地下水和干旱指数对植被指数空间分布的联合影响:以鄂尔多斯高原为例  

Joint influences of groundwater and aridity index on the spatial distribution of vegetation index:a case study in the Ordos Plateau,China

作　　者：齐蕊[1] 王旭升[1] 万力[1] 黄金廷[2] 冯雨晴[1] 蒋小伟[1] 韩鹏飞[1] QI Rui WANG Xusheng WAN Li HUANG Jinting FENG Yuqing JIANG Xiaowei HAN Pengfei(School of Water Resources and Environment, China University of Geosciences （Beij ing） , Beijing 100083, China Xi＇an Center of Geological Survey, China Geological Survey, Xi＇an 710054, China)

机构地区：[1]中国地质大学(北京)水资源与环境学院,北京100083 [2]中国地质调查局西安地质调查中心,陕西西安710054

出　　处：《地学前缘》2017年第2期265-273,共9页Earth Science Frontiers

基　　金：国土资源部国土资源公益性行业科研专项基金项目(201311076);全国优秀博士学位论文作者专项资金项目(201457)

摘　　要：鄂尔多斯高原无定河与都思兔河之间的地段属于我国西北地区典型的干旱-半干旱过渡带,覆盖毛乌素沙地,存在大量的地下水浅埋区,为植被生长创造了有利条件。前人研究表明鄂尔多斯高原沙地植被的盖度随着地下水埋深的减小而增大,但没有充分考虑气候梯度的影响。本研究依托大量井孔调查资料建立了研究区地下水埋深的高分辨率栅格数据,与区内增强型植被指数EVI的遥感数据和气候数据进行相关分析,并建立地下水埋深与干旱指数双因素坐标系来确定区域植被指数对地下水和气候背景的联合响应。研究结果表明:干旱指数和地下水埋深的增大都会导致植被指数的概率统计值减小。干旱指数介于3~5时,地下水埋深对植被指数的影响比较显著,且地下水埋深介于1~3m最有利于高盖度植被的出现。地下水显著影响植被分布的临界埋深约为7m。这一结果改进了前人关于鄂尔多斯生态水文地质特征的认识。The region between Wuding River and Dosit River in the Ordos Plateau,China,is a typical arid to semiarid zone in Northwest China.This region is covered by the Mu Us desert,whereas shallow groundwater exists in many places,which created a favorable condition for vegetation growing.Previous studies showed that the vegetation coverage in the Ordos Plateau increased with the decrease of groundwater depth,but the impact of the climatic gradient was not soundly considered.This study establishes a high resolution grid data of groundwater depth in the study area based on a large amount of well data,with which to conduct an analysis on the correlation between the satellite enhanced vegetation index（EVI）and groundwater/climate data.A double factor coordinate system composed of groundwater depth and aridity index is developed to show the response of vegetation index at regional scale on both of the groundwater condition and climate background.Results show that both the increases of aridity index and groundwater depth will lead to the decrease of the statistical values of vegetation index of specific probabilities.When the aridity index ranges between 3-5,the vegetation index is significantly influenced by groundwater depth,and the most beneficial groundwater depth to the emergence of high coverage vegetation is 1-3m.The critical groundwater depth for significant groundwater-vegetation relationship is about 7m.The results improve the understanding of the eco-hydrogeological characteristics in the Ordos Plateau.

关 键 词：地下水埋深 植被盖度 气候梯度 干旱区 鄂尔多斯 

分 类 号：P641.2[天文地球—地质矿产勘探]