Study On Sustainable Land Use Evaluation And Countermeasures Based On Emergy Analysis

With China's rapid economic growth and rapidly increasing urbanization level, contradictions among population, resources, economy, and environment become increasingly prominent. Due to the limitation of land area and supply of natural and economic, unreasonable land investment and land use, one-sided pursuit of social and economic benefits and inadequate consideration of the maintenance of the ecological environment of land in some areas have resulted in reduction of cultivated land, decline in the quality of land resources and ecological environmental degradation, which hindered the implementation of regional sustainable development. To this end, studying the current evaluation and path construction of sustainable land use and exploring how to maintain harmonious man-land development and reduce pressure on land ecosystem has important significance of realizing regional sustainable land use and ensuring stainable social and economic development.This paper selects Wuhan city as object of study, analyzes and evaluates sustainable level of land use system in Wuhan on perspective of the emergy analysis, then it explores ways and means of rational and sustainable land use. On the content and methods in the paper, it firstly introduces emergy analysis, studies the operation of land eco-economic system from 1996 to 2008 and preliminary judges its sustainable level in Wuhan. Secondly, it determines the evaluation target, establishes evaluation index system of sustainable land use on the basis of emergy analysis indicators and evaluates sustainable level of land use by using T-S fuzzy neural network. Thirdly, it uses mean impact value(MIV) method based on BP neural network to find the relative contribution and direction of each index to system deviation, and analyzes the factors of sustainable land use in Wuhan from the two aspects of obstacles and drivers. Finally, for land use characteristics, problems and the factors affecting the sustainable land use, this paper puts forward Corresponding countermeasures and suggestions.By studying, we find that deviation of land use system rose to 0.3802 from 0.0347 and optimization level decreased from 1.4678 to 1.4256 after 2005 in Wuhan, the sustainability of land use system has cut down. The increasing of fossil fuel consumption, environmental loading rate of land, as well as waste energy of unit of land area and input of non-renewable resources energy of unit of land area gradually constitute obstacle factors which impede sustainable development of system. At the same time, the reduction of emerge emergy of waste rate year by year, enhanced population carrying capacity and the growth of renewable resources input of unit of land area constitute the drivers which can promote sustainable development of the system. Based on this, this paper proposes suggestions of changing resource input structure, optimizing the industrial structure, protecting the quantity and quality of cultivated land and controlling strictly new construction land in order to provide a scientific basis for the management of sustainable land use and urban development planning.