寒区乡村河流生态修复工程环境效应分析

Analysis on environmental effect of ecological restoration project of rural river in cold region

人为干扰造成的乡村河道环境改变,如护岸缺失、水文阻隔、河岸带侵占等是导致乡村河流自净能力等生态功能降低的重要因素。针对这些问题,以吉林省东辽河支流公主岭市怀德镇乡村河段开展的生态修复工程为研究区,通过实地调查、资料分析,以及在不同季节对典型水质指标的监测,系统梳理了研究区已实施的生态修复工程措施,探究了修复工程的环境效应。结果表明:近自然的工程措施具有较好的运行效果,对NH_(4)^(+)-N、NO^_(3)^(-)-N、TN、TP、COD的最大去除率分别为96.49%、43.92%、49.69%、8.3%、25.95%,DO的最大增加率为77.96%。工程的环境效应有明显的季节性,典型污染物的最大去除率出现在春季和夏季。工程能够适应寒区低温环境,在冬季NH_(4)^(+)-N、NO^_(3)^(-)-N、TN、COD的去除率分别为2.49%、38.5%、21.21%、15.9%,DO的增加率为2%。该工程能够为我国寒区乡村河流治理提供方法和技术借鉴。

The changes of rural river environment caused by human disturbance,such as the lack of bank protection,hydrological barrier and riparian encroachment,are important factors that lead to the reduction of ecological functions such as self-purification capacity of rural rivers.In view of these problems,this study takes the ecological restoration project carried out in the rural reach of Huide Town,Gongzhuling City,Tributary of Dongliao River,Jilin Province as the study area.Through field investigation,data analysis,and monitoring of typical water quality indicators in different seasons,the ecological restoration measures implemented in the study area were systematically sorted out,and the environmental effects of the restoration projects were explored.The results show that the near-natural engineering measures have a good operation effect.The maximum removal rates of NH_(4)^(+)-N,NO^_(3)^(-)-N,TN,TP,COD are 96.49%,43.92%,49.69%,8.3%,25.95%,respectively,and the maximum increase rate of DO is 77.96%.The environmental effect of the project has obvious seasonality.The maximum removal rate of typical pollutants occurs in spring and summer.In winter,the removal rates of NH_(4)^(+)-N,NO^_(3)^(-)-N,TN and COD are 2.49%,38.5%,21.21%and 15.9%,respectively,and the increase rate of DO is 2%.This project can provide methods and technical reference for river governance in cold areas of China.