Study On Agricultural Land Grading Based On GIS And Fuzzy Cluster Analysis

As a requirement of land management, economic and social development,agricultural land grading is an urgent task. Most recently in China, the main referenceto the agricultural land grading system is a combination of factor method andmodification method, which comes from Agricultural Land Grading Procedures(GB/T28405-2012), issued by Ministry of Land and Resources.For this reason, relying on the research and rationale of the traditional methodand the fuzzy cluster analysis method, this essay, after careful consideration, followsthe fuzzy cluster analysis method to grade agricultural land. In detail, the essay, usingArcGIS as a tool, takes Dongfeng County, Jilin Province as an example, applyingmathematical modeling with traditional method and the fuzzy cluster analysis methodrespectively to grade the test area. After comparison of the two grading results, itdraws the conclusion as following:1. It is wise to take a fuzzy evaluation on the factors and the interrelation betweenthem with the fuzzy cluster analysis method. Also this accords with the nature of theagricultural land quality influence factors. On the other hand, it could be utilized tograde agricultural land effectively with both qualitative and quantitative test, making agood supplement to the traditional method and examining the accuracy of the gradingresult.2. Fuzzy cluster analysis, relying on the rationale of fuzzy clustering, divides themain factors that would affect the quantity of agricultural land. In this way, thestraight line transmission of the quantization error generated from the traditionalmethod would be minimized, which, to some extent, would make an advantage on thecredibility of the grading results.3. It shows that there is an88.54%consistency between the two results. It states thatfuzzy cluster analysis can not only verify the accuracy of the traditional method, butalso make a good supplement.4. Agricultural land in Dongfeng County could be graded into six levels: selecting from largest to smallest in area respectively: Level I3,300.54hectare, Level II19.297.81hectare, Level III47,205.74hectare, Level IV27,250.09hectare, Level V24,069.04hectare, and Level VI9,571.54hectare. The best quality of agriculturalland mainly emerges in the area with meadow soil, alluvial soil, and paddy soil. Thefertile mountain basin in southeast and the open valley are good representatives ofthis.