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Soil erosion and wildfires are serious problems throughout the terrestrial ecosystems of the world. The Golden Gate Highlands National Park (GGHNP) of South Africa experiences high incidences of erosion and wildfires due to its orographic nature and expansive grassland habitats. Various conservation strategies are employed by Park Management to lessen the effects of these environmental factors, including instating regular prescribed burn regimes for grasslands and construction of rehabilitation structures in eroded localities. While the effects of fire and erosion are investigated across a variety of habitats and fauna, little attention is given to their effects on soildwelling arthropods. The overall objective was to determine the state of soil-dwelling arthropods across eroded and currently rehabilitated localities, as well as their responses to fire regimes, in the GGHNP. Chapter 2 aimed at determining the impact of prescribed burning on soil-dwelling arthropods in an Afromontane grassland habitat, by comparing assemblage patterns and responses of species richness and diversity between a single burnt and non-burnt locality. Soil arthropod assemblages were more species rich and abundant in the burnt site, with a higher number of species only observed in the burnt site overall. The study hints at fires creating a preferable niche for soil arthropods adapted to frequent fires in the fire-prone landscape. Chapter 3 attempted to identify possible indicators of erosion in the GGHNP, and to determine differences in soil-dwelling arthropod assemblages found in non-rehabilitated and rehabilitated eroded sites. IndVal results indicated a single strong indicator species, the mite Speleorchestes meyerae Theron and Ryke, 1969, relevant to non-rehabilitated sites, suggesting that soil arthropods show potential use in grading changes in soils of the GGHNP. Statistical modelling identified phosphorus as having a significant negative correlation on species richness in both rehabi, Afromontane Research Unit (ARU), University of the Free State (UFS), National Research Foundation (NRF)

Smaller, isolated shrubland patches are often overlooked in the context of their ecosystem functions and potential for conserving biodiversity, particularly in relation to small scale areas of diversity importance within a specific conservation area. The mountainous Golden Gate Highlands National Park (GGHNP) possesses a number of these smaller, isolated shrubland patches, providing several habitat types over a relatively small geographical area. While these shrubland patches have been acknowledged as areas of possible significance in the GGHNP, information on arthropod assemblages in these patches remains limited. This thesis investigates arthropod assemblages in these smaller shrubland patches, in response to various environmental factors, and provides a preliminary view of the current state of gene flow among five ubiquitous spider species. Three aims were selected to investigate environmental factors and their influence on arthropod assemblages, while a fourth addressed gene flow and genetic diversity of spider species. In Chapter 2, we evaluate the effect of elevation and vertical stratification on arthropod species diversities and assemblages in shrubland patches present in the GGHNP. The results indicated differing environmental pressures between and within the sampled sites brought about by elevation and stratification. However, due to the relatively short elevational range and high heterogeneity of the localities, it is not conclusive as to whether elevation was the only factor responsible for differences in population diversities across the sites. Contrastingly, vertical habitat stratification influenced arthropod assemblage richness and composition despite the small vertical distance between strata. The study suggests that multiple contributing factors, together with stratification, affect arthropod assemblages. Investigations into seasonal variation and temporal change on arthropod populations may provide insight into the protective nature of smaller shr, Afromontane Research Unit (ARU), Masonic Charitable Foundation