水生态学杂志2025，Vol.46Issue(5)：63-77,15.DOI:10.15928/j.1674-3075.202502270001
水文连通性视角下面向水质改善的感潮河网生态流量研究
Assessing Environmental Flow Thresholds for Water Quality Improvement in a Tidal River Network from a Hydrological Connectivity Perspective
摘要
Abstract
Freshwater scarcity and water quality degradation caused by urbanization are major challeng-es in deltaic tidal river networks.Effective assessment of environmental flow(EF)is essential for mitigat-ing pollution-induced water shortages and ensuring sustainable regional development.However,complex interactions between runoff and tidal dynamics,coupled with limited spatiotemporal coverage of runoff monitoring,complicates precise determination of EF.In this study,we selected the Dongjiang Delta tidal river network for a case study.Ecological flow thresholds for water quality improvement in the tidal river network were explored and the hydrological connectivity and water quality response mechanisms under the influence of coupled runoff and tides were investigated.We aimed to provide a scientific basis for im-proving water quality and managing ecological flows in tidal river networks.First,key water quality indi-cators were identified using principal component analysis based on water quality data from 2018.Then dy-namic hydrological connectivity metrics were constructed and a one-dimensional hydrodynamic-water quality coupled model was developed to simulate hydrological connectivity and water quality responses under varying runoff-tide scenarios.Finally,the Tennant method was applied to establish an ecological flow management scheme.Results show:(1)Hydrological connectivity was more sensitive to variations in runoff than tidal fluctuations.The response to changes in runoff(average increase of 27.7％across sub-networks)was significantly higher than the response to tidal fluctuations(average increase of 7.3％).The variation in hydrological connectivity during flood season was greater than that during non-flood season,and different sub-river networks exhibited regional differences in response to fluctuations in runoff and tides.(2)Runoff exerted a stronger pollutant removal effect,while tides tended to induce oscillation and retention of pollutants during low-flow periods.(3)Maintaining an ecological flow of ≥451.47 m3/s(ap-proximately 60％of the multi-year average runoff)would effectively enhance hydrological connectivity and improve water quality,with optimal improvement rates of 8％for TN and 20％for TP.Nevertheless,the improvement of water quality through flow regulation alone is limited.In the future,strategies should integrate pollutant source reduction and other comprehensive measures to achieve substantial and sustain-able enhancements in aquatic environmental quality.关键词
感潮河网/水文连通性/水质改善/生态流量/东江三角洲Key words
tidal river network/hydrological connectivity/water quality improvement/environmental flow/Dongjiang Delta分类
资源环境引用本文复制引用
张济显,艾丽莎,杨盈,张宇健,徐志豪..水文连通性视角下面向水质改善的感潮河网生态流量研究[J].水生态学杂志,2025,46(5):63-77,15.基金项目
国家自然科学基金项目(52239005,51979042) （52239005,51979042）
松山湖科技特派员项目(20234424-01KCJ-G). （20234424-01KCJ-G）
