扩大入江、入海泄量对洪泽湖及其上游淮干水位影响分析

为探究洪泽湖的出湖流量变化对洪泽湖的泄流能力以及淮河中下游水位的影响，建立淮河中下游一维、洪泽湖二维水动力数学模型，通过实测水文资料对模型进行率定及验证。基于数学模型，分析了扩大入江水道以及入海水道泄量对洪泽湖及淮河干流水位的影响。结果表明: 提高淮河入江水道泄流能力使其达到设计泄量，能使洪泽湖湖区内各个位置水位有所降低，其中蒋坝水位降幅最大，1991 年洪水时下降 0. 7 m，2003 年洪水时下降 0. 62 m，同时使淮河干流沿程水位均有不同程度的降低，从上游至下游沿程水位降幅呈逐渐增加的趋势。实施淮河入海水道工程对 1991 年型洪水洪泽湖湖区水位降低效果明显，其中蒋坝水位降幅最大，为 0. 06 m。淮河入海水道二期工程的启用能够使洪泽湖内水位有明显的降低，其中蒋坝水位降低幅度最大，1991 年洪水蒋坝水位降低 0. 3 m，溧河洼地区以及淮北淮南处降幅比蒋坝小，对淮干入湖河段水位的降幅相对比较小，到吴家渡水位降幅不明显。

Analysis on impacts from increasing discharges into Changjiang River and sea on water levels of Hongze Lake and main stream of Huaihe River

In order to explore the impact from the change of the outflow of Hongze Lake on the discharge capacity of the lake as well as the water level of the mid-lower reach of Huaihe River，an one-dimensional hydrodynamic mathematical model for the midlower reach of Huaihe River and a two-dimensional hydrodynamic mathematical model for Hongze Lake are established，and then both the models are calibrated and verified through the relevant measured hydrological data． Based on the mathematical models， the impacts from increasing both the discharge from Huaihe-Changjiang Water-way and the discharge from Huaihe River Watercourse to the Sea on the water levels of Hongze Lake and the mid-lower reach of Huaihe River are analyzed herein． The analysis result shows that making the discharge capacity of Huaihe-Changjiang Water-way reach its design discharge can make the water levels at all the locations within the area of Hongze Lake be decreased to some extent，in which the decreasing amplitude of the water level at Jiangba is the largest with the decreases of 0. 7 m during 1991 Flood and 0. 62 m during 2003 Flood，while it can also make all the water levels along the main stream of Huaihe River be decreased to different extents，thus the decreasing amplitudes of the upstream to downstream water levels along the river exhibit the trends of gradual increase． The effect from the implementation of the Project of Huaihe River Watercourse to the Sea on decreasing the water level that is similar to that occurred during 1991 Flood within the area of Hongze Lake is significant with the largest decreasing amplitude of the water level at Jiangba，i． e． 0. 06 m． The starting of the phase II of the Project of Huaihe River Watercourse to the Sea can make more obvious decrease of the water level in Hongze Lake，the water level of Jiangba Dam decreased by 0. 3 m in 1991 flood，in which the decreasing amplitude of the water level at Jiangba is to be the largest and the decreasing amplitudes in Lihewa Area as well as the areas of Huaibei and Huainan are less than that at Jiangba，while the decreasing amplitude of the water level at the inflow reach of the main stream of Huaihe River to Hongze Lake is relatively less and the decreasing amplitude of the water level at Wujiadu is not so significant．