| Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2003: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 2002: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 2001: ¥1,900,000 (Direct Cost: ¥1,900,000)
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| Research Abstract |
I have taken a long core beyond 370,000 to 25,000 yr BP. from Kamiyoshi Basin near Kyoto City in western Japan. This core will provide a continuous vegetation history of the glacial-interglacial circles beyond 370,000 yr BP. The chronology was based on widespread tephra, AMS 14C dates. I have made clear the vegetation history since MIS 5e using pollen analysis. During MIS 5e (the last interglacial), evergreen oaks and Cryptomeria japonica were dominant in forests with Lagerstroemia whose modern habitat is districted in the South Eastern Island of Japan. In the period between MIS 5d and 5a, temperate conifer forests developed, composed of Cryptomeria japonica, Sciadopitys verticillata, and Cupressaceae trees associated mainly with cool-temperate deciduous broad-leaved trees. Pinaceous conifer vegetation dominated by Tsuga, Picea, and Pinus subgenus Haploxylon was dominant between 70 and 60 kyr BP, corresponding to isotope stage 4. Around 60 kyr BP, this was followed by cool-temperate deciduous broad-leaved forests composed mainly of Fagus crenata, Quercus subgenus Lepidobalanus and Ostrya/Carpinus. Temperate conifer forests dominated by Cupressaceae trees with Lepidobalanus (deciduous oaks) occurred in the interstade (MIS 3). From 30 kyr BP to 12 kyr BP (MIS 2), the conifer forests developed, composed of Abies, Tsuga, Picea and Pine with Betula trees. In 12 kyr BP, Fagus crenata became dominant in forests. Forests dominated by Fagus crenata in 12 kyr BP, changed to chestnut forests in the early Holocene, probably affected by fire disturbances. After the middle Holocene (after 6000 yr BP), Cryptomeria japonica, Cupressaceae trees, evergreen oaks and Fagus crenata became dominant in forests. Cryptomeria japonica was predominant in 2500 yrBP. Fires probably caused by human activities made the Cryptomeria forests decline. After that, the vegetation shifted to deciduouse and pine dominated forests.
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