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.

Stakeholder priorities determine the impact of an alien tree invasion on ecosystem multifunctionality

“…Although the ecological impacts of Prosopis on individual ecosystem properties and services are well described, less is known about how these ecological changes affect the supply of multiple ecosystem services to local communities and how invasion impacts different stakeholder groups. As most rural Africans directly depend on multiple provisioning services for a large part of their income (Reynolds et al., 2020), we can expect differences in priorities between stakeholders based on different sources of income, for example, crop farmers and pastoralists. However, it is unknown which other ecosystem services are valued apart from those that provide direct income, and how important these are to stakeholders.…”

A chronicle of alien medicinal plants used as traditional medicine in South Africa, and their status as invasive species

“…A risk assessment of the invasive potential of the remaining species should be undertaken (as per recommendations of (Kumschick et al, 2012(Kumschick et al, , 2020Kumschick and Richardson, 2013), accompanied by application of the existing regulations governing the movement of such species. Clearly, greater public awareness of the impacts of alien weeds on South African society is needed (Byrne et al, 2020;Reynolds et al, 2020), accompanied by regulations that are widely considered to be equitable and just (Wilson et al, 2020). Given the projections for increased trade and globalisation (Faulkner et al, 2020) and the findings presented here and in other research on alien species in South African traditional medicine, it is clear that the country must move rapidly towards implementable legislation with clear goals for alien control (Lukey and Hall, 2020), which include effective prevention measures.…”

Nature‐reliant, low‐income households face the highest rates of woody‐plant encroachment in South Africa

“…To identify the municipalities most requiring interventions, we provide a targeted spatial analysis (Figure 5). Our spatial approach represents a practical way to link land degradation patterns to ES over regional scales and identify the communities that most require interventions (see Reynolds et al (2020) for a similar approach regarding invasive alien plants).…”