鲁西北平原区浅层孔隙水Mn超标特征分析

Analysis on the Characteristics of Mn Excess the Standard in Shallow Groundwater in the Plain Area of Northwestern Shandong Province

摘要:

鲁西北平原区位于山东西部，是重要的工业基地和粮食产区，面临着地下水资源缺乏和水质不佳的问题，浅层孔隙水中Mn含量超标严重。利用区内建立的国家地下水监测工程网络，测试浅层孔隙水中Mn的含量，分析地下水中Mn含量与水文地质条件和地下水化学特征的关系。结果表明：研究区内浅层孔隙水中Mn含量较高，平均值0.847mg/L，最大浓度为4.91mg/L，单指标评价结果超过Ⅲ类限值的监测点227个，超标率81.9%；在山前冲洪积平原区、黄泛平原区和滨海平原区，含水层岩性和地下水径流条件是影响Mn的迁移和富集的主要因素，受人类活动影响改变的地下水酸碱环境和海水入侵在局部地区形成了Mn高值区。从成因来看研究区锰超标属于背景值偏高。

Abstract:

The plain area in northwestern Shandong province is an important industrial base and grain producing center of China. But this area is lack of groundwater resources and water quality is poor. The content of manganese in local shallow groundwater exceeds the standard seriously. The content of manganese in groundwater is set up by using water samples obtained from the National Groundwater Monitoring Network established in the area. The relationship between manganese content in groundwater and hydrogeological conditions and groundwater environmental chemistry has been analyzed. It is showed that the content of manganese in the shallow groundwater in the study area is relatively high. The average value is 0.847mg/L and the maximum concentration is 4.91mg/L. There are 227 samples exceed Ⅲ grade of manganese content threshold, which covering 81.9%. The lithology of aquifer and groundwater runoff conditions are main factors affecting the migration and enrichment of manganese in shallow aquifer. Some areas with high value manganese are founded controlled by acid environmental condition and seawater intrusion according to human activities. In view of the formation, the excessive manganese in the study area is mainly controlled by high background value.