Open AccessDendroclimatic studies on conifers from central Europe and Great Britain
Author(s) -
SCHWEINGRUBER FRITZ H.,
BRÄKER OTTO U.,
SCHÄR ERNST
Publication year - 1979
Publication title -
boreas
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.95
H-Index - 74
eISSN - 1502-3885
pISSN - 0300-9483
DOI - 10.1111/j.1502-3885.1979.tb00438.x
Subject(s) - temperate climate , dendrochronology , latitude , precipitation , dendroclimatology , physical geography , period (music) , maximum density , montane ecology , climatology , geology , geography , ecology , meteorology , paleontology , biology , physics , geodesy , quantum mechanics , acoustics
Schweingruber, Fritz H., BrÄker, Otto U. & SchÄr, Ernst 1979 1201: Dendroclimatic studies on conifers from central Europe and Great Britain. Boreas , Vol. 8, pp. 427–452. Oslo. ISSN 0300–9483. The use of X‐ray densitometry for measuring tree rings makes it possible to consider the relations between climate and tree rings in a new light. Investigations so far have shown that it is the maximum density of the annual rings that provides the most important and best climatological information. Comparisons between density sequences are possible when the tree‐ring samples come from ecologically similar sites. Site characteristics are expressed by six different tree‐ring parameters. Relations between the maximum densities of various species from different regions are revealed by calculating the percentage of agreement. The growth rate of cell walls in latewood of all coniferous species from cool humid regions is limited mainly by summer temperatures. In Scotland, where the climate is cool‐oceanic and relatively stable, the cell walls grow from June to October. In the subalpine zone of the Alps and the Rocky Mountains near the timber line growth takes place mainly in August and September. Maximum density in trees of temperate sites is also primarily influenced by the summer temperature. Minimum density shows the relationship to the xerothermic site characteristics. On dry sites cambial activity and cell wall growth in latewood are mainly limited by precipitation during the growth period. Samples from the subalpine zones (1500–2200 m above sea level) between latitudes 45d̀ and 50d̀ North, i.e. those from the Western Carpathians, the Alps, and the Northern Appalachian Mountains, seem to form a unity. Samples from the oceanic region (20–600 m above sea level) between 52d̀ and 58d̀N latitudes show a different and incoherent picture. Only the present low level density during 1950–1975 is evident at all sites investigated for the last 200 years. By cross‐dating the annual tree‐ring sequences of living trees with samples of timber taken from ancient houses a 700‐year‐long chronology has been developed for the Northern Prealps in Switzerland. This chronology shows the approximate annual and decennial temperature changes; the sensitivity curve shows the different climatic variability in temperature.