Lindiwe Khoza
PhD Candidate

Supervisor: Dr Charlene Janion-Scheepers (University of Cape Town)

Co-supervisors: Dr Colleen Seymour (SANBI)

About My Research

Insects are the most diverse and dominant terrestrial group of invertebrates that have been recognized as ‘the little things that run the world’. They comprise approximately 80% of known insect species. They play an important role in the ecological functions and ecosystem services, such as pollination, decomposition and nutrient cycling. Despite their ecological importance and diversity, they remain understudied because of taxonomic impediments and lack of baseline data, particularly below-ground taxa. This is especially concerning given the ongoing loss of insect biodiversity being increasingly reported. Climate change and land use intensification are the two common anthropogenic drivers of taxonomic and functional diversity causing insects to decline. Land use directly affects habitat structure, thereby reducing insect abundance and altering community composition. Therefore, quantifying species diversity is an urgent priority to aid in conservation decisions and policy-making. This project will use molecular and morphological taxonomy to quantify the total biomass of above and belowground invertebrates; identify indicator taxa and assess how these differ with land-use (grazing) and climatic variables. Lastly, the study will assess the effect of soil fauna on the decomposition rate between pristine and disturbed (grazing) sites.

This study will be conducted in five different protected areas: Cape Point Nature National Park, Kogelberg Nature Reserve, Potberg Nature Reserve, Agulhas National Park, and Grootbos Nature Reserve and the surrounding grazing farms. Sampling will be done in two seasons (Summer and Spring) using various sampling methods, which include pitfall traps, pan traps, malaise traps, and soil cores for Tullgren extractions. These samples will be analysed using DNA metabarcoding in collaboration with BIOSCAN.

This research will provide baseline data on below and above-ground species diversity in different contexts, to contribute to an efficient long-term monitoring system for South Africa. Understanding patterns and correlation of above and below-ground species diversity, and the mechanisms responsible for these patterns would be informative about the abundance and diversity of these faunas in different contexts (e.g. natural areas vs farmed).  This information will aid in conservation planning and form a reference point for future monitoring. Furthermore, sampled sites in this study will also give insight into how land use and climate may change biodiversity.

UNLOCKING THE SECRETS BENEATH OUR FEET

Soil Ecology & Entomology Research Group