DOCSLIB.ORG

Submitted to COALTECH Research Association Native Species Trial

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Submitted to COALTECH Research Association Native Species Trial The Evaluation of Three Native Grass Species and a Tree Species as a Vegetation Option for Coal Mine Rehabilitation on the Mpumalanga Highveld of South Africa By Martin Platt Submitted to COALTECH Research Association Native Species Trial 1 ABSTARCT Three field trials were established in early March 2004 on topsoil prepared for seeding at Kleinkopje Colliery, Optimum Colliery and Syferfontein Colliery, all situated on the Mpumalanga Highveld of South Africa. Cynodon dactylon , Themeda triandra , and Hyparrhenia hirta plugs were established in plots and were treated with and without fertilizer. Field measurement of survivorship, cover, and biomass production, were taken until July 2007. Acacia sieberana was also established and was evaluated for survivability, height and basal diameter. The results indicate that Cynodon dactylon out-performed the Themeda triandra and Hyparrhenia hirta , achieving 100% survivability and cover at all sites by 2007, regardless of fertilizer addition. Trees were able to establish at Kleinkopje Colliery attaining 97% survivability by the end of the trial, but performed poorly at Optimum Colliery and Syferfontein Colliery. Establishing plugs as a vegetative option on mined land could be used when slopes for a planter machine is too steep, and in establishing buffers against pasture grass intrusion into ecologically sensitive areas. 2 TABLE OF CONTENTS ABSTARCT .......................................................................................................................i TABLE OF CONTENTS .....................................................................................................ii CHAPTER 1 LITERATUREREVIEW …………………………………………………………………………………………………1 1.1 INTRODUCTION……………………………………………………………………………………………..1 1.2 OPENCAST MINING AND REHABILITATION METHOD…………………………………….2 1.3 SOIL COMPACTION………………………………………………………………………………………..3 1.4 SOIL AMELIORANTS………………………………….……………………………………………………4 CHAPTER 2 MATERILAS AND METHOD.. ……………………………………………………………………………………..5 2.1 EXPERIMENTAL LAYOUT………………………………………………………………………………..5 2.1.1 SITE DESCRIPTION………………………………………………………………………………5 2.1.1.1 KLEINKOPJE COLLIERY…………………………………………………………….5 2.1.1.2 OPTIMUM COLLIERY………………………………………………………………5 2.1.1.3 SYFERFONTEIN COLLIERY……………………………………………………….6 2.2 EXPERIMENTAL DESIGN…………………………………………………………………………………6 2.2.1 TRIAL ESTABLISHMENT………………………………………………………………………6 2.2.2 SPECIES………………………………………………………………………………………………8 2.3 TRIAL SETUP………………………………………………………………………………………………….8 2.3.1 PLANTING………………………………………………………………………………………….8 2.3.2 FERTILIZER APPLICATION…………………………………………………………………..8 MAINTENANCE……………………………………………………………………………………………..9 2.4 FIELD MEASUREMENTS……………………………………………………………………………….10 2.4.1 SURVIVORSHIP…………………………………………………………………………………10 2.4.2 COVER……………………………………………………………………………………………..10 2.4.3 BIOMASS……………………………………………...............................................11 2.4.4 TREE SURVIVORSHIP………………………………………………………………………..12 2.4.5 TREE HEIGHT……………………………………………………………………………………12 2.4.6 TREE BASAL COVER………………………………………………………………………….13 CHAPTER 3 RESULTS ………………………………………………………………………………………………………………….14 3.1 KLEINKOPJE COLLIERY………………………………………………………………………………….14 3.1.1 SURVIVORSHIP…………………………………………………………………………………14 3.1.2 COVER……………………………………………………………………………………………..15 3.1.3 BIOMASS…………………………………….…………………………………………………..16 3.1.4 TREE SURVIVORSHIP…………………………………………..……………………………17 3.1.5 TREE HEIGHT……………………………………………………………..…………………….17 3.1.6 TREE BASAL DIAMETER…………………………………………………….………………17 3.2 OPTIMUM COLLIERY……………………………………………………………………………………20 3 3.2.1 SURVIVORSHIP…………………………………………………………………………………20 3.2.2 COVER……………………………………………………………………………………………..21 3.2.3 BIOMASS………………………………………………………………………………………….22 3.2.4 TREE SURVIVORSHIP………………………………………………………………………..23 3.2.5 TREE HEIGHT DIAMETER………………………………………………………………….23 3.3 SYFERFONTEIN COLLIERY…………………………………………………………………….