Predicting global geographical distribution of Lolium rigidum (rigid ryegrass) under climate change

Abstract

SUMMARYLolium rigidum L. (rigid ryegrass) is one of the most extensive and harmful weeds in winter cereal crops. A bioclimatic model for this species was developed using CLIMEX. The model was validated with records from North America and Oceania and used to assess the global potential distribution of L. rigidum under the current climate and under two climate change scenarios. Both scenarios represent contrasting temporal patterns of economic development and carbon dioxide (CO2) emissions. The projections under current climatic conditions indicated that L. rigidum does not occupy the full extent of the climatically suitable area available to it. Under future climate scenarios, the suitable potential area increases by 3·79% in the low-emission CO2 scenario and by 5·06% under the most extreme scenario. The model's projection showed an increase in potentially suitable areas in North America, Europe, South America and Asia; while in Africa and Oceania it indicated regression. These results provide the necessary knowledge for identifying and highlighting the potential invasion risk areas and for establishing the grounds on which to base the planning and management measures required.