耦合耕地综合质量和空间连通性的基本农田划定研究

Basic Farmland Demarcation Coupling Comprehensive Quality and Spatial Connectivity of Cultivated Land

保护集中连片的优质耕地对于保障国家粮食安全具有重要意义。本文以江西省兴国县为例,从耕地的自然质量、立地条件、生态条件3个层面系统构建耕地综合质量评价指标体系;基于TOPSIS(Technique for order preference by similarity to an ideal solution)综合评价法对耕地综合质量进行评价,引入耕地连片度、耕地空间连通格局分析了耕地空间集聚特征,综合耕地质量及其连通特征划定永久基本农田。结果表明:从耕地综合质量来看,兴国县耕地质量由高到低划分为4个质量等级,面积分别为6 204.95、16 031.72、19 321.79、3 573.76 hm^(2),占总耕地面积的13.75%、35.52%、42.81%、7.92%。总体来看,兴国县中等质量耕地居多,占比为78.33%。从耕地连通性来看,兴国县耕地连片程度由高到低划分为5个等级,其中一级~五级连片耕地面积分别为24 731.44、6 199.73、3 131.54、7 397.71、3 671.80 hm^(2),分别占耕地总面积的54.80%、13.73%、6.94%、16.39%、8.14%,耕地存在不同程度破碎化。将耕地质量三等以上、连片程度四级以上耕地划入基本农田,面积为37 029.62 hm^(2),占耕地总面积的82.05%,与原有划定基本农田相比,实现了划定后永久基本农田“总体稳定、布局优化、质量有提升”的目标。

Protecting high-quality concentrated and contiguous farmland is crucial for ensuring national food security.Taking Xingguo County in Jiangxi Province as a case study,an index system for evaluating comprehensive farmland quality was systematically constructed based on natural quality,site conditions,and ecological conditions.Utilizing the technique for order preference by similarity to an ideal solution(TOPSIS)comprehensive evaluation method,farmland quality was assessed.Farmland spatial aggregation characteristics were analyzed through farmland contiguity and spatial connectivity patterns,leading to the demarcation of permanent basic farmland based on comprehensive quality and connectivity.Results indicated that Xingguo County's farmland quality was divided into 4 grades,with areas of 6204.95 hm^(2),16031.72 hm^(2),19321.79 hm^(2),and 3573.76 hm^(2),representing 13.75%,35.52%,42.81%,and 7.92%of the total farmland area respectively,with the majority falling in the medium quality range at 78.33%.In terms of farmland connectivity,the area was classified into 5 contiguity levels,with areas of 24731.44 hm^(2),6199.73 hm^(2),3131.54 hm^(2),7397.71 hm^(2),and 3671.80 hm^(2),accounting for 54.80%,13.73%,6.94%,16.39%,and 8.14%of total farmland area,revealing varying degrees of fragmentation.Farmland of grade three or above and contiguity level four or above was designated as permanent basic farmland,covering 37029.62 hm^(2),or 82.05%of the total area.This delineation achieved the goal of"overall stability,optimized layout,and improved quality"compared with previous permanent basic farmland designations.