………24 3.3.1 SURVIVORSHIP…………………………………………………………………………………24 3.3.2 COVER……………………………………………………………………………………………..25 3.3.3 BIOMASS………………………………………………………………………………………….26 3.3.4 TREE SURVIVORSHIP…………………………………………………………................26 3.3.5 TREE HEIGHT……………………………………………………………………………………27 3.3.6 TREE BASAL DIAMETER…………………………………………………………………….27 CHAPTER 4 DISCUSSION AND CONCLUSIONS ……………………………………………………………………………28 4.1 SURVIVORSHIP…………………………………………………………………………………………….28 4.2 COVER…………………………………………………………………………………………………………30 4.3 BIOMASS……………………………………………………………………………………………….......31 4.4 TREE DATA…………………………………………………………………………………………………..31 4.5 RECOMMENDATIONS………………………………………………………………………………….33 CHAPTER 5 REFERNCES ………………………………………………………………………………………………………...……3 4 4 CHAPTER 1 LITERATURE REVIEW 1.1 Introduction Coal is the world’s most abundant and widely distributed fossil fuel and it remains the primary energy source for several countries world-wide. In South Africa, coal mining makes a significant contribution to economic activity, development of sustainable job opportunities and foreign exchange earnings. The coal mining sector contributes 1.8% the South Africa’s GDP. Coal extraction is essentially mined by two methods, namely underground and opencast method. Unfortunately, these are very destructive processes, and the environmental implications associated with this very serious. Unfortunately, highly potential agricultural lands, ecologically sensitive environments and surrounds are compromised for development, often resulting in loss of ecosystem value. A large portion of coal reserves and operation on the Eastern Highveld is situated in the heart of the South African grassland biome. On a global scale, this biome is considered to be one of the most devastated, and the South African grassland biome has been identified as critically endangered (Olsen and Dinerstein, 1998). In South Africa, the grassland biome covers an area of approximately 349 174 km 2 (Neke and Du Plessis, 2004). Approximately 100 000 ha has already been transformed or destroyed by opencast and underground mining on the Eastern Highveld of South Africa (Neke and Du Plessis, 2004). According to Neke and Du Plessis (2004), this could increase to 325 081 ha with the amount economically mineable coal available in the area. By law (Minerals and Petroleum Resources Act of 2002; National Environmental Management Act) opencast mines have to be rehabilitated and the post mining landscape returned to a sustainable land use. Although the objective of most 5 rehabilitation programs aim to restore land to its pre-mining agricultural land capability (Mentis, 2006) by establishing a pasture with fertilizer-responsive grass species on topsoil replaced topsoil. These pastures are made productive through defoliation management and fertilizer additions. After a few years, reversion to native grassland is opted for by withdrawing fertilizer application and applying defoliation management. However, this is a very slow process of secondary succession and often pre-mining ecological status is not achieved (Mentis, 2006). 1.2 Opencast Mining and Rehabilitation Method The Vryheid Formation (Ecca Group) of the Karoo Sequence, which is present on the Eastern Highveld of South Africa, attains some 140 m at the thickest point and contains a number coal seam, of which four are considered to have economic potential. Mining this coal is dependent on the economic limit of the depth of over burden above the coal seam, which could reach up to 30 m, and the thickness of the underlying coal seam. In order to access the coal, the material above the coal seam (known as burden material), is excavated and removed. Once the overburden is exposed, it is drilled, blasted