College of Civil Engineering, Nanjing Forestry University, Nanjing 210037, China.
Ecological Complexity and Modeling Laboratory, Department of Botany and Plant Sciences, University of California, Riverside, CA 92521, USA.
Int J Environ Res Public Health. 2022 Sep 2;19(17):10976. doi: 10.3390/ijerph191710976.
Floodgate operation is one of the main forms of river regulation in the development and utilization of river basins. It changes the natural structure, flow process, and correlative environment of rivers. However, there is little analysis of the multiple impacts of small floodgate operation on the water environment in river networks and of the regulation patterns of urban floodgate infrastructure on pollution. In this paper, a one-dimensional hydrodynamic-water quality model, MIKE 11, was used, taking Wuxi's two main pollutant indicators-the permanganate index (COD) and ammonia nitrogen (NH-N)-to simulate the water quality response of Wuxi's river network based on different design solutions of urban floodgate infrastructure. The results show that among the three design scenarios, the order of the decreasing amplitude of the COD and NH-N concentrations was as follows: 1.4 m design solution scenario > 2.1 m design solution scenario > 0.7 m design solution scenario. Meanwhile, under the 1.4 m scenario, the maximum decrease in the COD concentration reached 37.57%, and the maximum decrease in the NH-N concentration reached 206%. In the entire river network system, the improvement in the water quality in the downstream area was significantly better than that in the upstream area. In addition, under the three scenarios of floodgate operation, the changes in pollutant concentrations during the flood season (June-September) were significantly lower than those during the dry season (October-February) and the flat water season (March-May). The research results can provide theoretical support and new ideas for future research on the ecological operation of small floodgates and related research on the water environment effect.
水闸调度是流域开发利用中河流治理的主要形式之一，它改变了河流的自然结构、水流过程和相关环境。然而，对于小水闸调度对河网水环境保护的多方面影响，以及城市水闸基础设施的调度模式对污染的调控作用，分析较少。本文采用一维水动力水质模型 MIKE 11，以无锡的两个主要污染物指标高锰酸盐指数（COD）和氨氮（NH-N）为模拟对象，基于城市水闸基础设施不同设计方案，模拟了无锡河网的水质响应。结果表明，在三种设计方案中，COD 和 NH-N 浓度降幅的顺序为：1.4 m 设计方案>2.1 m 设计方案>0.7 m 设计方案。同时，在 1.4 m 方案下，COD 浓度的最大降幅达到 37.57%，NH-N 浓度的最大降幅达到 206%。在整个河网系统中，下游地区的水质改善明显优于上游地区。此外，在三种水闸调度方案下，雨季（6-9 月）污染物浓度的变化明显低于旱季（10-2 月）和平水期（3-5 月）。研究结果可为今后小水闸生态调度及相关水环境效应研究提供理论支持和新的思路。
