of the SR-NOM breakthrough curves are explained as being a result of the competitive time-dependent adsorption and displacement processes between different organic components within the SR-NOM. The stability and transport of iron oxide colloids varied as one organic component competitively displaces another. Relatively large quantities of iron oxide colloids are transported when the more strongly-binding PAA competitively displaces the weakly-binding SR-NOM or when SR-NOM competitively displaces phthalic and salicylic acids. Results of this study suggest that the chemical composition and hence the functional behavior of NOM (e.g., in stabilizing mineral colloids and in complexing contaminants) can change along its flow path as a result of the dynamic competitive interactions between heterogeneous NOM subcomponents. Further studies are needed to better define and quantify these NOM components as well as their roles in contaminant partitioning and transport. KeyWords Plus: CARBOXYL-GROUP STRUCTURES; HUMIC SUBSTANCES; AQUIFER MATERIAL; WATER INTERFACE; SUWANNEE RIVER; SANDY AQUIFER; FULVIC-ACID; COLUMNS; MODELS; RETENTION Addresses: Gu BH (reprint author), OAK RIDGE NATL LAB, DIV ENVIRONM SCI, POB 2008, OAK RIDGE, TN 37831 USA Publisher: PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB Subject Category: GEOCHEMISTRY & GEOPHYSICS

Title: The sorption of organic matter in soils as affected by the nature of soil carbon Author(s): Kaiser K, Haumaier L, Zech W Source: SOIL SCIENCE 165 (4): 305-313 APR 2000 Document Type: Article Language: English Cited References: 38 Times Cited: 8 Abstract: Recent studies have shown that soil organic carbon (OC) may either hinder or favor the sorption of dissolved organic matter (DOM) in soils. Our concept was that the nature of soil OC determines these contrasting findings. To test this hypothesis, we compared the DOM sorption in soils with OC derived from biomass decomposition with that in soils with OC more likely derived from charred materials (black carbon). All the mineral soil samples in the study were from Spodosols, and the DOM was from an aqueous extract of a mor forest floor layer. Sorption was determined in batch experiments. The sorption in soils that contain large amounts of black carbon was, in general, less than the sorption in soils with decomposition-derived OC, When the DOM sorption parameters of the soils were correlated to the OC content, the black carbon soils showed a positive effect of the OC content on the DOM sorption, In the soils lacking the features of black carbon residues, the DOM sorption was negatively influenced by OC, These results lead us to assume that the nature of soil OC is a soil property that needs to be considered in the DOM sorption of soils, especially when soils have large amounts of highly aromatic OC. Author Keywords: dissolved organic matter; sorption; soil organic carbon; black carbon KeyWords Plus: HUMIC SUBSTANCES; FOREST SOIL; ADSORPTION; ACIDS; SPECTROSCOPY; NMR; FRACTIONS; CHEMISTRY; C-13-NMR Addresses: Kaiser K (reprint author), Univ Bayreuth, Inst Soil Sci & Soil Geog, POB 101251, Bayreuth, D-95440 Germany Univ Bayreuth, Inst Soil Sci & Soil Geog, Bayreuth, D-95440 Germany Publisher: LIPPINCOTT WILLIAMS & WILKINS, 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA Subject Category: AGRICULTURE, SOIL SCIENCE IDS Number: 309MY ISSN: 0038-075X

