引用本文: | 姚静,李云良,李梦凡,张奇.地形变化对鄱阳湖枯水的影响.湖泊科学,2017,29(4):955-964. DOI:10.18307/2017.0419 |
| YAO Jing,LI Yunliang,LI Mengfan,ZHANG Qi.The influence of bathymetry changes on low water level of Lake Poyang. J. Lake Sci.2017,29(4):955-964. DOI:10.18307/2017.0419 |
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摘要: |
基于2010年鄱阳湖最新地形,构建精细的鄱阳湖二维水动力数学模型,相同网格下构建1998年地形,分别模拟不同地形条件下2006年枯水年水位、流量时空分布,分析地形变化对水位、流量的影响,阐释地形影响的时空差异. 结果表明:相比1998年,2010年地形由于北部入江通道的下切,相同的2006年水文条件下,水位普遍降低;水位越低,上下游水面坡降越大,受地形影响越明显;低水位最大降幅1~2 m,而高水位最大不超过0.4 m,分别对应湖口9 m以下、15 m以上水位;地形对水位的影响程度都昌 >星子 >棠荫 >康山;都昌至湖口段水头差降低了2 m,水面坡度变缓,棠荫至都昌段水面坡度变陡,康山至湖口水头差基本不变;全年出湖总流量增加了6%;地形变化影响最显著为河道区,影响范围可波及大部分湖区,局部地形的变化使得子湖水面积也存在一定差异. 本研究首次基于水动力模拟量化了鄱阳湖地形变化对水位的影响程度和范围,结果可为水资源管理、江湖关系演变分析、湿地生态环境保护等提供科学参考. |
关键词: 地形变化 水动力模拟 低水位 鄱阳湖 |
DOI:10.18307/2017.0419 |
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基金项目:国家重点基础研究发展计划(2012CB417003)、江西省重大生态安全问题监控协同创新中心项目(JXS-EW-00)和国家自然科学基金项目(41301023,41371062)联合资助. |
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The influence of bathymetry changes on low water level of Lake Poyang |
YAO Jing1, LI Yunliang1, LI Mengfan1, ZHANG Qi1,2
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1.Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, P.R.China;2.Key Laboratory of Lake Poyang Wetland and Watershed Research, Ministry of Education, Jiangxi Normal University, Nanchang 330022, P.R.China
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Abstract: |
A fine 2D hydrodynamic model of Lake Poyang was used to simulate the hydrological effect of the bathymetry changes between 1998 and 2010. Spatio temporal patterns of water levels and discharge in 2006 of two DEM were simulated to assess the bathymetry effect, considering 2006 as a typical dry year. Results showed that the north water way was deeper in 2010 than that in 1998, resulting in lower water levels. In low water level period, the water surface gradient was larger, and the effect of DEM changes was more significant than that in high level period.The low water levels decreased by 1-2 m corresponding to water level lower than 9 m at Hukou. The reductions of high water levels were lower than 0.4 m when water level at Hukou higher than 15 m. The influenced magnitude was largest at Duchang, followed by Xingzi, Tangyin and Kangshan.The water head from Duchang to Hukou decreased by 2 m in low level period. The water surface gradient decreased from Duchang to Xingzi, and increased from Tangyin to Duchang. There was no distinct gradient change from Kangshan to Hukou. The total discharge into the Yangtze River increased by 6%. The channel areas were most affected, however the influence of bathymetry changes spread across the most of the lake area.Water areas of some sub-lakes varied due to the local morphological changes. This study quantified magnitude and domain of the effect of bathymetry changes on Lake Poyang level from a hydrodynamic perspective. The outcomes may provide scientific support for water resource and ecological environment management, evolution and analysis of river-lake relationship. |
Key words: Bathymetry change hydrodynamic simulation low water level Lake Poyang |