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Plants protect themselves against various stresses by using volatile terpenes, which are also key precursors of climate‐relevant constituents in the atmosphere. Conifers store terpenes in storage pools, which serve as emission sources. However, how leaf terpene contents influence the quantity and composition of emissions is uncertain. Here, we examined whether they explain the profile of terpene emissions by using the measurements of 6 monoterpenes and 2 diterpenes stored in and emitted from the same branches of 10 local populations in Japanese cedar (Cryptomeria japonica), a common conifer in Japan. We estimated partial pressures of terpenes from leaf terpene contents by using a thermodynamic algorithm. The estimates correlated well with emissions of monoterpenes, suggesting the release of monoterpenes from the storage pools. High tree‐to‐tree variations in emissions of individual terpenes did not correlate with variations in concentrations of corresponding terpenes in leaves. Diterpenes (ent‐kaurene and phyllocladene) were emitted in most cases when individual trees held corresponding diterpenes, suggesting a linkage between emissions and storage pools, but the emissions were not explained by the algorithm owing to their low vapor pressure. [ABSTRACT FROM AUTHOR]

Abstract: The essential oils from a bogwood trunk of sugi (Cryptomeria japonica D. Don) from Sanbe-cho, Shimane, Japan, preserved for c. 3500–3800 years in volcanic ash (S-bogwood), were analyzed using gas chromatography-mass spectrometry (GC/MS). Eight sesquiterpenes and four diterpenes were identified. The main components were simonellite (19.2%), cis-calamenene (11.6%), and α-phyllocladane (8.8%). These results were compared with previous results for oils from a fresh stump of C. japonica, from Muikaichi-cho, Shimane, Japan (fresh wood) and for oils from a stump of another sugi bogwood preserved for c. 3000 years in sediment of a muddy field in Abu-cho, Yamaguchi, Japan (Y-bogwood). Simonellite, α-phyllocladane, selinane (4.3%), and eudalene (2.7%) were identified for the first time in bogwood trunk oil. Ash generated by oxidation of each of the two bogwood samples and fresh wood sample at 700°C was analyzed using scanning electron microscopy with energy dispersive X-ray analysis (SEM/EDXA). The major elements were S and Ca in S-bogwood ash, Fe and Ca in Y-bogwood ash, and K and Ca in the fresh wood ash, respectively. Sulfur in the S-bogwood ash is thought to have come from volcanic ash. The results suggest that S-bogwood was influenced directly by volcanic ash and the degree of terpenoid alteration was more drastic than that of Y-bogwood. [Copyright &y& Elsevier]