and then removed. This material is placed such that it can be profiled, typically by dozer. The slope and depth of topsoil placed on the profiled burden material, ultimately determines the post mining land class capability for that area. Before the overburden is removed, topsoil is stripped and is either stockpiled or is placed on profiled overburden material. The placed topsoil is then levelled, thus creating a surface for seeding, and later vegetation establishment. The seed mix used for seeding typically comprises an annual species such as Eragrostis teff in combination with perennial species. Such species might include Chloris gayana, Cenchrus ciliaris, Cynodon dactylon, Digiteria eriantha, Eragrostis curvula, Eragrostis teff, and Medicago sativa (Mentis, 1999). The ratio of the seed 6 mix used for re-vegetation is usually specified in the mine’s Environmental Management Programme (EMP). 1.3 Soil Compaction The process by which topsoil is stripped, stockpiled and placed on regarded burden material often results in severe compaction. This is detrimental to the physical, chemical and biological properties of the soil. Consequently, these soils have lower soil aggregate stability, lower infiltration rates, reduced water holding capacity, and a greater capacity to resist root extension (Chapman et al , 1994), all of which inhibit the potential for plant growth and establishment on the rehabilitated soil. The major cause of soil compaction is trafficking of machinery on re-placed soil. This is further exacerbated by settling under gravity and (Haigh, 2000). As a consequence of this the particle-to-particle contact within the soil increases and the percentage of macro pores decreases (Haigh, 2000). This affects nutrient availability with de- nitrification a result of anaerobic conditions (Davies et al , 1995). Because of these changes, the soil becomes a less favourable environment for soil organisms reducing growth of surface vegetation (Haigh, 2000). The soil
Load more

Recommended publications
  • Role of Wild Leguminous Plants in Grasslands Management in Forest Ecosystem of Protected Areas of Madhya Pradesh State
    Vol-6 Issue-2 2020 IJARIIE-ISSN(O)-2395-4396 Role of wild leguminous plants in grasslands management in forest ecosystem of Protected Areas of Madhya Pradesh State Muratkar G. D. , Kokate U. R G. D. Muratkar Department of Environmental Science , Arts , Science and Commerce college Chikhaldara , District Amravati 444807 U. R. Kokate Department of Botany , Arts , Science and Commerce college Chikhaldara , District Amravati 444807 ABSTRACT Grasslands in melghat forest are of annual , taller type with course grasses. The dominant grasses are Themeda quadrivalvis , Heteropogon contortus , Apluda mutica , Chloris barbata . The soil is murmi red with low water holding capacity , in some parts the soil diversity observed black , red soil with clay , silt , sand and loam. The grasses are annual and very few are perennials like Dicanthium annulatum , Dicanthium caricosum , Cynodon barberi , Bothrichloa bladhii. The palatability of th grasses depends upon the soil nutrients , chemicals. The soil in which the wild leguminous plants like Vigna trilobata , Phaseolus radiate , Glycine max , Rhyncosia minima shows the more distribution of wild leguminous plants the soil is with more nitrogenous content due to biological nitrogen fixation and the soil shows the effects on fodder value of the grasses. Keywords : Grasslands Protected Areas , palatable grasses , soil fertility , Wild leguminous plants Introduction Madhya Pradesh is one of those promising states in India.Whether it's Bandhavgarh or Kanha or Pench, each and every national park is far from the civilization and has a rustic charm of its own. Remarkable flora and fauna of these nine National Parks is matched by scenic landscapes along with the incredible diversity.
