Evaluation Of Land Resources And Environmental Carrying Capacity Based On System Dynamics

The rapid development of social economy has caused many environmental problems,such as land desertification,air pollution and so on,which makes the contradiction between resource supply and environmental capacity become increasingly prominent.In order to promote the sustainable development of our society,the government has issued a series of documents to strengthen the protection of the ecological environment.Among them,the evaluation of land resources and environmental carrying capacity is to carry out the compilation of land space planning It’s an important work for us.By evaluating the carrying capacity of land,resources and environment,we can judge whether the regional socio-economic development and the allocation of resources and environment are reasonable,and reveal the main limiting factors affecting the improvement of carrying capacity,so as to provide theoretical and decision-making basis for land spatial planning.At present,there are few researches on small-scale carrying capacity of county,so thesis mainly uses the method of system dynamics to evaluate and simulate the carrying capacity of resources and environment in Weng yuan County,so as to provide decision-making reference for land and resources management.Firstly,thesis reviews the research progress of resource and environment carrying capacity at home and abroad,and summarizes the concept,evaluation index system and evaluation methods of resource and environment carrying capacity.Secondly,taking Weng yuan County as an example,combined with the double evaluation guidelines,this paper carries out single evaluation and Analysis on the impact factors of resource and environment carrying capacity in the study area,and selects 19 indicators to build the evaluation system according to the actual situation of the study area Finally,the resource and environment carrying capacity system is divided into three subsystems:water and soil resources,ecological environment and social economy,and the system dynamic method is used to establish the model of Weng yuan County’s land,resources and environment carrying capacity system By adjusting and controlling the parameters of each state variable,five different economic development models are set up,which are status continuity,economic priority,resource intensive,environmental protection and comprehensive coordination.The evolution trend of resource and environmental carrying capacity in the study area from 2019 to 2035 is simulated,and the best scheme suitable for the development of the study area is analyzed,and the Countermeasures for improving the resource and environmental carrying capacity are put forward Suggestions.Based on the double evaluation guidelines,the natural factors affecting the carrying capacity of resources and environment in the study area were evaluated and analyzed in a single way:(1)the land resources carrying capacity of Weng yuan County was revised and evaluated by integrating the three factors of slope,elevation and topographic relief.The results show that the spatial distribution of land resources carrying capacity in Weng yuan County is quite different,but the overall carrying capacity level is higher,and it is distributed in the gentle terrain In the central and eastern region,the land area with low carrying capacity and below is relatively small,which is distributed in the rugged mountainous areas in the north and southeast of the county;(2)the annual average precipitation in the county is more than 1200 mm,and the available water resources are extremely rich,with sufficient water supply,which has high water resources carrying capacity;(3)the county is mainly located in the subtropical region,with the same season of light and heat,and has high water resources carrying capacity;(4)the results show that the overall air quality of Weng yuan County is good,and the inhalable particulate matter is the main air pollutant at present.Due to the serious water pollution,the water quality standard rate of the internal water distribution functional areas in the county is low,so the water environment carrying capacity is low;(5)the extremely important areas of soil and water conservation in Weng yuan County are mainly distributed in the areas with large slope and high vegetation coverage in the northwest,and the county belongs to the county In the hilly area,the phenomenon of soil erosion is more common,and its sensitivity is mainly moderate and severe.Based on the systematic analysis of the influencing factors of the carrying capacity of the study area,19 indicators were selected to build the evaluation index system,and the system dynamics model was established to comprehensively evaluate and dynamically simulate the current situation and future development of the carrying capacity of the study area.The results show that:(1)the overall trend of the comprehensive carrying capacity of resources and environment in Weng yuan County from 2009 to 2018 is fluctuating upward,and the index of the carrying capacity is stable(2)among the five economic development plans,the carrying capacity of resources and environment under the current situation continuation plan is higher than that under the current situation intensive plan,which decreases first and then increases,while the carrying capacity of resources and environment under the economic priority plan and environmental protection plan is gradually increasing,but its growth rate is slow Therefore,from a long-term perspective,the comprehensive coordinated development plan is the most ideal development plan for Weng yuan County in the future.In the process of economic development in the future,we should pay more attention to the overall coordination of population,resources,environment and social economy.