基于地形的耕地破碎度指数设计与应用

针对当前耕地破碎化评价方法不够全面、客观以及难以开展地块尺度评价等问题，在总结和归纳已有研究的基础上，本研究对耕地破碎化进行了重新定义。基于耕地的面积、形态、聚集性以及地形特征，设计了耕地破碎度指数(Cultivated land fragmentation index，CLFI)。最后，以安徽省宣城市宣州区为研究区，在地块和乡镇尺度上，利用CLFI开展耕地破碎化评价，并分别与遥感影像、基于景观指数的评价结果进行对比分析。结果表明:在地块尺度上，CLFI的评价结果与耕地实际的破碎化状况基本吻合，并能结合道路、水系等数据，分析区域耕地破碎的原因和整治潜力；在乡镇尺度上，6个景观指数与CLFI回归方程的调整R2为0.44，通过显著性检验，CLFI一定程度上综合了6个景观指数的特征。本研究提出的CLFI更全面、直观和准确地反映了区域耕地破碎化状况，可为面向现代农业的国土综合整治和高标准农田建设等项目提供支撑。

Design and application of cultivated land fragmentation index based on terrain

In view of the problems that the current evaluation methods for cultivated land fragmentation are not comprehensive and objective, and it is difficult to carry out plot scale evaluation. On the basis of summarizing the existing research, this study redefines cultivated land fragmentation. Based on the area, form, aggregation, topographic of the cultivated land, cultivated land fragmentation index(CLFI)is designed. Taking Xuanzhou District, Xuancheng City, Anhui Province as the study area, the CLFI is used to evaluate the fragmentation of cultivated land at the plot and township scale. The evaluation results are compared with remote sensing image and the evaluation results based on landscape metrics. The results show: At the plot scale, the evaluation results of CLFI are basically consistent with the actual fragmentation of cultivated land, and can combine the road, water system and other data to analyze the reasons for the fragmentation and the potential for improvement of regional cultivated land; At the township scale, the adjusted R2 of the regression equation between the landscape metrics and CLFI is 0. 44, through the significance test, CLFI has integrated the characteristics of the six landscape metrics to a certain extent. In conclusion, the CLFI proposed in this study reflects the fragmentation of regional cultivated land more comprehensively, intuitively and accurately, which can provide support for integrated land renovation and high-standard farmland construction for modern agriculture.