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塔里木盆地南缘第四系松散沉积物以第三系弱透水层为隔水底板构成良好的储水场所 ,含水层厚 2 0 0～90 0 m,主要由冲洪积卵砾石、砂砾石和细砂组成。地下水位埋深由山前倾斜平原的 5 0～ 10 0 m逐渐过渡为细土平原的 1～ 3m,矿化度相应地由 1～ 3g· L- 1 变化到 3～ 5 g· L- 1 。大部分地下水由地表径流和渠系、田间灌溉水入渗转化而成 ,约占地下水补给总量的 94%以上。人类历史时期 ,气候在地下水演变中依旧起着主导作用。随着人类社会文明的进步 ,人类活动对水资源系统的影响在环境变迁中表现出越来越显著的作用。 195 0— 1995年的 46 a中 ,塔里木盆地南缘地下水的开发利用比较有限 ,仅占 2 .3%左右 ,但地下水补给量减少了 2 6 .2 % ,与此同时 ,地下水位下降了 3～ 5 m,泉水递减了 2 8.7%。适于荒漠植物生长的地下水位埋深为 3～ 4m,高于此埋深将引起土壤盐渍化 ,低于此埋深植被会衰退进而导致土地沙漠化。因此 ,在开发利用水资源促进区域经济发展的同时 ,要重视地下水的保护和环境的改善。
Quaternary loose sediments in the southern margin of the Tarim Basin constitute a good water storage site with impervious bottom plates of the Tertiary Permeable Aquifer. The aquifer is 200 ~ 90 0 m thick. It is composed of alluvial sediment gravel, sand and gravel and fine Sand composition. The depth of groundwater table is gradually changed from 50 ~ 100 m to 1 ~ 3 m in fine plains, and the salinity changes from 1 ~ 3 g · L -1 to 3 ~ 5 g · L -1, respectively . Most of the groundwater from surface runoff and canal system, irrigation water infiltration into the field, accounting for more than 94% of the total groundwater recharge. In the historical period of mankind, the climate still plays a leading role in the evolution of groundwater. With the progress of civilization in human society, the impact of human activities on water resources system has played an increasingly significant role in environmental changes. During the 46 years from 1995 to 1995, the development and utilization of groundwater in the southern margin of the Tarim Basin was relatively limited, accounting for only about 2.3%, but the groundwater recharge decreased by 26.2% while the water table dropped by 3% ~ 5 m, spring decreased by 2 8.7%. The depth of groundwater table suitable for the growth of desert plants is 3 ~ 4m. Above this depth, soil salinization will occur. Below this depth, the vegetation will decline and the land desertification will result. Therefore, while developing and utilizing water resources and promoting regional economic development, we should pay more attention to the protection of groundwater and the improvement of the environment.