Abstract

With the considerable fluctuation of China's second freshwater lake, Dongting Lake has changed its water budget. Over the last few years, many floods and water level depletion occurred; thus, the research on Dongting Lake flood prevention and control, and understanding the hydrological processes has great importance in the middle Yangtze River. In this study, MIKE FLOOD Modeling coupling one-dimensional and two-dimensional Mike hydrodynamic (1D-2D MHD) is used for simulating hydrodynamic behavior of Dontgting Lake controlled by Yangtze River and its basin. The model was employed to simulate the lake storage capacity and water budget in dry and wet seasons over the period 2011-2014. A large amount of inflow was observed in 2012, whereas in 2011 was less compare to all four years. The findings revealed that runoff from rivers(Xiang, Zi, Yuan, and Li) is dominating the lake water variation. During the dry season, the flow characteristics in the East Lake and South Lake have an obvious counter-clockwise circulation because of the influence of wind and terrain conditions. Besides, lake surface temperature is mainly affected by the air above the lake. This study results provide a comprehensive tool for lake water fluctuation and wetland management.

Keywords: Modeling; Dongting Lake Basin; Storage capacity; Numerical simulation; Water budget; Wetland management