地理学报 ›› 2012, Vol. 67 ›› Issue (5): 699-709.doi: 10.11821/xb201205012

• 水文 • 上一篇    下一篇

鄱阳湖流域水文变化特征成因及旱涝规律

郭华1, HU Qi2, 张奇1, 王艳君3   

  1. 1. 中国科学院南京地理与湖泊研究所, 湖泊与环境国家重点实验室, 南京210008;
    2. School of Natural Resources, and Department of Earth and Atmospheric Sciences, University of Nebraska-Lincoln, Lincoln, NE 68583-0987;
    3. 南京信息工程大学遥感学院, 南京210044
  • 收稿日期:2011-11-03 修回日期:2011-03-25 出版日期:2012-05-20 发布日期:2012-07-20
  • 通讯作者: 张奇(1966-), 男, 研究员, 主要从事湖泊流域径流量和物质通量对气候变化和人类活动的响应机制研究。E-mail: qzhang@niglas.ac.cn
  • 基金资助:
    国家重点基础研究发展计划(2012CB417003); 中国科学院知识创新工程重要方向项目(KZCX2-YW-337); 南京地理与湖泊研究所科学基金(NIGLAS2010XK02); 国家自然科学基金(41001017); 美国农业部研究项目(NEB40-040)

Annual Variations in Climatic and Hydrological Processes and Related Flood and Drought Occurrences in the Poyang Lake Basin

GUO Hua1, HU QI2, ZHANG QI1, WANG Yanjun3   

  1. 1. Nanjing Institute of Geography and Limnology, and National Key Laboratory of Lake and Environmental Studies, CAS, Nanjing 210008, China;
    2. School of Natural Resources and Department of Earth and Atmospheric Sciences University of Nebraska-Lincoln, Lincoln, NE 68583-0987, USA;
    3. College of Remote Sensing, Nanjing Institute of Information Science and Engineering Nanjing 210044, China
  • Received:2011-11-03 Revised:2011-03-25 Online:2012-05-20 Published:2012-07-20
  • Supported by:
    National Basic Research Program of China, No.2012CB417003; Key Knowledge Innovation Programs of the Chinese Academy of Sciences, No.KZCX2-YW-337; Science Foundation of Nanjing Institute of Geography and Limnology, No.NIGLAS2010XK02; Natural Science Foundation of China, No.41001017; USDA Research Project, No.NEB40-040

摘要: 本研究分析了1960-2008 年鄱阳湖流域的气候和水文变化特征,用水量和能量平衡关系解释和印证了这些特征,并由此揭示了鄱阳湖流域水文变化特征的成因及干旱和洪涝发生的规律。得到以下主要结论:1) 正常或偏湿年份鄱阳湖流域6 月份容纳水量能力已达到饱和,若6-7 月降水量超出正常年份,则流域超饱和,洪涝发生。长江中上游降水量7 月份的异常偏多会对鄱阳湖流域的洪涝起触发和强化作用。2) 鄱阳湖流域7-10 月蒸发量大于降水量,特别是7-8 月蒸发量大于降水量的一倍以上,所以若4-6 月流域降水量少于平均年同期量的20%以上,则累积效应使秋旱发生。当初冬(11 月) 降水偏少时,秋旱可持续到来年的初春,形成严重的春旱。长江中上游降水量对鄱阳湖流域的春旱没有直接影响,但7-8 月降水量偏少时则对秋旱起重要的强化作用。3) 长江对鄱阳湖流域的水文过程和旱涝的发生、发展的影响主要在7-8 月的“长江与鄱阳湖耦合作用”时期和9-10月的“弱长江作用”期。

关键词: 旱涝规律, 气候, 水文, 长江, 鄱阳湖, 江湖作用

Abstract: Observational data from 1960-2008 were analyzed to obtain the mean annual climate and hydrological variations in the Poyang Lake basin, China. These variations were explained by the surface water and energy budgets, and the characteristics of these variations and the budgets were further used to deduce the rhythms of flood and drought developments in the lake basin. Some conclusions can be drawn as follows. (1) The precipitation in the lake basin increases at a large rate from January to June, reaching the annual maximum in late June. Amplifying monthly precipitation, particularly from April to June, coupled with weak surface evaporation and transpiration (ET), saturates the soils and produces a large amount of surface runoff which raises the lake level. In July, rainfall decreases sharply with clear sky and high ET, which reduces surface runoff and reverses the hydrological processes developed in the first half of the year. These drying processes continue through October, making the basin dry again. (2) When June and July have above average monthly precipitation the lake basin becomes supersaturated, and floods develop. In such conditions, if July rainfall in the middle and upper reaches of the Yangtze River basin is above average, the Yangtze River blocking (or reversed flow) effect can trigger, intensify, and prolong Poyang Lake floods. Thus, Poyang Lake floods generally occur in July and August. (3) Because the lake basin is drying after July with strong ET, if there is below average rainfall in July and the months afterwards, ET would be greater than rainfall, causing drying. Drought could occur in fall. This fall drought can persist through the winter and into the following spring and result in severe spring drought in the lake basin. Thus, the droughts occur in the fall and spring months in the lake basin. (4) The Yangtze River effects on the floods and droughts in the lake basin are most significant during the "river-lake coupling period" from July to August. Strong effects can lead to floods in the lake basin. Lack of river effects would help lower the lake level and dry the basin, leading to drought in fall.

Key words: floods and droughts, climate, hydrology, Poyang Lake basin, the Yangtze River, river-lake interactions