Tracking the effect of climate change on ecosystem functioning using protected areas: Africa as a case study

Protected areas represent important core 'units' for in situ conservation. However, the current static system is at risk from the effects of global environmental change. This is especially true in Africa, a biodiversity-rich continent expected to be hit hard by climate change. Focusing on African protected areas that experience limited human impact (International Union for Conservation of Nature (IUCN) categories I and II), we tested three hypotheses regarding the impact of climate change on the dynamics of net primary productivity (NPP). We expected a lower annual NPP and higher seasonality in NPP in Eastern and Southern Africa; changes in NPP dynamics to coincide with changes in precipitation; no correlation between changes in NPP dynamics and human development. To test these expectations, we used the Normalised Difference Vegetation Index (NDVI) as an index of NPP. Results show that, between 1982 and 2008, an increased vegetation greenness was observed in 27% of the protected areas monitored (mostly in Western Africa), and an increased seasonality in 9% of them (mostly in Eastern and Southern Africa). Our results lend support to current expectations regarding the impacts of climate change, and demonstrate how protected areas of IUCN categories I and II could be used to track the effect of climate change on ecosystem functioning in Africa, and possibly elsewhere. The study highlights the need for a dynamic approach to conservation, where the relevance and efficiency of management actions need to be regularly evaluated. It also demonstrates that satellite-based approaches offer a cheap, verifiable way to quickly identify protected areas of concern at a global scale, supporting managers in their effort to design and apply adaptive management strategies. © 2012 Elsevier Ltd.