中国科学院水利部水土保持研究所机构知识库

黄河上游地区由于其特有的恶劣生态环境和较为单一的植被类型，生态系统较为脆弱。对该地区植被覆盖度(FVC)空间分布特征及其影响因素的研究有助于该地区生态保护措施的制定。使用2000~2015年MODIS1M NDVI数据计算黄河上游年最大FVC，了解空间分布状况及变化特征；同时采用了一种基于统计学原理的地理探测器模型，考虑非气候类环境因素、气候类环境因素和人类活动因素，使用相应的代理变量对黄河上游FVC空间分布的影响因素做定量研究。研究表明：①黄河上游FVC总体上以改善为主，空间分布特征变化不大；②单因子方面，降水量(q值0.669)是该地区FVC空间分布的主要影响因素，其他因子的影响作用存在区域差异；③降水分别和土壤类型、土地利用方式的交互作用(q值0.777、0.775)对研究区FVC空间分布起主导作用，土壤类型和土地利用的影响作用在一定高程、降水条件下才得以体现；④总体上，气候类环境因素>非气候类环境因素>人类活动因素，人类活动在与降水等环境因子的共同作用能够更充分地解释FVC空间分布；⑤对研究区的生态恢复应重点放在降水的充分利用和土地利用方式改进等方面。

Ecosystem was fragile in the upper Yellow River, which were affected by unique ecological environment and relatively single vegetation type. The distribution and its driving factors of fractional vegetation cover (FVC) provide a reference for local vegetation protection. In this paper, we used MODIS1M NDVI monthly data (2000-2015) to calculate the maximum FVC in the upper Yellow River and analyzed its distributions and characteristics. At the same time, we used corresponding proxy variables to study quantitatively the influencing factors of FVC, which used the geographical detector (Geodetector) model based on statistics theory, considering the topographical, geological, climate and human activities factors. The study shows that: (1) The FVC in the upper Yellow River has been improved. And the spatial distribution characteristics of FVC remained stable even if there was a slight fluctuation. (2) Within single factor，The distribution of FVC were mainly affected by the annual average precipitation. And there are regional differences in the effects of other factors, which the southwest of the study area is subject to the combined action of topography and pressure, while the variation of topographic factors in the central and northeast regions is relatively small, and the FVC is mainly subject to precipitation, humidity, land use types and soil types on the underlying surface resulted. (3) The interaction between the annual average rainfall and soil types, the annual average rainfall and land use types has the strongest power of determinant, while the soil types and land use types worked only if there was certain elevation, precipitation. (4) Overall, the important dominant driving factors in descending order were as follows: non-climatic environmental factors, climatic environment factors and human activities factors. The interaction of human activities with environmental factors such as precipitation can explain the spatial distribution of FVC more fully. (5) The ecological restoration methods in this area should focus on the full utilization of precipitation, reasonable management and control measures should be proposed based on precipitation and improvements in land use patterns.