基于MIKE 11模型的引江济淮工程涡河段动态水环境容量研究

Environment Capacity of the Guohe River in the Water Transfer Project from Yangtze River to Huaihe River Based on a MIKE 11 Model

为探索分析水体环境容量的动态特性,论文以引江济淮工程涡河段为例,首次提出MIKE 11模型结合稀释流量比m值法计算河流水环境容量。计算结果表明:1)基于MIKE 11模型的m值法计算环境容量来分析河流水体环境容量的动态特性是可行的,它综合了环境管理中的总量控制和质量控制思想。2)通过对参数的合理取值,可建立客观反映模拟河段水动力、水质时空演变规律的模型;MIKE 11模型综合考虑河床糙度、纵向扩散系数、综合衰减系数、地表储水层最大含水量、土壤或根区储水层最大含水量等因素,水深的绝对误差(Re)、确定性系数(R2)和Nash-Suttcliffe系数Ens分别为3.30%、0.990和0.984;流量的Re、R2和Ens分别为9.8%、0.969和0.997;义门大桥断面COD模拟误差为13.7%,氨氮模拟误差为14.7%。3)基于MIKE 11模型的m值法计算谯城区COD的月均环境容量为-220.48 g/s、氨氮的月均环境容量为-10.97 g/s;涡阳县COD的月均环境容量为-17.05 g/s、氨氮的月均环境容量为2.56 g/s;蒙城县COD的月均环境容量为30.58 g/s、氨氮的月均环境容量为4.47 g/s;怀远县COD的月均环境容量为176.59 g/s、氨氮的月均环境容量为10.67 g/s;与传统的一维模型计算值相比,计算精度更高。结论认为,此方法可为MIKE 11模型的应用拓宽新思路,为引江济淮工程中河流水体的动态水环境容量计算提供依据,为污染物在横断面均匀混合的非感潮河流水体的环境容量计算和流域水污染治理提供一种新的技术方法。

In order to assess the dynamic characteristics of environment capacity, the m value of assimilative capacity method based on the MIKE 11 model was first proposed and applied in the Guohe River in the water transfer project from Yangtze River to Huaihe River. The result showed that： 1） It is feasible to analyze the dynamic characteristics of river water environment capacity through this method, as it integrates total maximum daily load with pollutant concentration control. 2） The model reflecting the space-time evolution of COD and ammonia nitrogen can be built with reasonable parameters. The MIKE 11 model takes into account of factors such as river bed roughness, longitudinal diffusion coefficient, integrated attenuation coefficient, maximum water content of surface water storage layer, maximum water content of soil or root zone water storage layer and other factors. The Re, R2 and Ens of simulated water depth are 3.30%, 0.990 and 0.984 respectively. The Re, R2 and Ens of flow rate are 9.8%, 0.969 and 0.997 respectively. The COD simulation error at the cross section of Yimen Bridge is13.7%, and the simulation error of ammonia nitrogen is 14.7%. 3） With the m value of assimilative capacity method based on the MIKE 11 model, the monthly average environmental capacity of COD is-220.48 g/s and the average monthly environmental capacity of ammonia nitrogen is-10.97 g/s in Qiaocheng area; the monthly average environmental capacity of COD is-17.05 g/s and the average monthly environmental capacity of ammonia nitrogen is 2.56 g/s in Guoyang County; the monthly average environmental capacity of COD is 30.58 g/s and the average monthly environmental capacity of ammonia nitrogen is 4.47 g/s in Mengcheng County; the monthly average environmental capacity of COD is 176.59 g/s and the average monthly environmental capacity of ammonia nitrogen is 10.67 g/s in Huaiyuan County.Compared with 1-D model, the m value in assimilative capacity method based on the MIKE 11 model is more accurate. This method can broaden the application of the MIKE 11 model. The result could provide technical support to calculate dynamic environmental capacity in the water transfer project from Yangtze River to Huaihe River and contribute to river training works.