Abstract: The taxonomic composition, structure, and diversity of current local species assemblages results from an interacting complex of historical, regional ecological and local ecological factors. Structural differences between such current species assemblages are primarily determined by changing ecological conditions across spatial gradients. These conditions may change abruptly or they may represent a gradual divergence. Across the Botswana Kalahari basin there is a gradual northeast-so...
Abstract: Captive multi-mammate mice, Mastomys natalensis, were paired and kept on one of three treatment diets (low, medium and high protein) in order to assess differential maternal investment in the sexes, and sex-specific resource allocation of offspring. The influence of maternal dietary protein content on maternal reproductive performance, sex-specific body composition of pups and pup growth from birth to weaning was determined. Mothers on the high protein diet were larger than those o...
Abstract: The present study arrived at investigating the influence of supplementary food on a developing rodent community on the coastal dune forests north of Richards Bay, South Africa. Four sites were selected for the field experiment. Each of these study sites comprised a treatment and control grid. Sunflower seeds were provided on the treatment grids and the response thereof on rodent population and community variables were measured. Each of the grids were trapped on a monthly bases as t...
Abstract: The invasive plant known as bugweed (Solanum mauritianum) is a notorious invader of forestry plantations in the eastern parts of South Africa. Not only is bugweed considered to be one of five most widespread invasive alien plant (IAP) species in the summer rainfall regions of South Africa but it is also one of the worst invasive alien plants in Africa. It forms dense infestations that not only impacts upon commercial forestry activities but also causes significant ecological and en...
Abstract: Please read the abstract in the section 00front of this document
Abstract: Please read the abstract in the section 00front of this document
Abstract: The Limpopo Province is a major tomato growing region in South Africa, producing 66% of the total annual tonnage of tomatoes. The Limpopo Province is particularly vulnerable to the impact of climate change, partly because it is exposed to extreme weather events. According to the Intergovernmental Panel on Climate Change (IPCC) Africa will be hit hardest by climate change as larger areas could be stricken by yield decreases of over 50% by the year 2020 because of an increasingly hot...
Abstract: Avermectins and milbemycins are commonly used in agro-ecosystems for the control of parasites in domestic livestock. As integral members of agro-ecosystems with importance in maintaining pasture health through dung burial behaviour, dung beetles are an excellent, non-target, bio-indicator taxon for examining potential detrimental effects of pesticide application. The current study uses the dung beetle species, Euoniticellus intermedius (Reiche), as a bio-indicator to test the relat...
Abstract: Four grids, each 3,42 ha (4 morgen) in size, were live trapped from April 1967 through May 1969 in two soil and vegetation types (black turf~ Acacia nigrescens community, and brown reddish soil: Acacia tortilis community) at Pongola, northern Zululand, to determine the effect of dieldrin coverspraying, at a dosage of 87,4 g/hectare (2,64 oz/morgen), on rodents. Low population numbers before and especially at the time of spraying made clear-cut conclusions impossible to reach. Roden...
Abstract: Protected areas (PAs) cover 12.9% of Earth’s land, while just 5.8% has strict protection for biodiversity (Earth’s variety of ecosystems, species, and genetic variation). Constraints of size and configuration, mismanagement, anthropogenic pressure, and climate change hamstring the capacity of PAs to conserve biodiversity. Increasingly, studies of biodiversity in human-modified landscapes provide an evidence base to support policies to make land outside of PAs as amenable as pos...
Abstract: Coal mining in South Africa is renowned for large scale removal of topsoil and subsoil through opencast mining. Such processes lead to an enormous amount of land degradation and thus, limit the land capability after mine closure. The removal and stockpiling of topsoil leads to adverse effects not only on the fertility of the soil but also the physical properties of the soil which greatly limit the ability of the soil to sustain plant development. Resultant mined soils have a varied...
Abstract: Surface water concentrations of inorganic nutrients and suspended particulate matter (SPM) components were examined and compared between Mtwapa and Shirazi creeks in Kenya. This was aimed at assesing the ecological situation of the two creeks and determine the influence of sewage discharge. The results obtained were further compared with those from Ramisi, an estuarine system. Mtwapa recorded higher nutrient, chlorophyll a and phytoplankton carbon concentrations than Shirazi. The t...
Abstract: Gonipterus scutellatus species complex is a cryptic species that feeds on Eucalyptus leaves. Both the adult and larval stages cause high levels of defoliation. Gonipterus sp. n. 2 is the species present in South Africa and Anaphes nitens was released as a biological control agent. However, Gonipterus spp. populations have continued to cause economic damage and various countries continue to seek additional biological control agents. This dissertation focused on understanding how nat...
This project work titled "Analysis of soil physical properties of gully erosion in Mgboko-umuoria, Obingwa L.G.A, Abia state, Nigeria. Studies the physical effects and causes of gully erosion in Mgboko-umuoria. So many physical properties were determined as causative agents of gully erosion in the study area.
Abstract: This study was conducted to assessing of selected heavy metals (Cr., Cd, Zn, Hg and Pb) accumulation in the edible portions of cabbage, tomato and onion cultivated around Wonji in eastern part of Ethiopia. The concentrations of the same heavy metals were determined in water samples collected directly from industry discharge and also three irrigation sites Varied between sampling points. Vegetable Samples were first optimized through wet digestion procedure and contents of heavy met...