三峡库区巫山段三期蓄水前后水质状况及其变化趋势研究

Water Quality Change in Wushan Section of the Three Gorges Reservoir Area around the Third Stage Impoundment

根据长江巫山段六个断面2005年和2007年枯、平、丰的水质监测结果,通过对培石断面2005年和2007年的对比,可以看出三期蓄水前后长江水质比较稳定,仍为Ⅱ类水质。通过对2005年和2007年培石断面的各实测指标比较分析可以看出DO、CODMnBOD5、TP指标2007年均出现不同程度的下降,而NH3-N、TN则呈现升高的趋势。但各支流由于受干流回水顶托影响,水环境趋于复杂,部分河段出现水华现象,需引起高度重视。

In this paper, monitoring results of water quality in high, middle and low flow periods of 2005 and 2007 from 6 sections were analyzed in Wushan. Water quality in main stream of Yangtze River was the second class generally. Compared with 2005, some measured indexes as DO, CODMn, BOD5 and TP were lower in 2007. However, NH3 - N and TN possessed the opposite trend. As far as tributaries, water quality became more complex affected by Jacking of backwater from main stream and algae bloom appeared in some reaches, on which more attentions should be paid.