摘要
Danjiangkou Reservoir is water source of Middle Route Project of the South-to-North Water Diversion(SNWD)Project,research on the dynamic changes in vegetation cover and its influencing factors is of great significance for understanding the ecological environment of the water diversion area and formulating protection measures.In this study,the normalized difference in vegetation index(NDVI)was used to analyze the dynamic changes and influencing factors of vegetation in the upstream and downstream of Danjiangkou Dam from 1982 to 2018.The results showed that the NDVI exhibited an upward trend of 0.017 year−1(P<0.05),and that the significantly increased area was located near the valley upstream of the dam,while the significantly decreased area was mainly distributed in the basin downstream of the dam and around the central city.The comprehensive contributions of climate and human activity factors to NDVI changes were 92.03%and 7.97%,respectively.The human activities in the upstream of the dam were mainly reflected in the ecological measures such as returning farmland to forest;the human activities at the downstream of the dam were mainly reflected in urban expansion,occupation of cultivated land and forest land by construction land.
丹江口水库是南水北调中线工程的水源地,研究丹江口水库植被覆盖动态变化及其影响因素,对于了解南水北调中线工程的生态环境及制定保护措施具有重要意义。本研究采用归一化植被指数(NDVI)分析了1982-2018年丹江口大坝上下游植被的动态变化及其影响因素。研究结果表明,研究时段内NDVI呈0.017year-1的增加趋势(P<0.05),显著增加的区域位于大坝上游河谷附近,显著减少的区域主要分布在大坝下游流域和中心城区周围。气候变化和人类活动对NDVI变化的综合贡献率分别为92.03%和7.97%。大坝上游的人类活动主要体现在退耕还林等生态措施的实施,大坝下游的人类活动主要表现为城市扩张、建设用地占用耕地和林地等。
基金
This research was financially supported by National Key Research and Development Program of China(2018YFC1506500)
National Natural Science Foundation of China(41971402).
