1999-2015年北京市丰台区自备井水硝酸盐污染地区分布特征

目的分析北京市丰台区农村饮用自备井水中硝酸盐浓度水平及其分布特征,为农村改水及健康风险管理提供数据支撑。方法利用1999-2015年北京市丰台区各乡镇自备井水硝酸盐监测资料,分析自备井水硝酸盐浓度在各地区间分布特征。结果 1999-2015年丰台区农村自备井硝酸盐合格率为44.06%(267/606),其中花乡合格率最低(14.84%),长辛店镇合格率最高(100.00%)。河东地区自备井水硝酸盐浓度(29.85 mg/L)高于河西地区(2.38 mg/L),差异有统计学意义(P<0.001);各乡镇间自备井水硝酸盐浓度差异有统计学意义(P<0.001),从高到低浓度排序为花乡(34.50 mg/L)>卢沟桥乡(26.70 mg/L)>南苑乡(25.00 mg/L)>王佐镇(2.89 mg/L)>长辛店镇(1.82 mg/L)。1999-2015年各年份中自备井水硝酸盐浓度在各乡镇间差异均有统计学意义(P<0.05)。结论 1999-2015年丰台区自备井水硝酸盐污染河东地区高于河西地区,并且17年来各乡镇间均存在显著性差异。为保障居民饮水健康,建议政府重点加强河东地区自备井水硝酸盐污染治理,可按照花乡、卢沟桥乡、南苑乡的顺序逐步推进。

Regional distribution characteristics of nitrate pollution of self-sufficient-well water in Fengtai district of Beijing, 1999-2015

Objective To analyze the level of nitrate in drinking water of rural self-sufficient-wells and its distribution characteristics in Fengtai district of Beijing, and to provide data support for rural water safety improvement and health risk management. Methods The monitoring data of nitrate in water of self-sufficient-wells in each township in Fengtai district during 1999-2015 were used for analyzing the distribution characteristics of nitrate level in water of self-sufficient-wells in diffenent rural areas. Results The qualified rate of nitrate in water of rural self-sufficient-wells in Fengtai district during 1999-2015 was 44.06% (267/606). The lowest qualified rate was found in Huaxiang (14.84%), while the highest qualified rate in Changxindian (100.00%). The level of nitrate in water of rural self-sufficient-wells was higher in the Hedong area than in the Hexi area (29.85 mg/L vs. 2.38 mg/L), with a statistically significant difference (P<0.001). The level of nitrate in water of rural self-sufficient-wells in different townships showed statistically significant differences (P<0.001), and it was found to be the highest in Huaxiang (34.50 mg/L), followed by Lugouqiao (26.70 mg/L), Nanyuan (25.00 mg/L), Wangzuo (2.89 mg/L) and Changxindian (1.82 mg/L). There were statistically significant differences in the level of nitrate in water of self-sufficient-wells among the five townships in each year during 1999- 2015. Conclusions The level of nitrate in water of self-sufficient-wells in the Hedong area of Fengtai district in 1999-2015 was higher than that in the Hexi area, and there were statistically significant differences among the five townships within the seventeen years. To ensure the residents’ health related to drinking water, it is suggested that the government should strengthen the treatment of nitrate pollution in water of self-sufficient-wells in Hedong area, which can be gradually promoted in accordance with the order of Huaxiang, Lugouqiao and Nanyuan.