Current and Future Habitat Suitability of Larix decidua in Europe and Romania

Abstract

European larch (Larix decidua) is one of the most important conifer species in Europe, with its natural and extended area covering around 1 million hectares. Gradual environmental changes may allow species to track suitable habitats, whereas rapid changes can cause maladaptation, reduced fitness, and population decline. Using climatic variables, we modelled the potential current and future habitat suitability for European larch in Europe and Romania, for three periods and two Shared Socioeconomic Pathways (SSPs) - SSP245 and SSP585. The GBIF database was used to download the occurrences of the species. Mean Diurnal Range (BIO2), Isothermality (BIO3), and Precipitation of the Warmest Quarter (BIO18) were the climatic variables with the highest relative importance regarding the habitat suitability for European larch. In Europe, the areas projected to be affected by a loss of habitat suitability (contraction) are between 24 and 44 times higher than those where conditions are predicted to improve (expansion). In Romania, for the 2081-2100 period and under the worst-case scenario (ssp585), the very highly suitable (excellent) area is projected to represent around 3% of the country. Modelling how climate change reshapes species distributions is essential for forest managers and policymakers who need robust mitigation and adaptation strategies. The models should be further developed to integrate more important variables for assessing the habitat suitability of European larch.