The evaluation model for factors affecting soil quality in waste dumps open-pit coal waste dumps based on fuzzy mathematics

Abstract

Taking the Hequ open-pit coal mine waste dump as the research object, using the fuzzy analytic hierarchy process and expert scoring theory, 4 criteria and 25 factors were established, including the evaluation model of soil structure stability, soil water retention capacity, soil fertilizer retention capacity, soil biological activity, and factors affecting soil quality in the waste dumps. Using YAAHP calculation software, the weights of various influencing factors on the soil fertility restoration ability of the waste dumps were determined. Combining a fuzzy comprehensive evaluation method to determine soil nutrient standards, soil quality evaluation is divided into 5 levels, and the main influencing factors of soil restoration ability in open-pit coal mine waste disposal sites are quantitatively analyzed. The results showed that: The weight of soil fertility in the criterion layer of the evaluation model was the largest (0.548), followed by soil water retention capacity (0.198), soil biological activity (0.140), and soil structural stability (0.114). The weight of organic matter F1 in the factor layer was the highest (0.116). Due to the final evaluation score of the soil recovery ability of the target layer open-pit coal mine waste dumps is 53.584, the soil quality and nutrients of the waste dumps are in the middle level. The main factors of soil resilience are soil fertility and soil organic matter content, to provide management strategies for improving soil quality of dump, accelerating soil reconstruction, and promoting soil ecosystem restoration.