Study Of Cultivated Land Quality Evaluation Based On GIS

Cultivated land is an indispensable natural resource for human survival.The quality level of cultivated land has an important impact on the growth of crops.Only by accurately grasping the distribution of cultivated land quality in a region can we reasonably optimize the agricultural layout in the region and put forward reliable suggestions.At present,the operation process of cultivated land quality evaluation is complex and varied,and there is no unified standard yet.In addition,the function of related evaluation software is complex and the operation is difficult.Based on this,this paper carried out research on cultivated land quality evaluation with the support of GIS technology.The main work is as follows:(1)The basic theory and key technology of cultivated land quality evaluation are studied and analyzed.Based on the comprehensive analysis of the current methods of arable land quality evaluation,this paper selects the factor method as the evaluation method to carry out research,summarizes the operation process of arable land quality evaluation,and makes a detailed analysis in combination with the operation process.The operation process mainly includes data preparation,division of evaluation unit,selection of evaluation index,data preprocessing of evaluation unit,determination of parameter model and calculation and output of results.In addition,the principles followed and key techniques used in the process of evaluating cultivated land quality are also summarized.(2)Based on component GIS technology,the cultivated land quality evaluation information system is designed and implemented.It mainly includes four functional modules:view,map spot query,cultivated land quality evaluation and map mapping.When designing the system,the operation related to cultivated land quality evaluation is taken as an independent module,and the user only needs to operate in the order of the function of the module to complete the grading and evaluation of cultivated land quality.The evaluation module mainly includes the functions of creating evaluation unit,transforming multi-component into single component,combining micro-area,spatial interpolation,replacing surface with point,manually entering weight,calculating weight by analytic hierarchy process and evaluating cultivated land quality.In addition,the map spot query and map mapping module of the system can also assist users to complete spatial query,attribute query and thematic map mapping,so that the process and integration of cultivated land quality evaluation are realized,and the efficiency is greatly improved.(3)Evaluation of cultivated land quality in Xingyang City.In this paper,in the process of evaluating the quality of cultivated land in Xingyang City,with the support of ArcGIS software,we made the point map,soil map and cultivated land plot map of the quality survey.Combined with the general situation of the research area and related technical standards,complete the selection of evaluation indicators;Fuzzy mathematics and Delphi method are used to determine the membership function of the evaluation index.Then the evaluation system was used to complete the division of the evaluation unit,the data preprocessing of the evaluation unit(i.e.spatial interpolation and replacing surface with point),the weight calculation of the analytic hierarchy process,the normalization of the index data,the calculation of the comprehensive index of cultivated land quality and the grade division.Finally,based on the cultivated land quality grade data,the distribution map of Xingyang cultivated land quality grade was made by using the mapping module of the system.