渭河陕西段河水水质COD、NH3-N变化特征分析

渭河是黄河的一级支流,是重要的地表水体。随着近年来国民经济的飞速发展,工业农业用水量不断上升,排入渭河的污染物质逐年增加,致使渭河的水质污染不断加剧,已基本丧失了其原有功能。分析渭河水质变化特征对于防治渭河水污染具有重要的指导作用。通过对渭河干流的19个监测断面以及渭河(陕西段)断面的COD和NH3-N监测数据进行统计分析。结果表明:虽然渭河的水质总体恶化趋势得到有效的遏制,但渭河干流仍有1/2的监测断面没有达到水环境功能的要求,2007-2011年虽然渭河一些断面的水质仍为劣Ⅴ类,但COD和氨氮的浓度呈逐年降低的趋势。

Characteristic analysis of COD and NH3-N change of water quality in Shaanxi section of Weihe River

As the largest tributary of the Yellow River , the Weihe River is the important earth's surface water body in Guanzhong region of Shaanxi Province. With the rapid development of nation economy and the ascent of water consumption in recent years, the pollutant discharged into the Weihe River have increased year by year.The pollution of water quality in the Weihe River has been growing ,which makes the Weihe River lose its original function.The analysis of change characteristic of water quality has impoetant guide role for the pollution prevention of the Weihe River. On the basis of measured value from 19gauging station along the Weihe River in Shaanxi Province, the paper analyzed the variability of two main pollutants of COD and NH₃-N. The result indicated that the values of both COD and NH₃-N of 50% measured section are greater than the threshold values of surface water quality standard according to the water environmental functional district planning. Although the water quality of some section was still V grade, the concentration of COD and NH₃-N appeared decrement tendency from 2007to 2011.