Title: Lanthanide field tracers demonstrate enhanced transport of transuranic radionuclides by natural organic matter Author(s): McCarthy JF, Sanford WE, Stafford PL Source: ENVIRONMENTAL SCIENCE & TECHNOLOGY 32 (24): 3901-3906 DEC 15 1998 Document Type: Article Language: English Cited References: 28 Times Cited: 23 Abstract: Transuranic (TRU) radionuclides buried 25 years ago in shallow un lined disposal trench es in a fractured shale saprolite had been detected in groundwater from downgradient monitoring wells and in surface water seeps. Field observations had suggested the actinide radionuclides were mobilized by natural organic matter(NOM) and rapidly transported with little retardation. A 73-day natural gradient tracer experiment injected trivalent lanthanides (Nd and Eu) as analogues to determine the mechanisms and rates of actinide transport at the field scale. Adsorption isotherms for Am-241 and Eu with saprolite from the site confirmed a very high affinity for adsorption (R > 50 000) in the absence of NOM. However, reactive and nonreactive tracers arrived at approximately the same time along a 10-m long deep flow path, and anion-exchange chromatography and filtration suggested that the mobile lanthanides in groundwater were a NOM complex. Although flow through a shallow flow path was intermittent, reflecting transient recharge events, large storms resulted in coincident peaks of both reactive and nonreactive tracers, suggesting that they migrated at similar rates over distances of 78 m. We conclude that NOM facilitated the almost-unretarded transport of lanthanide tracers and, by analogy, that NOM is facilitating the mobilization and rapid migration of the TRU radionuclides. KeyWords Plus: HUMIC-ACID; ADSORPTION; EUROPIUM; SORPTION; AQUIFER; SOIL; PH Addresses: McCarthy JF (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008,Bethel Valley Rd, Oak Ridge, TN 37831 USA Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA Colorado State Univ, Dept Earth Resources, Ft Collins, CO 80523 USA Univ Tennessee, Dept Geol Sci, Knoxville, TN USA Publisher: AMER CHEMICAL SOC, 1155 16TH ST, NW, WASHINGTON, DC 20036 USA

Title: A seasonal survey of carbohydrates and uronic acids in the Trinity River, Texas Author(s): Hung CC, Warnken KW, Santschi PH Source: ORGANIC GEOCHEMISTRY 36 (3): 463-474 2005 Document Type: Article Language: English Cited References: 58 Times Cited: 0 Abstract: Due to their potential significance as indicators of ecological health, the biogeochemical cycling of carbohydrates and uronic acids was investigated in the Trinity River Texas, during 2000 2001. Concentrations of dissolved organic carbon (DOC), total carbohydrates (TCHO), polysaccharides (PCHO), monosaccharides (MCHO), uronic acids (URA), as well as of oxygen, suspended particulate matter, nutrients and trace metals (Cu, Pb, Cd) were assessed at various stages of discharge. TCHO/DOC ratios, as well as nutrient and hydrogen ion concentrations, were inversely related to temperature, which suggests that biological processes in Lake Livingston, the largest freshwater reservoir along the Trinity River, are not only regulating nutrient concentrations but also the preferential degradation of carbohydrates over that of bulk DOC. However, uronic acids were selectively preserved during this temperature controlled biological process, as is evident from the positive correlation of URA/TCHO ratios and temperature. Thus, uronic acids are more refractory compounds than bulk TCHO. Significant correlations between TCHO and dissolved Cu, Pb and Cd suggest that their pathways and cycles are linked through common sources or removal processes. (C) 2004 Published by Elsevier Ltd. KeyWords Plus: DISSOLVED ORGANIC-MATTER; GALVESTON BAY; MISSISSIPPI RIVER; ESTUARINE WATERS; DIFFERENT ROLES; SURFACE WATERS; FULVIC-ACIDS; TRACE- METALS; CARBON; COPPER Addresses: Hung CC (reprint author), Univ Lancaster, Dept Environm Sci, Inst Environm & Nat Sci, Lancaster, LA1 4YQ England Texas A&M Univ, Dept Marine Sci, LOER, Galveston, TX 77551 USA E-mail Addresses: [email protected], [email protected] Publisher: PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND Subject Category: GEOCHEMISTRY & GEOPHYSICS

