Access the full text.
Sign up today, get DeepDyve free for 14 days.
J. Walsh (1971)
Relative Importance of Habitat Variables in Predicting the Distribution of Phytoplankton at the Ecotone of the Antarctic Upwelling EcosystemEcological Monographs, 41
W. Harrison (1980)
Nutrient Regeneration and Primary Production in the Sea
J. Strickland, T. Parsons (1968)
A practical handbook of seawater analysis
D. Hurd (1972)
Factors affecting solution rate of biogenic opal in seawaterEarth and Planetary Science Letters, 15
L. Solórzano, J. Strickland (1968)
POLYPHOSPHATE IN SEAWATE1Limnology and Oceanography, 13
L. Codispoti, G. Friederich, R. Iverson, D. Hood (1982)
Temporal changes in the inorganic carbon system of the southeastern Bering Sea during spring 1980Nature, 296
A. Kamatani (1969)
Regeneration of Inorganic Nutrients from Diatom DecompositionJournal of the Oceanographical Society of Japan, 25
B. Peterson (1980)
Aquatic Primary Productivity and the 14C-CO2 Method: A History of the Productivity ProblemAnnual Review of Ecology, Evolution, and Systematics, 11
Y. Saijo, T. Kawashima (1964)
Primary Production in the Antarctic OceanJournal of the Oceanographical Society of Japan, 19
G. Jacques (1978)
Campagne ANTIPROD I - Marion Dufresne. 1-28 mars 1977
J. Edmond (1973)
The Silica Budget of the Antarctic Circumpolar CurrentNature, 241
W. Broenkow (1965)
THE DISTRIBUTION OF NUTRIENTS IN THE COSTA RICA DOME IN THE EASTERN TROPICAL PACIFIC OCEANLimnology and Oceanography, 10
S. Jacobs, D. Georgi, S. Patla (1980)
Conrad 17 : Hydrographic stations, sea floor photographs, nephelometer profiles, in the Southwest Indian-Antarctic Ocean, Jan-Apr 1974
D. Nelson, J. Goering (1977)
Near-surface silica dissolution in the upwelling region off northwest AfricaDeep Sea Research, 24
T. Foster, E. Carmack (1976)
Temperature and Salinity Structure in the Weddell SeaJournal of Physical Oceanography, 6
R. Eppley, B. Peterson (1979)
Particulate organic matter flux and planktonic new production in the deep oceanNature, 282
A. Redfield, B. Ketchum, F. Richards (1963)
The influence of organisms on the composition of sea-water, 2
P. Glibert, D. Biggs, J. McCarthy (1982)
Utilization of ammonium and nitrate during austral summer in the Scotia Sea, 29
R. Weiss, H. Östlund, H. Craig (1979)
Geochemical studies of the Weddell sea, 26
C. Yentsch, D. Menzel (1963)
A method for the determination of phytoplankton chlorophyll and phaeophytin by fluorescenceDeep Sea Research and Oceanographic Abstracts, 10
A. Kamatani (1982)
Dissolution rates of silica from diatoms decomposing at various temperaturesMarine Biology, 68
C. Copin-Montégut, G. Copin-Montégut (1978)
The chemistry of particulate matter from the south Indian and Antarctic oceansDeep Sea Research, 25
J. Murphy, J. Riley (1962)
A modified single solution method for the determination of phosphate in natural watersAnalytica Chimica Acta, 27
G. Jacques, M. Fiala, L. Oriol (1984)
Démonstration, à partir de tests biologiques, de l'effet négligeable des éléments traces sur la croissance du phytoplancton antarctique, 298
G. Slawyk (1979)
13C and 15N Uptake by Phytoplankton in the Antarctic Upwelling Area: Results from the Antiprod I Cruise in the Indian Ocean SectorMarine and Freshwater Research, 30
O. Kozlova (1966)
Diatoms of the Indian and Pacific sectors of the Antarctic
A. Kamatani, J. Riley (1979)
Rate of dissolution of diatom silica walls in seawaterMarine Biology, 55
D. Lawson, D. Hurd, H. Pankratz (1978)
Silica dissolution rates of decomposing phytoplankton assemblages at various temperaturesAmerican Journal of Science, 278
D. Menzel, N. Corwin (1965)
THE MEASUREMENT OF TOTAL PHOSPHORUS IN SEAWATER BASED ON THE LIBERATION OF ORGANICALLY BOUND FRACTIONS BY PERSULFATE OXIDATION1Limnology and Oceanography, 10
M. Fukuchi (1980)
Phytoplankton chlorophyll stocks in the Antarctic OceanJournal of the Oceanographical Society of Japan, 36
G. Jacques, M. Minas (1981)
Production primaire dans le secteur indien de l'océan Antarctique en fin d'étéOceanologica Acta, 4
P. Lecorre, H. Minas (1983)
Distribution et évolution des éléments nutritifs dans le secteur indien de l'Océan Antarctique en fin de période estivaleOceanologica Acta, 6
G. Jacques, G. Cahet (1979)
