Spatiotemporal variations and driving mechanisms of vegetation net primary productivity in Jiangxi Province during 2001—2024

<bold>Objective</bold> Investigate the spatiotemporal dynamics of vegetation net primary productivity （NPP） and its driving mechanisms is crucial for understanding regional carbon cycling，providing scientific basis for ecological restoration，land-use optimization，and ecosystem management under climate change. <bold>Method</bold> Using Jiangxi Province’s vegetation NPP and its potential influencing factors from 2001 to 2024 as the research objects，this study employed Mann-Kendall tests，Sen’s slope estimation，and partial correlation analysis to identify trends in NPP and major climatic factors，as well as their interrelationships.Combined with partial dependence analysis from the random forest model，the gradient response characteristics of NPP to natural factors were explored.Additionally，the GeoDetector was utilized to analyze the driving effects of natural factors and human activities on NPP spatial patterns and their interactive effects. <bold>Result</bold> （1）During the study period，vegetation NPP in Jiangxi Province exhibited an overall fluctuating upward trend，with an average growth rate of 2.054 g/（m²·a）.Notably，36.29% of the total area showed very significant increases，primarily concentrated in low-elevation regions，where the average slope reached 5.224 g/（m²·a）.（2）Elevation was identified as the dominant factor influencing NPP spatial distribution（<italic>q</italic>=0.207 2），displaying the strongest sensitivity within the 0-650 m range.The explanatory power of factor interactions was generally higher than that of individual factors，with the interaction between elevation and temperature having the highest explanatory power（<italic>q</italic>=0.376 9）.（3）Temperature had a stronger impact on NPP than precipitation，with partial correlation coefficients of 0.53 and -0.27，respectively.Climatic conditions from the previous year exhibited a significant lag effect，though their influence was weaker than that of current-year climatic factors.（4）When the annual average temperature exceeds 19 ℃，the growth of NPP is inhibited；while when the annual precipitation exceeds 1 700 mm，NPP remains at a high level and tends to be stable. <bold>Conclusion</bold> From 2001 to 2024，vegetation NPP in Jiangxi Province showed an overall increasing trend but with notable spatial heterogeneity.Elevation was confirmed as the key driver determining NPP spatial differentiation，and multi-factor interactions played a significant role in explaining NPP spatial patterns.