城市湖泊生态修复的水质响应研究

Study on water quality response for urban lake ecological restoration

生态修复对遏制城市湖泊生态系统的退化意义重大,寻找一种有效且简单的生态修复效果预测方法有利于进一步推动湖泊修复研究的发展。利用综合污染指数法、基于专家调查法的湖泊污染物浓度确定方法及水质提升贡献度分析了生态修复的水质响应,并采用基于污染负荷平衡的水质模型预测了生态修复措施作用下的潜龙渠水质。结果表明:4种污染物浓度均有下降,潜龙渠水质提升显著,但各污染物对不同修复措施的响应程度不同,COD的浓度控制需要污染源控制与修复净化的共同支撑,TN对各项措施的敏感性接近,TP、NH_3—N分别对污染源控制、生态补水敏感性最高。情景预测表明,依据水质响应关系制定的生态修复方案,能够稳定保持潜龙渠的生态修复效果。

Ecological restoration is of great significance in curbing the degradation of urban lake ecosystems. Finding an effective and simple prediction method for ecological restoration effects is conducive to further promote lake restoration research. In this paper,water quality response to ecological restoration is analyzed using comprehensive pollution index method,lake pollutant concentration determination method based on Delphi method and contribution to water quality improvement,and the water quality model based on pollution load balance is used to predict Qianlong lake’s water quality under the ecological restoration measures. Results of calculation and evaluation illustrated that all of the concentrations of four pollutants declined and the water quality of Qianlong Lake significantly improved,while the response degree of different pollutants to ecological restoration measures was different. The control of COD concentration requires supports of pollution source control and repair purification. The sensitivity of TN to different measures are close. TP and NH3—N showed highest sensitivity to pollution control and ecological hydrating,respectively. Scenario prediction showed that the ecological restoration scheme based on water quality response relationship enables Qianlong lake to maintain the ecological restoration effect stably.