| Abstract: | The direct fluorescent-antibody technique was employed to determine the distribution patterns of four species of methanogens in the sediments of Lake Erie and Cleveland Harbor. Methanobacterium ruminantium was the most numerous methanogen found in regions of high-organic-silt sediments. The population of this species ranged from 106 to 109 cells/g of dry sediment. Methanobacterium strain MoH and Methanosarcina barkeri were identified in sand-silt, clay, or sand sediments. These methanogens ranged in density from 106 to 107 cells/g of dry sediment. Methanospirillum hungatii was observed only after an organic enrichment was performed on Cleveland Harbor sediments. The seasonal and selective sediment distribution of these methanogens appears to be related to the type and concentration of carbon as substrate as well as to the activities of heterotrophic and sulfate-reducing bacteria. |
