摘要
针对城市河道治理后反复出现水华现象的问题,以上海市青浦区小涞港河段为研究区域,基于层次分析法和熵权法的组合赋权法,参考相关研究并结合实地调查,优化选取水质、底泥、护岸等相关指标建立评价指标体系,进行河道生态修复效果评价。结果表明:较高的硝酸盐浓度[NO3--N浓度为(3.055±2.863)mg/L,其与叶绿素a浓度显著相关,r=0.36,P<0.05]是闸控型平原河网水系河流重要的水华潜在风险因素,建议结合现有闸泵工程活水畅流技术,进一步优化曝气方式,创造合适的缺氧微环境以及通过硫、铁元素耦合强化总氮去除;河道底泥以营养盐污染[内源氮浓度为(2171.99±1664.40)mg/kg]为主,现有沉水植物种类较为单一,易产生丝状藻华孳生现象,建议增加沉水植物的种类并进行合理配置,降低底泥营养盐污染,增强以沉水植物为核心的水生生态系统稳定性;采用的浆砌混凝土硬质护岸对雨水径流污染的净化拦截能力严重不足,建议适当拓宽河道,对护岸进行生态化改造,选择合理的填料基质和植被配置,以强化护岸对面源污染的截留功能。
To confront the problem of repeated bloom after urban river control,the Xiaolaigang reach in Qingpu District of Shanghai was taken as the research area and the river ecological restoration effect was evaluated.Based on the combination of analytic hierarchy process and entropy weight methods,referring to relevant studies and field investigations,the evaluation index system was established by optimizing and selecting relevant indicators such as water quality,sediment,and bank protection.The results showed high nitrate content of(3.055±2.863)mg/L,which was significantly correlated with chlorophyll a(r=0.36,P<0.05),was an important potential risk factor for blooms in the gate-controlled plain river network.The aeration mode could be further optimized to create a suitable anoxic microenvironment and enhance total nitrogen removal by coupling sulfur and iron elements,in combination with the existing sluice pump engineering live water smooth flow technology.The sediment of river channel was mainly polluted by nutrient salt with the endogenous nitrogen content of(2171.99±1664.40)mg/kg.The existing submerged plant species were relatively simple,which was easy to produce filamentous algal blooms.The species of submerged plants could be increased,and the rational allocation could reduce the nutrient salt pollution of the sediment and enhance the stability of the aquatic ecosystem with submerged plants as the core.The purification and interception ability of rainwater runoff pollution by the slurry concrete rigid bank revetment was seriously insufficient.Therefore,the river channel could be properly widened,the ecological transformation of the bank revetment could be carried out,and reasonable filler matrix and vegetation allocation could be selected to strengthen the interception function of the bank revetment on non-point source pollution.
作者
范业弘
何岩
朱晗彬
赵凯豪
顾敦罡
黄民生
何培民
徐兵兵
何文辉
FAN Yehong;HE Yan;ZHU Hanbin;ZHAO Kaihao;GU Dungang;HUANG Minsheng;HE Peimin;XU Bingbing;HE WenHui(Shanghai Key Laboratory for Urban Ecological Processes and Eco-Restoration,School of Ecological and Environmental Sciences,East China Normal University;Institute of Eco-Chongming;Technology Innovation Center for Land Spatial Eco-Restoration in Metropolitan Area,Ministry of Natural Resources;Shanghai River and Lake Biological Chain Construction and Resource Utilization Engineering Technology Research Center;College of Chemistry and Chemical Engineering,Shanghai University of Engineering Science)
出处
《环境工程技术学报》
CAS
CSCD
北大核心
2023年第5期1849-1856,共8页
Journal of Environmental Engineering Technology
基金
上海市科技计划项目(20DZ2250700)
国家自然科学基金项目(41877477)
自然资源部大都市区国土空间生态修复工程技术创新项目(CXZX2021B02)
上海市城市化生态过程与生态恢复重点实验室主任基金项目(SHUES2022C01)。
关键词
闸控型河道
组合赋权法
河流健康评定
生态修复
生态系统重构
gate-controlled river
combination weighting method
river health assessment
ecological restoration
ecosystem reconstruction.
