Tree cover changes in- and outside protected areas in China

Protected areas (PAs) are one of the main tools in the global conservation of biodiversity and ecosystems. This is also the case for China. However, only few studies have investigated protected areas´ efficiency in maintaining ecosystems and biodiversity. One way to investigate this is to look at tree cover changes inside the PAs and on the surrounding areas. Using MODIS Vegetation Continuous Fields we mapped tree-cover changes between 2000-2010 in- and outside PAs in China. The PAs were extracted from the World Database on Protected Areas. Our aim were to investigated the following four questions; 1) Have there been any tree cover changes inside the PAs? 2) Are any such tree cover changes inside the PAs less than in the surrounding areas (areas within 10 km from a given PA)? 3) Do tree cover changes inside and outside PAs increase with increasing general human pressures in a region? 4) Does the efficiency of the PAs depend on general human pressures in the region? We used a paired t-test to investigate if there was a significant change in tree cover between the protected areas and the 10-km zones surrounding them. There were both negative and positive tree cover changes inside the PAs, but they did not differ significantly from the tree cover change in the buffer zones. The average mean tree cover change for the PAs was 2.69 % and for the buffer zones was it 2.73 %. In addition, we link tree cover changes to the Human Influence Index and tested if there were a correlation between tree cover change and general human pressure. We did not find a significant correlation between tree cover change inside and outside PAs with increasing general human pressures. The lack of correlation could be due to the huge reforestation China has carried out the last years, mainly to stop desertification. In a further study will we investigate if there is a correlation between tree cover change and other variables, e.g. elevation and slope, inside and outside the PAs and also if HII correlates with overall tree cover change in China.Keywords: biodiversity, biogeography, conservation, China, protected areas