集成"适宜性-集聚性-稳定性"的永久基本农田储备区划定

永久基本农田储备区是永久基本农田的直接补划来源，划定并建设永久基本农田储备区对于稳定永久基本农田保护区格局，保障国家粮食安全具有重要意义。该研究从适宜性、集聚性、稳定性三个维度构建永久基本农田储备区评价体系，在一般耕地区开展综合质量评价基础上划定永久基本农田储备区；进一步结合三维魔方空间分类方法，制定了永久基本农田储备区的整治分区方案，并以江苏省常州市金坛区开展了方法实证。结果表明：1）从约束准则和评价准则两方面构建永久基本农田储备区划定准则，有利于提高永久基本农田储备区筛选的科学性和合理性；2）研究区基于耕地适宜性、集聚性、稳定性指标综合评价，在研究区划定了永久基本农田储备区7 307.8 hm2；3）结合耕地综合质量和空间分类方法可将永久基本农田储备区划分为综合利用潜力区、生产改善潜力区、发展提升潜力区、生产改善-发展提升潜力区等4种类型，针对不同类型区实施相应的整治措施，可进一步提升永久基本农田储备区的质量，为后续永久基本农田补划提供了坚实的基础。

Delimitating permanent prime farmland reserve areas on the perspective of suitability-cluster-stability

Abstract: Permanent prime farmland reserve areas have served as the direct supplementary sources of capital cultivated land. This type of high-quality cultivated land can widely be expected to extend for the ecological protection, and the sustainable "balance of occupation and supplement". Meanwhile, the reserve resources of cultivated land have been posed a great challenge on the occupation of new construction land, particularly with the recent acceleration of industrialization and urbanization. Therefore, it is very necessary to launch the spatial zoning of permanent prime farmland reserve areas, further to ensure national food security, quantity and quality stability of an optimal land pattern under an ecological protection for the high-quality cultivated lands. In this study, an evaluation system of permanent prime farmland reserve area was established from three dimensions of suitability, cluster and stability. Taking 2030 as the target year, a risk index of cultivated land conversion was also introduced to maximize the land use benefits. The policy requirements were firstly sorted to clarify the connotation of permanent prime farmland reserve areas. A FLUS model was then selected to estimate the land use structure under the multiple objectives of food security, economic development, and ecological protection. A conversion probability of cultivated land was also combined to predict the possibility of conversion of cultivated land to other land types, in order to achieve the stability of permanent prime farmland reserve areas during the conversion of cultivated land. A weighted superposition was conducted to evaluate the comprehensive quality of general cultivated land, where the permanent prime farmland reserve areas were classified, according to the evaluation. A three-dimensional Rubik''s cube spatial classification was also selected to divide into some consolidation zones. As such, the Jintan District of Changzhou City of Jiangsu Province was taken as a case study. The results showed as follows. 1) Two types of delimitation criteria (constraint and evaluation) were conducive to the rational decision-making on the permanent prime farmlands. 2) The comprehensive quality score of general cultivated land in the study area ranged from 35.52-100, with an average score of 67.76, which was generally at a relatively high level. A large number of cultivated lands with high comprehensive quality cannot be classified into the permanent prime farmland, where there was no protection. Therefore, it is highly urgent to protect the high-quality cultivated land by designating the permanent prime farmland reserve area. 3) A total of 7 307.8 hm2 permanent prime farmland reserve area was designated in the study area using the index evaluation of cultivated land suitability, cluster, and stability. 4) Four types of potential areas can also be divided into the comprehensive utilization, improving production, the development of ascension, and the spatial optimization, particularly with the comprehensive quality of cultivated land. Anyway, the finding can be beneficial to implement the regulatory measures for different types, further to improve the suitability, cluster and stability of permanent prime farmland.