基于灰色系统理论的挠力河流域净耕地面积预测

目的] 研究如何精准提取净耕地利用信息，为农田管理与耕地科学利用提供理论支持。方法] 基于灰色系统理论提出净耕地预测思路，以典型粮食产区挠力河流域为研究区，在土地利用变更调查数据支持下，运用净耕地系数、突变检测模型、灰色动态模型（GM）等数理模型，提取并验证净耕地（包括旱地和水田）利用信息。结果] 挠力河流域土地利用斑块面积变化表现出显著的“灰色”特征，对20 hm²等额面积区间的非旱地和非水田斑块面积累加处理，可增强数据列的规律性特征；GM （1，1）灰色系统模型和多项式预测方法均可较为准确地提取非旱地和非水田面积信息。2018年，挠力河流域旱地和水田的净面积分别是1.06×10⁶ hm²和3.87×10⁵ hm²，对应的净系数为97.65%和98.07%。结论] 耕地斑块面积变化具有灰色特征，可采用灰色系统理论进行净耕地面积预测。

Calculation on Effective Area of Cultivated Land in Naoli River Basin Based on Grey System Theory

Objective] The cultivated land use information was accurately extracted in order to provide theoretical support for farmland management and scientific use of cultivated lands. Methods] Effective area of arable land in the Naoli River basin was determined using grey system theory and associated theoretical assumptions, mathematical models, mutation detection model, and empirical analysis. Data used in the study came from land use change survey data and the net cultivated land coefficient. Results] Land use area showed significant grey characteristics. If accumulative treatments were applied to the area of the arable map within a certain area, the linear differential fitting equation could be used to predict the effective area of arable land in Naoli River basin. The grey system theory hypothesis could be applied for the accurate extraction of dryland and paddy fields. In 2018, the effective area of dryland and paddy fields was 1.06×10⁶ hm² and 3.87×10⁵ hm² in the Naoli River basin. The effective dryland coefficient and the paddy field coefficient were 97.65% and 98.07%, respectively. At the same time, the spatial distribution of effective arable land showed that more attention should be given to their actual utilization and development status in the downstream area of the outer Qixing River in the Naoli River basin, and in the northern part of Youyi County and the western part of Baoqing County. Conclusion] Grey system theory was proposed for determining changes in effective area of arable land. Gray system theory was found to be feasible for extracting effective cultivated land and its coefficient.