Microbial metabolic rates in the Ross Sea: the ABIOCLEAR Project
| Autor: | Ermanno Crisafi, Rosabruna La Ferla, Alessandro Ciro Rappazzo, F. Azzaro, L. S. Monticelli, Maurizio Azzaro, Federica Grilli, Theodore T. Packard, G. Maimone |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
0106 biological sciences
010504 meteorology & atmospheric sciences lcsh:QH1-199.5 010604 marine biology & hydrobiology heterotrophic energy production LTER lcsh:General. Including nature conservation geographical distribution 01 natural sciences Microbial respiration Ross Sea lcsh:QH540-549.5 Antarctica lcsh:Ecology 0105 earth and related environmental sciences Nature and Landscape Conservation heterotrophic production |
| Zdroj: | Nature Conservation, Vol 34, Iss, Pp 441-475 (2019) Nature Conservation 34: 441-475 |
| ISSN: | 1314-6947 1314-3301 |
| Popis: | The Ross Sea is one of the most productive areas of the Southern Ocean and includes several functionally different marine ecosystems. With the aim of identifying signs and patterns of microbial response to current climate change, seawater microbial populations were sampled at different depths, from surface to the bottom, at two Ross Sea mooring areas southeast of Victoria Land in Antarctica. This oceanographic experiment, the XX Italian Antarctic Expedition, 2004-05, was carried out in the framework of the ABIOCLEAR project as part of LTER-Italy. Here, microbial biogeochemical rates of respiration, carbon dioxide production, total community heterotrophic energy production, prokaryotic heterotrophic activity, production (by3H-leucine uptake) and prokaryotic biomass (by image analysis) were determined throughout the water column. As ancillary parameters, chlorophylla, adenosine-triphosphate concentrations, temperature and salinity were measured and reported. Microbial metabolism was highly variable amongst stations and depths. In epi- and mesopelagic zones, respiratory rates varied between 52.4–437.0 and 6.3–271.5 nanol O2l-1h-1; prokaryotic heterotrophic production varied between 0.46–29.5 and 0.3–6.11 nanog C l-1h-1; and prokaryotic biomass varied between 0.8–24.5 and 1.1–9.0 µg C l-1, respectively. The average heterotrophic energy production ranged between 570 and 103 mJ l-1h-1in upper and deeper layers, respectively. In the epipelagic layer, the Prokaryotic Carbon Demand and Prokaryotic Growth Efficiency averaged 9 times higher and 2 times lower, respectively, than in the mesopelagic one. The distribution of plankton metabolism and organic matter degradation was mainly related to the different hydrological and trophic conditions. In comparison with previous research, the Ross Sea results, here, evidenced a relatively impoverished oligotrophic microbial community, throughout the water column. |
| Databáze: | OpenAIRE |
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