Mats of colourless sulphur bacteria. 2. structure, composition of biota and successional patterns
Bernard, C.; Fenchel, T. (1995). Mats of colourless sulphur bacteria. 2. structure, composition of biota and successional patterns. Mar. Ecol. Prog. Ser. 128: 171-179
In: Marine Ecology Progress Series. Inter-Research: Oldendorf/Luhe. ISSN 0171-8630; e-ISSN 1616-1599, meer
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| Auteurs | | Top |
- Bernard, C.
- Fenchel, T., meer
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| Abstract |
Mats of colourless sulphur bacteria from a relatively exposed shallow water sediment and from a deeper, more protected sediment were studied. In the exposed habitat, patches of white sulphur bacteria had a limited lifetime and displayed a characteristic succession in which small sulphur bacteria (Thiospira, Macromonas) dominated at first followed by Thiovulum, which was eventually displaced by Beggiatoa; during summer phototrophic organisms dominated. Thiovulum films were only ~0.2 mm thick and the projected area of the cells covered only 7 to 36% of the sediment surface while mats of filamentous bacteria were thicker and represented a higher biomass. In the protected locality the Beggiatoa mats were ~0.6 mm thick and represented a 10-fold higher biovolume than those from the exposed habitat. The projected area of the filaments covered 2 to 3x the surface area of the sediment and had a combined length of 10 to 70 m cm-2. The mats had a porosity of 90 to 95% and did not contain a mucous matrix. Phototrophs (mainly filamentous cyanobacteria and diatoms) were always present. Protozoan biota included more than 80 species and represented a high cell density (corresponding to 104-105 ciliates ml-1 in addition to flagellates and lobose amoebae). Many species depended on sulphur bacteria for food. The mats sometimes also harboured several representatives of meio- and macrofauna. |
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