Spatiotemporal dynamics of grasshopper habitats under future climate projections, vegetation growth, and land use change

Abstract

Grasshopper outbreaks pose a persistent threat to grassland ecosystems and livestock production, yet large-scale monitoring of their suitable habitats under future climate change remains challenging due to complex interactions among climate, vegetation, and land use. Consequently, this study, taking China’s grasslands as the research area, explores the relationships between grasshoppers, host plants, and the environment and constructs habitat monitoring indicators using future climate, land use, and topographic data. Building on this, an ensemble model comprising Random Forest, eXtreme Gradient Boosting, and Light Gradient Boosting Machine is established to monitor the grasshopper suitable habitats under four Shared Socioeconomic Pathways (SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5) from 2021 to 2100. Results indicate that elevation, temperature seasonality, slope, and precipitation during the nymph and egg stages significantly influence grasshopper occurrence. Moreover, elevation, temperature seasonality, precipitation seasonality, slope, precipitation during the growth period, and isothermality are major contributors to host plant distribution. Suitable habitats are projected to remain concentrated in Inner Mongolia, northern Shaanxi, southern Gansu, Qinghai, and northern Xinjiang, with pronounced regional shifts over time. Low emission scenarios (SSP1-2.6) consistently possess the smallest and declining extent of most suitable habitats, whereas high emission pathways have the largest habitat, potentially creating environmental conditions that are more favorable for grasshopper persistence and expansion. The results provide spatially explicit insights for early warning, targeted monitoring, and sustainable grassland pest management in a warming world.