Calculation Methods of Wetland Ecological Water and Case Study

Wetland ecological water is what wetland needs to maintain its self-development and ensure the basic ecological functions. As a special ecosystem, wetland ecological water includes vegetation water requirements, evaporation water requirements, wetland soil water requirements, wetland creature water requirements, wild life inhabitation water requirements, and water for landscape construction, etc. So, the calculation of wetland ecological water is more complex than other ecosystems. The methods to calculate wetland ecological water by water balance were presented and the ecological water of vegetation, soil, life inhabitations et al in wetland was also discussed separately in this paper. With these methods, the ecological water in Wuliangsuhai wetland was studied in detail. Wuliangsuhai wetland includes Wuliangsuhai, the second largest fresh water lake, and its surrounding marshes in Neimengu Autonomous Region. By analysing and calculating, the results were that the ecological water was 2.93×10~8m~3 in flood season and 3.109×10~8m~3 in non-flood season, and the total ecological water use was 6.029×10~8m~3 in a year. The annual water consumption and output accounted for 12.88% of the total input water in Wuliangsuhai wetland, and 2.329×10~8m~3 water resource should be supplied to it every year. Therefore, the supplied water was not enough for the wetland ecosystem and it made water resource shortage to a crisis. Wuliangsuhai wetland lies in the middle of the Yellow River basin, where the natural environment is bad and the issues of water shortage and wetland degradation are very serious. Therefore, it is very important for the conservation and restoration of wetlands in this region to calculate the wetland water requirement by the theory of water requirement.