牛世伟 安景文 宫亮 蔡广兴 何志刚 陈玥 刘子琪 隋世江

摘要：为了解和评价农业种植区域地下水硝酸盐含量状况，2005～2012年采集辽河流域典型农区2 839个井次的地下水样品，分析硝酸盐含量。结果表明，辽河流域典型农区地下水硝态氮平均为22.75 mg/L，井深小于或等于30 m地下水硝酸盐含量达到国家地下水质量标准的年份较少，井深30～100 m的除2011年外均达到标准，井深大于100 m的均能達到Ⅱ类水标准，各监测时期的硝酸盐含量和超标率有较大相关性；不同井深地下水硝酸盐含量差异明显，井深小于或等于30 m硝酸盐含量大于井深30～100 m的大于井深大于100 m的，随着井深深度的增加，地下水硝酸盐含量逐渐降低；以时间动态来看，硝酸盐含量总体呈逐年升高的趋势，超标可能性会进一步加大。

关键词：农业种植区域；地下水；硝酸盐；时空变化；井深；辽河流域

中图分类号：X523 文献标识码：A 文章编号：0439-8114（2016）05-1147-04

DOI：10.14088/j.cnki.issn0439-8114.2016.05.015

Spatial-temporal Change Characteristics of Nitrate in Groundwater in Typical Agricultural Areas of Liao River Basin

NIU Shi-wei，AN Jing-wen，GONG Liang，CAI Guang-xing，HE Zhi-gang，CHEN Yue，LIU Zi-qi，SUI Shi-jiang

（Institute of Plant Nutrition and Environmental Resources，Liaoning Academy of Agricultural Sciences， Shenyang 110161，China）

Abstract： By sampling groundwater samples from 2 839 wells in typical agricultural areas of Liao river basin from 2005 to 2012， the nitrate concentration was analyzed to understand and evaluate nitrate status in groundwater of agricultural cultivation areas. The results showed that the average nitric nitrogen concentration of groundwater in typical agricultural areas of Liao river basin was 22.75 mg/L. The groundwater nitrate concentration from wells less than 30 meters depth reached the quality criterion of national groundwater in few years， from the wells in 30～100 meters depth， which met the quality criterion except for 2011， and from wells more than 100 meters depth， all attained Class II water standard， there was a significant correlation between nitrate concentration and over standard rate in different monitoring periods. Nitrate concentration of groundwater was significantly affected by different well depth， in the order of less than 30 m>30～100 m> more than 100 m. With the increase of well depth， nitrate concentration of groundwater decreased gradually. From temporal dynamics， nitrate concentration increased year by year， resulting in the further increase of over standard possibility.

Key words：agricultural cultivation areas； groundwater；nitrate；well depth

随着集约化农业的发展，由于过于追求经济效益和农产品产量，在农田中过量施用化肥和农家肥，含氮物通过地表径流及淋溶进入水体，导致江河、湖泊、溪流及地下水等水源硝酸盐含量过高[1-4]。研究表明，水体中的硝酸盐进入人体能被还原成亚硝酸盐，能够形成致突变和致癌的亚硝基化合物[5]。水体硝酸盐含量超标问题得到人们的关注，上世纪80年代开展了地下水硝酸盐含量超标和控制措施等方面的研究[6]，为防控地下水硝酸盐超标开辟了途径。国内外地下水硝酸盐含量超标问题日益严峻，国外报道加拿大的安大略湖南部1 292口监测井有14%地下水硝酸盐含量超标[7]；澳大……