    [Show full text]
  • A Preliminary Phytolith Reference Collection for the Mountains of Dhufar, Oman
    The use of phytoliths as a proxy for distinguishing ecological communities: A preliminary phytolith reference collection for the mountains of Dhufar, Oman Undergraduate Research Thesis Presented in Partial Fulfillment of the Requirements for Graduation “with Honors Research Distinction in Evolution and Ecology” in the Undergraduate Colleges of The Ohio State University by Drew Arbogast The Ohio State University May 2019 Project Co-Advisors: Professor Ian Hamilton, Department of Evolution, Ecology, and Organismal Biology Professor Joy McCorriston, Department of Anthropology 2 Table of Contents Page List of Tables...................................................................................................................................3 List of Figures..................................................................................................................................4 Abstract............................................................................................................................................5 Introduction......................................................................................................................................6 Background......................................................................................................................................7 Materials and Methods...................................................................................................................11 Results............................................................................................................................................18
    [Show full text]
  • Flora of China 22: 633–637. 2006. 213. THEMEDA Forsskål, Fl. Aegypt
    Flora of China 22: 633–637. 2006. 213. THEMEDA Forsskål, Fl. Aegypt.-Arab. 178. 1775. 菅属 jian shu Chen Shouliang (陈守良); Sylvia M. Phillips Anthistiria Linnaeus f. Perennial or annual, often coarse. Culms tufted. Leaf sheaths keeled; leaf blades linear; ligule short, membranous or papery. Inflorescence a leafy compound panicle composed of short racemes; each raceme on a short peduncle subtended by a sheathing spatheole, loosely arranged or gathered into fan-shaped spathate fascicles. Raceme comprising 2 pairs of large sessile homogamous spikelets at base forming an involucre, with 1–2(–5) fertile pairs above and a terminal triad, these usually deciduous, rarely raceme shed as a whole; internodes and pedicels linear. Sessile spikelet subterete or dorsally compressed; callus mostly acute to pungent, sometimes obtuse, bearded; lower glume usually leathery, margins rounded, incurving, keeled only near apex, obtuse; upper glume awnless; lower floret reduced to a hyaline lemma; upper lemma stipitiform, entire, passing into a geniculate awn with pubescent column, occasionally awnless. Pedicelled spikelet mostly larger than sessile, narrowly lanceolate, resembling homogamous; callus slender, pedicel-like; true pedicel reduced. x = 10. Twenty-seven species: tropical and subtropical regions of the Old World, mainly in Asia; 13 species (four endemic) in China. The number of spikelets in a raceme refers to the total of homogamous, sessile, and pedicelled spikelets. Hence racemes with seven spikelets (division 1a of the key) have only one fertile sessile spikelet and one awn. Racemes with more than one awn have more than seven spikelets. Most species of this genus are used for forage when young. 1a.
    [Show full text]
  • Cymbopogon Refractus, Is a Native, Grass, Themeda Triandra Kangaroo of Lemon Grass, Cymbopogon Citratus
    In recent years, native grasses have become increasingly popular for home gardens. Barbed Wire Grass, Cymbopogon refractus, is a native, long lived, perennial tussock grass, not dissimilar to another popular native grass, Themeda triandra Kangaroo Grass. The inflorescences (arrangement of flowers) are curious, some angled upwards, some spreading widely away from the stem and yet others reflexed downwards, so that the clusters are quite reminiscent of the barbs of a barbed wire fence, albeit without the rigidity and the sharp spines. Hence the common name Barbed Wire Grass. Barbed Wire Grass is interesting in other ways too. It may be an Australian native, widespread in eastern Australia, but it does have some famous relatives. If you crush and smell a leaf, it’s strongly aromatic, and smells of citrus, with perhaps a hint of ginger. You would be correct in guessing that it’s a very close relation of Lemon Grass, Cymbopogon citratus, the herb about which we are now so passionate, and an essential in south- east Asian cuisine. Another interesting relative is Citronella Grass, Cymbopogon nardus, a much taller grass from Indonesia. This is the source of the insect repellent (especially for mosquitoes) citronella oil. Geraniol and citronellol, the principal chemical constituents of citronella, are used in soaps and disinfectants. Barbed Wire Grass is common in Eucalyptus woodlands, and can grow on a wide range of soils of low fertility. It is also a useful fodder plant, as long as it isn’t grazed continuously. It has become naturalised on Pacific Islands, including Norfolk Island, New Caledonia, Vanuatu, Fiji, the Cook Islands, Tahiti and Hawaii.
