Quantitative evaluation of microbial food chain in wastewater treatment reactor

2017 Fiscal Year Final Research Report

• Project/Area Number: 16K14334
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Civil and environmental engineering
• Research Institution: National Institute for Environmental Studies
• Principal Investigator: Onodera Takashi 国立研究開発法人国立環境研究所, 地域環境研究センター, 主任研究員 (30583356)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Keywords: 生物学的排水処理 / 活性汚泥 / 食物網 / 下水処理 / 炭素・窒素安定同位体比

Outline of Final Research Achievements

Carbon and nitrogen stable isotope ratios (δ13C and δ15N) were determined in activated sludge, which was exposed to endogenous conditions for 36 days and contained a wide diversity of organisms across several trophic levels. The aim of this study was to elucidate the fluctuation of δ13C and δ15N through trophic transfer in the microbial consortia. The results show that the activated sludge became more enriched with 15N as degradation proceeded. Eventually, the sludge concentrations in the activated sludge decreased from 1610 to 710 mg/L and the δ15N of the sludge increased from 8.3‰ to 10.8‰. In contrast, the δ13C values of the sludge were stable. These findings provide new insights into understanding trophic transfer during microbial community succession and the effects of the feeding process on sludge degradation.

Free Research Field

環境工学