茂名市中小河流氮磷污染特征

Characteristics of Nitrogen and Phosphorus Pollution of Medium and Small Rivers in Maoming

茂名市中小河流水质监测结果表明:(1)中小河流有较高的氮磷和有机负荷,其中氨氮、总氮、总磷和CODCr的浓度均超出Ⅴ类地表水质标准的最大值,主要来源为农业面源污染;(2)CODCr空间污染分布特征呈现为近郊地区比中心城区污染更为严重,小型支流比中型河流污染严重,近郊地区应加强农业面源污染控制。

Water quality of medium and small rivers in Maoming city was monitored and the results showed that:(1)the rivers were under heavy eutropic condition,with high loadings of nitrogen,phosphorus and organic pollutants,and the concentrations of ammonia nitrogen,total nitrogen,total phosphorus and CODCr exceed the maximum value of the surface water standard of category V.The main source was agricultural non-point source pollution.(2)The distribution characteristics of CODCr space pollution mainly showed that the suburban area was more polluted than the central city,while the small tributary was more polluted than the medium-sized river.Therefore,the suburban area should strengthen agricultural non-point source pollution control.