Changes in Vegetation Cover and Driving Factors of Ecological Barrier in Southern Yunnan, China

Based on MODIS NDVI products from 2000 to 2020, Modified Universal Soil Loss Equation(RUSLE), Man-Kendell Trend Analysis, and GeoDetector were used to reveal the pattern of change in the vegetation cover of the ecological barriers in southern Yunnan, and clarify the driving factors of the ecological barriers in southern Yunnan caused by different natural and social factors. social factors on the vegetation cover of the ecological barrier in southern Yunnan, and clarified the driving factors of different natural and social factors on the vegetation cover of the ecological barrier in southern Yunnan. The results show that the regional ecosystem type is stable, the area of natural ecosystems consisting of forests, scrublands, grasslands and wetlands maintains the proportion of the total area of the region at more than 84.90% all year round, the vegetation cover of the study area and the counties and districts improves year by year, and the amount of soil erosion decreases steadily. From 2000 to 2010, ecosystem type, cumulative annual rainfall and surface temperature were important drivers of changes in regional vegetation cover; from 2010 to 2020, ecosystem type, surface temperature and slope were the dominant drivers, with cumulative annual rainfall being replaced by slope. The study concluded that the annual cumulative rainfall(1400-1600 mm) from 2011 to 2013 had reached a threshold for driving vegetation cover of the ecological barrier in southern Yunnan, and annual rainfall changes no longer played an important role in driving regional vegetation cover; slope, as one of the necessary ground conditions affecting plant growth, became an important driver of regional vegetation cover.