Variation in Vegetation Quality of Terrestrial Ecosystems in China: Coupling Analysis Based on Remote Sensing and Typical Stations Monitoring Data.

Vegetation is the most important component of the terrestrial ecosystem. Scientific and quantitative analysis of changes in vegetation quality is of great significance to the realization of ecosystem sustainability. Based on data of remote sensing and typical station monitoring, we examined dynamic NDVI (Normalized Difference Vegetation Index) changes in typical ecosystems from 1998 to 2020. We found that about 1/3 of China's regions had significantly improved vegetation quality in the past 22 years, and 10% of the region had decreased, which indicated that China's ecological situation is continuously improving. There is a large spatial heterogeneity in the trend of NDVI changes. The NDVI of agricultural and forest stations in the north of China rose relatively slowly. The NDVI of desert stations has a significant upward trend. The large-scale implementation of ecological restoration projects had improved vegetation conditions. The NDVI of forest stations and agricultural stations in the south of China still showed growth, which already has better vegetation conditions. This research can provide theoretical support for the long-term monitoring of different ecosystem types and ecological protection in China.