Kunming Institute of Eco-Environmental Sciences, Yunnan, Kunming, China; Beijing Normal University, Beijing, China.
Kunming Institute of Eco-Environmental Sciences, Yunnan, Kunming, China.
Environ Res. 2020 Jul;186:109479. doi: 10.1016/j.envres.2020.109479. Epub 2020 Apr 11.
In a lake basin, there is a mismatch between river and lake water quality targets and a method for setting specific water quality targets for these rivers is urgently needed. Using Dianchi Lake as an example, we proposed a lake basin water quality management system based on the river-lake water quality response relationship, coupled with a Soil and Water Assessment Tool (SWAT) basin hydrological model and Environmental Fluid Dynamics Code (EFDC) lake water quality hydrodynamic model. River water quality control requirements based on the river-lake water quality response were proposed, under the premise that the Dianchi Lake water quality reaches the required standard. Then, water quality control targets for rivers were determined, and corrected for influencing factors, such as current river water quality and composition of flow. Our systematic approach efficiently identified key lake basin pollution sources, and accurately located key points for water quality improvement and pollution control. Combined with a correction for clean water source and current water quality of each river, the proposed water quality targets were practical and operable. Meanwhile, the EFDC model was used to verify the entire process to ensure that river water quality targets could be set to achieve lake water quality targets. To ensure that Dianchi Lake water quality can reach Class IV standard, the Chemical oxygen demand (COD) concentration would need to be maintained under 30 mg/L,Waihai total nitrogen (TN) below 7 mg/L, total phosphorus (TP) below 0.2 mg/L, and ammonia nitrogen (NH-N) below 2 mg/L.
在湖泊流域中，河流水质目标与湖泊水质目标之间存在不匹配的情况，因此迫切需要一种为这些河流设定具体水质目标的方法。以滇池为例，我们提出了一种基于河湖水质响应关系的湖泊流域水质管理系统，结合流域水文模型 Soil and Water Assessment Tool (SWAT) 和湖泊水动力模型 Environmental Fluid Dynamics Code (EFDC)。在滇池水质达到要求标准的前提下，根据河湖水质响应提出了基于河流水质控制要求的河流水质控制目标，并对当前河流水质和流量组成等影响因素进行了修正。我们的系统方法有效地识别了关键的湖泊流域污染源，并准确地找到了水质改善和污染控制的关键点。结合每条河流的清洁水源和当前水质的修正，所提出的水质目标具有实际可操作性。同时，使用 EFDC 模型对整个过程进行了验证，以确保可以设定河流水质目标来实现湖泊水质目标。为了确保滇池水质达到 IV 类标准，需要将外海 COD 浓度控制在 30mg/L 以下，总氮（TN）低于 7mg/L，总磷（TP）低于 0.2mg/L，氨氮（NH-N）低于 2mg/L。
