Hidden roles of protected areas in the conservation of biodiversity and ecosystem services

Many of the current protected areas worldwide are established for the conservation of particular species of interest, yet their benefits may go beyond these species since they could also contribute to the conservation of entire biodiversity pools. In addition, they may also contribute to the provision of ecosystem services. However, these benefits are seldom evaluated or targeted for improvement. Using field and remotely sensed data, we evaluated how representative of the plant biodiversity pool and of carbon sequestration is a network of nature reserves specifically established for the conservation of a target species, the giant panda (Ailuropoda melanoleuca), an icon of biodiversity conservation. Our results show that forest structure (including tree/bamboo species composition) within the nature reserve network is representative of the forest structure across the entire study region, with the exception of forests located at lower elevations which are not well represented. In addition, of the areas of forest cover gained across the study region between 2000 and 2010 (similar to 10,700 km2) only about 15% occurred within panda reserves. Furthermore, accumulated net primary productivity (NPP) per year between 2000 and 2010 across the study region exhibited a monotonic increase, while the relative contribution of the reserve network to this accumulated NPP remained relatively constant (similar to 25.5%). This suggests that the areas inside nature reserves may be reaching their maximum forest cover and NPP levels. Therefore, despite the significant positive roles of these reserves beyond the conservation of the species of interest, further conservation actions are needed to maintain and improve the conservation of regional biodiversity pools, as well as to improve gains in forest cover and in carbon sequestration. The procedures shown in this study are easily transferable to other study regions for assessing the benefits they provide beyond the conservation of the target(s) species of interest.