Title: Identification of wastewater dissolved organic carbon characteristics in reclaimed wastewater and recharged groundwater Author(s): Fujita Y, Ding WH, Reinhard M Source: WATER ENVIRONMENT RESEARCH 68 (5): 867-876 JUL-AUG 1996 Document Type: Article Language: English Cited References: 41 Times Cited: 21 Abstract: Nonvolatile dissolved organic carbon (DOC) in reclaimed wastewaters and groundwater was characterized and indicators of wastewater origin were identified. Over 50% of the DOC in activated carbon and reverse osmosis effluents was classified as hydrophilic, and no humic acid was isolated. In groundwater partially recharged by the reclaimed wastewaters, only 16% of the DOC was hydrophilic, 50% of the DOC was fulvic acid, and humic acid was recovered. The H:C ratios of the isolated fulvic acids were higher in the wastewaters and recharged groundwater than in a deep well water not affected by recharge. N:C ratios in the wastewater and recharged groundwater fulvic and humic acid fractions were also higher than in the deep well water. The H-1 NMR spectra of the effluent and recharged groundwater fulvic acid fractions exhibited a characteristic fingerprint pattern, indicating a correlation between origin and spectral appearance. Gas chromatography-mass spectrometry analysis confirmed the presence of specific trace organic compounds, including EDTA and alkylphenol polyethoxylate residues, in the wastewaters and recharged groundwater. Author Keywords: reclaimed wastewater; groundwater recharge; DOC KeyWords Plus: ALKYLPHENOL POLYETHOXYLATE SURFACTANTS; HUMIC SUBSTANCES; PREPARATIVE ISOLATION; AQUATIC ENVIRONMENT; WATER-TREATMENT; P-XYLENE; ACID; BEHAVIOR; TRANSFORMATION; CARBOXYLATES Addresses: Fujita Y (reprint author), STANFORD UNIV, DEPT CIVIL ENGN, STANFORD, CA 94305 USA Publisher: WATER ENVIRONMENT FEDERATION, 601 WYTHE ST, ALEXANDRIA, VA 22314-1994 Subject Category: ENGINEERING, ENVIRONMENTAL; ENVIRONMENTAL SCIENCES; LIMNOLOGY; WATER RESOURCES IDS Number: UY297

Title: Fate of organics during soil-aquifer treatment: sustainability of removals in the field Author(s): Quanrud DM, Hafer J, Karpiscak MM, Zhang HM, Lansey KE, Arnold RG Source: WATER RESEARCH 37 (14): 3401-3411 AUG 2003 Document Type: Article Language: English Cited References: 37 Times Cited: 4 Abstract: A 5-year program of study was conducted at the Sweetwater Recharge Facilities (SRF) to assess the performance of surface spreading operations for organics attenuation during field-scale soil-aquifer treatment (SAT) of municipal wastewater. Studies were conducted utilizing both mature (similar to 10 yr old) and new infiltration basins. Removals of dissolved organic carbon (DOC) were robust, averaging > 90 percent during percolation through the local 37-m vadose zone. The hydrophilic (most polar) fraction of DOC was preferentially removed during SAT; removals were attributed primarily to biodegradation. Reductions in trihalomethane formation potential (THMFP) averaged 91 percent across the vadose zone profile. The reactivity (specific THMFP) of post-SAT organic residuals with chlorine decreased slightly from pre-SAT levels (60 vs. 72 mug THM per mg DOC, respectively). Variations in the duration of wetting/drying periods did not significantly impact organic removal efficiencies. (C) 2002 Elsevier Science Ltd. All rights reserved. Author Keywords: soil-aquifer treatment; wastewater effluent; dissolved organic carbon; trihalomethanes KeyWords Plus: CHLORINATION BY-PRODUCTS; RECLAIMED WATER; DRINKING- WATER; WASTE-WATER; GROUNDWATER RECHARGE; SPONTANEOUS-ABORTION; MATTER; IDENTIFICATION; CALIFORNIA; EFFLUENTS Addresses: Quanrud DM (reprint author), Univ Arizona, Dept Civil Engn & Engn Mech, Tucson, AZ 85721 USA Univ Arizona, Dept Civil Engn & Engn Mech, Tucson, AZ 85721 USA Univ Arizona, Dept Environm Chem & Engn, Tucson, AZ 85721 USA Univ Arizona, Off Arid Lands Studies, Tucson, AZ 85721 USA Publisher: PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND Subject Category: ENGINEERING, ENVIRONMENTAL; ENVIRONMENTAL SCIENCES; WATER RESOURCES IDS Number: 701LH

