Study Of The Ecological Water Demand In Haihe Basin Based On The Evapotranspiration

China has been facing increasingly serious water resources crisis, especially in the HaiBasin which plays an important role in China. A series of ecological and environmental problems come as a result of the overexploitation of water resources,such as drying up of river channel, shrinking of wetland, vegetation destruction on mountain areas and so on,it is prominent that the shortage of water resources and deterioration of wate environment , it is extremely urgent to implement water ecological restoration.The attention to this question of the all society is attacked,and it has caught wide attention from the government.Water circulation on watershed scales is a process including rainfall, runoff, evaporation, erc. Among them ,evaporation of moisture in atmospheric of different surface underlying surfaces(including soil evaporation and plant transpiration,in English, Evapotraspiration, known as ET)is the key parameters of ecological processes,and one of the most important components of water cycle research and water resources management. In the current serious shortage of water resources, it is particularly important that ET monitoring and the total control of the basin water resources management, regional planning and sustainable development.The study about ET has a 200 years'history, a series of achievements have been made. However, the adoption of the traditional method of monitoring ET has great limitations, it is necessary to seek a more efficient and viable alternative, to conduct a comprehensive, systematic, continuous monitoring ET on different scales in the region.With computer technology, satellite remote sensing technology and geographic information technologies advancing by leaps and bounds, in recent years a remote sensing monitoring ET based on the new methods and new theories have been developed. It is to calculate the value of regional ET by satellite remote sensing and model.And then, to reduce the actual water consumption by testing, evaluation and effective management and implement the efficient use of water resources for the purpose of ecological restoration.ET on the HaiBasin is researched and analyzed based on the theory of ecological water requirements in river basin; an attempt to resolve these problems is made.This Paper is composed of seven parts. The research background ,purpose and significance of the dissertation are given in the introduction.ET is introduced in the theoretical study in the second Chapter,the method and development of traditional monitoring and remote monitoring to ET is summarized.The survey and present situation of the study area HaiBasin is introduced and analyzed in the third chapter.By the use of SEBAL Model ,the value of ET of HaiBasin in 2003 is obtained in the forth chaper.With the value of ET of HaiBasin in 2003,the difference and law in time and space of the value of ET of HaiBasin is analyzed in the fifth chaper.Under the guidance of the theory of ecological water requirement of river basin,ecological water demand of ecological land in HaiBasin including mountain areas,plain river and main wetlands,etc,is calculated and analyzed in the sixth chapter. At last, research results, innovations and deficiencies of this paper, and the research progress in this field are analyzed and summarized in the Conclusion.