干旱区生态环境知识资源中心(Arid): 鄂尔多斯高原地下水与植被盖度的相互影响

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	鄂尔多斯高原地下水与植被盖度的相互影响
其他题名	INTERACTIONS BETWEEN GROUNDWATER AND VEGETATION COVERAGE IN ERDOS PLATEAU
	王旭升 1; 万力 1; 齐蕊 2; 蒋小伟 1; 黄金廷 3; 金晓媚 2; 梁四海 2
来源期刊	第四纪研究
ISSN	1001-7410
出版年	2014
卷号	34 期号:5 页码:1013-1022
中文摘要	鄂尔多斯高原位于我国干旱-半干旱过渡带,发育毛乌素沙地和库布其沙漠,其生态环境对地下水有较强的依赖性。利用2005~2012年地下水观测数据、2008年8月中下旬MODIS NDVI数据和同期陆面蒸散量评估数据,以NDVI为基础定义植被相对盖度,本文研究了鄂尔多斯高原植被盖度与浅层地下水的依赖关系,以及植被盖度对地下水补给的影响。研究区植被盖度的统计特征近似符合Gamma随机分布函数,当地下水埋深小于10m时,其均值和峰值明显随地下水埋深增大而减小,且峰值对地下水更敏感。植被盖度同时受到气候条件和地下水的影响,呈斑块状分布。蒸散系数(实际蒸散强度与蒸发潜力的比值)随植被相对盖度的增大而升高,两者的依赖关系可以近似表示为分段线性函数。基于此近似关系,本文估算了鄂尔多斯高原地下水净补给强度的多年平均值。结果显示植被稀疏的沙地有利于地下水补给,而植被生长较为旺盛的低洼地带因蒸发强烈形成地下水的排泄区。地下水、植被和陆面蒸散之间存在耦合关系。
英文摘要	Erdos Plateau (37°31’~40°45’N, 106°24’~111°07’N) is an area (ca.13*10~4km~2) in the arid and semiarid region in China, including Mu Us and Kubuqi deserts, where the ecological environment is strongly dependent on groundwater. The landscape in Erdos Plateau is mainly characterized by sand dunes and shurblands. Shallow groundwater in the sandy sediments is an essential source of water for plants. In this study, the interactions between vegetation coverage and groundwater are investigated. 987 observation wells with shallow groundwater data between 2005 and 2012 were collected from more than 1200 wells and boreholes in the whole Erdos Plateau. Most of the wells were located in the middle (Otoqo Qi and Uxin Qi) and south (Yanchi city) areas of the plateau, representing the groundwater conditions in the Mu Us Desert. Groundwater depth in wells was generally measured in the summer (from June to September). The contours of groundwater level in Hailiutu River catchment (a catchment in Erdos Plateau, ca.2600km~2) was built based on these observation data and applied to construct 500-m resolution raster data of groundwater depth. MODIS NDVI data in the late of August in 2008 were collected to estimate the relative vegetation coverage (C_(NDVI)) with 500-m resolution. The evapotranspiration coefficient, defined as the ratio of the actual evapotranspiration rate to the potential evaporation rate,was estimated for the same period and resolution using the evapotranspiration data assessed with remote sending method. The C_(NDVI) value shows an inhomogeneous distribution in the study area that affected by both climate and groundwater. It was found that the statistic property of C_(NDVI) can be approximated by the Gamma distribution and the key parameters are dependent on groundwater depth. When depth to water table is less than 10m, the average and maximum C_(NDVI) values significantly decrease with increase of groundwater depth, especially for the maximum value. The average C_(NDVI) value approximates to 20% and shows little response to groundwater when depth to water table is greater than 10m. This critical value of groundwater depth seems does not represent the maximum length of plant roots but imply the integrated impact of local topography, groundwater depth and utilization of groundwater in the 500-m scale elements. The evapotranspiration coefficient for mean annual water balance ranges between 0.15 and 0.50. It increases with increase of C_(NDVI) and this relationship can be approximated by segmental linear functions. Based on the approximated relationship, the mean net annual groundwater recharge in the Erdos plateau is estimated. In general, groundwater recharge increases from west to east, following the increase of mean annual precipitation. However, this distribution is disturbed by the inhomogeneous distribution of C_(NDVI). It is indicated that the sandy lands with low vegetation density (C_(NDVI) is generally less than 0. 2) is favorable for groundwater recharge, whereas the low lands with high vegetation density generally form local groundwater discharge area due to strong evapotranspiration. The groundwater is coupled with vegetation and evapotranspiration process.
中文关键词	地下水 ; 植被指数 ; 补给 ; 蒸散 ; 相互作用 ; 鄂尔多斯高原
英文关键词	groundwater vegetation index recharge evapotranspiration interactions Erdos Plateau
语种	中文
国家	中国
收录类别	CSCD
WOS类目	MINERALOGY ; PLANT SCIENCES ; REMOTE SENSING ; GEOSCIENCES MULTIDISCIPLINARY
WOS研究方向	Mineralogy ; Plant Sciences ; Remote Sensing ; Geology
CSCD记录号	CSCD:5235975
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/231011
作者单位	1.中国地质大学(北京), 教育部地下水循环与演化重点实验室, 北京 100083, 中国; 2.中国地质大学(北京)水资源与环境学院, 北京 100083, 中国; 3.中国地质调查局西安地质调查中心, 西安, 陕西 710054, 中国
推荐引用方式 GB/T 7714	王旭升,万力,齐蕊,等. 鄂尔多斯高原地下水与植被盖度的相互影响[J],2014,34(5):1013-1022.
APA	王旭升.,万力.,齐蕊.,蒋小伟.,黄金廷.,...&梁四海.(2014).鄂尔多斯高原地下水与植被盖度的相互影响.第四纪研究,34(5),1013-1022.
MLA	王旭升,et al."鄂尔多斯高原地下水与植被盖度的相互影响".第四纪研究 34.5(2014):1013-1022.