    [Show full text]
  • Rangeland Ecophysiology - Jenesio I
    RANGE AND ANIMAL SCIENCES AND RESOURCES MANAGEMENT - Vol. I ‐ Rangeland Ecophysiology - Jenesio I. Kinyamario, Victor R. Squires RANGELAND ECOPHYSIOLOGY Jenesio I. Kinyamario University of Nairobi, School of Biological Sciences, Nairobi, Kenya Victor R. Squires University of Adelaide, Australia Keywords: C3, C4, photosynthesis, water use efficiency, nitrogen, productivity, rangeland management, crassulacean acid metabolism (CAM), physiological processes, CO2 fixation, Leaf area index (LAI), photosynthetically active radiation (PAR) Contents 1. Implications of plant physiological processes for rangeland ecosystems 1.1. Plant Level Interactions 1.2. Management Implications: 2. Photosynthesis 2.1. C3, C4 Pathways in Photosynthesis 2.2. Crassulacean Acid Metabolism (CAM) 3. Geographical and ecological distribution of different photosynthetic pathway plants 4. Comparative analysis of photosynthetic pathways 4.1. CO2 Compensation Point 4.2. Light Saturation 4.3. Light Compensation Point 4.4. Temperature Optima 4.5. Water Use Efficiency 4.6. Nitrogen Use Efficiency 4.7. Photorespiration 5. Photosynthetic capacity, quantum yield, and productivity 6. Implications for Rangeland Management 6.1. Herbivory 6.2. Carbohydrate Reserves 6.3. Drought and Overgrazing Combine to Cause Much Stress 6. 4. Climate Change 6.5. Invasive Species 6.6. Fires 7. ConclusionsUNESCO – EOLSS Glossary Bibliography SAMPLE CHAPTERS Biographical Sketches Summary Plants fix radiant energy through fixation of carbon into biomass that is consumed by animals. Therefore, the rates of carbon fixation and factors that determine these rates will determine the number of grazers a rangeland can be able to optimally carry (carrying capacity). Environmental factors that determine bioproductivity rates are ©Encyclopedia of Life Support Systems (EOLSS) RANGE AND ANIMAL SCIENCES AND RESOURCES MANAGEMENT - Vol.
    [Show full text]
  • Themeda Helferi (Panicoideae: Poaceae): a New Record for India
    Rheedea Vol. 28(1) 57–61 2018 ISSN: 0971-2313 https://dx.doi.org/10.22244/rheedea.2018.28.1.11 Themeda helferi (Panicoideae: Poaceae): A new record for India Anil Kumar, M. 1, Sreenath, A.1, Anjaneyulu, P.1, Saravanan, S.2 and B. Ravi Prasad Rao1* 1Biodiversity Conservation Division, Department of Botany, Sri Krishnadevaraya University, Ananthapur, Andhra Pradesh - 515 003, India. 2Conservator of Forests & Field Director, APFD-PTC, Srisailam, Andhra Pradesh, India. E-mail: [email protected] Abstract Themeda helferi Hack. (Panicoideae: Poaceae) collected from the forests of Prakasam and Vishakapatnam districts of Andhra Pradesh, India, is being reported as a new record to India. A full description, notes, illustration, photographs and a distribution map along with comparative analysis with allied species, T. quadrivalvis (L.) Kuntze are provided. Keywords: Andhra Pradesh, India, new record, Poaceae, Panicoideae, Themeda helferi, Vishakapatnam Introduction The genus Themeda Forssk. Comprising c. 29 is followed by subsequent authors (Karthikeyan et species is distributed in Africa, temperate and al., 1989; Moulik, 1997; Pandey & Diwakar, 2008; tropical Asia, Australia, Pacific, North and South Murugan et al., 2016). It may be noted that Helfer’s America (Clayton et al., 2006; Veldkamp, 2016). collections from Tenasserim (Myanmar) are mixed The genus is represented by 20 species (Bor, up with his collections from Andamans (India) 1960, Karthikeyan et al., 1989, Kabeer & Nair, as viewed by Thothathri (1977) and Mathew and 2009, Chorghe et al., 2016) in India. Of which, six Abraham (2001). Due to accidental death of J. W. are endemic, viz., Themeda mooneyii Bor (Andhra Helfer, the collections were mixed up and these Pradesh and Oidisha), T.
