Impacts of the Yangtze River Water Transfer Project on water quality of Lake Chaohu in different typical years

Abstract

“引江济巢”作为引江济淮的起始段工程，承担着改善巢湖水质的重要任务，调水路线的选取对水质改善效果有关键影响.本文基于MIKE21模型构建了巢湖水动力水质模型，分别模拟了丰水年、平水年和枯水年情景下巢湖流场和总氮、总磷浓度时空分布特征，以及不同调水路线在各典型年对巢湖水质的影响.结果显示巢湖流场和水质分布有明显的空间差异性，受入湖负荷和流量影响，巢湖在丰水年水质较差，整体来说东湖区水质优于西湖区.相比其他年份，丰水年调水对湖区水质的改善作用最明显；不同调水路线中，自白石天河入流相较兆河入流对巢湖，尤其是西湖区水质改善明显.;As the starting part of the Yangtze River Water Transfer Project, it plays an important role in improving the water quality of Lake Chaohu. The selection of the water diversion route has a key impact on the water quality improvements. Based on the two-dimensional model MIKE21, we simulated the hydrodynamic and water quality distribution of Lake Chaohu in wet, normal and dry years, as well as the influence of different water diversion routes on the water quality of Lake Chaohu in different years. The results showed that there were obvious spatial heterogeneity in the flow field and water quality of Lake Chaohu. The water quality of Lake Chaohu was poor in wet year and was better in the eastern area than that in the western area. Compared with other years, the water diversion in wet years has the most obvious effect on improving the water quality in the lake area. In different water diversion routes, the inflow from Baishitian River has significantly improved the water quality of Lake Chaohu, especially the west lake area, compared with the inflow of Zhaohe River.