Risk assessment of transboundary locust habitat distribution and migration pathways under climate change: a case study of Kazakhstan and Xinjiang, China

Cross-border migration of Calliptamus italicus (C. italicus) and Locusta migratoria migratoria (L. migratoria migratoria) threatens agricultural security along the China-Kazakhstan border, yet their migration pathways remain poorly understood. This study integrates geospatial techniques (optimized Maximum Entropy (MaxEnt) and weighted overlay analysis) with multi-source habitat variables (climate, soil, vegetation) to map current and future habitat suitability and migration pathways. Future climate projections were generated using the BCC-CSM2-MR climate model. Key findings: (1) The MaxEnt model achieved robust performance (AUC > 0.93, TSS > 0.70), with precipitation seasonality, isothermality, and elevation as dominant drivers. (2) Projections indicate climate change will expand suitable habitats for the two locust species, moderate-high suitability areas in L. migratoria migratoria and low-moderate zones in C. italicus will progressively shrink under future climates. (3) Four and six potential migration pathways were identified for L. migratoria migratoria and C. italicus, concentrated along the Irtysh/Ili Rivers, Balkhash/Alakol Lakes, and Tianshan northern slopes. (4) Future scenarios predict corridor shortening and southward shifts, with SSP585 intensifying L. migratoria migratoria habitat fragmentation. Spatial overlap occurs in Irtysh River and Alakol Lake regions, highlighting cross-border monitoring priorities. These results provide geospatial evidence for optimizing early-warning systems and transboundary pest management strategies under climate change scenarios.