Chemical pproxy parametarization for evaluating prehistoric human activities.

点击翻译按钮获取中文摘要

The purpose of this project is to prepare analytical procedures to identify a chemical evidence of human activities and to develop a chemical method to discriminate human remains from natural substances found in archeological sites. We focused organic compounds and stable isotope compositions, as both parameters are expected to characterize human agricultural activity and domestication of wild animals.Soil samples were collected from some archaeological sites, modern agricultural fields and natural fields. Some compounds in lipid fraction were extracted for identifying molecular composition by gas chromatography-mass spectrometer analysis. Stable carbon and nitrogen isotopes ratios were simultaneously studied to characterize biogeochemical perturbation of soil organic matter under taking agricultural activity. Bone collagen isotope analyses were also applied to discriminate domestication of Sus scrofa from wild boar populations.Soil organic matter analysis in modern agricultural field … More revealed that δ^<13>C and δ^<15>N of soil organic matter can be a useful proxy indicating C4 plants cultivation and consequent human perturbation of the soil microbe. Based on this result, soil samples from Bibi excavation site, a middle-Jomon sites in Chitose city, Hokkaido, evidences that there should be some kind treatment by prehistoric human at least 4,000 years, ago. In addition to this evidence molecular evidence by deoxycholic acids, a component of human bile, for soild lipid fraction also suggested likely usage of human leftover as fertilizer or toilet.Same analysis was applied to soil samples from burial site, Kamifukushima Nakamachi in Gunma prefecture, a lost village by a volcanic eruption in Edo era. Deoxycholic acid was detected closely in the soil from both a farm and manure sink in a farmer house, indicating that such molecules can be a promising proxy indicating manure treatment.Carbon and nitrogen isotope ratios of bone collagen were used to identify a individual of pigs from wild boar. We revealed that early domestication of boar could produce pigs having unusual isotopic patterns due to artificial feeding by human being, then it ca be useful proxy to detect early evidence of pig feeding. Less