## 5 Conclusions  
Based on long-term observational data from across the country, this study conducted a comprehensive analysis of the Ecosystem Vegetation Index (EVI), Gross Primary Productivity (GPP), and soil moisture conditions. The findings reveal that ecosystem productivity, as indicated by EVI and GPP, shows clear spatial clustering and positive long-term trends nationwide. Specifically, the most significant increases in EVI and GPP were observed in humid regions, while arid regions exhibited relatively slower growth. This highlights the overall enhancement of ecosystem productivity in China, particularly in humid areas. Across various land cover types, both EVI and GPP demonstrated positive inter-annual variation trends, further confirming the gradual strengthening of ecosystem productivity. The spatial correlation of EVI in China is generally strong, characterized by low-low (L-L) clusters in the north and high-high (H-H) clusters in the south. Low-high (L-H) clusters are concentrated in the Huaihai Plain, southwestern rivers, and the Pearl River Basin, while high-low (H-L) clusters are scattered along the east coast. The spatial correlation of GPP is more pronounced in the southern and northeastern regions, exhibiting L-L clusters in the northeast, L-H clusters in the Yangtze River Basin, and H-H clusters in the south. H-L clusters are dispersed in the downstream area of the Yangtze River. Both EVI and GPP show a significant tendency for spatial aggregation of high values. Specifically, the distribution of EVI hotspots and coldspots exhibits clear polarization, with high-value areas predominantly located in the southern part of the study area and low-value areas mainly distributed in the central and western regions. For GPP, hotspots and coldspots also display distinct polarization, with high-value areas concentrated in the southern part and low-value areas concentrated in the northeastern region. Notably, a low-value aggregation is observed in the Yangtze River Delta region. In distinct climatic zones, the correlation between EVI and GPP with soil moisture shows significant variation. In arid and semi-humid regions, a pronounced correlation exists between specific soil moisture depths and both EVI and GPP. However, this correlation is not significant in humid regions. When examining different land cover types, EVI and GPP values for croplands and grasslands exhibit a significant negative correlation with SM4, indicating that SM4 is a key constraint in these areas. Conversely, GPP in wetlands increases significantly with increasing soil moisture, highlighting contrasting ecosystem strategies. These findings suggest that wetlands benefit from high soil moisture, while croplands and grasslands may face challenges when soil moisture exceeds optimal levels. These insights are essential for understanding the impacts of climate change on China's ecosystems and for guiding ecological conservation and land management practices. In arid regions, water-saving measures should be implemented to optimize soil moisture conditions and enhance ecosystem productivity. In contrast, wetland protection strategies should focus on maintaining high soil moisture levels to support robust GPP. Future research should investigate the mechanisms underlying the interactions between soil moisture and ecosystem productivity under different climatic conditions and explore strategies to enhance ecosystem adaptability and stability through scientific management. Conceptualization, Y.L. and I.M. ; methodology, Y.L. and Z.G. ; software, Y.L., L.S. and C.L. ; validation, Y.L., J.H. and L.S. ; formal analysis, Y.L. ; investigation, M.W. ; resources, X.D. ; data curation, Y.L. ; writing--original draft preparation, Y.L. ; writing--review and editing, Y.L. ; visualization, Y.L. ; supervision, Y.Y. and R.Y. ; project administration, Y.Y. ; funding acquisition, Y.Y. All authors have read and agreed to the published version of the manuscript.