A study on system dynamics model in eco-environment planning for Da''an of Jilin Province
吉林省大安市生态环境规划系统动力学仿真模型

As the basic condition of exist and development of human being, environment is the physical base of the development of economy and society. How to protect and construct environment, and how to utilize natural resources reasonably are the problems we have to face. In view of the salinization in the western of Jilin province, soil, forest and water should be under controlled synthetically. Agroecological environment is a multi-target, multi-variable, multi-loop, nonlinearity feedback system. An integrated approach, system dynamics(SD), is applied to solve the eco-environment planning in this paper, the city of Da'an has been taken as a case to be studied. SD is a new method in system analysis in modern times, while it has been increasingly used in solving many problems in recent years, such as sustainable development, eco-environment system, water resource carrying capacity, soil and water conservation, and so on. It is a simulating technique used with computer to simulate dynamic behavior of society, economy and environment, and a useful tool of scientific prediction. On account of the complex and fragile environment, a model with system dynamics theory was established in the paper at first. It consisted of modules about population, land, planting, stockbreeding, environmental benefit and economy, which were integrated with a group of dynamics equations such as level equation, rate equation, assistant equation, etc. The program was written by DYNAMO language. System action at varying development schemes could be got through inputting original data and various velocities of variables. Finally, the model was applied to study eco-environment planning in Da'an of Jilin province, and the related indices in different schemes are obtained, from which the best scheme was put forward to coordinated development of society, economy and environment. Comparing SD to other methods in studying agroecological eco-environment planning, different schemes are easier to get, the calculation is much more reasonable, and it can be factually simulated that the harmonious development status among society, economy and environment. Thus SD is an innovative and maneuverable method which can be used to study eco-environment planning.