Environmental & Physical Sciences

Environmental & Physical Sciences Research Papers/Topics

The potato tuber moth, Phthorimaea operculella (Zeller), in South Africa: potential control in non-refrigerated store environments

Abstract: Please read the abstract in the section 00front of this document. Also note that an abstract is provided for each chapter as well

Dynamics of the association between dung beetles (Coleoptera: Scarabaeidae) and the dog parasite Spirocerca lupi (Nematoda: Spiruromorpha: Spirocercidae)

Abstract: Spirocercosis is a canine disease caused by the nematode parasite Spirocerca lupi (Rudolphi, 1809) (Spirurida: Spirocercidae) and is a potentially fatal condition in domestic dogs (Canis familiaris). The larval life cycle of this parasite involves intermediate and paratenic (transport) hosts. Various species of coprophagous dung beetles (Scarabaeidae: Scarabaeinae) serve as the principle intermediate hosts. Despite extraordinary advances in biomedical research, it is unlikely that ...

Systematics of southern African Anostostomatidae (Orthoptera) based on morphological and molecular data

Abstract: The eight southern African King Cricket genera, namely Bochus, Borborothis, Henicus, Libanasa, Libanasidus, Nasidius, Onosandridus, and Onosandrus are redescribed from type and museum material and a key to the genera is provided. Additionally, the status of Libanasidus impicta is investigated and species characteristics confirmed. A key to the two Libanasidus species is also provided. No morphological support for these eight southern African anostostomatid genera was attained with ...

Phylogeny of the Scarabaeini (Coleoptera: Scarabaeidae)

Abstract: Please read the abstract in the section 00front of this document

Analysis of Varroa destructor infestation of southern African honeybee populations

Abstract: The discovery of the honeybee-specific ectoparasitic mite Varroa destructor in South Africa in October 1997 raised the spectre of massive honeybee colony losses as has occurred in most parts of the world where the varroa mite has been found. This was particularly concerning in Africa because of the importance of honeybees in the pollination of indigenous and commercial crops, and because of the numbers of small-scale beekeepers in Africa. The mite has now spread throughout South Af...

Termite responses to long term burning regimes in southern African savannas : patterns, processes and conservation

Abstract: Termites are considered to be major ecosystem engineers in tropical and sub-tropical environments, and fire in savanna systems is regarded as a major and necessary disturbance for the maintenance of biodiversity. However, most fire ecology studies have focused on vegetation dynamics with little attention given to other taxa, especially invertebrates. This thesis has addressed several aspects of savanna termite ecology. First, based on a review of studies examining the relationship ...

Integrated pest management of the banana weevil, Cosmopolites sordidus (Germar), in South Africa

Abstract: The banana weevil, Cosmopolites sordidus, is an economical pest of Musa, distributed to most areas where the crop is grown. The beetle larvae produce feeding tunnels in the pseudostem and rhizome, reducing bunch weight and causing toppling or snapping of plants. In developing an integrated pest management system for South Africa, specific aims of the study were to quantify the genetic diversity of the species around the world, investigate the population dynamics of the insect, dete...

Application of a multidisciplinary approach to the systematics of Acomys (Rodentia : Muridae) from northern Tanzania

Abstract: The systematic status and geographic distribution of spiny mice of the genus Acomys I. Geoffroy, 1838 in northern Tanzania is uncertain. This study assesses the systematic and geographic distribution of Acomys from northern Tanzania using a multidisciplinary approach that includes molecular, cytogenetic, traditional and geometric morphometric analyses, and classical morphology of the same individuals. The molecular analysis was based on 1140 base pairs (bp) of the mitochondrial cyt...

Soil invertebrate pests in the re-establishment of plantations in South Africa

Abstract: Please read the abstract provided for each separate chapter and the General Summary (Chapter 9) added to the section 00front

Systematics of Trogidae (Coleoptera) : new South African species, and a molecular phylogeny of the family

Abstract: At its inception, taxonomy simply provided guidelines for nomenclature. It has since developed into a science applied to problems relating to economics, conservation and even law. Taxonomy is arguably one of the most important pillars of the biological sciences, providing the framework from which all other studies are conducted. We expand this essential foundation by describing four new species of Trox in Chapter 2 of this dissertation - the first to be recorded in South Africa sin...

A systematic appraisal of the Eriophyoidea (Acari Prostigmata)

Abstract: The diversity of the Eriophyoidea is largely unknown and their systematic study mostly entails alpha-taxonomy which is critically important for these mites. Eriophyoid morphology is almost exclusively studied on slide-mounted specimens, and truly permanent specimen slides cannot be prepared and are eventually lost. Shortcomings in taxon descriptions are persistent, and too few morphological characters are available for systematic use, particularly for phylogenetic studies. The frag...

Local and regional factors influencing dung beetle assemblage structure across an environmental gradient in Botswana

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...

The influence of maternal protein intake on aspects of sex-specific foetal and neonatal development in Mastomys Natalensis

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...

The influence of supplementary food on the rodent communities of coastal sand dunes

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...

Mapping bugweed (Solanum mauritianum) infestations in Pinus patula plantations using hyperspectral imagery and support vector machines

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...


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