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1	Vegetation distribution predicting in Laonong River basin with Indicator Kriging Li, Yi-di 27 August 2007 (has links) To overcome the limit of topography and manpower, vegetation prediction is an important method in vegetation mapping. There can be used in model prediction that concern about environment factor or in data interpolation that only consider about spatial distribution. In this research, indicator kriging was used to predict the spatial distribution of the vegetation of Laonong river basin. The distributions of associations were combined from the species in these associations which had been selected by Cluster analyst and TWINSPAN. Indicator kriging used presence/absence data to calculate the distribution pattern of these species, and the each species predicted raster had its own distinctly distribution. The distribution pattern of associations were related to species distribution directly. The stability of prediction pattern were evaluated by jackknife method. All standard errors of the prediction were under 0.01, with no significant difference in 4 different sampling measures. indicator kriging vegetation distribution vegetation prediction
2	Geomorphology of a portion of Mariepskop, South Africa Beeslaar, Salome January 2013 (has links) Hillslopes usually have high heterogeneity in terms of landscape processes. Interactions occur between geology, geomorphological processes, and vegetation distribution on a hillslope. This study was undertaken to assess the processes and interactions of geology, regolith production, geomorphological processes, channel formation and how these are influenced by the vegetation on a portion of Mariepskop. Mariepskop forms part of the Drakensberg Escarpment, but is a separate hillslope within the Mpumalanga Province. A north-eastern portion of the Mariepskop forms the study site, with a drainage line located within the site. Deciduous bush covers most of the study site, and grassland patches occur on the southern parts of the study site. Quartz-feldspar-biotite gneiss dominates most of the area with the cliff and higher parts consisting of feldspar-rich schist. Three site visits were undertaken where bedrock geology, weathering, soil formation, erosion, mass movement processes and the drainage channel were assessed. Maps of these processes as well as slope profiling and plan forms were compiled. According to the results, Mariepskop shows heterogeneous processes both laterally and vertically, with various degrees of interactions taking place. Underlying geology, mass movements on higher altitudes, and soil creep on lower altitudes occur on both the northern and southern parts. Processes mainly occurring on the northern part are rockfall from drainage channel incision, weathering, rill erosion and fluvial erosion within the drainage channel. Main processes on the southern part are mass movement in term form of slumping/debris flow, and erosion, in particular rainsplash and overland flow. Soil is deeper on northern part than on southern part of the study site. Geomorphological processes interact with the vegetation distribution over the study area. Grassland patches on the southern part of the study site are mainly due to slumping/debris flow, rainsplash erosion, convexity of the plan form (therefore no valleys) and oxidic soils occurrence. Similar geomorphological processes will probably influence grassland patches over the rest of Mariepskop. / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Geography, Geoinformatics and Meteorology / unrestricted Landscape Hillslopes Vegetation distribution on a hillslope Drakensberg Escarpment Mariepskop South Africa UCTD
3	Investigation of the Determinants of African Savanna Vegetation Distribution: A Case Study from the Lower Omo Basin, Ethiopia Schloeder, Catherine A. 01 May 1999 (has links) The Ethiopian Wildlife Conservation Organization has little information on the lll extent and ecological determinants of plant species composition and distribution in Omo National Park. Elsewhere, the determinants of African savanna vegetation dynamics have been the focus of numerous investigations, yet our understanding of the hierarchical nature and relative importance of any relationships remains very general. As well, our ability to derive predictions about vegetation responses is limited to extreme generalizations. African savanna landscape ecotones have received even less attention than most landscapes. In this dissertation, I test hypotheses about plant species distribution-determinant relationships in Omo National Park, a park that occurs in a landscape ecotone. Determinants investigated include rainfall and topographic-related gradients in soil moisture and edaphic conditions, and availability of soil constituents. Rainfall pattern was determined from meteorological data and multiple linear regression. Topographic attributes were measured in the field. Availability of soil constituents was determined by evaluating and using spatial interpolation models using limited soils data, and construction of surface soil maps. Hypotheses were tested using the simple and partial Mantel tests of matrix association. Results demonstrate that predictions using spatial interpolation models based on limited, coarse-scale soils data are accurate and reliable when compared with more data-intensive investigations. Results using spatial statistics indicate that the nature of the spatial pattern of perennial species associations is a monotonic spatial trend. The distribution of perennial species associations is influenced both directly or indirectly by rainfall. An indirect rainfall relationship occurs when there is variability in topography. The means of influence by the topographic-related attributes is unclear despite significant Mantel results. In the topographically invariant portion of the study area, however, exchangeable sodium and magnesium concentrations appear to indirectly influence the distribution of perennial species associations. Strength and ordering of the vegetation-determinant relationships varied depending on the type of perennial species association type being investigated. Differences in species range of tolerance and rate of change in species association, depending on association type, landforrn, and parent material differences, account for the nature of the vegetation-determinant relationships, the ordering of the determinants, and variability in responses. determinant African Savanna vegetation distribution vegetation relationships Agriculture Environmental Sciences Plant Sciences
4	Hypsometrischer Klima- und Bodenwandel in Bergregenwaldökosystemen Boliviens / Altitudinal change of climate and soils in Bolivian tropical montane rainforest ecosystems Schawe, Marcus 06 July 2005 (has links) No description available. 550 Geowissenschaften Mathematics and Computer Science Tropischer Bergregenwald montane Waldstufe hochmontane Waldstufe subalpine Waldstufe Bolivien Yungas Höhenwandel Podsolierung Hydromorphie Sesquioxide Bodenfeuchte Streufall Nährstoffdynamik kurzwellige Strahlung PPFD PET Vegetationsverbreitung. Tropical montane rainforest lower montane forest upper montane cloud forest subalpine cloud forest Bolivia Yungas altitudinal change podzolization hydromorphy sesquioxides soil water litter nutrient dynamics short wave radiation PPFD PET vegetation distribution. QDC 420: Klima und Relief Gebirgsklima {Klimageographie} QDC 440: Bestandsklima Waldklima {Klimageographie} QDH 000: Bodengeographie QDK 000: Vegetationsgeographie

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