摘要
航道整治建筑物在长江上游广泛存在,其在改变局部河段的水动力和水体理化特征的同时也会对浮游生物群落产生重要的影响.于寸滩站 11 000 m3/s流量下开展顺坝和丁坝 2 座航道整治建筑物的水动力、水质及浮游生物生物量现场监测,利用MIKE21 软件建立流场,进一步模拟不同流量下坝体前后水动力、水质、生物量的变化趋势.监测结果表明,相较于坝前,两坝体坝后流速减小,溶解氧浓度、浮游植物密度、生物量增加,其中顺坝和丁坝浮游植物密度分别增加69.39%和62.18%,生物量分别增加77.42%和56.41%.基于现场监测数据建立模型得出,4 500、11 000、39 200 m3/s流量下航道整治建筑物前后水动力、水质及生物量差异性逐渐降低,4 500 m3/s流量下整治建筑物生态效果最好.研究成果可为航道整治工程区生物的保护和生态航道的建设提供理论依据.
Abstract
Waterway regulation structures exist widely in the upper reaches of the Yangtze River,which can change the hydrodynamic,physical and chemical characteristics of water body,and also have an important impact on the planktonic communities.In this study,on-site monitoring of hydrodynamics,water quality and plankton biomass is carried out in the longitudinal and spur dike at the flow rate of 11 000 m3/s at Cuntan station.Furthermore,the change trend of hydrodynamic,water quality and biomass upstream and downstream of the two dikes under various discharges is simulated using MIKE21 software.The monitoring results show that compared with the upstream of the two dikes,the flow velocity in the downstream of two dikes decreases,and the dissolves oxygen concentration,phytoplankton density and biomass increase.The phytoplankton densities of the longitudinal and spur dike increase by 69.39%and 62.18%respectively,and the biomasses increase by 77.42%and 56.41%respectively.Based on the field monitoring data,the model is established.The differences in hydrodynamics,water quality,and biomass gradually decrease at 4 500,11 000 and 39 200 m3/s flow,and the ecological effect of renovation buildings is the best at 4 500 m3/s flow.The research results can provide a theoretical basis for the protection of organisms and the construction of ecological waterways in waterway regulation project area.
基金项目
国家自然科学基金(52279058)
重庆市自然科学基金(cstc2021jcyjjqX0009)
长江航道局科研项目(KY2022-01)
水利水运工程教育部重点实验室开放基金资助项目(SLK2021B10)
维普
万方数据