http://www.cnr.it/ontology/cnr/individuo/prodotto/ID75171
Variability of the microbial biomass and activity in the Ross Sea (Antarctica) and its implication on eco system carbon cycle. (Contributo in atti di convegno)
- Type
- Label
- Variability of the microbial biomass and activity in the Ross Sea (Antarctica) and its implication on eco system carbon cycle. (Contributo in atti di convegno) (literal)
- Anno
- 2008-01-01T00:00:00+01:00 (literal)
- Alternative label
La Ferla R., F. Azzaro, M. Azzaro, G. Maimone and L.S. Monticelli (2008)
Variability of the microbial biomass and activity in the Ross Sea (Antarctica) and its implication on eco system carbon cycle.
in EGU Geophysical Research Abstracts, Vol. 10,, Vienna, 13-18 April 2008
(literal)
- Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#autori
- La Ferla R., F. Azzaro, M. Azzaro, G. Maimone and L.S. Monticelli (literal)
- Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#numeroVolume
- Rivista
- Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#affiliazioni
- CNR_IAMC Messina (literal)
- Titolo
- Variability of the microbial biomass and activity in the Ross Sea (Antarctica) and its implication on eco system carbon cycle. (literal)
- Abstract
- The microbial contribution to the ocean biogeochemistry assumes a key role for the
equilibrium of the ecosphere. Nevertheless, few knowledges exist on the interrelationships
between climate variability and marine microbial biocenoses, although the
physical component describes the habitat but the biological one describes the ecosystem
evolution. Comparing the model simulations with the observations made during
campaigns and research cruises becomes increasingly crucial for evaluating oceanic
models' performance.
Such demand results particularly urgent in the Antarctic Ocean that rules the Earth
climate, since it acts as \"cold sink\" and \"engine\" of the worldwide oceanic currents.
Here, an overview on the variability of microbial biomass and activities, obtained
in the Ross Sea in spring-summer periods, is reported. Coastal and pelagic areas,
marginal-ice-zones and/or pack-ice-zones as well as spring and summer periods were
investigated from 1990 to 2005.
The aims of the study are: 1) to merge the data set on microbial biomass and activities
obtained in the frame of several PRNA projects performed over different time and spatial
scales; 2) to define whether microbial patterns can be used as index of ecosystemic
trends in relations with seasonal and/or annual variability.
Bacterioplankton biomass (epifluorescent microscopy and imaging analysis), total microbial
biomass (fractionated ATP), hydrolithic activities (LAP, b-GLU and AP estimates),
bacterial production (3H-leucine uptake) and respiratory rates (ETS activity)
were studied.
The main results are:
o Marginal ice zones show higher respiratory levels than pack ice zones, reflecting
the variability of standing stock and phytoplankton productivity. The
metabolic ratios Primary Production to Respiration (PP/R) convey the ice free
zones as productive systems (PP/R >1) whereas the ice covered zones appear
heterotrophic systems. Extending on annual scale the above referred findings,
we may assume that microbes act as sink of CO2 in spring-summer or as source
of CO2 in autumn-winter, respectively.
o The microbial biomass shows an increasing trend over 11 years in coastal areas,
whereas scarce variability occurred in pelagic areas. Sporadic peaks seem to be
related with peculiar microscale conditions as algal blooms.
o A comparison between microbiological, biochemical and sedimentological data
shows that the organic matter is mainly recycled within the Ross Sea continental
shelf rather than exchanged with the ocean. (literal)
- Prodotto di
- Autore CNR
Incoming links:
- Prodotto
- Autore CNR di
- Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#rivistaDi