Spatiotemporal Distribution of the Impact of Climate Change and Human Activities on NDVI in China

The Normalized Difference Vegetation Index (NDVI) is a vital metric for assessing surface vegetation cover and productivity, and plays a significant role in monitoring environmental changes and ecological health. This study utilizes the Geographically Weighted Temporal Regression (GTWR) model and high-resolution remote sensing data to analyze NDVI fluctuations across mainland China from 2001 to 2020. The objectives are to elucidate the mechanisms by which climate change and human activities influence vegetation dynamics. The main findings are as follows: (1) NDVI fluctuations are significantly correlated with climatic factors such as precipitation, sunlight duration, and average temperature. These correlations reveal how climate conditions affect vegetation dynamics. (2) Human activities, particularly urban expansion, also impact NDVI changes. The study highlights how these activities contribute to variations in vegetation cover and productivity. (3) The analysis identifies distinct regional and seasonal patterns in NDVI changes, demonstrating significant spatiotemporal heterogeneity across mainland China. (4) The results enhance scientific understanding of vegetation change trends in China and provide a basis for developing targeted ecological protection measures and sustainable development policies.