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在综合分析大量实测资料和参考资料的基础上,阐明了渭干河―库车河三角洲绿洲地下水不同埋深的分布面积、盐化特征、化学类型、补排量、含盐量的时空变化及成因。结果显示:(1)在绿洲平原区,地下水埋深3~6m范围最大,占总面积的39.68%;在灌区地下水埋深1~3m范围最大,占53.03%。在绿洲平原区,地下水矿化度小于1g/L范围最大,占总面积的91.98%;在灌区地下水矿化度小于1g/L的范围最大,占94.81%。从pH值来看,pH值7.5~8.0范围之间的面积最大,占总面积的90.25%。(2)冲积洪积扇北部属于淡水带,水化学类型为HCO3—Cl—SO4—Ca—Na;冲积洪积扇中部属于上咸下淡水带,水化学类型为SO4—Cl—Na—Mg;冲积洪积扇南部属于上咸下淡水带,水化学类型为Cl—SO4—Na—Mg。从水质上看,Ⅲ级地下水分布面积最大,占总面积的84.77%,其地下水资源量占61.89%。(3)地下水含盐量在时间尺度上,波动较大,1997、2000、2001年含盐量较高,均为3.7g/L以上,而1998、1999、2006年较低,为3.4g/L左右;在空间尺度上,研究区东部的地下水含盐量高于西部,南部高于北部,东南部高于西北部。(4)可溶性矿物的溶解、地下水水位抬升、强烈的蒸发、降水量的稀少、农业灌溉、化肥的使用是渭干河―库车河三角洲绿洲地下水含盐的主要原因。
Based on the comprehensive analysis of a large number of measured data and reference materials, the spatial and temporal variations of the distribution area, salinization characteristics, chemical types, uptake and discharge, and salinity of groundwater in the Weigan-Kuqa River delta oasis were described. Cause. The results show that: (1) In the oasis plain area, the depth of groundwater is 3 ~ 6m, accounting for 39.68% of the total area; the groundwater depth is 1 ~ 3m, accounting for 53.03% of the total. In the oasis plain area, the salinity of groundwater is less than 1g / L, accounting for 91.98% of the total area. In the irrigation area, the salinity of groundwater is less than 1g / L, accounting for 94.81% of the total. From the pH point of view, the pH range of 7.5 to 8.0 the largest area, accounting for 90.25% of the total area. (2) The northern part of the alluvial-alluvial fan belongs to the freshwater zone, and the hydrochemical type is HCO3-Cl-SO4-Ca-Na. The middle part of the alluvial-alluvial fan belongs to the upper salty freshwater zone, The alluvial-alluvial fan belongs to the upper salty freshwater zone, and the water chemistry type is Cl-SO4-Na-Mg. From the water quality point of view, Ⅲ grade groundwater distribution area is the largest, accounting for 84.77% of the total area, its groundwater resources accounted for 61.89%. (3) The salinity of groundwater fluctuated greatly on the time scale. The salt content of groundwater was higher than 3.7g / L in 1997, 2000 and 2001, but lower than that in 1998, 1999 and 2006, which was 3.4g / L; on the spatial scale, the salinity of groundwater in the eastern part of the study area is higher than that in the west, higher in the south than in the north and higher in the southeast than in the northwest. (4) Dissolution of soluble minerals, uplift of groundwater level, strong evaporation, sparse precipitation, agricultural irrigation and the use of chemical fertilizers are the main reasons for groundwater salinization in the Weigan-Kuqa River Delta oasis.