基于BP神经网络和协调度的河流健康评价

为了对河流的健康状况进行评价,以解决河流健康评价中评价指标权重人为主观性太强的问题。采用BP神经网络对袁河的自然生态状况和社会服务功能分别进行模拟,并结合协调度来判断两者之间是否和谐发展。结果表明:(1)2016年度袁河宜春段和新余段河流健康综合评价指数T0.6,均达到健康等级;其中宜春段的协调度指数D=0.8,达到良好协调类别,新余段的协调度指数D=0.79,达到中度协调类别;(2)2006和2010年袁河宜春段和新余段的自然生态状况指数f(x)较前一年有所下降,经对比指标数据,主要因素是袁河2006和2010年水质由前一年Ⅲ类水质下降为Ⅳ类水质;(3)2016年袁河新余段的自然生态状况指数f(x)=0.59,要远小于社会服务功能指数g(y)=0.68,所以今后对于袁河新余段的河流政策应偏向于河流的自然生态修复。

River Health Assessment Based on BP Neural Network and Coordination Degree

Abstract：In order to evaluate the health conditions of rivers and solve the problem of the highly subjective weights of evaluation indicators in river health assessment, BP neural network is used to simulate respectively the ecological status and social service function of the Yuan River and to judge by coordination degree whether they are developing in a coordinative way. The results show that: (1) The comprehensive evaluation index of the river health within Yichun section and Xinyu section in 2016 is greater than 0.6, which indicates that the river is healthy. The coordination index of Yichun section is 0.8, which shows it is well coordinated. In comparison, the coordination index of Xinyu section is 0.79, which means it is moderately coordinated. (2) Compared with the previous year, the natural ecological status index fx of Yichun section and Xinyu section in 2006 and 2010 decreased, comparative indicator data ,which was mainly caused by the degraded water quality of the Yuan River that went down from the previous Grade III to the present Grade IV;(3) The natural ecological status index fx of Xinyu section in 2016 stands at 0.59, which is much smaller than the social service function index of 0.68. Therefore, it is suggested that the natural ecological restoration be privileged in the future river policy for Xinyu section of the Yuan River.