首页>
外文期刊>ecological research
>Microdistribution of sulfate-reducing bacteria in sediments of a hypertrophic lake and their response to the addition of organic matter
【24h】
Microdistribution of sulfate-reducing bacteria in sediments of a hypertrophic lake and their response to the addition of organic matter
展开▼
机译：Microdistribution of sulfate-reducing bacteria in sediments of a hypertrophic lake and their response to the addition of organic matter
To clarify the ecological significance of the association of sulfate-reducing bacteria (SRB) with sediment particle size, SRB utilizing lactate (l-SRB), propionate (p-SRB) and acetate (a-SRB) were examined with different sizes of sediment particles in a hypertrophic freshwater lake using the anaerobic plate count method. The numbers ofl-SRB anda-SRB were 104–105colony forming units (CFU) per ml in the 0–3 cm layer and 102–103CFU ml−1in the 10–13 cm layer while the numbers ofp-SRB were one or two orders lower than those ofl-SRB anda-SRB. A sediment suspension was fractionated into four fractions (94 μm). The highest proportions ofl-SRB anda-SRB were found in the 10–94 μm fraction: 66–97 forl-SRB and 53–98 fora-SRB. The highest proportion ofp-SRB was found in the>94 μm fraction (70–74). These results indicate that most SRB were associated with sediment particles. One isolate from an acetate-utilizing enrichment culture was similar toDesulfotomaculum acetoxidans, a spore-forming sulfate-reducing bacterium. When lactate and sulfate were added to sediment samples,l-SRB anda-SRB in the<10 μm-fraction grew more rapidly than those in whole sediment for the first 2 days. This result suggests that nutrients uptake by free-living and small particle-associated (<10 μm) SRB is higher than that by SRB associ
展开▼
