NDVI-Based Vegetation Dynamics and Response to Climate Changes and Human Activities in Guizhou Province, China

Guizhou Province is a typical representative karst region in China, with poverty and a fragile ecology, and knowledge of vegetation dynamics and its response to climate changes and human activities can provide basic information for ecological environmental resource management. Based on MOD13Q1 NDVI remote sensing products and meteorological data, spatial-temporal variations of NDVI in Guizhou Province from 2000 to 2021 were investigated using trend analysis, a coefficient of variation and the Hurst index. Simultaneously, the response to climate change and human activities was also explored using partial correlation and residual analysis. It was concluded that, firstly, the regional average NDVI in Guizhou Province displays a significant improving trend, with a rate of 0.056/10a from 2000 to 2021. NDVI in Guizhou Province displays notable spatial heterogeneity, with high values mainly concentrated in forests and woody savanna regions in eastern and northwestern Guizhou and low values distributed in croplands and rapid urban expansion regions in western and central Guizhou. In addition, the overall spatial distribution of NDVI displays an upward trend, and the area of extreme and light significant improvement accounts for 81.0% of Guizhou total area. Secondly, the NDVI variation in Guizhou Province is relatively stable and the area of lower-to-moderate fluctuation accounts for 90.1% of Guizhou total area; meanwhile, the future trend of NDVI variation in Guizhou is largely sustainable. Thirdly, the NDVI variations in Guizhou are more strongly influenced by air temperature than precipitation; meanwhile, compared to climatic factors, human activities have a stronger impact on vegetation dynamics in Guizhou Province. Fourthly, the trend, stability, sustainability and relationship with climatic factors and human activities of NDVI variations are varied among different vegetation types. These results will provide valuable information for ecosystem restoration and environment protection in Guizhou Province.