基于GIS的永久性基本农田划定技术方法探讨——以重庆市涪陵区清溪镇为例

On Designation of the Permanent Basic Farmland Based on GIS——With Qingxi Town of Fuling County,Chongqing,as an Example

划定永久性基本农田,是确保基本农田质量和数量的重要手段,是保障粮食安全的重要举措.本文以重庆市涪陵区清溪镇为例,从耕地的质量状况、地形条件、区位条件和政策属性出发,建立永久性基本农田决策指标体系,利用层次分析法确定指标权重,运用ArcGIS9.3获取评价因子数据,采用模糊优选模型对耕地的综合质量进行排序,最后运用GIS的空间分析和制图输出功能实现永久性基本农田划定.研究实例表明:利用层次分析法确定评价因子的权重,可以使评价结果更加科学与合理,模糊优选模型可以解决一些难以量化的问题,GIS技术在数据获取、基本农田空间定位和制图输出方面具有强大的功效.同时,本次研究成果也为乡镇尺度的基本农田划定提供了科学依据.

The designation of permanent basic farmland is a quite important method to guarantee the quality and quantity of basic farmland and the food security.With Qingxi town in Fuling County in Chongqing as an example,a permanent basic farmland decision-making index system has been established considering quality status,topographic conditions,geographical location and political attribute of the farmland.The weight of related evaluation indexes had been determined by the method of analytic hierarchy process.The data of each evaluation index have been collected by means of the software of Arc GIS 9.3.Then the comprehensive qualities of farmland have been sorted according to the fuzzy optimization model.At last the spatial analyses function and digital mapping function have been applied and the permanent basic farmlands designated.The example suggests that the evaluation results are more scientific and reasonable by determining the weight of related evaluation indexes by means of analytic hierarchy process.The fuzzy optimization model is able to solute the problem that quantifies difficultly.GIS technology is powerful in data acquisition,basic farmland location and mapping exportation.Besides,this research also provides scientific evidence for the designation of basic farmland based on village or town scale.