【摘要】 受气候变化和退耕还林还草工程实施的影响,植被分布产生一定的变化,厘清气候因子与植被生长的关系,可以为生态维护与治理提供参考依据,为生态保护成效评估提供科学基础。选择环江喀斯特区,以中分辨率卫星成像光谱仪（MODIS）卫星遥感250m空间分辨率植被指数NDVI,分析2000-2017年该地区植被变化趋势,利用多元线性回归分析累积降水、温度、辐射等气候因子的影响范围和程度,以残差趋势法厘定植被变化中的人为贡献。结果表明,（1）2000-2017年,环江地区87%的地区植被年均NDVI呈现不同程度的增加趋势,增长率为0.4%a^-1;主要植被类型农田、森林、草地年均NDVI持续改善,其中森林的改善状况最好。（2）环江地区气候变化整体呈冷湿化。温度、累积降水、辐射对植被年均NDVI的影响情况不同,就环江地区而言,温度、辐射对年均NDVI表现出正影响,且温度影响最大;累积降水与年均NDVI呈负相关。（3）不同植被类型受气候因素的影响不同,在气候因素对植被年均NDVI的解释度较高的地区,农田主要受温度影响,森林和草地主要受辐射和温度的共同影响。（4）环江地区气候因素可以解释8.5%的年均NDVI的变化情况。（5）环江地区除气候因素以外的其他因素对NDVI影响更大。更多还原

【Abstract】 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.更多还原