Effect of expansion of lotus vegetation on methane food web in a shallow lake

2015 Fiscal Year Final Research Report

• Project/Area Number: 25440232
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Ecology/Environment
• Research Institution: Tohoku University
• Principal Investigator: SHIKANO SHUICHI 東北大学, 東北アジア研究センター, 准教授 (70154185)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 湖沼 / 安定同位体比 / メタン / ハス群落

Outline of Final Research Achievements

In Lake Izunuma, a shallow lake in Miyagi prefecture, the expansion of lotus vegetation caused oxygen-depleted lake water recently. In the lotus vegetation, methane diffused into lake water from the sediments and was accumulated in the lower layers during summer period. From the bacterial community analysis using the environmental DNA, the methane oxidizing bacteria which could grow in lake water were detected, and the changes in bacterial community corresponded to methane concentration and water temperature. Since carbon stable isotope ratios of zooplankton and fishes were depleted during summer period, it is suggested that methane food web originated from biogenic methane and methane oxidizing bacteria may be expanding to lake water environments.

Free Research Field

生態学