论文部分内容阅读
针对长江与鄱阳湖复杂的江湖关系,立足于“湖补江”、“湖分洪”等水量交换过程,基于概念解析、方法定义等手段,提出了顶托强度指数、倒灌强度指数及水量交换系数的概念和计算方法,定量表征了长江与鄱阳湖间顶托、倒灌、“湖补江”、“湖分洪”等水量交换相互作用及年内变化过程,并利用了TFPW-MK和MK趋势分析法研究了水量交换年际变化趋势,从流域来水差异、三峡水库调度及湖区水位容积变化角度,探讨了驱动江湖水量交换效应变化的机制及量化影响.研究成果表明:综合影响下鄱阳湖汛期7~9月多年平均顶托强度27.5%,时常发生倒灌现象,平均倒灌强度8.3%,水量交换以“湖分洪”状态为主;枯水期12~4月多年平均顶托强度8.8%,水量交换以“湖补江”状态为主.2003年三峡水库运行调度以来,增加了长江中下游干流12~3月流量,湖口顶托强度增加6.0%;汛期削峰作用降低湖口顶托强度4.8%,倒灌强度减弱2.3%.近20年来鄱阳湖湖区容积变化导致多年平均顶托强度降低0.14%.长江与鄱阳湖流域来水差异是直接驱动江湖关系变化的主因.本文加深了对通江湖泊水量交换机理的认识,研究成果可为鄱阳湖湖泊综合治理提供借鉴.
Aiming at the complex rivers and lakes relationship between the Yangtze River and Poyang Lake, based on the process of exchange of water such as “Lake uptake”, “Lake diversion” and so on, based on concept analysis and method definition, the top-off strength index, And the concept and calculation method of water exchange coefficient, quantitatively characterize the water exchange interaction and annual variation process between the Yangtze River and Poyang Lake, such as top-supporting, intrusion, “lake uptake” and “lake diversion” TFPW-MK and MK trend analysis to study the interannual variation trend of water exchange, and discuss the mechanism and quantitative impact of changes in driving water and river exchange effect from the angle of water coming from the basin, the Three Gorges Reservoir and the change of water volume in the lake area. : Under the comprehensive influence, the average annual stand-off strength of Poyang Lake from July to September of 2007 was 27.5%, the phenomenon of intrusion often occurred and the average backfill intensity was 8.3%. The water exchange was dominated by “lake diversion” and the dry season averaged from December to April The top-level strength is 8.8%, and the exchange of water volume is mainly in the state of “lake replenishment.” Since the operation of the Three Gorges Reservoir in 2003, the flow rate of the main stream in the middle and lower reaches of the Yangtze River increased from 12 to March, Chipping effect reduces the lake The top-supporting strength is 4.8% and the under-pouring intensity is weakened by 2.3% .During the past 20 years, the change of the volume of the Poyang Lake Basin leads to a decrease of 0.14% in average annual stand-off strength.The difference between the Yangtze River and Poyang Lake basin is the main cause of the direct driving changes in the relationship between rivers and lakes. The understanding of mechanism of water exchange in Tongjiang Lake can provide reference for the comprehensive management of Poyang Lake.