open access

https://hdl.handle.net/2115/47188

Seasonal Changes in Organic Matter Mineralization in a Sublittoral Sediment and Temperature-Driven Decoupling of Key Processes

英語

2010-10

Springer New York

Microbial Ecology

60(3)

551-560

Seasonal changes in the mineralization of organic compounds in sediments were investigated in temperate, sublittoral zone sediments (Tokyo Bay, Japan). The total mineralization rate and sulfate reduction rate showed large seasonal variations over the year, and although the fluctuations in both rates correlated with temperature, the latter was irregularly high in May. The concentration of organic carbon dissolved in interstitial water was specifically high in April. A culture-based experiment was also conducted under temperatures corresponding to the seasonal changes. In the culture incubated at a temperature corresponding to April (13℃), hydrolysis and fermentation proceeded, but terminal oxidation was hindered, thereby resulting in acetate accumulation. At a temperature corresponding to May (22℃), acetate oxidation coupled with sulfate reduction was observed. The temperature-related differences were also reflected in the bacterial community structure in the cultures analyzed by DGGE. In the culture incubated at the lower temperature, sulfate-reducing bacteria of incomplete oxidizers was detected, while sequence found in the culture incubated at the higher temperature was related to complete oxidizers. These results suggest that complete and incomplete oxidizing sulfate-reducing bacteria act as distinct functional groups, responding to temperature in different ways, particularly in environments characterized by large temperature fluctuations.

学術雑誌論文

Accepted Manuscript

The original publication is available at www.springerlink.com

0095-3628