NET COMMUNITY PRODUCTION
; MERTZ GLACIER REGION
; SOUTHERN-OCEAN
; ADELIE LAND
; DELTA-PCO(2) VARIATION
; MARINE PRODUCTIVITY
; DISSOLVED IRON
; CLIMATE-CHANGE
; ROSS SEA
; CARBON
WOS学科分类:
Oceanography
WOS研究方向:
Oceanography
英文摘要:
In the Southern Ocean, polynyas exhibit enhanced rates of primary productivity and represent large seasonal sinks for atmospheric CO2. Three contrasting east Antarctic polynyas were visited in late December to early January 2017: the Dalton, Mertz, and Ninnis polynyas. In the Mertz and Ninnis polynyas, phytoplankton biomass (average of 322 and 354mg chlorophyll a (Chl a)/m(2), respectively) and net community production (5.3 and 4.6mol C/m(2), respectively) were approximately 3 times those measured in the Dalton polynya (average of 122mg Chl a/m(2) and 1.8mol C/m(2)). Phytoplankton communities also differed between the polynyas. Diatoms were thriving in the Mertz and Ninnis polynyas but not in the Dalton polynya, where Phaeocystis antarctica dominated. These strong regional differences were explored using physiological, biological, and physical parameters. The most likely drivers of the observed higher productivity in the Mertz and Ninnis were the relatively shallow inflow of iron-rich modified Circumpolar Deep Water onto the shelf as well as a very large sea ice meltwater contribution. The productivity contrast between the three polynyas could not be explained by (1) the input of glacial meltwater, (2) the presence of Ice Shelf Water, or (3) stratification of the mixed layer. Our results show that physical drivers regulate the productivity of polynyas, suggesting that the response of biological productivity and carbon export to future change will vary among polynyas.
1.Univ Tasmania, Inst Marine & Antarctic Studies, Hobart, Tas, Australia 2.Univ Tasmania, Australian Res Council Antarctic Gateway Partners, Hobart, Tas, Australia 3.Norwegian Polar Res Inst, Fram Ctr, Tromso, Norway 4.Univ Tasmania, Antarctic Climate & Ecosyst Cooperat Res Ctr, Hobart, Tas, Australia 5.Virginia Inst Marine Sci, Coll William & Mary, Williamsburg, VA USA 6.Univ Tasmania, Australian Res Council Ctr Excellence Climate Ext, Hobart, Tas, Australia 7.Commonwealth Sci & Ind Res Org, Oceans & Atmosphere, Hobart, Tas, Australia 8.Edith Cowan Univ, Sch Sci, Joondalup, WA, Australia 9.Edith Cowan Univ, Ctr Marine Ecosyst Res, Joondalup, WA, Australia 10.CSIRO, Ctr Southern Hemisphere Oceans Res, Hobart, Tas, Australia 11.Univ Autonoma Barcelona, Inst Ciencia & Tecnol Ambientals, Bellaterra, Spain 12.Univ Autonoma Barcelona, Dept Fis, Bellaterra, Spain 13.Woods Hole Oceanog Inst, Woods Hole, MA 02543 USA
Recommended Citation:
Moreau, S.,Lannuzel, D.,Janssens, J.,et al. Sea Ice Meltwater and Circumpolar Deep Water Drive Contrasting Productivity in Three Antarctic Polynyas[J]. JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS,2019-01-01,124(5):2943-2968