摘要
长江中游通江湖泊江湖关系的核心是长江和湖泊之间的水量交换,而江水倒灌是江湖关系相互作用中强烈的长江顶拖作用的一种最直接表现.本文以1960-2007年鄱阳湖湖口水文站的实测水文资料为基础,分析和探讨了江水倒灌鄱阳湖的时序变化特征及其影响因素.研究结果表明:受差异性的湖泊流域和长江中上游来水的影响,江水倒灌的发生主要集中在长江主汛期的7,8和9三个月,其中7月中下旬、8月底至9月中下旬是江水倒灌最为频繁的时期;近50年来江水倒灌频率的年际变化总体呈长期的减小趋势,不同年代间呈现一多一少的相间分布格局,反映出江湖作用强度在年代际尺度上存在一个此消彼长的波动过程.江水倒灌及其所反映的江湖关系相互作用的演变过程,与长江流域气候波动背景下长江中上游来水和鄱阳湖流域来水量的差异密切相关.另一方面,不同时期长江中下游过水能力的变化以及人类活动影响下鄱阳湖流域来水量和水位关系的改变也对江湖关系的演变产生了一定影响.
Water exchange between the Yangtze River and the related lakes is crucial for the river-lake rela tionship in the middle reaches of the Yangtze River. Based on the observation hydrological data recorded at Hukou Hydrologic Station in 1960-2007, this study examined the temporal variation in backflow frequen cy from the Yangtze River to Poyang Lake and its influencing factors. The results indicated that backflow from the Yangtze River to P from July to September, esp oya ecia ng Lake mainly occurred during the flooding period of the Yangtze River lly during the two periods： July and late August-September. The frequen cy and water flux of backflow from the Yangtze River to Poyang Lake varied considerably during the five decades, which indicated that the interactions between the Yangtze River and Poyang Lake alternated at a decadal timescale and showed a long-term decreasing trend. Variation in backflow from the Yangtze River to Poyang Lake and the river-lake interactions reflected by it were primarily determined by the fluctuations of the climate in the Yangtze River basin~ however, changes of river-lake hydrological system under hu- man activities had significant secondary effects. In conclusion, our investigation points out that the ratio of Yangtze River discharge to water inflow from the Poyang Lake catchment shows a long-term decreasing trend in the past five decades, which indicates a decreasing effect of the Yangtze River and an increasing effect of Poyang Lake watershed on the river-lake interactions. In contrast, the sediment deposition in the middle and lower reaches of the Yangtze River plays an important role in raising water level at Hukou Hydrologic Station and increasing the blocking effect of Poyang Lake outflow. In addition, variation in Poyang Lake storage under sediment deposition and lake reclaimation have changed, to some extent, the characteristics of Poyang Lake outflow and the river-lake interactions as well.
出处
《西南大学学报（自然科学版）》
CAS
CSCD
北大核心
2012年第11期69-75,共7页
Journal of Southwest University(Natural Science Edition)
基金
国家重点基础研究发展计划(2012CB417003)
中国科学院湖泊与环境国家重点实验室开放基金(2010SKL014)联合资助
关键词
长江
鄱阳湖
江湖关系
江水倒灌
年际变化
the Yangtze River
Poyang Lake
river-lake interaction
backflow from the Yangtze River toPoyang Lake
inter-annual variation
