Research On Eco-environmental Water Demand Of Lake Wetlands In Lixiahe District

Lixiahe District lies in the middle part of Jiangsu Province, between Yangtze River and Huai River at 119°08′～120°56′N, 32°12′～34°10′E. For the district is in themiddle latitude region and faces the Huang Sea on the east, the winter and summer monsoons flow over the whole area and bring abundant rainfall. The midland of the district is low-lying and is the famous flood corridor in the history. Lake wetlands, as special water-soil resources, are the natural waterlog water storages and can regulate 60% of the rain waterlog runoff yield. However, for a long time the area of lake wetlands shrank, the storage capacity fell off and the flood and drought preventing function was impaired. Nowadays the function of the lake wetlands received more and more consideration. In this paper, with the support of Jiangsu Water Conservancy Technology Key Item (2004216), systemic researches of the lake wetlands in the district were discussed and the reference for the water plan and the water resources adjustment were provided. Main contents are as following,(1) The soil utilization structure of the district was analyzed by the TM resources of the year 1985, 1995 and 2000. Through investigation of eco-regeneration process of the lake wetlands, the effects of the area decrease of lake wetlands on natural disaster, water conservancy, biology diversity and the economic development were analyzed by correlation and grey rational analysis methods. In the district, the lake wetland inning got economic advantage by sacrificing the ecology diversity and the human living space. So the thought of resolving the water problem by engineering measures should be changed and the simplifying trend of the biology species controlled to make sure the continuable utilization of the lake wetlands.(2) The calculation methods of eco-environmental water demand of lake wetlands in Lixiahe District were discussed. Dazong Lake was selected as a typical area and each grade of eco-environmental water demand was calculated and analyzed. The water demand of Lixiahe District was calculated according to the different functions of the wetlands and provided suggestion for the water allocation.(3) The ecological protection program of lake wetlands were made and water consumption of the year 2020, 2030 and 2050 was forecasted. And it was proposed that...