Land Use Change Scenario Simulation Based On CLUE-S Model

Rapid urbanization makes land use/cover change, ecological environment be damaged,relationship between people and nature faces severe challenges. That land use change canalter the structure of ecosystem and has a close relationship with climate change,biodiversity, environmental protection and food security makes it an important issueconcerned by many countries. Land use/cover change is core programme of theinternational geosphere-biosphere planning and the international human dimensions programmeon global environmental change, and it is one of core themes of Global Land Plan.Deep understanding the process and cause of land use change and how natural,societal, economy factors affect land use change has a positive significance to promoteregional land resources rational utilization. By building a scientific and rational land usesimulation model and setting different land use scenarios, the study simulated land usespatial pattern of county scale and analyzed the relation between land use and each impactfactors and the land use pattern change under different policy scenario. Its results canprovide a beneficial reference and guidance for regional land resources management,ecological protection, indemnification of food security and sustainable socio-economicsustainable development.Based on GIS spatial analysis and statistical analysis, this paper adopted CLUE-Smodel, an advanced land use change simulation and spatial modeling framework, takingLulong County in Hebei Province as an example, simulates land use data in2013on thebasis of current land use of2009. And the simulation result was confirmed to be generallyaccurate using Kappa indices with current land use of2013. Then three modes of land usepolicy scenarios were assumed to simulate land use pattern of Lulong County in2020:1)development following existing trends;2) under a strict basic farmland protecting control;3) under an ecology protecting control.The results showed:(1) The cultivated land flowed out127.11km2during2009-2013. They mainly flowedto garden plot, other land and construction land, whose areas were35.63、20.71、51.35km2respectively and they took84.73%of the total flow out areas. The construction land flowedout39.42km2and mainly changed to cultivated land. The area was31.02km2and took78.69%of changed areas. The other land flowed out115.94km2and they mainly changedto cultivated land and forest land, whose areas were60.10km2and26.85km2. The other land, garden plot and construction land were the main sources of cultivated landsupplement and it took81.94%of the total supplement areas and their areas were60.10km2,32.18km2and31.01km2respectively. Construction land mainly changed fromcultivated land and took62.11%of the total supplement which area was51.35km2.(2) On the basis of land use status data in2009, the study did the logistic regressionanalysis between the land use types and their driving forces and found that they showedstrong correlation with each other. The ROC significant test showed strong fitting degreeof forest, construction land, territorial waters and other land and weak fitting degree ofcultivated land and garden plot which was mainly because there are too many fragmentedplots of and distribution of garden plot dispersed and the weak correlations between thedriving forces and them. In general, the regression results can be used to simulate thespatial pattern of land use.(3) The simulation map of land use types in2013was acquired by operating theCLUE-S model on the basis of comprehensive analysis of probability distribution of landsuitability, conversion rules and land use status. Analyze the land use status and simulationmap with GIS spatial analysis tools, the Kappa coefficient was0.8394, which proved to bea good simulation result and the model can be applied to scenario simulation.(4) According to three different scenarios, reset the land demand and conversion rulesand then got the land use patterns in2020. The results showed that:1) under thedevelopment following existing trends, construction land kept increasing quantitativelyand mainly occupied the other land and part of cultivated land which is near the townspatially.2) under a strict basic farmland protecting control, cultivated land improvedquantitatively, cultivated land near planned prime farmland zone were not occupied muchand the high quality cultivated land was protected well. At the same time, the speed ofincreasing construction land declined slightly.3) under an ecology protecting control, theecological land, including river water, tidal flat and forest land with high elevation in thesoutheast, was well protected. Quantitatively water land and forest land increase muchand tended to invade cultivated land. Construction land mainly occupied other types ofland rather than the ecological restricted area. Therefore, prime farmland protection andecological protection polices should be implemented in Lulong County to ensure the localfood and ecological security under the premise of rational area of construction land.