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Showing results 161991 to 162000 of 162400

  1. Investigating the functional and adaptive significance of leaf size and shape variation in Jamesbrittenia (Scrophulariaceae (s.s). tribe Manulae) : an experimental and comparative approach
    Moore, Timothy E, 2017-11-16T07:10:00Z, University of Cape Town
    The adaptive significance of variety in leaf forms remains a mystery for many plant groups. This study aimed, using a combined experimental and comparative approach, to investigate the functional significance of leaf size and shape variation, as well as the patterns of leaf form variation in the gen ...
  2. Potential key drivers of thicket expansion in savanna
    Trisos, Christopher, 2017-11-16T07:12:01Z, University of Cape Town
    The invasion of grasslands by woody plants and their increase in savannas is a global phenomenon. There has been a lot of work on the ecology of savanna trees, but very little on the drivers of the increase of non-savanna (forest and thicket) vegetation within savannas. The swit9h from savanna to cl ...
  3. The physiological importance of small leaf sizes in the mediterranean type ecosystem vegetation of the Cape floristic region
    Yates, Megan, 2017-11-16T07:12:58Z, University of Cape Town
    Numerous "Fynbos" species of the Cape Floristic Region (CFR) have particularly fine, narrow leaves. The rates of transpiration and heat loss are partially dependent on boundary layer conductance, which is determined by leaf shape and size, surface modifications and wind speed. We expected fine-leave ...
  4. Foraging efficiencies and species" distributions : an explanation of the Hadeda ibis (Bostrychia hagedash) in relation to soil moisture
    Duckworth, Greg, 2017-11-16T07:13:50Z, University of Cape Town
    The influence of soil moisture on the foraging time needed to meet BMR (foraging efficiency) in hadedas was explored in Cape Town, South Africa. This was done by monitoring hadedas foraging and recording the prey items eaten successfully per minute on soils of different moisture. BMR was calculated ...
  5. The impacts of indigenous herbivore grazing over five years (2004 - 2008) on vegetation dynamics in four distinct vegetation types of the winter-rainfall Little Karoo
    Madden, Christine, 2017-11-16T07:14:40Z, University of Cape Town
    Vegetation in semi-arid regions is subject to change when heavily utilised by herbivores. Changes in species richness, species and growth form composition, total cover and plant palatability in response to rest (fenced) and grazing (open) treatments was investigated in Sanbona Wildlife Reserve over ...
  6. The lazy root : Will a change in the rainfall regime or increased anthropogenic nitrogen result in an alteration in the competitive balance between trees and grassed in a semi-arid South Africa savanna?
    Bell, Wesley Drummond, 2017-11-16T07:15:24Z, University of Cape Town
    In an attempt to determine why trees and grasses are able to coexist in savannas, Walter (1971) first proposed the root niche separation model for savannas which suggests that trees and grasses have differential access to water due to spatial differences in their rooting profiles. Subsequent studies ...
  7. Nested clade analysis of geographic structure in the morphologically variable Themeda triandra in South Africa
    Oatley, Graeme, 2017-11-16T07:25:13Z, University of Cape Town
    The use of phylogeography in plant systems has been on the increase in recent years with the use of chloroplast DNA to detect sufficient intraspecific variation to reach significant conclusions about plant species histories, both temporally and spatially. In this study, the geographic structure and ...
  8. Absolute values only show part of the whole : evidence of P limitation in legumes in the CFR from N:P ratios
    Duckworth, Greg, 2017-11-16T07:28:26Z, University of Cape Town
    The influence of nutrient limitation in legumes and non-legumes was studied in the field, on nutrient poor and nutrient rich sites in the CFR in the western Cape of South Africa. 6 species of legume and 11 species of non-legume, along with their corresponding soils were taken for macro and micronutr ...
  9. Analytical study on the appraisal of communal land use management practices and policies towards climate resilience and sustainability in Bir-Temicha Watershed of the Upper Blue Nile Basin, Ethiopia
    Tenaw Hailu Tedela, 2017-11-16T12:40:58Z
    This study was aimed at analysing communal land use management practices and policies towards sustainability and climate resilience. The objectives of this study were to assess rainfall variability, climate change impact, adaptation practices and impediment factors for adaptation on the one hand ...
  10. Polypropylene and Polycarbonate containers have a varied effect on coagulation after haemodilution, as judged by TEGĀ® in vitro
    Roche, Anthony Michael, 2017-11-16T13:35:30Z, University of Cape Town
    The reasons for this study were multi-factorial, but mostly due to some interesting data obtained from a pilot study conducted at University College London (UCL). In that study, the coagulation effects in vitro of two hetastarch solutions were compared with two crystalloids by means of thrombelastog ...