基于GIS的华池县耕地生产力分级评价与属性分析

Evaluation and Analysis for Cultivated Land Productivity Based on GIS in Huachi County

以土壤图、土地利用现状图、行政区划图和地貌类型分区图叠加形成评价单元,选取对研究区耕地生产力影响较大、与农业生产有密切关系,并且具有区域差异明显、时间序列上相对稳定特征的11个因子,建立了评价指标体系。应用层次分析法,通过综合分析,将华池县耕地共划分为5个等级。结果表明:华池县总耕地面积为6.89万hm^2,其中二级、三级、四级生产力耕地占的比例较大,分别为19.1%、35.1%和28.9%,占总耕地的83.1%;一级生产力耕地和五级生产力耕地占的比例较小,分别为5.8%和11.2%。其中高产田地土壤主要黑以垆土和淤积土为主,土壤质地构型以均质中壤和壤身中壤为主,地貌类型主要为川台地和塬地为主,灌溉保证率好,灌溉水质好,地势平坦,无明显障碍层,土壤理化性状良好,可耕性强,土壤肥力高;低产田地土壤以黄绵土为主,红土面积较少;地貌类型以北部高山丘陵区、南部丘陵区、子午岭丘陵区分布广,川台地和塬地面积较小;土壤质地构型以均质中壤为主,壤身轻壤和壤身中壤类含量较少。

With soil map,land utilization map,administrative zoning map and geomorphic type map as the evaluation units,11 variables which were closely related to agricultural production with obvious regional variation and stable time sequence were selected to establish the evaluation index system. Hierarchy analysis processes were applied and comprehensively examined. Results showed that the total 68 900 hm^2 of arable land in Huachi county could be divided into five grades. Majority of the cultivated land fell into the second-,third- and fourth-grade with 19. 1%,35. 1% and 28. 9%,respectively,accounting for 83. 1% of the total arable land,while the first grade and fifth-grade land accounted for 5. 8% and 11. 2% respectively.