Study On Optimization Of Regional Land Use Structure And Layout Based On The Uncertainty

Presently,rapid urbanization and industrialization still needs a certain farmland being into non-agricultural for support,but the population and other factors make the demand of food increasing,and at the same time,the resources and environment worsening aggregately.In future,the limited land resources will be used not only for food production,but also for the economy development,at the same time used for ecological construction,so the scientific and reasonable land use planning which is to allocate land resources among different authorities is the key to realize the sustainable development.China has formulated three rounds of land use planning in nationwide range,but there is a common problem in its implementation evaluation results that is the expectation of planning is deviated from the reality,the provisions planning index has been constantly breakthrough and the planning content also unceasingly been denial.One important reason of the above negative results is the shortage considering of uncertainty in future land use optimization.The main most characteristic of planning is its future orientation,and the future always uncertain,so planning is born with uncertainty.The neglecting of uncertainty in land use structure and layout optimization makes planning policy less scientific then cause the planning failure.The root cause of flexibility is the future uncertainty,while the elastic also is to deal with the uncertainty,but at present land planning flexibility is insufficient,then making the land use planning constraints too closely and changed frequently,so the planning failures.Therefore from the perspective of uncertain,with the comprehensive consideration of future uncertainty,it can improve the scientific of land use structure and layout optimization and make results of planning policy identical to the most possible scenarios.Based on the uncertainty optimization,it can estimate elastic space size,which could improve the land use planning flexibility and strengthen the planning vitality.There is already a certain research about other resources and environment optimization based on the uncertainty,and uncertainty planning research is in its ascendant in mathematical field.From the unsure angle this paper optimizes land use with uncertain mathematical method,then developing a new perspective of land use optimization field.Firstly this paper examines the source,types and characteristics of uncertainty in land use optimization;secondly it calculates the land use optimization structure when uncertainty factors are the most likely to occur and the elastic interval of optimization structure when uncertainty factors are in a certain possibility range respectively with expected value optimization model and linear interval optimization model;and then it allocates the most likely optimize structure and the land use structure elastic interval in space with CLUE-S model in order to reach the layout optimization purposes;at last it takes Yangzhou as an example for empirical research and its main research contents and methods is concretly in the following:1?Investigation of land use optimization uncertainty.It will investigate the sources and the properties of land use optimization uncertainty from land use optimization concept as a starting point in order to make clear the research object of this paper.At last of this part,corresponding measures to treatment land use optimization uncertainty is put forward to be the foundation for the below.2?Calculation of the maximum possible optimized structure in uncertain environment.According to the historical sequence of uncertain indexes,of which target value is forecasted with the gray model;after that,the second part is to investigate and statistic the possible changes and distribution of uncertain indexes around the predicted value;thirdly with the Law of Large Numbers,distribution information of uncertain index is embedded into the expected value model,which is calculated by multi-objective genetic algorithm and the algorithm is realized in Matlab programming.3?Calculation of the land use structure elastic interval when the uncertainty is in a certain possibility range.It calculates land use structure corresponding by the best optimum value and the structure corresponding by the worst optimal value with using the interval optimization model according to uncertain index change interval,on the basis of that it could estimate the land use structure elastic interval when the effective vector density of interval is up to a certain standard with computer program.4?Land use layout optimization when uncertainty factors are in the maximum possibility.This part makes the optimal land use structure under uncertain environment allocated in space,which is first to optimize the present situation and adjust the unreasonable layout,and second is to extract distribution rule of different lands from the optimization of the status map,then with it as criterion,land use optimized structure when the uncertain factors are most likely occurred is configured in space with CLUE-S model.5?Partition of land optimization layout elastic space.This part firstly infer the land structure situations when different land types take its upper limit value and lower limit value;then making land structures corresponding to the upper and lower limit values as quantity requirements in the CLUE-S,by which spatial configuration are finished.For some land use type,above two simulations may have different places,and which is exactly elastic space of this land type.For there is overlapping part during different land use elastic space,the paper taking suitable probability for different types as criterion,make the overlap configuration into the type whose suitable probability is higher,thus different elastic space of each types combined could form the land use layout elastic space.Through the study,this paper concludes that:1?The land use optimization is in uncertain environment,and there is much uncertainties.Making the planner as boundary,the uncertainty sources can be divided into external and internal sources.The internal environment uncertainty mainly is the model uncertainty and planner uncertainty and external uncertainty mainly is the foundation uncertainty,economic uncertainty,social uncertainty and ecological uncertainty.Measures dealing with land use optimization uncertainty include that is to collect land demand information extensively for making the future uncertain information manifest as far as possible,to apply unsure mathematical model for calculating the most likely optimization results,to formulate the flexible land use planning for reserving a certain space for uncertainties.2?The key of land use structure optimization based on uncertainty is to identify the distribution and changes of unsure index and to embed the uncertain index into the optimization models.The uncertain index is no longer the only predicted value,but is the variable having a certain probability distribution,because it represents the size and possibility of uncertain influence,so the key is to seek its distribution information.Embedding uncertain index into optimization model is also an important matter,for the unsure index distribution representing its information level,so whether it is well embedded represents if the information can be made full use by optimization model.3?Elastic interval is the external performance caused by uncertain factors to the land use.The flexibility is caused by uncertain factors of land use optimization.The optimization scheme will not only,because land use may has much uncertainties in the future,so optimization scheme needing a certain elastic space,and the much uncertain in future the larger of elastic space.The relating influencing factors of land use optimization can be thought of independent variables to a function,and the optimization results as dependent variable,because independent variables itself is uncertain,having a certain distribution change,then the dependent variable should also be a certain change interval.4?CLUE-S model can be used for layout optimization.When using the CLUE-S to distribute land resource spatially,the future layout is decided by current situation of the overall layout.If present situation is optimization level,the future layout will also being optimization,if current situation has shortcoming,the future layout will also not be reasonable.So this paper firstly optimize the current situation,after that extracting optimization distribution rules from the present situation map optimized,with which as guidance to optimize the future land use layout.5?Uncertain mathematical model can be used for the land use optimization under uncertainty environment.Definitive environment is relative,while the uncertain environment is real,to pursue more realistic resource allocation scheme,uncertain mathematical model is ascendant to used in the study of the optimal allocation of water,electricity,oil and other resources.Uncertainties also existing in the area of land use,and land use optimization also faced with uncertain environment,so with uncertain mathematical model for optimal allocation of land resources,scientific of land use optimization scheme can be improved and to promote the utilization of the sustainable target of land use.