Title: Relative influence of bioturbation and predation on organic matter processing in river sediments: a microcosm experiment Author(s): Mermillod-Blondin F, Gaudet JP, Gerino M, Desrosiers G, Jose J, des Chatelliers MC Source: FRESHWATER BIOLOGY 49 (7): 895-912 JUL 2004 Document Type: Article Language: English Cited References: 64 Times Cited: 1 Abstract: 1. Our objective was to measure the effects of bioturbation and predation on the physical characteristics and biogeochemical processes in river sediments. 2. We investigated the impacts of tubificid worms tested separately and together with an omnivore (Gammarus pulex), which does feed on tubificids, on sediment distribution, water flux, sediment organic carbon, biofilm biomass and microbial activities, and the concentrations of dissolved oxygen, dissolved organic carbon, PO43-, NO3-, NO2- and NH4+ in slow filtration sand-gravel columns. We hypothesised that gammarids, which exploit the top 2-3 cm of the sediment, would modify the impact of worms at the sediment surface. 3. In experiments both with and without gammarids, bioturbation by the tubificids modified both the distribution of surface particles in the sediment column and water flux. In addition, microbial aerobic (oxygen consumption) and anaerobic (denitrification and fermentative decomposition of organic matter) processes in the sediment were stimulated in the presence of tubificid worms. However, G. pulex did not affect either the density or bioturbation activity of the tubificid worms. 4. Bioturbation by the benthos can be a major process in river habitats, contributing to the retention of organic matter in sediment dynamics. The presence of at least one predator had no effect on bioturbation in sediments. In such systems, physical heterogeneity may be sufficient for tubificids to escape from generalist predators, though more specialised ones might have more effect. Author Keywords: ecosystem engineers; functional diversity; interstitial invertebrates; microbial activity; river sediments KeyWords Plus: HYPORHEIC ZONE; FUNCTIONAL DIVERSITY; ECOSYSTEM ENGINEERS; SOLUTE TRANSPORT; TROPICAL STREAM; LAKE-SEDIMENTS; POROUS-MEDIA; ETS ACTIVITY; INVERTEBRATES; WATER Addresses: Mermillod-Blondin F (reprint author), Univ Lyon 1, CNRS, UMR 5023, LEHF, Domaine Sci de la Doua, Villeurbanne, F-69622 France Univ Lyon 1, CNRS, UMR 5023, LEHF, Villeurbanne, F-69622 France UJF, CNRS,UMR 5564, LTHE, INPG,IRD, Grenoble, France UPS, CNRS, FRE 2630, LEH, Toulouse, France Univ Quebec, ISMER, Rimouski, PQ G5L 3A1 Canada Univ Lyon 1, EA 1890, LICAS, Villeurbanne, France E-mail Addresses: [email protected]

