NPP Variation Characteristics and Driving Factors of the Yellow River Valley in the Last Decade

Based on the data of net primary productivity(NPP),mean maximum and minimum temperature and precipitation calculated by the BEPS ecological process model, continuous monitoring of NPP changes in the Yellow River Basin from 2010 to 2020 was carried out by Sen+MK trend analysis.The driving effect of temperature and precipitation on NPP was identified with multiple correlation coefficients.The impact of human activities on NPP in the Yellow River Basin was demonstrated through the change in land cover types.According to the results, there was a slight increase in NPP in the Yellow River Basin from 2010 to 2020.NPP was significantly driven by precipitation in Inner Mongolia and the coastal areas of Shandong Province, by the mean maximum temperature at the border of Inner Mongolia with Shanxi Province and Shaanxi Province, and by the mean minimum temperature around the Qaidam Basin in Qinghai Province and the Qinling Mountains.The area with low NPP in the Yellow River Basin was significantly driven by meteorological factors, and the area with high NPP saw an increase.Influenced by human activities, vegetation types changed to boost the growth of NPP,suggesting an overall improvement of the ecological environment in the Yellow River Basin.