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Seasonal changes in the Modulus of Elasticity of living branches of three coniferous species
Author(s) -
OnwonaAgyeman Siaw,
Morioka Noboru,
Kondo Minoru,
Kitagawa Katsuhiro
Publication year - 1995
Publication title -
ecological research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.628
H-Index - 68
eISSN - 1440-1703
pISSN - 0912-3814
DOI - 10.1007/bf02347942
Subject(s) - cryptomeria , chamaecyparis , japonica , cypress , seasonality , zoology , environmental science , atmospheric sciences , physical geography , botany , biology , geography , ecology , geology
The seasonal changes in the Modulus of Elasticity ( E ) of living branches of Cryptomeria japonica, Chamaecyparis obtusa and Larix leptolepis were investigated over a period of 1 year by means of a quick and non‐destructive method previously introduced by the authors. Two sample trees were used for each species and 12 branches were selected from each tree. Readings of the experiments began in summer 1992 and were successively conducted in autumn 1992, winter 1993, spring 1993 and finally in summer 1993. Our investigations revealed that mean E values increased in cold seasons and decreased in warm or hot seasons. Mean values of E estimated in summer (1993) were relatively close to those estimated in summer 1992 indicating that any changes that occurred were the direct result of the environmental factors prevailing in the intervening seasons. Extremely high mean E values were measured when the branches were in a frozen state in winter; 69.4%, 29.9% and 24.6% higher than the previous summer for branches of Cryptomeria japonica, Chamaecyparis obtusa and Larix leptolepis , respectively. This sharp increase over the initial E values measured in summer 1992 was quite likely due to the freezing effect of rime on the branches.