引水改善城市河网水质效果评估研究

Assessing the Efficacy of Water Diversion to Improve Water Quality in City River Network

引水仍是目前改善城市河网水质最常用的方法之一,但引水对河网水质改善的整体效果缺乏统一的评价标准和评估体系。以杭州市江干区为例,构建了一维河网水质模型,模拟了不同的引水水量和水源水质方案下河网水质改善情况;利用水质改善率、类别变化指数和浓度变化指数分析了引水对河网水质的改善效果。结果表明:引水水量对河网水质有一定的改善效果,但随着引水水量的增大,河网水质改善幅度逐渐变小;水源水质的提升对河网水质提高有明显效果,且改善幅度随水质的提升而提高,是影响引水效果的关键因素。

Water diversion is one of the most common methods to improve water quality in city river network.How-ever,there is no uniform standard or system to evaluate the diversion effect.With Jianggan District of Hangzhou City as a case study,we built a one-dimensional river network model to simulate the water quality in different diver-sion cases,and assessed the effect of water quality improvement through the rate of water quality improvement,the category change index and concentration change index.Results showed that increasing water quantity could improve the water quality of the city rivers,however,the efficiency decreased with the increase of water quantity.Moreo-ver,the improvement of source water quality is a crucial factor which affects the diversion effect as it could appar-ently improve the water quality of river network,and the rate of improvement also increased with the improvement of the source water quality.