马海绿洲区植被与地下水位埋深的定量关系

干旱区生态环境脆弱, 降水稀少, 绿洲植被的生长与地下水关系密切。运用2011 年8 月Landsat ETM + 遥感 数据计算提取归一化植被指数( NDVI) , 结合地下水位埋深观测数据, 从大尺度上定量研究鱼卡河流域下游马海绿 洲区地下水水位埋深与植被的生长关系。研究表明: 马海绿洲适宜植被生长的地下水水位埋深范围为3~ 41 5 m; 地下水位埋深为31 2 m 的区域, 植被的生长发育最好; 影响植被生长的临界地下水位为41 5 m。通过比较马海绿 洲、额济纳绿洲和银川平原植被区等三个中国典型内陆干旱区的研究结果发现, 植被与地下水位埋深的相关性有显 著的差异。 Eco lo gical env ir onment is a lw ays frag ile in the ar id areas w ith spar se precipitatio n, and v egetation g row th has a clo se relat ionship w ith g ro undwater . In this paper , based on t he calculated no rmalized difference v egetation index ( NDVI ) from the Landsat ETM+ r emo te sensing dat a in Aug ust 2011 and the o bserv ed g roundw ater depth data, the quantitat ive relationship be2 tw een gr oundwater depth and veg etatio n g rowth on the larg e scale in the Mahai Oasia ar ea dow nstr eam o f the Yuqia River w as studied. The results show ed that the vegetat ion in the M ahai Oasia area gr ow s well w ith the g ro undw ater depth o f 3~ 4. 5 m and g row s best w ith the g ro undwater depth o f 3. 2 m, and the critica l gr oundw ater depth affect ing the v egetation g rowt h is 4. 5 m. By comparing the r esults o f Mahai Oasis, Ejina Oasis, and Yinchuan v eg etatio n r eg io n, we found that the relationship be2 tw een v egetation and g roundw ater depth has significant differ ences in differ ent regions. / 十二五0 国家科技支撑计划: / 柴达木循环经济区水资源保障与生态保护研究0 ( 2012BAC09B00)