绰墩遗址古、今水稻土的正构烷烃和正脂肪酸特征分析

Composition Features of n-Alkanes and Fatty Acids in Paddy Soil in Chuodun Archaeology Site and Hengjing Site, China

利用GC外标定量法在绰墩遗址古水稻土和现代水稻土中检测出微量的生物标志物,包括正构烷烃、正脂肪酸以及正脂肪醇等。结果表明,古水稻土表层和现代水稻土的正构烷烃来源于低等藻类生物和陆生高等植物。C27/C31比值显示土层中植被类型以草本植物为主。正脂肪酸来源于低等藻类生物。而古水稻层正构烷烃来源于低等藻类生物,可能是由于绰墩遗址曾受海侵影响,或者是由于受人类稻作活动影响,土壤火烧后长链烷烃转化为低链烷烃,低链烷烃(<C20)占绝对优势。

Using the external standard GC analysis, trace biomakers, including n-alkanes, fatty acids and n-alkanols, have been detected from paddy soil in Chuodun archaeological site and Hengjing site in Jiangsu Province. The results indicated that the n-alkanes have been extracted from the surface layer of these two paddy soils, derived from acteria and algae and higher plants. The ratio of C27 and C31 shows the layers were predominated by the herbaceous plants. The n-alkanes in the layer of Holocene paddy soil in Chuodun archaeological site originated from algae, which could be explained by （1） the transgression, or （2） human rice cropping activities using fire. Accumulation of the homologues of lower molecular weight （〈 C20） was dominant in the post-fire samples.