基于对应分析法的鄂尔多斯盆地东北部地下水污染分析

摘要

运用对应分析法,根据2014年野外调查资料,对鄂尔多斯盆地东北部不同含水层系统地下水污染现状进行分析,确定各子区主要污染物质,并探究其污染源与污染途径。结果显示：研究区西部内流区、无定河下游等地区,由于集中的农业生产,农药、化肥大量施用,导致污染物进入含水层,并随地下水流动,出现较严重的 NO3-污染；西北部平原区及大理河、窟野河等河流中下游,Cl-、Na+、TDS、SO42-含量较高,除潜水蒸发浓缩作用外,上游含较多Cl-的工业废水、生活污水及垃圾渗滤液入渗,随水流流动,造成Cl-、TDS升高。高硬度水在区内广泛分布,生活污水、固体垃圾渗滤液中可降解的有机物入渗后使得地下水中的CO2平衡压力升高,或工业酸性废水的酸性溶滤作用促进含Ca2+、Mg2+矿物的溶解,使地下水总硬度增大。%The current groundwater pollution conditions of different aquifersystems of Northeastern Ordos Basin were analyzed using correspondence analysis method using the monitored data in 2014. And the major pollutants, its pollution sources and pollution pathways were explored. The results indicate that pollution of NO3-was serious due to agricultural production, pesticides and fertilizers casting in the inner flow area of western study area and Wuding river downstream areas. In the inner flow area of western to the diving evaporation concentration effect, industrial wastewater, domestic sewage and garbage leachate with high Cl-content from the upstream infiltrates into the groundwater, leading to an increase of Cl- and TDS. High hardness water is widely distributed in study area, the leachate of biodegradable organic matter contained in domestic sewage and solid waste raises CO2 equilibrium pressure, or acidic leaching of industrial acidic waste water promote the dissolution of mineral containing Ca2+, Mg2+, leading to an increase of hardness.