Agricultural drought risk assessment considering risk transmission relationship: a novel fuzzy matrix synthesis with relative connection number

The quantitative assessment of regional agricultural drought risk is of great importance for the mitigation of regional droughts and the maintenance of food security. However, the complex structure of the drought risk system and the inherent uncertainty result in a lack of effective assessment methods. The study constructed a comprehensive assessment index system based on the six-element drought risk system. A novel Mutually Exclusive Relative Connection Number synthesizing the Fuzzy Risk Matrix (MERCN-FRM) method was proposed to assess agricultural drought risk. Additionally, a CRITIC method was improved through the integration of the set pair potential and entropy to weight the index. A case study was conducted on the Jianghuai watershed area located in the middle of east China with frequent drought disasters. The results demonstrate that the six-component drought risk framework offers a holistic view of how the risk factors interact. The enhanced CRITIC method can comprehensively represent the positive, negative, and uncertain fuzzy correlations of indicators microscopically. The MERCN-FRM methodology, through the utilization of MERCN, achieves a dynamic synthesis of the pessimistic and optimistic risk matrices. This approach not only surmounts the subjectivity and static nature inherent in traditional risk matrix synthesis methods, but also facilitates a more profound understanding of the interactive mechanisms within the subsystems of drought risk compared to other widely-used comprehensive evaluation methods. This approach could be employed as a novel tool for dynamically assessing regional disaster risk, aiding the decision-making for drought risk mitigation strategies.