Search this article
^<14>C dating of the organic substance in mineral particles was performed. The particles were collected from the soil microaggregates distributed over the river-beach of Hirosegawa in Sendai, Japan. The particles are inhabited by 10^5 (direct count), or 10-10^3 (plate count) cells of diverse microorganisms. The microorganisms have been thought to survive in the particles without remarkable growth or activity, and occasionally they are ejected from the particles and some strains of them begin to growth if the condition outside the particles is suitable for the organisms. The particles seem to become partial closed system, and the carbon exchange seems rarely occur. The age was determined as 17,100±60 BP. This age is remarkably old compared with other soil organics, of which ages are scarcely older than 10,000 BP. This result reveals that at least a portion of organics have been reserved for a long term in the particles, and supports the idea that the soil microorganisms can survive in the particles for a long term and that the particles can store diverse microorganisms.
タンデトロン加速器質量分析計業績報告 Summaries of Researches Using AMS 2001 (平成13)年度
名古屋大学加速器質量分析計業績報告書 13 228-235, 2002-03