Identifying ecosystem service hotspots for environmental management in Durban, South Africa

Background: Despite considerable research into the importance of ecosystem services, little has been achieved in translating such research into management action. In an urban context where numerous pressures on ecosystem services exist, the identification and management of priority ecosystem services areas are vital to ensure the ongoing provision of these services. Method: To identify opportunities for securing a sustainable supply of ecosystem services for the city of Durban, this paper identifies ecosystem service priority areas, called hotspots, and assesses their spatial congruence with critical biodiversity areas (CBAs), conservation areas, the Durban Metropolitan Open Space System (D'MOSS) and land ownership categories, using spatial overlap and correlation analyses. Hotspots for 13 ecosystem services were identified and analysed, including carbon storage, nutrient retention, sediment retention, water supply and flood attenuation. Results: The study found generally weak correlations between ecosystem service hotspots and CBAs and conservation areas. On average, 30% of the 13 ecosystem services hotspots were located within terrestrial CBAs, 51% within the D'MOSS, with nominal overlaps of 0.3%, 3.9% and 5.07% within estuaries and freshwater CBAs and conservation areas, respectively. The majority of ecosystem service hotspots were located within communally (41%) or privately owned (27%) lands. Conclusion: The results indicated that substantial portions of hotspot areas lie outside of formally regulated and managed conservation areas and remain vulnerable to human impact and habitat degradation. The study identified management areas and options that could yield maximum benefits; including the need for the development of an ecosystem services management and protection strategy, the selection of areas for co-management of ecosystem service hotspots and CBAs and the need for collaborative management.