Abstract: Due to the influence of topography, climate and human disturbance, the dry-hot valley ecosystem of Jinsha River is severely degraded, being a typical ecologically fragile area. With the MODIS-NDVI data during 2010-2021, we investigated the spatiotemporal variations and future trends of vegetation coverage in the dry-hot valley of the Jinsha River, as well as its relationship with climate change, human activities, and altitude factors, using trend analysis, residual analysis, and partial correlation analysis. The results showed that vegetation coverage in the study area had generally increased with a rate of 0.0093 a^-1 over the last 12 years. The area with an increasing trend in vegetation coverage was larger than that with a decreasing trend. The change types of vegetation coverage were mainly low fluctuation, and future changes in vegetation coverage will be dominated by an upward trend. Vegetation coverage was weakly positively correlated with temperature and precipitation in 60.23% and 60.26% of the region, respectively, but only 3.47% and 5.08% passing the significance test. Human activities generally had positive effects on vegetation coverage. Altitude influenced vegetation coverage in the Jinsha River dry-hot valley. The proportion of low and medium-low vegetation coverage showed an increase-decrease-increase trend with increasing altitude, while the proportion of high vegetation coverage was the opposite.

Key words: vegetation coverage, dry-hot valley, trend analysis, driving force