Bioclimatic limits and range shifts of cold-hardy evergreen broad-leaved species at their northern distributional limit in Europe

The few native evergreen broad-leaved species occurring in central Europe have attracted the interest of generations of scientists; thus, the factors limiting their northern distribution have been well studied. For investigation of climate change-driven range shifts, these climate-sensitive species are particularly well suited. We here analyse recent range shifts of some of the cold-hardiest evergreen broad-leaved species, including both native and introduced species in Europe. Based on updated field data and outputs from bioclimatic models, we show that the milder winter conditions of the last few decades are consistent with the northward expansion of potential ranges and an increase in the number of evergreen broad-leaved species. At the landscape scale, these species indicate a considerable change in the composition and structure of temperate deciduous forests in various parts of Europe.