Title: Environmental determinants of bacterial activity and faunal assemblages in alluvial riverbank aquifers Author(s): Mauclaire L, Gibert J Source: ARCHIV FUR HYDROBIOLOGIE 152 (3): 469-487 OCT 2001 Document Type: Article Language: English Cited References: 53 Times Cited: 1 Abstract: Groundwater quality can be strongly influenced by the source of the water through the contributions of oxygen, organic, and inorganic materials. Microbial characteristics (abundance and activity) and faunal distribution were examined in groundwater collected from two aquifers that are characterized by different water sources. For both aquifers, water samples were collected from three wells at different depths, three times in the year. The two aquifers showed contrasting characteristics concerning hydrodynamic variables, carbon content and presence of electron acceptors (oxygen and nitrate). At the local scale, spatial variations were low compared to seasonal changes. The combination of five variables (aquifer transmissivity, temperature, oxygen, dissolved organic carbon (DOC), and percentage of biodegradable DOC (BDOC)) accounted for 57 % of the variability in bacterial activity (expressed as the percentage of Electron Transport System active bacteria). The best multivariate linear regression model of faunal abundance accounted for 52 % of the variability with 5 significant variables (aquifer transmissivity, oxygen, DOC, redox, and pH). At the regional scale, the different water sources have consequences on spatial variations of chemical and biological water quality. Author Keywords: groundwater; groundwater fauna; bacterial activity; DOC KeyWords Plus: DEEP SUBSURFACE SEDIMENTS; DISSOLVED ORGANIC-MATTER; RESPIRING BACTERIA; RHONE RIVER; GROUNDWATER; MICROFLORA; DIVERSITY; NUTRIENTS; EXCHANGE; ANIMALS Addresses: Mauclaire L (reprint author), Univ Lyon 1, CNRS, ESA Hydrosyst Fluviaux 5023, 43 Bd 11 Novembre 1918, Villeurbanne, F-69622 France Univ Lyon 1, CNRS, ESA Hydrosyst Fluviaux 5023, Villeurbanne, F-69622 France Swiss Fed Inst Technol, Inst Terr Ecol, Schlieren, CH-8952 Switzerland Publisher: E SCHWEIZERBARTSCHE VERLAGS, NAEGELE U OBERMILLER JOHANNESSTRASSE 3A, D 70176 STUTTGART, GERMANY Subject Category: LIMNOLOGY; MARINE & FRESHWATER BIOLOGY IDS Number: 491LA ISSN: 0003-9136

Title: Bacterial enzyme activities in ground water during bank filtration of lake water Author(s): Miettinen IT, Vartiainen T, Martikainen PJ Source: WATER RESEARCH 30 (10): 2495-2501 OCT 1996 Document Type: Article Language: English Cited References: 37 Times Cited: 13 Abstract: The interactions between organic matter, bacterial biomass, enzyme activities and environmental factors were studied during bank filtration of humus-rich lake water. The exoenzymatic beta-glucosidase, phosphatase and alanine-aminopeptidase activities in water were measured in vitro as release of fluorescing degradation products from methylumbelliferyl substrates. The total enzymatic decomposition activity was mesured as the hydrolysis of fluorescein diacetate (FDA). Bacterial enzymatic activities decreased strongly after infiltration of lake water. The decrease in the enzyme activities correlated with decrease in bacterial counts and biomass production. However, the increase in specific FDA-hydrolysis activity (activity per bacterial cell) indicated that maintenance energy requirements increased during filtration in the ground. There was also an increase in the specific phosphatase activity, which might be associated with the decrease in the concentration of available phosphate. All enzyme activities depended on seasonal temperature changes. The highest FDA-hydrolysis, phosphatase and beta-glucosidase activities occurred during the summer months, when the bacterial production activity and the demand of essential nutrients were highest. On the contrary, the alanine- aminopeptidase activity was highest during autumn and winter, probably as a result of infiltrated nitrogenous material from senescing and dying microbes and algae in lake water. The close correlations between enzymatic activities and other microbial parameters suggest that enzyme activities can be used to monitor the changes in microbiological quality of water during bank filtration of lake water. Copyright (C) 1996 Elsevier Science Ltd Author Keywords: bacteria; bank filtration; enzyme activities; ground water; lake water; organic matter; phytoplankton KeyWords Plus: EUTROPHIC LAKE; FLUORESCEIN DIACETATE; ORGANIC-MATTER; HYDROLYSIS; BIOMASS; CARBON; HUMUS; SOIL Addresses: Miettinen IT (reprint author), NATL PUBL HLTH INST, LAB ENVIRONM MICROBIOL, POB 95, KUOPIO, FIN-70701 FINLAND NATL PUBL HLTH INST, ENVIRONM CHEM LAB, KUOPIO, FIN-70701 FINLAND Publisher: PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB Subject Category: ENGINEERING, ENVIRONMENTAL; ENVIRONMENTAL SCIENCES; WATER RESOURCES IDS Number: VT980

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