    [Show full text]
  • Lober, Angela Brush by Brush, Fernbrook Gallery, Kurrajong Heights, 2009 Royal Horticultural Society, London, 2012 B
    Lober, Angela Brush by Brush, Fernbrook Gallery, Kurrajong Heights, 2009 Royal Horticultural Society, London, 2012 b. Sydney, New South Wales, Australia The Art of Botanical Illustration, 12th Biennial Exhibition Residence: Australia Presented by the Friends of the Royal Botanic Gardens Email: [email protected] Melbourne, Domain House, Royal Botanic Gardens Melbourne, South Yarra, 2014 Education Florilegium: Sydney’s Painted Garden, Sydney Living Museums, Bachelor of Landscape Architecture, University of New South Museum of Sydney, Sydney, 2016 Wales, Sydney, 1985–1990 Post Graduate Diploma, Visual Art (Plant and Wildlife Honors/Awards Illustration), University of Newcastle, Callaghan, Silver-Gilt Grenfell Medal, Royal Horticultural Society, 2012 1994–1995 Celia Rosser Medal, The Art of Botanical Illustration, 2014 Career Collections Landscape Architect, Department of Housing, Sydney, Collection of Alisa and Isaac M. Sutton 1990–1999 Dr. and Mrs. Peter Kaleski Landscape architectural consultant, Sydney, 1999–2010 Florilegium, Royal Botanic Gardens Sydney Artist, Sydney, 2010– Shirley Sherwood Collection Botanic Art Teacher, Royal Botanic Gardens Sydney, Sydney, State Botanical Collection, National Herbarium of Victoria 2014– Work Reproduced In Professional Memberships Churchill, J., ed. 2015. The Royal Botanic Garden Sydney: Botanical Art Society of Australia The First 200 Years. Ultimo: Halstead Press. Florilegium Society at the Royal Botanic Gardens Sydney, Forbes, B. and M. Forbes. 1995. The Walker’s Companion Committee Member and Treasurer (Nature Company Guides). Fairfax: Time Life Books. Friends of the Royal Botanic Gardens Melbourne Glasener, E. et al. 1996. Natural Gardening (Nature Company Friends of the Royal Botanic Gardens Sydney Guides). Fairfax: Time Life Education. Stackhouse, J. 2004. Encyclopedia of Garden Design. San Artwork Media Francisco: Fog City Press.
