Mapping the socio-ecological impacts of invasive plants in South Africa: Are poorer households with high ecosystem service use most at risk?

Abstract

It is generally suggested that invasive alien plant species (IAPS) negatively affect livelihoods. However, there is a need to find more generalisable patterns of IAPS impacts on livelihoods, which are useful for decision making at broad scales. Here we test the hypothesis that across South Africa poorer communities with high reliance on provisioning ecosystem services are more at risk from IAPS. To do so, we integrate two national-scale datasets; 1) The South African Plant Invaders Atlas, and 2) the National Census Data, which provides details on household income and selected provisioning ecosystem service use. Our analysis revealed that the potential impacts of IAPS increased as household income decreased, confirming that IAPS had greater negative effects in poorer landscapes. Furthermore, IAPS had the potential to be more impactful on selected provisioning ecosystem services where households were more reliant on them. Taken together, our results confirm that across South Africa, landscapes with poorer households and high reliance on the selected provisioning ecosystem services are likely the most negatively affected by IAPS. This novel broad-scale approach revealed landscape-scale patterns of the potential socio-ecological impacts of IAPS and will help decision makers direct resources for IAPS management to where they may be most effective.