近年来淮河干流氮污染状况与变化趋势

The relationship bettveen nitrogen contamination and dissolved oxygen in mainstream of the Huaihe River

对淮河干流1990年至2002年氮污染和溶解氧监测数据的分析表明,沿淮河干流上游至下游氮污染加重,溶解氧含量降低。在一年中的6～9月,淮河干流无机氮和溶解氧浓度为最低。溶解氧的浓度直接影响到氨氮向亚硝酸盐氮和硝酸盐氮转化这一氧化自净过程。

The relationship between nitrogen contamination and dissolved oxygen in mainstream of the Huaihe River has been studied. The results shows: form upper reaches to the lower reaches of the Huaihe Rive, the contents of nitrogen has a raising trend, but the concentration of dissolved oxygen is opposite ; from Jun to Sep of a year, the concentration of nitrogen contamination and dissolved oxygen is the lowest- The concentration of dissolved oxygen directly affects the self-purification that ammonia nitrogen transforms to nitrite nitrogen and nitrate nitrogen.