Land-Saving Incremental Costs And Benefits Research Of Green Residences Based On System Dynamics

As the largest developing country in the world, China has been implemented the extensive mode of economic growth which depended on the increase of investment and material input for a long time,the contradiction between economic development and resources environment is much sharper than that of the most developing countries.However the resource of land is very limited in our country,the urban construction land occupied a large number of high-quality farmland for a longtime, the phenomenon of extensive use of urban stock land,and new construction land,inefficiently use and the urban ecological environment degradation exists at the same time,the conflict between the expansion of construction land and promotion of the ecological environment sustainable development with land saving has becoming more and more serious. "Green building" is the concept which produced by the combination of the idea of sustainable development and building products.In order to realize the sustainable utilization of land resources, we must carry out the research on green building land-saving and the evaluation of saving land is the premise of land-saving.At present, there are few studies on the direct economic benefit of green building for land saving in China.The existing research can not fully demonstrate the economic efficiency of land saving, which is particularly detrimental to the application of saving land technology and the realization of land saving.Starting from the incremental cost effectiveness and whole life cycle of green building,the paper discusses the composition of the whole life cycle cost of land saving technology.Through the analysis of the green residence land saving technical measures of Gansu Province,quantitative analysis the incremental cost and benefit of the green residence land saving technology and establishing the incremental cost benefit estimation model of green residence land saving.Based on the system dynamics model, comprehensive analysis the internal structure and external influence factors of the incremental cost and benefit of green residence land saving,and then establishing the incremental cost and benefit system model of green residence land saving.Finally, empirical test on the data of green housing project of Country Garden in Lanzhou.The results show that the system dynamics method is effective on simulation development of the cost and benefit of the land saving.According to the simulation results, the main conclusions are as follows:(1)Using the system dynamics model analysis the change law of incremental costs and benefits of the green residence land saving in the whole life cycle.The curve shows that the incremental cost of green residence land saving is one-off and obvious, but this does not mean that the cost increases in the whole life cycle;Because of the characteristics of the harmonious relationship between human and nature, the economic benefit of the land savingtechnical is increasing year by year. In the end, the incremental benefit of the whole life cycle is higher than the incremental cost;(2)By contrasting the different influence degree of the incremental cost and benefit of green housing land saving technology.Underground space development and utilization technology has the most significant impact on the incremental cost and benefit of green residence land saving,it construction and installation costs constitute the key in the total green residence land saving cost, it shows the most impressive economic benefit in the operating period.Therefore, the economic analysis and cost optimization control of underground space development and utilization technology is the key to promote the application of green building land saving technology.(3)By adjusting the variables, "green rate", "water permeable ground ratio", "the ground floor area ratio",simulating incremental cost and benefit of green residence land saving under different scenarios.According to the quantitative data, it is found that the balance point of the input and output in the application of land saving technology.It is suggested that the balance point should be grasped in the economic comparison and selection of the green house in the land saving technical.The research results have reference significance for the developers to promote application for the green building land saving technical.