Allocation Of The Increment Of Urban Construction Land Based On Suitability Assessment

At present,China is in the primary stage of socialism.High-speed urbanization and industrialization brings the continuous expansion of construction land,especially urban construction land.The expansion of urban construction land is still with the extensive type in our county now.The blind expansions of urban construction land results in a large amount of farmland and ecological land invaded and sustainable development of economy,society and ecosystem facing severe challenges.To ensure the improvement of social and economic healthily and continuously,traditional land use patterns of China must be changed,which are influenced by the characteristics of the stages of social and economic development and particular national conditions of resources.Construction land expansion must set caps and be strictly put under total quantity control.Reasonable allocation of the increment of urban construction land is one of the important contents for drawing up land use planning.Suitability assessment of urban construction land is a good way to judge if one particular piece of ground is ready to be used as urban construction land.It can help us know spatial disparity of land which is suitable for urban construction land spatial disparity and offer reasonable basis for optimizing the layout of urban space,choosing the direction of urban construction land expansion and exploring the new space for urban construction land.Moreover,suitability assessment of urban construction provides a reference for valuing and making rational use of land,solving the problem of construction land increasing and tillable land decreasing and realizing the balance of ecological environment.Under the premise of incremental control of urban construction land,allocating the increment of urban construction reasonably with the result of suitability assessment can avoid using land blindly and realize ideal extension of urban construction land.This research is based on summarizing and concluding research results of prediction of suitability assessment of urban construction land and allocation of urban construction land.Under theory system instruction of landscape ecology and theory of sustainable development,the paper analyses the affect factors of suitability of urban construction land firstly,then builds the model of suitability assessment of urban construction land based on BP neural network which is based on study of index system of suitability assessment of urban construction land and classification standard of suitability grades of urban construction land.Secondly,under the premise of incremental control of urban construction land,this paper makes rules for allocating the increment of urban construction land with the results of urban construction land suitability assessment and principles of the layout of urban-rural construction land,then makes a reasonable plan of allocation of the increment of urban construction land.Considering scale control and spatial layout of the increment of urban construction,the paper makes suggestions to optimize allocation of the increment of urban construction land and builds the policy system of the optimum allocation of the increment of urban construction land.The result shows following points:(1)The suitability assessment of urban construction land based on BP neural network can improve precision of the suitability assessment results of urban construction land.And it will definitely provide scientific and exact data support for planning of the newly added urban construction land allocation.(2)Rules for allocating the increment of urban construction land with the results of urban construction land suitability assessment and principles of the layout of urban-rural construction land can guide the rational allocation of the increment of urban construction and provide a reference for the reasonable layout of the urban construction land in land use planning project.(3)The policy system of the optimum allocation of the increment of urban construction land is built.Optimizing allocation of the increment of urban construction land need start with two aspects,scale control and spatial layout of the increment of urban construction.