基于AHP-CRITIC-TOPSIS的撂荒耕地复耕适宜性评价

Evaluation of Suitability of Abandoned Cultivated Land for Recultivation Based on AHP-CRITIC-TOPSIS

摘要:

为探析撂荒耕地复耕适宜性，以提高耕地利用率，本文以吉林省梨树县为研究区，基于谷歌地球引擎平台和梨树县2022年Sentinel-2影像数据，通过计算光谱特征、植被特征、纹理特征、地形特征等共46个特征，运用随机森林算法构建最优特征集，最终筛选39个特征参与分类，得出撂荒耕地范围。采用AHP-CRITIC-TOPSIS模型，分别从自然、土壤、社会经济条件3个维度构建撂荒耕地复耕适宜性评价模型，并将适宜程度划分为高度适宜、中度适宜、勉强适宜和不适宜4个等级，从而提出撂荒耕地复耕可行性方案。研究结果表明，2022年梨树县土地利用类型分类结果精度较高，总体分类精度以及Kappa系数均在95%以上，表明分类结果与实际地类一致程度高，整体分类效果好。梨树县撂荒耕地中不适宜复耕的撂荒耕地面积为1673.73hm2，主要位于研究区东南部地区；高度适宜复耕撂荒耕地面积为1071.67hm2，主要位于研究区西北部海拔较低的平原地区。目前国家耕地保护政策的落实对农村耕地利用情况确有改善，但农村耕地抛荒、利用效率低等问题依旧突出，研究结果可为梨树县以及周边地区提高耕地质量、保证粮食安全提供科学依据。

Abstract:

In order to explore the suitability of abandoned cultivated land for recultivation and improve the utilization rate of cultivated land, taking Lishu County, Jilin Province as the study area, firstly based on the Google Earth Engine platform and the 2022 Sentinel-2 image data of Lishu County, a total of 46 features such as spectral features, vegetation features, texture features, and terrain features were calculated, and random forest algorithm was used to construct the optimal feature set, and finally 39 features were screened to participate in the classification, so as to obtain the scope of abandoned cultivated land. Then the AHP-CRITIC-TOPSIS model was used to construct an evaluation model of the suitability of abandoned cultivated land for recultivation from three dimensions: natural, soil and socio-economic conditions, and the suitability was divided into four grades: highly suitable, moderately suitable, barely suitable and unsuitable, so as to put forward a feasible scheme for the rehabilitation of abandoned cultivated land. The results showed that the accuracy of the classification results of land use types in Lishu County in 2022 was relatively accurate, and the overall classification accuracy and Kappa coefficient were above 95%, indicating that the classification results were consistent with the actual land types and the overall classification effect was good. The area of abandoned cultivated land not suitable for recultivation in Lishu County was 1673.73hm2, which was mainly located in the southeast of the study area, and the area of abandoned cultivated land suitable for recultivation was 1071.67hm2, which was mainly located in the low-altitude plain area in the northwest of the study area. At present, the implementation of the national cultivated land protection policy indeed improved the use of cultivated land in rural areas, but the problems of abandonment and low utilization efficiency of rural cultivated land were still prominent, and the results can provide a scientific basis for improving the quality of cultivated land and ensuring food security in Lishu County and surrounding areas.