title: Disparity in elevational shifts of European trees in response to recent climate warming.
abstract: Predicting climate-driven changes in plant distribution is crucial for biodiversity conservation and management under recent climate change. Climate warming is expected to induce movement of species upslope and towards higher latitudes. However, the mechanisms and physiological processes behind the altitudinal and latitudinal distribution range of a tree species are complex and depend on each tree species features and vary over ontogenetic stages. We investigated the altitudinal distribution differences between juvenile and adult individuals of seven major European tree species along elevational transects covering a wide latitudinal range from southern Spain (37°N) to northern Sweden (67°N). By comparing juvenile and adult distributions (shifts on the optimum position and the range limits) we assessed the response of species to present climate conditions in relation to previous conditions that prevailed when adults were established. Mean temperature increased by 0.86 °C on average at our sites during the last decade compared with previous 30-year period. Only one of the species studied, Abies alba, matched the expected predictions under the observed warming, with a maximum abundance of juveniles at higher altitudes than adults. Three species, Fagus sylvatica, Picea abies and Pinus sylvestris, showed an opposite pattern while for other three species, such as Quercus ilex, Acer pseudoplatanus and Q. petraea, we were no able to detect changes in distribution. These findings are in contrast with theoretical predictions and show that tree responses to climate change are complex and are obscured not only by other environmental factors but also by internal processes related to ontogeny and demography.
authors.affiliation: Departamento de Biogeografía y Cambio Global, Museo Nacional de Ciencias Naturales, Madrid, Spain. sonia.rabasa@mncn.csic.es
authors.forename: Sonia G
authors.initials: SG
authors.lastname: Rabasa
authors.forename: Elena
authors.initials: E
authors.lastname: Granda
authors.forename: Raquel
authors.initials: R
authors.lastname: Benavides
authors.forename: Georges
authors.initials: G
authors.lastname: Kunstler
authors.forename: Josep M
authors.initials: JM
authors.lastname: Espelta
authors.forename: Romá
authors.initials: R
authors.lastname: Ogaya
authors.forename: Josep
authors.initials: J
authors.lastname: Peñuelas
authors.forename: Michael
authors.initials: M
authors.lastname: Scherer-Lorenzen
authors.forename: Wojciech
authors.initials: W
authors.lastname: Gil
authors.forename: Wojciech
authors.initials: W
authors.lastname: Grodzki
authors.forename: Slawomir
authors.initials: S
authors.lastname: Ambrozy
authors.forename: Johan
authors.initials: J
authors.lastname: Bergh
authors.forename: José A
authors.initials: JA
authors.lastname: Hódar
authors.forename: Regino
authors.initials: R
authors.lastname: Zamora
authors.forename: Fernando
authors.initials: F
authors.lastname: Valladares
mesh_terms: D031002:Acer / Q000254:growth & development / Q000502:physiology; D000531:Altitude; D005060:Europe; D029962:Fagaceae / Q000254:growth & development / Q000502:physiology; D057232:Global Warming; D008954:Models, Biological; D028201:Pinaceae / Q000254:growth & development / Q000502:physiology; D063148:Plant Dispersal; D013045:Species Specificity; D013997:Time Factors; D014197:Trees / Q000254:growth & development / Q000502:physiology*
keywords: altitudinal gradient; climate change; forest; generalized additive models; species distribution