Ecosystems services in South Africa: a research theme that can engage environmental, economic and social scientists in the development of sustainability science?

South Africa is grappling with balancing the demands placed on natural resources by economic development, especially for the poor, with the reality of severe natural resource limitations. Sustainability science is an emerging research field that seeks to find ways of resolving these conflicts to make progress towards sustainable development. Research on ecosystem services focuses on the links between ecosystems and society, and how society benefits from them. This paper introduces the concept of ecosystem services for a broad scientific readership and argues that its attendant research provides a theme that is wide enough for the engagement of a diverse range of scientific disciplines and stakeholders in the development of sustainability science. We provide an overview of published ecosystem service studies that have explicitly dealt with South Africa and found that there were large gaps in the information on these services. Only a few have been assessed and most studies focused on particular services or specific biomes or areas, notably the Cape Floristic Region. Many studies emphasized production processes (those which yield harvestable products) but several have addressed regulatory services (notably water quantity and quality), and a few have assessed cultural services. There are few estimates of monetary values and these found that ecosystem services make substantial contributions to the economy. Research shows that human activities are, directly and indirectly, contributing to a decline in the quantity and quality of these services, with major implications for people's livelihoods and wellbeing, particularly for the poor. More direct interaction and development of an interdisciplinary understanding, common language and shared values between the different domains of science are required if the potential of research on ecosystem services for the understanding of complex, socio -ecological systems and to sustainable development are to be realized.