Natural & Applied Sciences

Research Papers/Topics Natural & Applied Sciences

Carbon sequestration on the subtropical dunes of South Africa: a comparison between native regenerating ecosystems and exotic plantations

Abstract: Rehabilitation and revegetation of mined coastal sand dunes on the east coast of South Africa makes sense. It recovers ecosystem services such as carbon sequestration. The outcome of rehabilitation, which covers a third of the mined area, is a secondary coastal dune forest similar to the forests in the region. The aim of revegetation, on the other hand, is to establish Casuarina equisetifolia J.R.Forst.&G.Forst. plantations on the remaining two thirds of the mined area, for the sma...

Species composition and larval instar population structure of Scarabaeids in forestry in the Natal Midlands

Abstract: White grub is the common name of most scarabaeid larvae and some are considered ! as grubs of economic importance to agricultural crops. Expansion of forestry into previous croplands has resulted in some pests of previous agricultural crops becoming important in forestry. Field trials planted over three seasons, determined the mortality factors influencing the establishment of commercial eucalypt and black wattle plantations in the Natal Midlands. White grubs had the highest pest s...

Evaluation of the floral rewards of Aloe greatheadii var davyana (Asphodelaceae), the most important indigenous South African bee plant

Abstract: The most important indigenous bee plant in South Africa is the winter flowering Aloe greatheadii var davyana, with a widespread distribution across the summer rainfall region. Beekeepers commonly move their hives to the "aloe fields" during winter, using the strong pollen and nectar flow for colony growth, queen rearing and honey production. In spite of its importance for the bee industry, no complete pollen analysis is available and, except for the popular bee literature, little i...

The response of biological communities to spatial and temporal changes in a regenerating coastal dune forest along the north-east coast of South Africa

Abstract: Ecological restoration that aims to reinstate indigenous processes may be constrained by regional and local conditions, especially those that drive dispersal and colonisation. Local conditions can be managed, while regional conditions cannot. The management of costly rehabilitation programmes is considered best practice when scientifically informed. My thesis documents the responses of biological communities to a range of local conditions developing in coastal dune habitats in resp...

The influence of savannah elephants on vegetation: a case study in the Tembe Elephant Park, South Africa

Abstract: Most elephants in South Africa live in enclosed areas such as the Tembe Elephant Park in Maputaland. The Park also protects sand forest. This can create a conflict of interest as elephants may influence species typical of these forests. To assess the effects that elephants may have for vegetation, I compare variables of similar plant communities inside and outside the Park. I then compared the space and landscape utilization of elephants living in the Park with those of free-rangin...

The ecology of southern African wild silk moths (Gonometa species, Lepidoptera: Lasiocampidae): consequences for their sustainable use

Abstract: The pupal cocoons of two southern African wild silkmoth species, Gonometa postica and G. rufobrunnea (Lepidoptera: Lasiocampidae), are composed of high quality silk and have potential as a commercially viable resource. However, limited ecological research has been done on these species, and their population dynamics is especially poorly known. A steady and predictable supply of cocoons is paramount to the economic sustainability of a wild silk industry. There is thus an urgent need...

The demography of a fragmented population of the savanna elephant (Loxodonta africana Blumenbach) in Maputaland

Abstract: The savanna elephant is a flagship species for conservation in Maputaland, a biologically diverse centre of endemism. At present Maputaland’s elephants are fragmented into two sub-populations, those confined to the Tembe Elephant Park (TEP) and those roaming across the Maputo Elephant Reserve (MER) and along the Futi Corridor. Fragmentation may have affected the sub-populations by skewing age and sex ratios, decreasing survival, isolating the sub-populations, and restricting land...

Systematics of the Hersiliidae (Araneae) of the Afrotropical Region

Abstract: The Hersiliidae of the Afrotropical Region is revised and the phylogenetic positions of taxa within the family cladistically analysed. The following genera have been newly erected: Tyrotama gen. nov. for Tama arida and seven additional species, and Prima gen. nov. for P. ansieae spec. nov. and one additional species. The genera Murricia Simon and Neotama Baehr&Baehr are recorded for the first time from the Afrotropical Region. All valid species are redescribed. The following 20 spe...

An evaluation of southern Africa's elephant sub-populations as a metapopulation

Abstract: Elephant management traditionally centers on reducing ecological impact and human-elephant conflict by controlling numbers. However, such an approach only deals with symptoms, and ignores the causes of the problem. Planning for cases when a species is a nuisance in some areas, but threatened in others, could benefit from the application of metapopulation theory. The theory offers a framework that is elegant, and have ecological as well as political appeal. Applying classic metapopu...

The distribution, movements and abundance of Heaviside's dolphins in the nearshore waters of the Western Cape, South Africa

Abstract: Heaviside's dolphin (Cephalorhynchus heavisidii) is a poorly studied coastal delphinid with a limited inshore distribution off the west coast of southern Africa where it is sympatric with the similar sized dusky dolphin (Lagenorhynchus obscurus). It is exposed to an unknown level of bycatch particularly in near-shore set-net fisheries and is also potentially impacted by the growing boat-based whale watching industry in South Africa. In this thesis I describe the results of a study ...

The reproductive biology of the solitary Cape mole-rat, Georychus capensis and the social Natal mole-rat, Cryptomys hottentotus natalensis (Rodentia : Bathyergidae)

Abstract: The seasonality of wild caught Cape mole-rats was investigated, focusing on endocrine, neuroendocrine and neuroanatomical parameters. The Cape mole-rat reproduces only during the winter rainfall period of the western Cape Province. Interestingly, the gonadal steroid hormones do not show any significant seasonal patterns in either males or females. In addition, the pituitary does not exhibit a reduced sensitivity to GnRH stimulation during the non-breeding season in either sex. More...

The habitat and feeding ecology of the klipspringer Oreotragus Oreotragus (Zimmermann, 1973) in two areas of the Cape Province

Abstract: The study investigates the habitat preferences and ecological adaptations of the klipspringer in the Namaqualand and the southern Cape mountains. Klipspringer social organisation was found· to consist of a monogamously mated pair defending a territory which varies in size according to rainfall. The pair bond is very strong and role differentiation occurs, with the male spending more time than the female in anti-predator vigilance. Anatomical and physiological adaptations include a...


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