Thesis (M. Sc.)(Wildlife Management)--University of Pretoria, 2003. / Abstract in English. Includes bibliographical references.

Thesis (M.S.)--University of North Texas, Dec., 2009. / Title from title page display. Includes bibliographical references.

Thesis (Ph. D.)--Florida State University, 2005. / Advisor: Dr. Yassir A. AbdelRazig, Florida State University, College of Engineering, Dept. of Civil and Environmental Engineering Title and description from dissertation home page (viewed June 14, 2005) Document formatted into pages; contains xii, 208 pages. Includes bibliographical references.

Thesis (M. Sc.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 90-94).

Thesis (M. Sc. ) - niversity of the Western Cape, 2009. / Includes bibliographical references (leaves 72-79)

Thesis (M.U.D.)--University of Hong Kong, 1998. / Includes bibliographical references (leaves 63-65) Also available in print.

Theses (M.S.)--Marshall University, 2007. / Title from document title page. Includes abstract. Document formatted into pages: contains viii, 113 pages including illustrations and maps. Bibliography: p. 44-45.

Thesis (Ph. D.)--University of Rhode Island, 2006. / Includes bibliographical references (leaves 269-279).

In May 1994 IFAW funded the relocation of 50 elephants from the Kruger National Park to Welgevonden Private Game Reserve in the Northern Province, South Africa. Impact by the elephants on the vegetation of this reserve has since become a concern. The aim of this study was to quantify impact by the elephants on the woody vegetation by investigating vegetation and habitat use by elephant bachelor and breeding groups. This was determined by comparing resource use between sexes within seasons, and within sexes between seasons. Data were collected at two ecological scales: feeding patch scale and habitat scale. Feeding data were collected from 202 food plots, defined from 161 elephant sightings. In the dry season, when resources are often limited, no difference in feeding patch use was found between bachelor groups and breeding groups. This may suggest a lack of inter-sexual competition and could therefore suggest that the elephant population is currently below carrying capacity. Three habitat types are available to the elephants: plateau, hillslope and valley bottom. Both bachelor groups and breeding groups preferred valley bottom in comparison with habitat availability, in both seasons. When sexes were compared within seasons, in the dry season, bachelor groups used valley bottom more and breeding groups used hillslope more. / Dissertation (MSc (Zoology))--University of Pretoria, 2006. / Zoology and Entomology / unrestricted

Gold mining in South Africa resulted in vast volumes of waste material, mainly in the form of tailings material. Poor management of most of the tailings dams resulted in the release of acid mine drainage that in some cases caused soil degradation and water contamination underneath and around these sites. Although many tailings dams have been partially or completely reclaimed, their contaminated footprints pose a serious threat to the water quality of the underlying aquifers (e.g. dolomitic aquifers). This study investigated the geotechnical, mineralogical and geochemical parameters of eleven selected partially or completely reclaimed sites situated near Johannesburg. The main objective of the field and laboratory experiments was to assess the pathway of contaminant migration resulting from acid mine drainage from tailings materials through the unsaturated zone into the groundwater system. Comparing extractable contaminant concentrations with a soil standard from literature represents the environmental short-term impact. In contrast, total element concentrations in the soil compared with background values were used to describe the long-term impact or worst-case scenario. Extraction tests have shown that only a minor portion of contaminants (i.e. Co, Ni and Zn) is mobile in acidic soils. This implies that plant growth could be limited because of phytotoxic elements occurring in the topsoils, complicating rehabilitation measures. In addition, the soils often contain anomalous trace element concentrations, providing a pool for future contamination. Buffer minerals will eventually be depleted and the subsequent acidification of the subsoil, could result in the remobilization of contaminants from the subsoil into the groundwater system in the long term. It is important to understand the parameters, which control the balance between retention and mobility of contaminants in soils. Therefore a risk assessment approach would be required for all tailings dams and reclaimed sites to identify those sites, which need rehabilitation and to define the type and extent of remedial measures. Minimum rehabilitation requirements at reclaimed sites could consist of soil management measures such as liming and the addition of organic material and fertilisers to minimise the contaminant migration from the topsoil into the subsoil and groundwater as well as to provide suitable conditions for vegetation growth and future land use. Removal of remaining tailings and excavation of those portions of the soil, which are excessively contaminated, are necessary. Tailings dams which pose a high risk to the environment would require a well-engineered soil and vegetation cover to limit rainfall infiltration into the impoundment, and thus to reduce the oxidation of sulphide-bearing minerals such as pyrite. Long-term monitoring is an absolute prerequisite to ensure the success of rehabilitation, and therefore the safe use of land and water. / Thesis (PhD)--University of Pretoria, 2007. / Geology / Unrestricted