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Regional biogeographical patterns result from a complex combination across habitat, climate and environmental variables. Biotic and abiotic variables strongly influence the diversity and spatial distribution patterns. However, very few studies analyse the close interaction and effect of environmental variables on diversity at fine spatiotemporal scales. In this study, we evaluated the influence of soil type, vegetation cover and temperature on species diversity and functional structure of dung beetle assemblages. Dung beetle species were sampled using pitfall traps baited with cattle dung from sandy and clay soils in open woodland and closed canopy areas in Mkhuze Game Reserve, KwaZulu‐Natal, South Africa. We performed a PERMANOVA, a PERMDISP and an NMDS to analyse differences in species composition between soil and vegetation cover types. To test the effect of environmental variables on species richness and abundance, we performed a generalised least squares model. Lastly, we searched for nodes using a bipartite analysis to evaluate network's potential modularity. We collected 1439 specimens comprising 27 species and 13 genera. Species composition differed between environmental variables. Soil type was the most important driver for changes in dung beetle species composition. Species richness and abundance were influenced by the interaction between soil type and vegetation cover. The combination of microenvironmental preferences potentially influenced the dung beetle assemblage diversity and functional structure. Combining all these preferences may act as a dilution mechanism of interspecific competition in saturated habitat conditions, reducing the number of species that potentially interact and generating a modular network structure of the assemblage. [ABSTRACT FROM AUTHOR]

Studies examining changes in functional diversity and trait composition for soil arthropods are limited yet crucial for understanding the effects of land-use change. To determine whether plantation forestry drives functional homogenization of soil biota, we compared the taxonomic and functional diversity of ants and springtails between natural (indigenous forests and grasslands) and transformed (Eucalyptus plantations) biotopes. The prevalence of morphological and ecological traits in natural vs. transformed biotopes was also assessed. The study was conducted in two environmentally contrasting regions: high elevation areas with clay soils and coastal areas with sandy soils, in KwaZulu-Natal, South Africa. Surprisingly, the Eucalyptus compartments generally had similar levels of taxonomic and functional diversity as indigenous forests and/or grasslands. However, there were shifts in traits between the three biotopes, with each biotope supporting arthropods with traits suited to the environmental conditions in the biotope. Some traits were representative of the natural biotopes, and others of the plantation compartments. As a functionally diverse component of soil biodiversity is present in the plantations, it is indicative that these plantations have seemingly high levels of ecosystem stability and functioning. Arthropod traits compatible with the different environments appear to allow them to persist in high diversity across the landscape mosaic. These results suggest that enhancing landscape heterogeneity in a production landscape increases taxonomic and functional diversity of soil arthropods by creating a large-scale, spatial mosaic of complementary conditions for species with different habitat requirements. • Grassland, forest and plantations have high levels of functional soil arthropod diversity • Contrasting habitats have soil arthropods with traits suited to each habitat • High trait diversity enables soil arthropods to survive in timber systems • Agroecological systems offer opportunities for maintaining high levels of soil fauna [ABSTRACT FROM AUTHOR]

This study extended the association between hookworm transmission in KwaZulu-Natal and the sandy coastal plain by investigating the parasite's occurrence in isolated areas of sandy soils further inland. A school-based prevalence survey was carried out in selected inland sandy areas and in surrounding areas dominated by clay soils within a narrow altitudinal range of between 500 and 700 m to reduce the effect of altitude on climate-related factors (rainfall and temperature). Sandy areas situated on the coastal plain were included in the analysis for comparative purposes. Soil samples (0–50 mm depth) were collected from each locality to assess their nematode loadings and to analyse selected physical and chemical properties. Significant differences were found between the moderate prevalence of hookworm infection among children living in inland areas with sandy soils (17.3%) and the low prevalence in surrounding non-sandy areas (5.3%, P < 0.001), and between infection among children living in all inland areas (9.3%) and the high prevalence on the coastal plain (62.5%, P < 0.001). Amounts of fine and medium sand were highest in both the coastal plain soils and in inland sandy areas and these fractions showed a significant positive correlation with hookworm prevalence and nematode loadings. Clay, coarse sand and organic matter contents were highest in surrounding non-sandy soils and showed a significant negative correlation with the nematode variables. No statistically significant correlations were found with soil pH at study localities. We conclude that properties of inland sandy soils, particularly particle size distribution, correlate well with hookworm prevalence and nematode loadings and therefore provide a more suitable habitat for nematodes than surrounding non-sandy areas. These results suggest that particle size distribution of sand fractions, organic matter and clay content in the soil influence the survival of hookworm larvae and hence the parasite's transmission. [ABSTRACT FROM AUTHOR]