黄河流域地下水资源状况及其生态环境问题

Groundwater resource and eco-environmental problem of the Yellow River Basin

黄河流域是中国重要的生态屏障和经济地带,上中下游面临着不同生态环境问题,水在生态环境问题的形成演化过程中起着重要作用。本文从黄河流域地下水动态特征、地下水资源的数量、质量及开发利用等方面,分析了黄河流域地下水资源及饮水安全状况。黄河流域年度地下水资源量393.55亿m3,银川平原、河套平原等7处主要平原(盆地)地下水资源量为81.91亿m3,占比超过20%;黄河流域地下水质量以Ⅰ~Ⅳ类为主,劣质地下水主要受总硬度、硫酸盐、铁、溶解性总固体等天然原生组分影响,砷、氟、硒、碘等原生组分超标是流域部分地区地下水饮水安全的主要威胁;2020年与2019年同期相比,黄河流域地下水位呈上游稳定、中游局部上升、下游下降的态势,主要地下水降落漏斗形态基本稳定。针对黄河源区、宁蒙河套平原等重点区段,分析了存在的主要生态环境问题,提出了全面开展流域水文地质与水资源调查评价,深入开展黄河流域及重点地区水平衡分析等工作建议。

The Yellow River basin is an important ecological barrier and economic zone in China. The upper, middle and lower reaches of the Yellow River are faced with different ecological environmental problems. Water plays an important role in the formation and evolution of ecological environmental problems. Based on the quantities, qualities, settlements and dynamic characters of groundwater, the groundwater resources and the drinking water safety of the YRB were analyzed. The results show that total avenue groundwater resource of the YRB in 2019 is 3.93×1010 m3. Groundwater resources in seven key plain regions, such as Yinchuan plains and Hetao plains, is 8.19 × 109 m3, contributing more than 20% groundwater resources of the whole basin. The groundwater qualities in YRB dominated is mainly classified asⅠ-Ⅳ grade. The concentration of total hardness, sulfate, iron, TDS and Cl-exceed the groundwater standard at high rate. Excessive arsenic, fluoride, selenium, iodine and other primary components threaten the local drinking water safety. Compared with the same period in 2019, the groundwater table kept stable in the upper reach, local rising in the middle reach and decreasing in the lower reach in 2020. The morphological characters of main groundwater depression cone kept basically stable. Focusing on the key regions of the YRB, such as the sources area, Hetao Basin, etc., based on the analysis of the eco-environmental problems, it is proposed to carry out the whole basin resource survey and assessment, deeply develop water balance research in the whole basin and key regions.