Mass elevation effect and continentality have a stronger impact on global treelines than spatial isolation

Aim The global relationship between treeline elevation and temperature (or latitude as a proxy) is well established. However, additional large-scale regional abiotic influences such mass effect (MEE), continentality isolation are superimposed onto the latitude-treeline relationship. To quantify these effects, we apply globally applicable measures test effects of MEE, an aspect continental climate on elevation. Location Global elevations (n = 629). Methods We sampled sites using earth observation. calculated MEE distance to nearest mountain chain limits. Continentality was assessed by coastline. Isolation another within comparable elevational band. Results latitudinal pattern showed distinct bimodal Treeline increased substantially with coastlines while even decreased elevations. Main Conclusions Our study shows consistent coastline elevation, contributing our basic understanding biogeographic processes governing formation. reduce cloudiness increase solar radiation, resulting in higher not may be influenced immigration speciation. Understanding formation comprehensive contributes better how environmental conditions determine vegetation boundaries at large spatial scales.