Taxon‐specific differences in C/P and N/P drawdown for phytoplankton in the Ross Sea, Antarctica

Data from 11 cruises to the Ross Sea, Antarctica show that non‐Redfield N/P and C/P drawdown ratios for diatoms and Phaeocystis antarctica were a consistent feature of the phytoplankton communities between 1990 and 1998. Ratios of N/P drawdown for waters dominated by P. antarctica ranged from 17.2–19.5, consistently exceeding the Redfield ratio of 16. Similarly, the C/P drawdown ratio for P. antarctica‐dominated waters ranged from 120–154, 13–45% greater than the Redfield ratio of 106. Waters dominated by diatoms exhibited much lower ratios than Redfield for N/P (mean = 11.9) and C/P (mean = 76.2) drawdown. There was no seasonal trend to the drawdown ratios by either taxa. Sediment trap data exhibited C/P ratios for P. antarctica‐dominated samples that were twice that for diatoms, suggesting that the large taxonomic difference in C/P drawdown ratio is expressed as a difference in particulate C/P ratio which is subsequently exported to depth.

[1]  P. Boyd,et al.  Size-fractionated primary production and nitrogen uptake during a North Atlantic phytoplankton bloom : implications for carbon export estimates , 2001 .

[2]  V. Asper,et al.  The influence of phytoplankton assemblage composition on biogeochemical characteristics and cycles in the southern Ross Sea, Antarctica , 2001 .

[3]  A. Goffart,et al.  Factors controlling the distribution of diatoms and Phaeocystis in the Ross Sea , 2000 .

[4]  R. Hecky,et al.  Total nitrogen, total phosphorus, and nutrient limitation in lakes and oceans: Is there a common relationship? , 2000 .

[5]  H. Elderfield,et al.  Oceanic Cd/P ratio and nutrient utilization in the glacial Southern Ocean , 2000, Nature.

[6]  D. H. Robinson,et al.  Phytoplankton taxonomic variability in nutrient utilization and primary production in the Ross Sea , 2000 .

[7]  D. H. Robinson,et al.  Rapid and early export of Phaeocystis antarctica blooms in the Ross Sea, Antarctica , 2000, Nature.

[8]  M. Pahlow,et al.  Temporal trends in deep ocean redfield ratios. , 2000, Science.

[9]  Dennis A. Hansell,et al.  Nutrient and carbon removal ratios and fluxes in the Ross Sea , 2000 .

[10]  D. H. Robinson,et al.  Phytoplankton community structure and the drawdown of nutrients and CO2 in the southern ocean , 1999, Science.

[11]  R. Dunbar,et al.  Water column sediment fluxes in the Ross Sea, Antarctica: Atmospheric and sea ice forcing , 1998 .

[12]  M. Brzezinski,et al.  Silicon-isotope composition of diatoms as an indicator of past oceanic change , 1998, Nature.

[13]  Taro Takahashi,et al.  Primary productivity and nutrient utilization ratios in the Pacific sector of the Southern Ocean based on seasonal changes in seawater chemistry , 1998 .

[14]  Syukuro Manabe,et al.  Simulated response of the ocean carbon cycle to anthropogenic climate warming , 1998, Nature.

[15]  R. Chervin,et al.  Physical forcing of phytoplankton dynamics in the southwestern Ross Sea (Paper 97JC02326) , 1998 .

[16]  D. Sigman,et al.  Contribution of Southern Ocean surface-water stratification to low atmospheric CO2 concentrations during the last glacial period , 1997, Nature.

[17]  Andrew G. Dickson,et al.  Protocols for the Joint Global Ocean Flux Study (JGOFS) Core Measurements , 1996 .

[18]  Jorge L. Sarmiento,et al.  Redfield ratios of remineralization determined by nutrient data analysis , 1994 .

[19]  John H. Martin.  glacial-interglacial Co2 change : the iron hypothesis , 1990 .

[20]  A. Royer,et al.  Ice age aerosol content from East Antarctic ice core samples and past wind strength , 1981, Nature.