基于GIS县域耕地地力的等级评价

为建立一种定性与定量相结合的耕地地力评价方法,直观准确地反映耕地地力状况,为耕地资源的科学管理和可持续利用提供依据,以宁夏回族自治区永宁县耕地地力调查分析数据为基础,在GIS的支持下,采用土壤分布图和土地利用现状图叠置的方法划分评价单元,系统聚类与Delphi法相结合筛选参评因素,层次分析法(AHP)确定其权重,模糊评判法确定耕地地力等级等方法,进行县域耕地地力评价研究。结果表明,永宁县耕地总体水平较好,现有耕地共划分为1～6等,其中,一等地面积为70 585.91hm2,占耕地总面积的9.71%;二等地面积为219 047.67hm2,占30.15%;三等地面积为230 101.46hm2,占31.67%;四等地面积为132 079.65hm2,占18.18%;五等地面积为39 328.14hm2,占5.41%;六等地面积为35 502.53hm2,占4.89%。针对不同等级耕地的属性特征进行了描述性分析,指出了研究区耕地利用中存在的主要问题,并提出了一些合理利用和改良的建议。

Evaluation of Cultivated Land Fertility Based on GIS at County Level

The cultivated land fertility in Yongning County of Ningxia Hui Autonomous Region was evaluated by Delphi approach,cluster analysis,analytic hierarchy process(AHP) and fuzzy evaluation based on GIS to establish the combinative method of qualitative and quantitative for evaluating cultivated land fertility and to provide the scientific basis for management and sustainable utilization of cultivated land resources.The results showed that the fertility of cultivated land could be divided into six grades and the area of the first,second,third,fourth,fifth and sixth grades was 70 585.91 hm2,219 047.67 hm2,230 101.46 hm2,132 079.65 hm2,39 328.14 hm2 and 35 502.53 hm2,accounting for 9.71%,30.15%,31.67%,18.18%,5.41% and 4.89% of total cultivated land area respectively.The suggestions to rationally utilize and improve cultivated land resources were proposed by analyzing the characteristics of the cultivated lands with different fertility and problems in utilization of cultivated land.