Evaluation Of Resource And Environment Carrying Capacity Of Land Based On Principal Component Analysis And System Dynamics Model

As the social economy develops rapidly, the constraints on the sustainable development of social economy imposed by the limits of resource supplies and the environmental capacity have grown more serious. The resource and environment carrying capacity of land is an important criterion when judging the reasonability of regional social economic development and the allocations of environmental resources. It also plays a fundamental role in land resource management and land spatial planning. Besides, it is also an important consideration when measuring the harmony of the relationship between human and the land. When evaluating the resource and environment carrying capacity of land, the combination of principal component analysis (PCA) and system dynamics (SD) can help to improve the objectivity and scientificity of the evaluation results. Therefore, this paper combines these two methods to build an evaluation method for the resource and environment carrying capacity of land. And it takes Yiwu City in Zhejiang Province, which has notable contradictions between human and the land and has been one of the pilot cities of land specific reform, as an example to evaluate its resource and environment carrying capacity and to perform a simulation of its future evolution trends. This can help to enrich the evaluation theories and methods of the resource and environment carrying capacity of land, and to provide some references for decisions on resource and environment management of land.This paper firstly illustrates the research progress of evaluations of resource and environment carrying capacity at home and abroad, and defines the connotation of resource and environment carrying capacity of land and it also builds an evaluation methods of resource and environment carrying capacity of land based on the combination of PCA and SD. Secondly, on the basis of analyses on the features of the resource and environment carrying capacities in the study area, this paper builds an evaluation index system for the resource and environment carrying capacity of land based on PSR model. It then adopts PCA to filtrate those evaluation indexes and to determine their weights, and applies the vector norm method to calculate the index of the resource and environment carrying capacity of land in the study area from 2009 to 2013. Finally, on the basis of systematic analyses of influencing factors of the resource and environment carrying capacity of land in the study area, this paper builds an SD model of the capacity and examines the model’s effectiveness. It then performs a simulation of the dynamic changes of the resource and environment carrying capacity of land in different settings in the study area from 2014 to 2030 and analyzes the simulation results, and this paper further provides some countermeasures and proposals to improve the carrying capacity in the study area.The research results indicate some points. Firstly, the overall level of the resource and environment carrying capacity of land in Yiwu City is not good. Some indexes of resource and environment have reached a warming status and some even risk status. Secondly, constraints on the resource and environment carrying capacity of land in Yiwu City are mainly water supply per capita, the rate of sewage concentrated disposing, road area per capita, population gross, arable land area per capita, domestic water consumption per capita, tertiary industry proportion. The constraints imposed by resource and environment factors are serious. Thirdly, the combination of PCA and SD model offers a better effect when evaluating dynamic changes trends of the resource and environment carrying capacity of land. PCA objectively filtrates the evaluation indexes and determines their weights, and this has improved the reliability of evaluation results out of SD model. Fourthly, the comprehensive and coordinated development strategy is the best choice for future development of social economy in Yiwu City, and it is necessary to lay emphasis on the comprehensive coordination of population, resources, environment and social economy in the process of economic development.