Spatial and temporal variability of size-fractionated biomass and primary production in the Ross Sea (Antarctica) during austral spring and summer
Saggiomo, V.; Carrada, G.C.; Mangoni, O.; Ribera d'Alcalà, M.; Russo, A. (1998). Spatial and temporal variability of size-fractionated biomass and primary production in the Ross Sea (Antarctica) during austral spring and summer. J. Mar. Syst. 17(1-4): 115-127. https://dx.doi.org/10.1016/S0924-7963(98)00033-5
In: Journal of Marine Systems. Elsevier: Tokyo; Oxford; New York; Amsterdam. ISSN 0924-7963; e-ISSN 1879-1573, more
Also appears in:Le Fèvre, J.; Tréguer, P. (Ed.) (1998). Carbon Fluxes and Dynamic Processes in the Southern Ocean: Present and Past. Selected papers from the International JGOFS Symposium, Brest, France, 28-31 August 1995. Journal of Marine Systems, 17(1-4). Elsevier: Amsterdam. 1-619 pp., more
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| Keywords |
Aquatic communities > Plankton > Nannoplankton
Aquatic communities > Plankton > Phytoplankton
Behaviour > Feeding behaviour > Grazing
Biological production > Primary production
Control > Population control
Fauna > Aquatic organisms > Aquatic animals > Shellfish > Marine organisms > Marine crustaceans
Ice edge
Organic compounds > Carbohydrates > Glycosides > Pigments > Photosynthetic pigments > Chlorophylls
Population characteristics > Biomass
Population characteristics > Population structure > Size distribution
PS, Ross Sea [Marine Regions]
Marine/Coastal |
| Authors | | Top |
- Saggiomo, V., more
- Carrada, G.C.
- Mangoni, O.
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- Ribera d'Alcalà, M.
- Russo, A.
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| Abstract |
The results of a study on the spatial and temporal dynamics of size-fractionated biomass and production of phytoplankton in the Ross Sea during the austral spring and summer are reported. The spring cruise took place in the offshore Ross Sea from 14 November to 14 December 1994. Sampling was carried out on a transect of 27 stations distributed from 76.5 to 72.0°S along 175°E, and covered the three main Antarctic environments of the polynya open waters, the marginal ice zone and the pack ice area. Three subsystems were identified. The subsystem of the polynya was characterised by the predominance of the micro- and nano-planktonic fractions, chlorophyll (Chl a) concentrations from 69.6 to 164.7 mg m−2 and production rates from 0.68 to 1.14 g C m−2 day−1. The second subsystem, the marginal ice zone, showed a relative increase of the micro-planktonic fraction, high biomass levels (from 99.64 to 220 mg Chl m−2) and production rates from 0.99 to 2.7 g C m−2 day−1. The subsystem of the pack ice area had a phytoplankton community dominated by the pico-planktonic fraction and showed low biomasses (from 19.4 to 37.7 mg Chl m−2) and production rates (0.28 to 0.60 g C m−2 day−1). Selective grazing by krill is considered an important factor in determining the size structure of the phytoplankton communities. The summer study consisted of a time series carried out in inshore waters of Terra Nova Bay from 12 January to 8 February 1990. In a well stabilised water column and with high levels of PAR always available, the primary production rates of a community dominated by micro-plankton varied from 0.52 to 1.2 g C m−2 day−1 (average 0.84). A high P/B ratio, up to 3, and a remarkably elevated mean phaeopigment (Phaeo)/Chl a ratio of 2.4 indicated an active removal of biomass by grazing, confirmed by the presence of faecal pellets in quantities reaching 6000 m−3 in the upper 50 m. The peculiarities of the inshore versus offshore environments in terms of community size structure, production processes and their implications as regards the food web are discussed. |
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