Spatial and temporal change of fractional vegetation cover in North-western China from 2000 to 2010

Northwestern China is located at the core area of The Belt and The Road at present and it once has been an essential transportation hub of the ancient Silk Road. However, the north-western part belongs to arid and semi-arid region where water resource and vegetation cover are scarce, leading to soil erosion, desertification, and environmental degradation. So it is meaningful to study fractional vegetation cover in North-western China. Vegetation MODIS data of northwestern China from 2000 to 2010 were collected, and then, the pixel dichotomy model and simple linear regression model were applied in this research. The results were as follows. First, the fractional vegetation cover was decreasing from the margin to the middle and western part and the higher value shown in the north-east part of Inner Mongolia, the south part of Shaanxi, the north-west part of Ningxia, the south-east part of Gansu, and the north-west part of Xinjiang. Second, the overall trend of fractional vegetation cover was rising during 2000 to 2010, which is clearly shown in northern Shaanxi, south-eastern Qinghai and Gansu, and also south-western Inner Mongolia. Third, fractional vegetation cover varied differently with season changes. To be more specific, the index in spring and winter was considerably low; in contrast, the index in summer and autumn was improved dramatically.