Human influences on formation and change in a Japanese cedar forest in the Akita region

2015 Fiscal Year Final Research Report

• Project/Area Number: 25450229
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Forest science
• Research Institution: Forestry and Forest Products Research Institute
• Principal Investigator: Shichi Koji 国立研究開発法人 森林総合研究所, 立地環境研究領域, 主任研究員 (10353715)
• Co-Investigator(Kenkyū-buntansha): IKEDA Shigeto 国立研究開発法人森林総合研究所, 立地環境研究領域, チーム長 (60353570) ; OKAMOTO Toru 国立研究開発法人森林総合研究所, 関西支所, チーム長 (40353627)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 秋田スギ / 人間活動 / 森林管理 / 歴史史料 / 完新世 / 植生変遷 / 花粉分析

Outline of Final Research Achievements

We reconstructed changes in the Cryptomeria japonica forest during the Holocene through pollen analysis of peat sediments collected from Akita Prefecture. Ancient documents recording past landscape use and human activity near the sampling sites were compared to reconstruct vegetation change. C. japonica was present to some degree at the beginning of the Holocene. The expansion of C. japonica occurred after 3000 cal BP at most sites. We consider that some small C. japonica groups, scattered near the sites, expanded with increasingly humid conditions. A recent decrease in C. japonica began ca. 500 cal BP of the Muromachi Period at most sites. It was associated with increases in diploxylon pines and herbaceous taxa. Moreover, results showed that Fagopyrum was cultivated at some sites. From comparison with historical documents and vegetation change, human influences, such as agriculture and timber utilization, began to increase in the end of the Muromachi Period around the Akita region.

Free Research Field

古生態学