Study On Optimization Allocation Of Water Resources Based On Water Diversion In Xianghai Wetland

Water is the source of life and irreplaceable natural resource for human survival and social development. With continuous development of economic society and population increase, the demand for water is increasing. At the same time, the contradiction between the supply and demand of water resources has become increasingly prominent. The low water use efficiency and the irrational use of water resources have led to a global issue of common concern that how to use the limited water resources rationally and scientifically to maximize their effectiveness. The value of the ecosystem has been identified gradually, resulting in that a large number of agricultural irrigation water is transferred to maintain the healthy development of the ecosystem. How to use the limited water resources to secure the ecological water demand and minimize the loss of farmers in Irrigation District are important issues to be solved.This paper takes the process of water diversion from the Taoerhe Irrigation District to Xianghai Wetland, China as the research object to study the optimal allocation of water resources during the water diversion. According to the annual water diversion plan of Taoerhe Irrigation District and the appropriate and minimum ecological water demand of Xianghai Wetland, the year of 75% precipitation guaranteed rate is selected as the study scenario. We consider the diversion of the available water of Taoer River in priority. When the water of Taoer River is insufficient, we consider the diversion of the water of Taoerhe Irrigation District to safeguard the monthly minimum ecological water demand of Xianghai Wetland. Because it is not necessary to meet the appropriate ecological water demand of Xianghai Wetland by month, water diversion should be considered from the perspective of the minimum impact on Taoerhe Irrigation District. Based on this premise, considering the rising cost of irrigation water, crop yield reduction, crop quality variation, cultivated land area decrease for digging wells and the loss of the Irrigation District Authority, the economic loss model of Taoerhe Irrigation District is established and set as the objective function. The water-related constraints are set for the water diversion plans from May to September. The objective function is solved by the LINGO software.The results show that in the year of 75% precipitation rate,Xianghai wetland needs 201.44×106m3, 127.22×106m3 water diverted from Taoer river and 74.22×106m3 from Taoerhe Irrigation District. In order to meet the minimum ecological water demand of Xianghai wetland, 0.1443×108m3 and 0.3989×108m3 water are respectively diverted in May and June. In order to meet the appropriate ecological water demand of Xianghai wetland, 0.1443×108m3, 0.5179×108m3 and 0.0800×108m3 water are respectively diverted from May, June and September. Overall, 0.1443×108m3, 0.5179×108m3 and 0.0800×108m3 water are respectively diverted in May, June, September. No water is diverted in July and August, which results in 24.25% water deficiency in Taoerhe Irrigation District. The economic loss of Taoerhe Irrigation District caused by groundwater irrigation is 58.95 million yuan.This paper provides a potential water diversion plan from the Taoerhe Irrigation District to Xianghai Wetland for the policy makers compromising the interests of both the Xianghai Wetlands and Taoerhe Irrigation District. What needs to be mentioned is that the economic loss model of Taoerhe Irrigation District can be improved in the future research to make the results more convincing and reasonable.