摘要
长江中游自然通江的洞庭湖和鄱阳湖,在长期的季风气候以及江湖交互作用下形成了相对稳定的涨-丰-退-枯季节性水位波动模式。近几十年来,受水利工程及气候变化的双重影响,两湖季节性水情均发生了显著改变。揭示和对比两湖季节性水位波动近年来的变化趋势及强度并分析其形成的可能原因,对于指导两湖地区的湖泊管理与实践,理解长江中游江湖关系演变现状具有重要意义。基于此,以2003年为断点(即1980~2002年与2003~2014年两时段),首先通过湖区多站点水文要素的单因素方差分析揭示两湖各自的季节性水情变化特征;然后通过两湖季节性水情变化状况的对比,分析长江中游大型通江湖泊水情变化的规律及其形成原因。得出的主要结论如下:(1)2003年后,涨水期和枯水期的两湖水情均呈偏枯趋势,且水位降幅均在由上游到中游的过程中扩大,由中游到下游的过程中减小,甚至涨水和枯水期的洞庭湖下游湖区还出现了水位的小幅抬升。(2)2003年后,丰水期和退水期的洞庭湖偏枯趋势呈现不同的空间分异,丰水期的洞庭湖水位下降程度在上、中游湖区更为剧烈,而退水期的水位下降程度在中、下游湖区更为剧烈。与此同时段的鄱阳湖偏枯趋势在丰水期和退水期均在由上游至下游的过程中增加。(3)2003年后的洞庭湖水位降幅在各个季节各个湖区均显著小于位于其下游的鄱阳湖。江湖关系对两湖及其不同湖区的作用方式和强度的差异是造成两湖季节性水情演变差异的主要原因。
Due to the effect of monsoon climate and river-lake interactions, a seasonal water-level fluctuation pattern, i.e.rising seasons, flooding seasons, retreating seasons and dry seasons appearing consecutively, has been formed in the two river-connected lakes, the Dongting Lake and the Poyang Lake. In the recent three decades, dramatic changes occurred in these two lakes due to climate variation and built dams on the main stream of the Yangtze River. The Dongting Lake and the Poyang Lake are both located in the south of Yangtze River with similar climates, and probably with rather similar drainage structures. While, the Dongting Lake and the Poyang Lake are also linked by the upstream and downstream relations. Hence, the climate variations and river-lake interactions affect water regimes of those two lakes both similarly and differently. Contrasting of water regime variation of those two lakes is conducive not only to understanding river-lake interaction in middle reaches of the Yangtze River, but also to improving lake governance. In this research, taking the year2003 as the breakpoint（There are two periods： 1980-2002 and 2003-2014）, comparative analyses were performed about the hydrological data of both two lakes and the multi-site in a single lake. How river-lake interactions affect the water regime variation in those two lakes was also discussed. The results showed that（1） compared to the former period, in both dry and rising seasons, the water level declined in the upstream region of each lake during the later period, while the lake water level fell even more in the middle region of each lake. Eventually, the lake water level rebounded decreases in the downstream region of each lake. 2） In both the flood and the retreating season, magnitudes of water level fluctuations in both lakes have changed considerably since 2003. For the Dongting Lake, the biggest water level decline in flooding season occurred at the upstream region and the middle region of the lake, while the biggest decline in the retreating season occurred at the middle region and the downstream region of the lake. Unlike the Dongting Lake, the declining amplitude of water level in the Poyang Lake expanded from the upstream region to the downstream region in both the flood season and the retreating season.（3） The water level drops in the Dongting Lake were significantly less than that in the Poyang Lake.Different mechanisms and intensity of river-lake interactions are mainly responsible for these disparity in variations magnitude of those two river-connected lakes in the middle reaches of the Yangtze River.
出处
《长江流域资源与环境》
CAS
CSSCI
CSCD
北大核心
2017年第1期118-125,共8页
Resources and Environment in the Yangtze Basin
基金
国家重点基础研究发展计划项目(2012CB417006)
国家自然科学基金项目(41571107),国家自然科学基金项目41271500~~
关键词
通江湖泊
洞庭湖
鄱阳湖
季节性水位波动
river-connected lakes
Dongting Lake
Poyang Lake
seasonal water-level fluctuations
