The changes of vegetation are uncertain due to the impacts from climate change,ecological protection and restoration measures.Understanding the impacts of climatic changes on vegetation growth is essential for ecological management and the assessment of recovery measures.MODIS provides datasets with relatively fine spatial resolution of 250 m and a long time-series,with data available since 2000.Therefore,this paper considered the Huanjiang Karst of Guangxi province,China,as the case-study area for analyzing vegetation changes through the normalized difference vegetation index (NDVI) from a MODIS product (MOD09) during the period from 2000 to 2017.The extent and intensity of the influences of climatic factors,such as precipitation,air temperature,and solar shortwave radiation (SWRad),on the changes of the annually averaged NDVI,were analyzed by multiple linear regression,and the contributions from human activities were estimated by the residual trend method.The results showed that the NDVI over 87% of the vegetated area showed an increasing trend at a rate of 0.4% a~(-1),and among the main vegetation types,the forest had the fastest increasing rate in Huanjiang region from 2000 to 2017.Based on the interpolated data,the most prominent climatic changes were characterized as a decreasing temperature and increasing precipitation over the whole in the region.Among the impacts from the climatic factors,temperature and SWRad had positive impacts on the interannual changes in NDVI,while precipitation was negatively correlated with the NDVI.The strongest effect due to climatic factors was from temperature changes overall and it varied with vegetation types.The impact of changes in temperature was dominant in cropland,while in forestland and grassland the strongest effect was from SWRad.Climatic changes,however,played only a minor role with their explanation of a mere 8.5% of the variability in the NDVI.The major dominant role probably came from human activities,suggesting that greater attention in future should be focused on these vulnerable ecosystems of karst rocky desertification areas with a sub-tropical monsoon climate.