山区耕地细碎化对农户耕地撂荒的影响

研究山区耕地细碎化对耕地撂荒的影响对保障山区粮食安全、促进山区耕地整治与可持续利用具有重要意义。该研究以贵州省剑河县白都村为例，基于无人机高分辨率影像数据和农户调查数据，在提取农户耕地地块空间信息数据的基础上，选取综合指标测度法对农户耕地地块细碎程度进行刻画，从地块和农户两个层面分别运用Logistic和Tobit模型分析耕地地块细碎化对农户耕地撂荒的影响，探析农户耕地细碎化程度与其撂荒规模之间的关系。结果表明：1）研究区耕地细碎化程度较高，耕地撂荒现象严重。农户平均地块面积为0.044 hm2，平均耕地撂荒占比为29.50%；2）从地块层面看，耕地地块细碎化会加剧耕地撂荒，其中地块耕作距离对农户耕地撂荒具有显著的正向作用，地块面积对农户耕地撂荒具有显著的负向作用，且地块面积对农户耕地撂荒的作用强度高于地块耕作距离；3）从农户层面看，农户耕地细碎化程度越高，耕地撂荒规模愈大，农户耕地细碎化指数每提升10%，其耕地撂荒比例增加4.22%。研究结果可为推动山区细碎耕地资源的可持续利用与管理提供借鉴。

Impacts of mountainous land fragmentation on cultivated land abandonment of farmers

Impact of mountainous cultivated land fragmentation on the cultivated land abandonment can provide the management guidelines for the food security, and the consolidation and sustainable utilization of cultivated land in the mountainous areas. Taking the Baidu village in Jianhe County, Guizhou Province, China as an example, this study aims to evaluate the impact of mountains land fragmentation on the cultivated land abandonment of farmer. Firstly, the high-resolution image of Unmanned Air Vehicle (UAV) was interpreted to extract the elements of homestead, cultivated land plot, and road in the study area. The interpreted elements were verified to obtain the spatial data of cultivated land plots. The ownership of homestead and the contractual management right of cultivated land plot were determined through a field survey of farm households. Secondly, a comprehensive index measurement was used to quantify the degree of cultivated land fragmentation using the spatial data of cultivated land plots of farmers. Finally, a binary Logistic regression model was established to analyze the effect of cultivated land plot fragmentation on the cultivated land abandonment in a micro scale perspective. A Tobit regression model was applied to explore the relationship between the degree of plot fragmentation of farmers'' contracted land and the scale of cultivated land abandonment. The results show that: 1) There was the high degree of cultivated land fragmentation, indicating the relatively serious abandonment of cultivated land. The small scale was found in the land management of farm households, but the large number of plots was operated. Meanwhile, the average and minimum plot area of farm households were 0.044 hm2, and only 0.018 hm2, respectively, indicating the high degree of land fragmentation for the farm households. In addition, the average area of cultivated land was 0.342 hm2 by the farm households, but the average abandoned area of cultivated land reached 0.117 hm2. One-third of cultivated land in the farm households was abandoned, indicating the more serious abandonment of cultivated land. 2) The fragmentation of cultivated land plots increased the probability of cultivated land abandonment. Once the cultivated land plots were far away from their homestead, the farmers more inclined to abandon the part of the plots. Particularly, the small plot of cultivated land was tended to abandon. In addition, the Wald value revealed that the farmers tended to be more influenced by the size of the cultivated land plot, when making decisions about land abandonment. 3) The degree of cultivated land fragmentation was the primary factor on the scale of cultivated land abandonment with the continuous migration of rural labor force to cities. The higher the degree of cultivated land fragmentation of farmers was, the larger the scale of cultivated land abandonment would be. Specifically, the proportion of cultivated land abandonment increased by 4.22%, when the cultivated land fragmentation index of farmers increased by 10%. The finding can provide the important theoretical and practical implications to promote the sustainable utilization and management of finely-broken cultivated land resources in mountainous areas.