渭河干流关中段水污染时空变化及其与径流量的关系

Relationship between Spatiotemporal Variation of Water Pollution and Runoff Volume of Mainstream Section of the Weihe River in Shaanxi Province

立足于环境容量的分区分时控制,依据2000-2004年水质监测资料,对渭河关中段4种主要污染因子的时空变化及其与河川径流量的关系进行了分析。结果发现:①高锰酸盐指数、氨氮离子、BOD浓度沿河流断面呈上升趋势,而DO呈下降趋势,其中,天江人渡、沙王渡和树园3个断面高锰酸盐指数、氨氮离子、BOD浓度最高,属于严重污染断面;②高锰酸盐指数在各个断面上年际变化相对较小,而BOD在临近市区河段变化较为剧烈,呈逐年上升趋势;③高锰酸盐指数、氨氮离子分别与河流径流量呈负指数相关,且相关性显著;④径流量相对于高锰酸盐指数和氨氮离子浓度变化存在一个极值,当径流量大于这个极值时,河流能够保持足够的自洁能力;反之,河流会进一步污染。该研究成果可为实现渭河流域内环境经济协调发展提供参考依据。

In order to control environmental capacity divisionally in time-sharing way,in this paper the water quality monitoring data measured during the period from 2000 to 2004 were used to analyze the spatiotemporal variation of the 4 main pollution factors and their relationships with runoff volume of mainstream section of the Weihe River in Shaanxi Province.The result are as follows：（1） Permanganate index,ammonium ion and the BOD concentration were in an increase trend at all the cross sections,but the DO was in a decrease trend;（2） The annual variation of permanganate index at all the cross sections was relatively low,but the variation of BOD along the river section close to the urban area was intensive and in an increase trend year by year;（3） There was a significant negative exponent correlation between the permanganate index and ammonium;（4） There was an extreme value of runoff volume for the variation of permanganate index and ammonium ion concentration,when the runoff volume of the river was higher than the extreme value,an enough self-cleaning capability of the river could be maintained;on the contrary,stream water would be further polluted.The study results can be referred for achieving the goal of the coordinated development of economy and environment in the Weihe River Basin.