The sensitivity and response of the threatened endemic shrub Arbutus pavarii to current and future climate change.

Abstract

Climate change is expected to significantly alter and modify the ecological conditions of plant distribution and growth, particularly in the Mediterranean Basin, which is considered one of the hot spots for global warming. Measuring and modeling the response (sensitivity) of wild plants to current and future climate is critical to predicting future biodiversity and ecological values. Arbutus pavarii Pamp. (family Ericaceae) is a narrow endemic Libyan medicinal plant and one of the Red List species according to the IUCN that faces the threats of extinction due to habitat deterioration, overuse, and low reproductive rates. In this study, the species distribution model (SDM) approach was used to model and forecast range shifts in Arbutus pavarii under current and future climate change scenarios at various Shared Socio-economic Pathways SSP1-2.6 (lowest emission scenario) and SSP5-8.5 (highest emission scenario) for the years 2050s and 2070s. The modeling results indicate that the current highly suitable areas of the plant will decrease in the future compared to the low and moderate ones. The distribution range of A. pavarii will increase under lower emission scenarios (SSP1-2.6, 2050s) by 1.12% but under higher emission scenarios (SSP5-8.5, 2070s), the suitability of the habitat will decrease by 1.39%. Given the low reproductive fitness and the anticipated rise in air temperature, A. pavarii is likely to encounter greater challenges in its natural existence and dispersal. Lands with high elevation and precipitation are suitable for its future distribution. We recommend further ecophysiological and tree-ring studies on this species to investigate its growth-climate relationship and performance under drought conditions. The in-situ conservation of A. pavarii as well as its cultivation in the projected high and moderate habitats are recommended. Local community engagement may be beneficial in any conservation program for this species.