Evaluation On Suitability Of Cultivated Land Suitability Based On Weights Sensitivity For Analysis Hunan Province

Cultivated land suitability evaluation is an important part of land suitability evaluation, and thecomprehensive assessment on conditions that affect the cultivated land, clarify land property of productivepotential, as well as cultivated land suitability, restrictive and the degree of their differences in evaluation.Carrying out the land suitability evaluation can provide strong technical support and assurance for realizingeconomic, social and ecological benefits of optimization, and sustainable land use, sustainable economicdevelopment, land use structure optimized.In this paper, Hunan Province is choose as the study area, analysis and summarize of domestic andforeign research progress on the cultivated land suitability evaluation study were carried out, based on theactual situation in Hunan province, build the land suitability evaluation index system, with the support ofGIS technology, using the method of regression tree, kernel density to extract and compute the contestantfactor data, and build the evaluation factor database. Based on Multiple Criteria Decision Making (MCDM)framework, using the Analytic Hierarchy Process (AHP) to determine the weight of each contestant factor,selecting weighted superposition method for cultivated land suitability, a comprehensive analysis of thecultivated land suitability can be divided into highly suitable, moderately suitable, marginally suitable andunsuitability. Finally, in order to evaluate the uncertainty of evaluation results, weight-based sensitivityanalysis was introduced, and construct the comprehensive sensitivity evaluation index, use integration ofthe score of the average absolute change rate (MACR) to characterize the degree of sensitivity, and GIStechnology was used for visual displaying.This paper’s main conclusions are as follows:(1) Build the cultivated land suitability evaluation index system of Hunan Province. According to thesituation of Hunan Province, on the basis of the principle of index selection, to construct relative complete,multi-level evaluation system, including soil conditions, terrain conditions, climate condition, ecologicalsecurity conditions and geographic conditions five aspects of11indicators.(2) Established a comparatively complete farmland suitability evaluation factor database. Using"Regression Tree Modeling+space residual" method to obtain high accuracy accumulated temperaturedata. Applied the Revised Universal Soil Loss Equation （RUSLE）to quantitative analysis of soil erosion intensity of Hunan Province. Meanwhile, use the density of traffic network, the density of traffic network,location dominance of three aspects to build traffic advantage degree calculation model, which calculate thedensity of road network data calculation method introduced kernel density. Provide scientific data basis forthe further cultivated land suitability evaluation in Hunan Province to(3) Using the Analytic Hierarchy Process (AHP) to calculate the weights of each factor and thequantitative classification of these factors. By calculation, the effective thickness of soil layer for maximumweight of0.1792, followed by slope0.1719.Reference to the research results and related technicalregulations of other scholars, classification for each contestant factor to quantify.(4) Cultivated land suitability evaluation., GIS-based spatial analysis techniques and weightedsuperposition method were used to obtain comprehensive cultivated land suitability evaluation results, andthrough the natural interval classification evaluation results will be reclassified as: highly suitable (S1),moderately suitable (S2), marginally suitable (S3), unsuitable (N) into four categories, the proportion was:24.34%,27.7%,32.35%,15.61%. Overall, cultivated land suitability distribution demonstrate that" high in the east and low in the west ", high suitability area of arable land mainly in the North of DongtingLake Plain and the Xiangjiang River plains,; followed in the Hilly Region Basin, marginally suitablecultivated land suitable and unsuitable areas are mainly located in Western, Northwestern and Southernmountain of Hunan.（5）Based on the sensitivity analysis of weights. This study draws the weight sensitivity analysismethod into cultivated land suitability evaluation, and with sensitivity analysis of former studies lackspatial information expression and mining of the evaluation result, by building a comprehensive sensitivityevaluation refers to the suitable assessment-scoring average absolute change rate (MACR), test thecontestant indexes weights small changes (-40%-+40%, step size of2%) with the result of comprehensiveevaluation of influence degree to the evaluation result analysis. The results show that the effective thicknessof soil layer has a relatively high sensitivity on the evaluation results; MACRs values show a approximatelinear increase with the absolute value of the rate of change of the weight increase but with differentgradients for different criteria, that is, when the index weight increase or decrease by the same amount (±n%change,0≤n≤40), the degree of influence on the evaluation result is consistent; when the weightchange30%, the biggest MACR value is only1.9410%, shows that the evaluation results is relatively stable in general; but at the same time, through the analysis shows that the low suitability region has a highersensitivity. Therefore, cultivated land suitability results are robust but relatively sensitive in local areas.