Evaluation Of Cultivated Land Fertility Based On GIS

This paper takes Yuzhong County of Gansu Province as a case of study.Collect relevant maps, text information and data. Set up Cultivated land Resource Management Information System by mapgis, arcgis and other software. Delphi method with 11 elements were selected as evaluation indexes. AHP is used to determine the weight of each index, with the fuzzy evaluation method to determine the degree of membership of each index, with the additive model to calculate the Integrated Fertility Index(IFI). The total cultivated land area of Yuzhong County is 92095.58 ha which can be divided into five grades:grade one 10752.71ha,IFI> 0.8, grade two 17818.23ha, IFI between 0.67004 and 0.79984, grade three 27265.31ha,IFI between 0.5501 and 0.66997,grade four 23658.9ha,IFI between 0.528 and 0.54997, grade five 12600.43ha,IFI between 0.42985 and 0.5279,sharing each percentage as 11.68%,19.35%,29.61%,25.69%,13.7%,respectively.On soil types, the first-class are the guan yu tu and hei lu tu, the second-class distribute in the guan yu tu, hei lu tu, huang mian tu and hui gai tu.Hei lu tu and hui gai tu account for a higher proportion in the second-class, respectively 48.57% and 35.68%.The third-class land distribute in the five cultivated soils,and the hei lu tu take a proportion of 46.6% accounting for the largest proportion in the third-class area;The fourth-class land are mainly hui gai tu,which takes a proportion of 94.09%.The fifth-class land are also mainly hui gai tu,that accounte for 72.33%.The most fertile arable land is in Dingyuan town,Gaoya town,Heping town,Jinya town,Lianda village,Qingcheng town,Xiaguanying town,Qingshuiyi village and Xiaokangying village.