丘陵山区耕地"林果化"与复耕潜力评价

Evaluation of Conversion of Cultivated Land to Forest or Orchards and Associated Reclamation Potential in Hilly and Mountainous Areas

摘要:

"林果化"耕地复耕是落实国家耕地"大占补"战略、保障粮食安全的关键举措。本研究以江西省瑞金市为例，通过构建"地形梯度-耕地质量"耦合模型，集成地形综合指数（TCI）与CRITIC-TOPSIS方法，系统评价"林果化"耕地复耕潜力并制定分区优化策略。结果表明：2009---2023年，瑞金市耕地"林果化"总面积达6 495.67 hm2，占耕地总面积19.81%，其中转为果园3 984.75 hm2（占12.15%）、林地2 510.92 hm2（占7.66%），空间分布呈"中部集聚、南高北低"特征。地形梯度分区显示，"林果化"耕地集中于河谷平原区与低山丘陵区，"林果化"面积分别为3 250.39、2 645.47 hm2，占比分别为50.04%、40.73%，中山陡坡区面积17.37 hm2，占0.26%。耕地质量评价结果表明，Ⅰ~Ⅲ等优质"林果化"耕地面积5 210.61 hm2，占"林果化"耕地总面积的80.22%，凸显耕地资源流失对粮食安全的严峻威胁。基于GIS空间叠加与恢复潜力矩阵，划分优先复耕区（5 220.41 hm2，80.37%）、有条件复耕区（448.50 hm2，6.90%）及限制复耕区（826.76 hm2，12.73%），提出"平原机械化复耕-丘陵梯田化改造-陡坡生态保育"的分级治理方案。研究成果可为南方丘陵山区破解"耕-林-果"空间冲突、落实"藏粮于地"战略提供科学范式，对保障耕地产能具有重要实践价值。

Abstract:

Reclaiming cultivated land that has been converted to forest or orchard is a key measure for implementing the national "large-scale requisition-compensation" strategy and ensuring food security. Taking Ruijin City, Jiangxi Province as a case study, a "terrain gradient-cultivated land quality" coupling model was constructed, the terrain comprehensive index (TCI) was integrated with the CRITIC-TOPSIS method, and the reclamation potential of cultivated land converted to forest or orchard was systematically evaluated, thereby formulating a zoning optimization strategy. The results showed that from 2009 to 2023, the total area of cultivated land converted to forest or orchard in Ruijin City reached 6,495.67 hm2, accounting for 19.81% of the total cultivated land. Among this, 3,984.75 hm2 (12.15%) were converted to orchard and 2,510.92 hm2 (7.66%) to forest, with a spatial distribution characterized by "central agglomeration and a south-high, north-low" pattern. The terrain gradient zoning showed that the converted land was concentrated in the valley plain and low hilly areas, with areas of 3,250.39 hm2 (50.04%) and 2,645.47 hm2 (40.73%), respectively. The area in the medium-mountain steep slope zone was only 17.37 hm2 (0.26%). The cultivated land quality evaluation results showed that the area of high-quality (grades Ⅰ~Ⅲ) cultivated land converted to forest or orchard was 5,210.61 hm2, accounting for 80.22% of the total converted area, highlighting the serious threat that the loss of cultivated land resources posed to food security. Based on GIS spatial overlay and a restoration potential matrix, the converted land was classified into priority reclamation areas (5,220.41 hm2, 80.37%), conditional reclamation areas (448.50 hm2, 6.90%), and restricted reclamation areas (826.76 hm2,12.73%). A hierarchical management strategy was proposed: mechanized reclamation in plains, terracing in hilly areas, and ecological conservation on steep slopes. These findings can provide a scientific paradigm for resolving the cropland-forest-orchard spatial conflict and implementing the storing grain in the land strategy in the hilly and mountainous areas of southern China, offering important practical value for safeguarding cultivated land productivity.