Assimilation de composés organiques dissous dans le secteur antarctique de l'Ocean Indien.International Review of Hydrobiology, 64
R. Dugdale, J. Goering (1967)
UPTAKE OF NEW AND REGENERATED FORMS OF NITROGEN IN PRIMARY PRODUCTIVITY1Limnology and Oceanography, 12
S. El-Sayed, H. Jitts (1973)
Phytoplankton Production in the Southeastern Indian Ocean
W. Berger (1968)
Radiolarian Skeletons: Solution at DepthsScience, 159
R. Olson (1980)
Nitrate and ammonium uptake in Antarctic waters1Limnology and Oceanography, 25
G. Fogg (1977)
Aquatic Primary Production in the AntarcticPhilosophical Transactions of the Royal Society B, 279
227 92 92 3 3 V. Simon Centre d'Océanologie de Marseille Faculté des Sciences de Luminy (U.R.A.41) Case 901 F-13288 Marseille cédex 9 France Abstract Low primary-productivity levels in high-nutrient environments of the Southern Ocean are not yet well understood. An accurate knowledge of nutrient assimilation by phytoplankton, at the base of the pelagic food-web, therefore appears to be essential. A study of the mesoscale hydrological structure and chemical observations in the upper layers of the Indian sector of the Antarctic Ocean (Cruise MD-25 FIBEX of M.S. “Marion Dufresne”, January–February 1981) permitted us to develop a method for estimating nutrient consumption by phytoplankton. After strong vertical mixing in winter, the homogeneous Antarctic Surface Water (ASW) is, in summer, divided into two parts by a well-formed pycnocline. In the upper layer, corresponding approximately to the photic zone, we observed nutrient depletion resulting from photosynthetic activity, while the underlaying thermal minimum layer displayed unaltered winter characteristics, including nutrient concentrations typical of winter surface-water conditions. Taking into account the nutrient depletion in summer, we calculated the assimilation ratios for Antarctic phytoplankton as follows: ((NO 3 - lower)-(NO 3 - upper)):((PO 4 ≡ upper))=ΔN:ΔP=11.2±2.4 and ΔN:ΔSi=0.27±0.05. These ratios are lower than the classical Redfield ratios (ΔN:ΔP=16 and ΔN:ΔSi=1), but are in good agreement with the elementary composition of phytoplankton samples collected during the same cruise. Moreover, they agree with previously published data on stoechiometric determinations of particulate matter in surface-water samples. Besides, in the “transition layer” between the lower layer and “Warm Deep Water” (WDW), the calculated mineralization ratios were slightly higher than the assimilation ratios: ΔN:ΔP=14.6 and ΔN:ΔSi=0.37. From these ratios, it would appear that, in these surface layers of the Southern Ocean (down to 250 m), assimilation-regeneration mechanisms operate in such a way that phosphate and silicate contents decrease much more than nitrate content during the northward drift of the surface waters. The determination of assimilation ratios taking into account the nutrient depletion of the upper layer allowed us to evaluate the carbon net-production which integrates time-space variations in the photic layer over the whole early summer period. We estimated a production rate (0.4 g C m -2 d -1 ) of the same order of magnitude as the mean value obtained by the 14 C method (0.2 g C m -2 d -1 ). The theoretic silicium consumption by phytoplankton along a meridian transect, calculated using an estimated assimilation ratio of ΔC:ΔSi=1,85, indicates that the marked south-north decrease in silicate concentration in the Antarctic Surface Water would mainly result from biological activity. The silicate concentrations thus calculated were in good agreement with concentrations measured along a previous transect across the Southern Ocean.
Marine Biology – Springer Journals
Published: Aug 1, 1986
Read and print from thousands of top scholarly journals.
Already have an account? Log in
Bookmark this article. You can see your Bookmarks on your DeepDyve Library.
To save an article, log in first, or sign up for a DeepDyve account if you don’t already have one.
Copy and paste the desired citation format or use the link below to download a file formatted for EndNote
Access the full text.
Sign up today, get DeepDyve free for 14 days.
All DeepDyve websites use cookies to improve your online experience. They were placed on your computer when you launched this website. You can change your cookie settings through your browser.