    [Show full text]
  • FLORA of BEIJING Jinshuang Ma and Quanru Liu
    URBAN HABITATS, VOLUME 1, NUMBER 1 • ISSN 1541-7115 FLORA OF BEIJING http://www.urbanhabitats.org Jinshuang Ma and Quanru Liu Flora of Beijing: An Overview and Suggestions for Future Research* Jinshuang Ma and Quanru Liu Brooklyn Botanic Garden, 1000 Washington Avenue, Brooklyn, New York 11225; [email protected]; [email protected] nonnative, invasive, and weed species, as well as a lst Abstract This paper reviews Flora of Beijing (He, 1992), of relevant herbarium collections. We also make especially from the perspective of the standards of suggestions for future revisions of Flora of Beijing in modern urban floras of western countries. The the areas of description and taxonomy. We geography, land-use and population patterns, and recommend more detailed categorization of species vegetation of Beijing are discussed, as well as the by origin (from native to cultivated, including plants history of Flora of Beijing. The vegetation of Beijing, introduced, escaped, and naturalized from gardens which is situated in northern China, has been and parks); by scale and scope of distribution drastically altered by human activities; as a result, it (detailing from worldwide to special or unique local is no longer characterized by the pine-oak mixed distribution); by conservation ranking (using IUCN broad-leaved deciduous forests typical of the standards, for example); by habitat; and by utilization. northern temperate region. Of the native species that Finally, regarding plant treatments, we suggest remain, the following dominate: Pinus tabuliformis, improvements in the stability of nomenclature, Quercus spp., Acer spp., Koelreuteria paniculata, descriptions of taxa, and the quality and quantity of Vitex negundo var.
    [Show full text]
  • Is a Long Hygroscopic Awn an Advantage for Themeda Triandra in Drier Areas?
    bioRxiv preprint doi: https://doi.org/10.1101/2020.04.29.068049; this version posted April 30, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. Research Note Is a long hygroscopic awn an advantage for Themeda triandra in drier areas? Craig D Morris Agricultural Research Council – Animal Production (ARC-AP), c/o School of Life Sciences, University of KwaZulu-Natal, Private Bag X01, Scottsville 3209, South Africa. Email: [email protected] Abstract Themeda triandra has bigeniculate hygroscopic lemma seed awns that twist when wet and drying, thereby transporting the caryopsis across the soil surface into suitable germination microsites. The prediction that awns would be longer in drier grassland and have greater motility to enable them to move quickly and further to find scarce germination sites was tested in KwaZulu-Natal. Awns (n = 100) were collected from 16 sites across a mean annual precipitation gradient (575-1223 mm), ranging from 271-2097 m a.s.l. The daily movement of hydrated long and short awns (n = 10) across blotting paper was tracked for five days, and the rotational speed of anchored awns was measured. Awn length varied considerably (mean: 41.4-63.2 mm; sd: 3.44-8.99) but tended to increase (r = 0.426, p = 0.099) not decline, with increasing MAP. Awn length was unrelated to elevation, temperature and aridity indices. Long awns rotated at the same rate (2 min 48 sec) but moved twice as fast (46.3 vs.
    [Show full text]
  • Plant Strategies and Trait Trade-Offs Influence Trends in Competitive
    Journal of Blackwell Publishing, Ltd. Ecology 2005 Plant strategies and trait trade-offs influence trends in 93, 384–394 competitive ability along gradients of soil fertility and disturbance R.W.S. FYNN, C.D. MORRIS* and K.P. KIRKMAN Grassland Science, School of Biological and Conservation Sciences, and *Agricultural Research Council – Range and Forage Institute, University of KwaZulu-Natal, Private Bag X01, Scottsville 3209, Pietermaritzburg, South Africa Summary 1 We present evidence of trade-offs in competitive ability among five perennial C4 grass species at different levels of soil fertility and disturbance in a garden experiment in KwaZulu-Natal, South Africa. 2 Our goals were to examine plant strategy theory, using grass species that differed widely in various traits and in their response to environmental influences. More specific- ally, we wished to examine whether the importance of competition was less in low fertility or regularly disturbed environments (stressed environments) than in more fertile or undisturbed conditions, and whether species made trade-offs in competitive ability along such stress gradients. 3 The trend in the competitive ability of two species in mixture along a soil fertility gradient tended to be inversely related if one had narrow and the other broad leaves or they differed in height, providing strong evidence for trait trade-offs. Thus, a tall broad- leaved species, Panicum maximum, was the most competitive species in fertile subplots, whereas a tall narrow-leaved species, Hyparrhenia hirta, was the most competitive species in infertile subplots, but no difference in competitive ability across a fertility gradient was observed when both species in a mixture had similar traits.
