Risk zone mapping for the Italian locust (Calliptamus italicus) based on GIS-MCA

Locust infestations are among the most prevalent natural disasters worldwide, posing significant threats to human livelihoods, socio-economic systems, and the environment. Therefore, the identification and categorization of locust plague risk areas are crucial for effective locust management and risk-informed decision-making. In this study, 11 locust plague-inducing factors were selected as evaluation criteria, and a spatial mapping framework of risk zones for Italian locust (<i>Calliptamus italicus</i>) occurrence was developed by combining a geographic information system with two multi-criteria analysis techniques: Analytic Hierarchy Process (AHP) and Orded Weighted Average (OWA).The results show that (1) in the multilevel evaluation index system developed in this study, the standard weights of the growing period NDVI, incubation period precipitation , and overwintering period soil moisture ranked in the top three among all evaluation factors, with 0.2535, 0.1715, and 0.1006. (2) The highest-risk zones obtained by the AHP were mainly concentrated in the southern Yumin County, Toli County, and the northwestern Hoboksar Mongol Autonomous County. The highest risk zone obtained by the AHP-OWA (<i>&alpha;</i> =1) method was extended to the northern Yumin County, the southern Shawan and Wusu based on the results of the AHP method.(3) The AHP-OWA method reduces the influence of subjective factors of AHP and improves the accuracy of risk assessment through ordered weights, and the number of historical locust occurrence points within each risk zone increases with the increase of risk level. Through the AHP-OWA method, decision makers can dynamically adjust the risk coefficients according to the actual situation, providing sufficient decision support for locust management.