A new method to analyze for ecoogical structure by measuring stable isotope ratios of microbial nucleic acids

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K17879
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 63010:Environmental dynamic analysis-related
• Research Institution: Research Institute for Humanity and Nature (2022-2023); Kyoto University (2021)
• Principal Investigator: Onishi Yuji 総合地球環境学研究所, 基盤研究部, 特任助教 (10847677)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 安定同位体 / 核酸 / 琵琶湖

Outline of Final Research Achievements

We investigated methods for recovery, purification, and isotope ratio measurements of microbial nucleic acids to establish a new method for accurately assessing the importance of microbial activity for nutrient resources supporting benthic animal communities in freshwater ecosystems. As a result, it became clear that the purification was problematic and that isotope ratios could not be successfully measured by the conventional methods. However, we established a new evaluation method for microbial activity using sulfur isotope ratios in freshwater ecosystems, and found that sulfur cycling in sediments and associated microbial activities are important as a nutrient resource for benthic animal communities.

Free Research Field

安定同位体生態学

Academic Significance and Societal Importance of the Research Achievements

淡水湖沼生態系において、堆積物中での硫黄酸化細菌や硫酸還元細菌の活動が、底生動物群集の栄養源として重要であることが初めて明らかとなった。これは、淡水湖沼生態系内にこれまで知られていない新たな栄養経路が存在していることを示唆している。この現象について、他の湖沼での調査を進めることによって、地球温暖化などの環境変動に対する淡水湖沼生態系の応答を理解する上で重要な知見が得られると期待される。