    [Show full text]
  • Palatability Studies on Plants in the South-Western Orange Free State Sandveld
    12 S.-Afr. Tydskr. Plantk., 1987 , 53(1) Palatability studies on plants in the south-western Orange Free State sandveld E.R. Anderson* and B.R. Roberts Department of Primary Industries, P.O. Box 689, Rockhampton, Australia 4700 and Darling Downs Institute of Advanced Education, Toowoomb-a, Australia 4350 Accepted 13 August 1986 Studies in paddocks grazed by cattle or sheep in the sandveld of the Orange Free State indicate that grasses and karroid shrubs can be classed into three groups according to their relative palatability_ A palatability index (PI) was used to rank plant species according to their acceptability to grazing animals_ Genera with a high PI were Anthephora, Oigitaria, Panicum, Fingerhuthia, Sporobolus, Nenax and Felicia. The lowest palatability ratings were recorded for Aristida, Chrysocoma, Walafrida and Cymbopogon. The study supplies comparative data on a wide range of species which can be used in estimations of carrying capacity of grassland of varying botanical composition. The technique is low-cost and of wide application _ Studies in kampies in die sandveld van die Oranje-Vrystaat, bewei deur beeste en skape het getoon dat grasse en karoo-bossies volgens hulle relatiewe smaaklikheid in drie groepe verdeel kan word. 'n Smaaklikheidsindeks was gebruik om plantsoorte in orde van belangrikheid volgens hul aanvaarbaarheid vir weidiere, te plaas_ Genusse met 'n hoe smaaklikheidsindeks was Antephora, Oigitaria, Panicum, Fingerhuthia, Sporobolus, Nenax en Felicia. Die laagste smaaklikheidswaardes is to'egeken aan Aristida, Chrysocoma, Walafrida en Cymbopogon. Hierdie studie verskaf ook vergelykbare inligting vir 'n wye reeks plantsoorte wat in die skatting van die weidingspotensiaal van grasveld met 'n varierende spesiesamestelling, gebruik kan word.
    [Show full text]
  • 40 to 63 Were Found. in Meiosis, 6-Io Univalents Appeared at Metaphase I and Lagged at Anaphase I
    CYTOLOGICAL STUDIES IN THE GRAMINEIE D. N. SINGH and M. B. E. GODWARD Botany Department, Queen Mary College, London Received5.iv.60 THERE are still many tropical and warm temperate grasses, particularly those of Asia, Australia and Africa whose nuclear cytology has not been fully investigated and whose taxonomy is still difficult or has been subject to recent investigation. A cytological study of some of these has been begun. The investigation of special problems which have been suggested by Mr W. D. Clayton and Mr J. K. O'Byrne of the Herbarium, Kew, and Mr W. H. Foster, Samaru, Nigeria, will be published elsewhere. Root-tips of seedlings and young anthers have been used for chromosome counts in 53 species belonging to 25 genera of the family Gramine (table i).For two genera, Cal)ptochloa of Queensland, Australia and Tetrapogon of Kenya, and 29 species the counts are new. Others differ from those found by previous workers (see Darlington and Wylie, 1955). NOTESON TABLE i.ANDROPOGON: Species Hybrids Material of Andropogon gqyanus Kunth, showing morphological differences has been collected by Mr W. H. Foster from different parts of Nigeria. Morphological differences seem to be associated with polyploidy and aneuploidy. The distribution of these forms found by Mr Foster in Nigeria appears to be such that the diploid A. gajvanus Kunth (2n =20)are in the north of the country, and diploid A. tectorum Schumach and Thonn in the south. The tetraploids (2n =40)and the aneuploids (2n =35to 43) are between them. These latter are presumably hybrids. These plants are being grown on for further studies and further collections are being made in Nigeria.
    [Show full text]