Optimizing soil management by identifying and prioritizing the factors affecting soil erosion in Fars province with grey multiple-criteria decision-making approach

Soil erosion is one of the main phenomena related to soil degradation that threatens environmental sustainability and soil productivity. It has always been a major environmental challenge worldwide. Soil erosion and its harmful consequences are a serious obstacle to the development and progress of countries and have adverse effects on agricultural production, water quality, and ecosystem health. Soil erosion control intends to promote innovative land management approaches. Soil conservation methods reduce soil erosion, improve soil structure and water uptake, and maintain soil moisture. Therefore, it is necessary to study soil erosion factors and provide management strategies to mitigate it. This study identifies and prioritizes soil erosion factors and strategies to prevent soil erosion in Fars, Iran.

This research is applied in terms of purpose, with a descriptive-survey nature. This study presents a combined approach based on Grey SWARA and Grey ARAS methods to identify soil erosion factors and prioritize methods to prevent soil erosion. After literature review and interviewing an expert panel, the soil erosion factors in Fars were identified and classified into technical, chemical, social, environmental, and climatic. The weight of the criteria was calculated by the Grey SWARA method. Then, the suggested methods and strategies were identified and provided to the panel to evaluate based on the criteria by completing a questionnaire. Then, they were finally prioritized using the Grey ARAS approach. In order to consider the uncertainty and indeterminacy of opinions, grey numbers were used in the calculations.

The results indicated the following as the most important factors affecting soil erosion, respectively: "soil erodibility," "low aggregate stability," "deforestation and ecosystem degradation," "cultivation on slopes and plowing of sloping lands," "loss of vegetation," and "reduced organic matter." The most important preventative measures were prioritized as follows: "ratifying and implementing regulations to preserve soil and natural resources and the developing training and promoting workshops, promoting conservation tillage and smart agriculture, adding organic matter to the soil, mulching the soil with organic or artificial material, and adopting bioengineering methods, such as soil stabilizing bacteria" and "rangeland enclosure and fencing and promotion of industrial livestock.

As unfortunately, in Iran, soil erosion is several times the global average, and a large volume of good soil becomes out of reach per year, it requires serious management measures. More specifically, an extensive management plan should address soil erosion in Fars. It can be expected that findings in this research will help water, soil, and agriculture decision-makers make the most appropriate decisions and solutions to solve soil erosion problems.