System Dynamic Analysis In Area Water Resource Carrying Capacity Study

Water Resource Carrying Capacity is related to area economic sustainable development. In this paper, after comparing the existed WRCC method, system dynamic as the main method, combining with the guideline colligate estimate method and the water supplying and requiring balance is selected. According system dynamic theory, the WRCC system is divided into 6 subsystems, including water resource system, waster water system, industry requiring water system, agriculture requiring water system, living requiring water system and zoology requiring water system. According to the relations between the subsystems, decision-making variables and tables are decided, then System Dynamic model is established which including 6 subsystems, 5 state variables, 7 tables and 27 loops.According to the situation of Hejin city, Hejin WRCC SD model is established. 10 decision-making variables are selected including the increasing rate of industry requiring water every 10 thousand yuan production value, the increasing of farmland irrigating area, the ration of farmland irrigating, the increasing rate of population, the rate changing to city, the increasing rate of soil to be moved by water, the water supply of surface water, the ratio of treated wastewater, the ratio of recycling water. The 10 decision-making variables are recognized as the WRCC guideline system.According Hejin economic and environmental situation, through changing the value of decision-making variables, three different simulation scenarios are designed. According the requirement of economized type city and "the eleventh five years" plan, the value of the decision-making variables are decided. After simulating different scenarios, the optimized scenario which can "exploit new resources and saving resources" and can keeping the sustainable development is selected.The System Dynamic, the water supply and requiring balance and the guideline colligateestimate method are combined which is trying to use in the paper. This avoids the fixing of guideline quotient, conquers the directional thinking of using no dimension value to express WRCC. The method is feasible.