Drought and Flood Variations and Rationality of Land Use in Honghu Lake During the Last 50 Years

摘要

With the global climate change, the increasing economic activity and excessive development in recent years, the climate ecological environment of Honghu Lake changes with frequent occurrence, sharp reversal of flood and drought and the atrophy of the natural lake, which lead to loss or degradation of partial functions of the lake. How to rationally develop and protect the lake and its surrounding land resources has become a very urgent task. According to the climate data and the hydrological data in Honghu area in recent 50 years, land use change in recent years, effect on water level and utilizable precipitation because of different land use and the change characteristics of precipitation and drought of Honghu were analyzed. Analyses show that the precipitation increased in Honghu region in recent 50years, especially the heavy precipitation, so that the proportion of heavy rain to total precipitation and the concentration degree of heavy precipitation increase, which lead to increase of flood. With the increase of economic activity, land use changed greatly. Farmland area decreases and aquaculture area increased 6-7 times nearly 20years. Aquiculture area of three surrounding counties equals to 2-3 Honghu Lake area in 2010. Agriculture and fishery need great deal of water from April to May, which is the main reason for more disasters in drought year and ecological functions destruction of Honghu wetlands.