摘要:
划定基本农田保护区是保障国家粮食安全,提高粮食综合生产能力的重要举措.然而,2011年修订的《基本农田保护条例》只强调将优质耕地划入基本农田保护区,却没有对保护区形态做出明确要求,导致保护区片块数量多,边界线长且模糊不清,无形中增大了基本农田被占用的风险.基于此,本文拟采用逐级修正多因素综合评价法、基于Moran'sⅠ指数的局部空间自相关分析、GIS空间分析方法,以甘肃省榆中县2015年耕地为基础,对基本农田保护区进行优化.结果表明:①榆中县耕地质量总体是中等水平,其中高等地与中等地合计占79.76%.高质量耕地聚集区(HH)和低高集聚区(LH)可以划入基本农田保护区;②经过边界识别,共划定11个基本农田保护区,总面积75 878.17hm2,其中平原区3个,丘陵区5个,山地区3个.与优化前相比,能够完成土地利用总体规划确定的目标,图斑数量减少,单位图斑面积增大,边界线缩短且明确,景观格局优化.该研究过程和方法可为相关工作的开展提供参考.%Delimitation of basic farmland protection area is an important measure ensuring national crop security and improving comprehensive grain production capacity.However,the 2011 amendments to the "Regulations on the Protection of Basic Farmland" emphasized that high-quality farmland is only included in basic farmland protection areas.It did not make clear requirements for the protection region as well,which contributes to a large number of protected areas,long and obscure boundary lines,virtually increasing the risk of basic farmland being occupied.Therefore,taking country cultivated land in 2015 as an example,we adopted the method of step-by-step multi-factor comprehensive evaluation to optimize the basic farmland protection area based on farmland in Yuzhong County of 2015 and Moran's I index spatial autocorrelation analysis and GIS.We found that the quality of cultivated land in Yuzhong County is at a moderate level,with an overall amount of 79.76% for high-quality farmland and middle-leveled farmland.High-quality (HH) and low-quality (LH) agglomeration area can be allocated as basic farmland protection area.After boundary identification,11 designated basic farmland protection areas can be delimitated,with a total area of 75 878.17 hm2 including three plain areas,five hilly areas,and three mountainous areas.Compared with areas before optimization,we reached the goal of completing the overall land use planning to reduce the number of patches when patch unit area increases and the boundary line is shortened and cleared.The landscape pattern is optimized as well.Our research process and methodology provides a reference for the development of relevant work.