The Phytogeography of Northern Europe

Abstract

Eilif Dahl, who died in 1993, had one of the most original and creative minds in plant geography. His approach went far beyond the description of distribution patterns and the establishment of correlations between distributions and particular climatic variables. His understanding of physiological mechanisms that influenced and controlled the observed distributional patterns was a key feature of his numerous ideas and hypotheses. He was also aware of the importance of history as an influence on present-day plant distribution, especially in arctic plants. In The Phytogeography of Northern Europe Dahl brings to bear his wide range of interests in physics, chemistry, geology, climatology, meteorology and mathematics, as well as plant ecology and plant systematics, to analyse and explain the distribution of individual plant taxa across north-western Europe. This book will stand as a testament to the ideas and inspiration of a fine scientist.

Postglacial history of vegetation, human activity and lake-level changes at Jezioro Linówek in northeast Poland, based on multi-proxy data

“…Increased precipitation encourages spruce growth (Koprowski 2013). Picea usually grows on damp soils (Giesecke and Bennett 2004) and it needs cold, snowy winters with average temperatures less than -6°C for its reproduction (Dahl 1998). It is known for occurring in areas with a more continental climate.…”

Spatio-temporal patterns in Lateglacial and Holocene vegetation and climate of Finnmark, northernmost Europe

“…Four variables were reconstructed. Three are bioclimatic variables related to physiological mechanisms by which plant species' distributions are limited (Dahl, 1998), and hence determine vegetation structure and composition: coldest month mean temperature (MTCO, °C); annual temperature sum above 5°C (GDD5, °C days); and annual ratio of actual to potential evapotranspiration (AET/PET -Priestley-Taylor α). The fourth, warmest month mean temperature (MTWA, °C), although less likely to have a mechanistic role in determining either species' distributions in the Arctic or sub-Arctic, or vegetation structure and composition in these regions, was included to provide a basis for comparison with studies reporting mean July temperature reconstructions.…”

A Richer, Greener and Smaller Alpine World: Review and Projection of Warming-Induced Plant Cover Change in the Swedish Scandes

“…Many alpine species are extremely tolerant of high temperatures per se (Dahl 1998;Birks 2008) as indicated, e.g. by their prospering and spread along roadsides far below the treeline, where emerging trees and shrubs are regularly mechanically exterminated (Kullman 2006;Westerström 2008;; http://www.kullmantreeline.com).…”

“…by their prospering and spread along roadsides far below the treeline, where emerging trees and shrubs are regularly mechanically exterminated (Kullman 2006;Westerström 2008;; http://www.kullmantreeline.com). Given that analogous disturbances by wind, water, slope and cryogenic processes continue to prevent full closure of tree-and ground-cover layers at high elevations (Kullman and Ö berg 2009), it is possible that growth and reproduction will become stimulated for some of those alpine species, which tolerate modestly warm conditions (Dahl 1998;Milbau et al 2009). In fact, observational data from the Alps indicate growing population sizes of certain highmountain species (Pauli et al 2001).…”