Abstract [Background] The essence of evaluating land reclamation suitability in mining areas is a type of classifying the land reclamation for the future according to certain evaluation rules (or criteria). Thus, it is feasible and reasonable to apply classification rules with decision tree induction method in suitability evaluation of land reclamation in mining areas. [Methods] In this paper, we applied the subordinate function method of the fuzzy mathematics to improve ID3 algorithm (the Iterative Dichotomiser 3) of the decision tree, established a model for evaluating land reclamation suitability, and then applied this improved model in Pingyu Second Mining Area. Selecting 7 evaluation indexes as the attributes of measurement, and extracting 100 units which directions of land reclamation have been determined as the samples, we established the decision tree for land reclamation suitability evaluation with the improved ID3 algorithm. Then, we applied the established classification rules of the decision tree to classify them according to their attributes, to evaluate various units and to determine the reclamation directions for various evaluated units. Further, to verify the accuracy of evaluation results, we compared the most frequently used limit condition method with the proposed method. [Results] The statistics result showed that there were 365.87 hm2 suitable for arable land, 98.83 hm2 suitable for woodland and 97.98 hm2 suitable for meadow by using improved decision tree model in the studied area. However, there were 334.95 hm2 suitable for arable land, 106.26 hm2 suitable for woodland and 121.47 hm2 suitable for meadow by using limit condition method in the studied area. The 92.50 % of evaluation results of the proposed method were consistent with those by limit condition method. In inconsistent results, the grades of evaluation result by limit condition method were lower than those by decision tree model. After comparing the two methods, the results revealed that the limiting condition method was more suitable for reclamation suitability evaluation of opencast coal mine damaged land, and the improved decision tree model proposed in this paper was more suitable for mine subsidence land of underground mining. Thus, from the above comparative analysis of two methods, combined with field research, the result based on improved decision tree model were more in line with actual study area, and the reclamation directions were also more reasonable. [Conclusions] The results indicated that this evaluation method for land reclamation suitability in mining areas based on the improved decision tree did not rely on the empirical knowledge but relied on classification rules/ criteria formulated by self-directed learning of the samples.The classification results obtained were more objective and reasonable. Furthermore, once the classification rules of decision tree have been determined, they can be directly applied in other areas to be evaluated in the same region and the classification process is simple, clear and easy to be operated.This approach can provide a new thinking way for the evaluation of land reclamation suitability in mining areas.
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