Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 79 for “"natural vegetation"”.
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Relationships between body size, reproduction, and abundance in natural vegetation
… a relatively large plant body size. Yet, within natural, crowded vegetation, most resident species are small, and species size distributions are right-skewed at virtually all scales. I aim to provide a potential explanation for this paradox: small species are able to coexist with and outcompete …
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The natural vegetation of the Robertson Karoo : an evaluation of its conservation status
The natural vegetation of the Robertson Karoo contains many taxa and vegetation communities worthy of conservation. This thesis is concerned with aiding the future conservation of natural vegetation of the Robertson Karoo by assessing the threats to its survival and identifying priority …
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Estimating minimum thresholds of natural vegetation for the integrated management and protection of water quality in South African catchments
… have severe socio-ecological consequences. As natural vegetation acts as a sink, thus protecting water resources from diffuse pollution, the preservation of an adequate amount within catchment areas is important. However, among several pertinent questions, it is not clear (1) how much natural …
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Effects of natural vegetation, fire and alien plant invasion on bird species assemblages in mountain fynbos of the southwestern Cape Province, South Africa
… differences in plant species assemblage and vegetation structure, and of two major disturbance factors (woody alien plant infestation and fire), were investigated in Mountain Fynbos at two sites in the southwestern Cape Province, South Africa. Three associated processes were also studied. …
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Ecosystem functioning, ecosystem services and rooibos production as affected by connectivity to natural vegetation and agrochemical use in rooibos tea (Aspalathus linearis) farming
… use on ecosystem services delivered by natural vegetation, but these impacts have not been assessed for the indigenous crop Aspalathus linearis (rooibos). The study was performed on 13 sites in Nieuwoudtville and Clanwilliam. I found evidence that rooibos pollination is dependent on …
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A socio-ecological analysis of environmental change in the Kannaland Municipality of the Klein Karoo, South Africa, over the last 100 years
… systems approach to explore change in natural vegetation and land use within the Kannaland Municipality of the Klein Karoo. Repeat ground photography, historical climate and agricultural data, and in-depth, semi-structured interviews were used to assess environmental, political and …
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Ecosystem goods and services in semi-arid lanscape : an examination of the relationship between ecological processes, land-use strategies and biodiversity conservation
… to be highly dependent on the incorporation of natural vegetation and the maintenance of key ecological processes. Natural vegetation is essential for the provision of goods and services related to grazing and livestock production, with different vegetation types providing different goods and …
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Alien plant invasion on the Agulhas Plain : a detailed description of invasion patterns
… extent to which invasive alien species affect natural vegetation. It is important to classify such species based on abundance and distribution in order to determine invasion patterns and set priorities for management within a region. Such a study was adapted for the Agulhas Plain of South …
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Climate change effects on land degradation and agriculture in the Swartland, South Africa
The Swartland is a region of sparse natural vegetation, consisting of primarily dry-land crop farming. The area is particualarly sensitive to the changing Meditterranean-type climatic conditions and is characterised by undulating terrain and a history of land degradation and soil erosion. This …
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How vertebrate communities affect quality and yield of macadamia farms in Levubu, South Africa
… change with landscape and may be supported by natural vegetation. It is hence inevitable to assess them together to uncover their relative value and importance. Habitat loss and fragmentation are major threats to biodiversity and ecosystem services. Agricultural intensification can cause …
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Mapping and Modelling of Vegetation Changes in the Southern Gadarif Region, Sudan, Using Remote Sensing
… agriculture and its rapid expansion on the natural vegetation in the southern Gadarif Region. To achieve these objectives the study utilized a series of techniques. Beside the intensive use of remote sensing imagery, interviews with key informants and farmers as well as detailed field …
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Vineyard floor management in the Finger Lakes region: physiological and microbial perspectives
… (Vitis vinifera L.) vineyard, under-vine natural vegetation reduced vine canopy leaf layers and occlusion layers in one of the years compared to glyphosate maintained bare soil but there were no detectable sensory differences among wines from different under-vine floor treatments in any …
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Atmospheric deposition of combined nitrogen in the Cape Metropolitan Area: a threat to a species rich ecosystem?
… gauge levels of atmospheric N deposition to the natural vegetation of the Cape Metropolitan Area (CMA). In the first approach, bulk collectors were constructed and set up at five sites around the CMA in order to trap atmospheric deposition for chemical analysis. In the second approach, moss …
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Himalayan Blackberry (Rubus armeniacus) Effects on Fish Habitat: Impacts from Riparian Zones Inundated with Himalayan Blackberry
… a riparian zone consisting primarily of native vegetation (reference conditions) (5 sites). This thesis studied streams in the lower mainland of British Columbia near Coquitlam, Maple Ridge, and Mission to assess fish habitat quality indicators that included invertebrate drift input …
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Human-rainforest interactions in Island Southeast Asia: Holocene vegetation history in Sarawak (Malaysian Borneo) and Palawan (western Philippines)
… to examine relationships between pollen, vegetation change, and land use in the tropical environments of Island Southeast Asia over the past ~5000 years. Interpretation of fossil pollen data relies upon uniformitarian principles. Few modern pollen- vegetation studies from the region exist, …
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Effect of Hormonal and Temporal Factors on Captive Female Manatee (Trichechus Manatus Latirostris) Behavior
… provisioned food availability over the day and natural vegetation over the study period. Five manatees had estrous cycle patterns. Two individual behaviors, blowing bubbles and inverted posture, and the level of interaction were positively associated with the
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Effects of Cover Crop Treatments on Apple Trees
… rye [Lolium multiflorum]), or 3) unmanaged natural vegetation drive row plantings, with mowed vegetation blown into the tree row as mulch (mow/blow) nested variable. The legume crop cycles produced more than twice as much cover crop tissue N than grasses or natural vegetation. Soils with …
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The use of digitally interpreted satellite imagery, with special reference to topographical shadow effects, as an aid to vegetation mapping in the Hottentots Holland Mountain catchment area of the Western Cape Province
… for extracting information, relating to vegetation, from digital imagery. The effect of topographic shadow on the imagery is explained and a short discussion of mountain fynbos, the natural vegetation of the mountains of the Western Cape Province of South Africa, is included. The report …
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Monte Carlo simulation model for electromagnetic scattering from vegetation and inversion of vegetation parameters
… scattering model for microwave remote sensing of vegetation canopy is developed on the basis of Monte Carlo simulations. An accurate model of vegetation structure is essential for the calculation of scattering from vegetations, especially those with closely spaced elements in clusters. The Monte …
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The effect of supplementary nectar feeders on bird-plant mutualisms in the Cape Fynbos, South Africa
… feeders may also lure birds away from indigenous vegetation, affecting the rate of visits to bird-pollinated plants, with consequences for seed set. This study is the first to investigate the effect of nectar feeders on an African plantpollinator mutualism. Given that many plant species in the …
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