Vegetation dynamics and their drivers in the Haihe river basin, Northern China, 1982-2012

In this study, we quantified the vegetation changes in the Haihe river basin (HRB) and analyzed their drivers during 1982-2012 by using satellite normalized difference vegetation index (NDVI) data, observation-based climate data, satellite vegetation continuous fields (VCF) data, and soil moisture (SM) data. The results showed that the increases in NDVI was the largest in autumn (2.12 x 10(-3)), followed by growing-season (1.97 x 10(-3)), spring (1.82 x 10(-3)), annual (1.35 x 10(-3)), summer (1.15 x 10(-3)), and winter (0.32 x 10(-3)). The VCF, mean annual temperature (MAT), SM, and mean annual precipitation (MAP) determined the NDVI changes in 44.43%, 27.69%, 5.33%, and 2.01% of the HRB, respectively. In the western and southern HRB, MAT and VCF were the dominant factors, besides, SM was one of the important factors in the western HRB. Therefore, the study identified that SM, MAT, and human activities (Changes in VCF) were the main factors that determined the changes in vegetation over HRB.