Physical control of chlorophyll a, POC, and TPN distributions in the pack ice of the Ross Sea, Antarctica -: art. no. 3316

被引:53
作者
Arrigo, KR
Robinson, DH
Dunbar, RB
Leventer, AR
Lizotte, MP
机构
[1] Stanford Univ, Dept Geophys, Stanford, CA 94305 USA
[2] San Francisco State Univ, Romberg Tiburon Ctr, Tiburon, CA USA
[3] Colgate Univ, Dept Geol, Hamilton, NY 13346 USA
[4] Univ Wisconsin, Dept Biol & Microbiol, Oshkosh, WI 54901 USA
关键词
sea ice; algae; Antarctic; nutrients; ecosystem;
D O I
10.1029/2001JC001138
中图分类号
P7 [海洋学];
学科分类号
0707 ;
摘要
The pack ice ecosystem of the Ross Sea was investigated along a 1470-km north-south transect during the spring 1998 oceanographic program Research on Ocean-Atmosphere Variability and Ecosystem Response in the Ross Sea (ROAVERRS). Snow and sea ice thickness along the transect varied latitudinally, with thinner snow and ice at the northern ice edge and thin new ice in the vicinity of the Ross Sea polynya. Relative to springtime observations in other sea ice regions, algal chlorophyll a (Chl a) concentrations were low. In contrast, particulate organic carbon (POC), total particulate nitrogen (TPN), and POC:Chl a were all high, indicating either that the ice contained substantial amounts of detritus or nonphotosynthetic organisms, or that the algae had a high POC: Chl a ratio. The abundance of Chl a, POC, and TPN in the sea ice was related to ice age and thickness, as well as to snow depth: older ice had thinner snow cover and contained higher algal biomass while new ice in the polynya had lower biomass. Older pack ice was dominated by diatoms (particularly Fragilariopsis cylindrus) and had vertical distributions of Chl a, POC, and TPN that were related to salinity, with higher biomass at the ice-water interface. Fluorescence-based measurements of photosynthetic competence (Fv/Fm) were higher at ice-water interfaces, and photosynthesis-irradiance characteristics measured for bottom ice algae were comparable to those measured in pack ice communities of other regions. Nutrient concentrations in extracted sea ice brines showed depletion of silicate and nitrate, depletion or regeneration of phosphate and nitrite, and production of ammonium when normalized to seawater salinity; however, concentrations of dissolved inorganic nitrogen, phosphorous, and silica were typically above levels likely to limit algal growth. In areas where pack ice and snow cover were thickest, light levels could be limiting to algal photosynthesis. Enrichment of delta(13) C-POC in the sea ice was correlated with the accumulation of POC, suggesting that carbon sources for photosynthesis might shift in response to decreasing CO2 supply. Comparisons between new ice and underlying waters showed similar algal species dominance (Phaeocystis antarctica) implying incorporation of phytoplankton, with substantially higher POC and TPN concentrations in the ice.
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页数:23
相关论文
共 95 条
[11]   Physical forcing of phytoplankton dynamics in the southwestern Ross Sea [J].
Arrigo, KR ;
Weiss, AM ;
Smith, WO .
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS, 1998, 103 (C1) :1007-1021
[12]  
BRICAUD A, 1990, LIMNOL OCEANOGR, V35, P69
[13]  
BROMWICH DH, 1992, MON WEATHER REV, V120, P1940, DOI 10.1175/1520-0493(1992)120<1940:SOOKWP>2.0.CO
[14]  
2
[15]   ENERGY-DISTRIBUTION IN PHOTO-CHEMICAL APPARATUS OF PHOTOSYNTHESIS [J].
BUTLER, WL .
ANNUAL REVIEW OF PLANT PHYSIOLOGY AND PLANT MOLECULAR BIOLOGY, 1978, 29 :345-378
[16]   Microzooplankton herbivory in the Ross Sea, Antarctica [J].
Caron, DA ;
Dennett, MR ;
Lonsdale, DJ ;
Moran, DM ;
Shalapyonok, L .
DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY, 2000, 47 (15-16) :3249-3272
[17]   Deriving long-term time series of sea ice cover from satellite passive-microwave multisensor data sets [J].
Cavalieri, DJ ;
Parkinson, CL ;
Gloersen, P ;
Comiso, JC ;
Zwally, HJ .
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS, 1999, 104 (C7) :15803-15814
[18]   CHANGES IN THE SALINITY AND POROSITY OF SEA-ICE SAMPLES DURING SHIPPING AND STORAGE [J].
COX, GFN ;
WEEKS, WF .
JOURNAL OF GLACIOLOGY, 1986, 32 (112) :371-375
[19]   Diatom assemblages in surface sediments of the Ross Sea: relationship to present oceanographic conditions [J].
Cunningham, WL ;
Leventer, A .
ANTARCTIC SCIENCE, 1998, 10 (02) :134-146
[20]  
Dieckmann GS, 1998, ANTARCT RES SER, V73, P85