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, it’s natural and extended area covering around 1 million ha. Gradual environmental changes may allow species to track suitable habitats, whereas rapid changes can cause maladaptation, reduced fitness, and population decline. Using climatic variables, the potential current and future habitat suitability for European larch in Europe and Romania were modelled. The GBIF database was used to download the occurrences of the species. The objectives of this study were: to (i) Identify the climatic variables that influence the distribution of European larch; (ii) Predict potentially suitable areas for this species in Europe and Romania under current conditions; (iii) Predict potentially suitable areas for this species under three future periods (2041-2060, 2061-2080 and 2081-2100) and two distinct Shared Socioeconomic Pathways (SSPs) (245 and 585); (iv) Evaluate the range shifts. Mean Diurnal Range, Isothermality, and Precipitation of the Warmest Quarter were the climatic variables with the highest relative importance regarding the habitat suitability for European larch. In Europe, in all three periods and for both SSPs, the areas projected to be affected by a loss of habitat suitability (contraction) were around 10 times higher than those where conditions are predicted to improve (expansion). In Romania, for the 2081-2100 period and under the worst-case scenario, the very highly suitable area is projected to be around 3% of the country. The models should be further developed to integrate more important variables for assessing the habitat suitability of European larch.