Contribution of climate change and human activity to vegetation recovery in Shanxi Province from 2002 to 2022

Shanxi Province has fully implemented ecological protection and restoration initiatives since 2002. Assessing the spatiotemporal variations in vegetation across Shanxi is crucial for timely adjustments to ecological construction measures and ensuring their effectiveness. Based on normalized difference vegetation index (NDVI), temperature, and precipitation data from 2002 to 2022, we employed the pixel dichotomy method, trend analysis, and multiple regression residual analysis to simulate the spatiotemporal variations of vegetation cover in all the 11 muni-cipal regions of Shanxi Province. By comparing potential NDVI with actual NDVI, we assessed the relative contributions of climate change and human activity to vegetation restoration. The results showed that vegetation coverage in different cities of Shanxi Province was mainly medium-high and high cover from 2002 to 2022, with Jincheng sho-wing the highest coverage and Shuozhou showing the lowest. Climate change and human activity together promoted rapid NDVI growth during the growing season in Shanxi Province, with a growth rate of 5.4×10^-3·a^-1. The areas with significant NDVI increase accounted for 72.1% of the total area. Within the municipalities, Lyuliang demonstrated the fastest NDVI growth rate (7.3×10^-3·a^-1). Human activity played a significant role in promoting vegetation restoration in Shanxi Province, while climate change had moderate contribution, with relative contribution rates of 76.3% and 23.7%, respectively. In Changzhi, Jincheng, and Yuncheng, the relative contribution rates of human activity exceeded 90%. Climate change notably facilitated vegetation restoration in Lyuliang. NDVI decreased signi-ficantly at the junction of Taiyuan, Lyuliang, and Jinzhong and in several city centers, slightly suppressed by climate change and moderately suppressed by human activity. The NDVI in Shanxi Province was significantly positive, and overall vegetation cover had reached a relatively high level. But, vegetation cover remained low in northern Shanxi. The relative contribution of human activity was highest in the southern region, while climate change had higher contribution in the central-western region.