Increasing Negative Impacts of Climatic Change and Anthropogenic Activities on Vegetation Variation on the Qinghai–Tibet Plateau during 1982–2019

Climate change, combined with ever-increasing anthropogenic activities, has had significant impacts on the vegetation of the Qinghai–Tibet Plateau (QTP). This study quantitatively analyzed the impacts of climate change and human activities on vegetation variation on the QTP from 1982 to 2019 based on AVHRR NDVI data and the residual trend method. The main results were as follows: (1) From 1982 to 2000, the vegetation of the QTP had an obvious restoration process, whereby 67.8% of vegetation coverage areas experienced an increasing trend, while it had a large range of degradation during 2001–2019, especially in the central QTP. (2) The positive effect of climate change on the vegetation of the QTP decreased, and the negative impact increased. The area of positive impact decreased from 68.54% in 1982–2000 to 47.13% in 2001–2019, while the negative-impact area increased from 31.46% to 52.87%. (3) The area negatively affected by human activities increased from 57.68% in 1982–2000 to 79.46% in 2001–2019 and was mainly concentrated in the grassland of the central QTP. The findings of this study provide a scientific basis for vegetation restoration and management in the QTP region.