Lithogenic and biogenic particle fluxes on the Lomonosov Ridge (central Arctic Ocean) and their relevance for sediment accumulation:: Vertical vs. lateral transport

被引:85
作者
Fahl, Kirsten
Noethig, Eva-Maria
机构
[1] Alfred Wegener Inst Polar & Marine Res, D-27568 Bremerhaven, Germany
[2] Alfred Wegener Inst Polar & Marine Res, D-27570 Bremerhaven, Germany
关键词
central arctic ocean; organic carbon flux; biomarker; sea ice; river discharge; lateral transport;
D O I
10.1016/j.dsr.2007.04.014
中图分类号
P7 [海洋学];
学科分类号
0707 ;
摘要
Investigations of lithogenic and biogenic particle fluxes using long-term sediment traps are still very rare in the northern high latitudes and are restricted to the arctic marginal seas and sub-arctic regions. Here data on the variability of fluxes of lithogenic matter, CaCO3, opal, and organic carbon and biomarker composition from the central Arctic Ocean are presented for a 1-year period. The study was carried out on material obtained from a long-term mooring system equipped with two multi-sampling traps, at 150 and 1550m depth, and deployed on the southern Lomonosov Ridge close to the Laptev Sea continental margin from September 1995 to August 1996. In addition, data from surface sediments were included in the study. Annual fluxes of lithogenic matter, CaCO3, opal, and particulate organic carbon were 3.9, 0.8, 2.6, and 1.5 g m(-2) y(-1), respectively, in the shallow trap and 11. 3, 0.5, 2.9, and 1.05 g m(-2) y(-1), respectively, in the deep trap. Both the shallow and the deep trap showed significant variations in vertical flux over the year. Higher values were found from mid-July to the end of October (total mass flux of 75-130 mg m(-2) d(-1) in the shallow trap and 40-225 mg m(-2) d(-1) in the deep trap). During all other months, fluxes were fairly low in both traps (most total mass flux values < 10 mg m(-2) d(-1)). The interval of increased fluxes can be separated into (1) a mid-July/August maximum caused by increased primary production as documented in high abundances of marine biomarkers and diatoms and (2) a September/October maximum caused by increased influence of Lena River discharge indicated by maximum lithogenic flux and large amounts of terrigenous/fluvial biomarkers in both traps. During September/October, total mass fluxes in the deep trap were significantly higher than in the shallow trap, suggesting a lateral sediment flux at greater depth. The lithogenic flux data also support the importance of sediment input from the Laptev Sea for the sediment accumulation on the Lomonosov Ridge on geological time scales, as indicated in sedimentary records from this region. (c) 2007 Elsevier Ltd. All rights reserved.
引用
收藏
页码:1256 / 1272
页数:17
相关论文
共 68 条
[1]   MARINE PHYTOPLANKTER FATTY ACIDS [J].
ACKMAN, RG ;
TOCHER, CS ;
MCLACHLA.J .
JOURNAL OF THE FISHERIES RESEARCH BOARD OF CANADA, 1968, 25 (08) :1603-+
[2]   Spatial and temporal variability of sea ice in the Laptev Sea:: Analyses and review of satellite passive-microwave data and model results, 1979 to 2002 [J].
Bareiss, J ;
Görgen, K .
GLOBAL AND PLANETARY CHANGE, 2005, 48 (1-3) :28-54
[4]  
Behrends M., 1999, LAND OCEAN SYSTEMS S, P265, DOI [10.1007/978-3-642-60134-7_24, DOI 10.1007/978-3-642-60134-7_24]
[5]   PRIMARY PRODUCTIVITY AND PARTICLE FLUXES ON A TRANSECT OF THE EQUATOR AT 153-DEGREES-W IN THE PACIFIC-OCEAN [J].
BETZER, PR ;
SHOWERS, WJ ;
LAWS, EA ;
WINN, CD ;
DITULLIO, GR ;
KROOPNICK, PM .
DEEP-SEA RESEARCH PART A-OCEANOGRAPHIC RESEARCH PAPERS, 1984, 31 (01) :1-11
[6]   HYDROCARBONS OF MARINE PHYTOPLANKTON [J].
BLUMER, M ;
GUILLARD, RR ;
CHASE, T .
MARINE BIOLOGY, 1971, 8 (03) :183-&
[7]   Benthic oxygen uptake, hydrolytic potentials and microbial biomass at the Arctic continental slope [J].
Boetius, A ;
Damm, E .
DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS, 1998, 45 (2-3) :239-275
[8]   Particulate organic matter in surface sediments of the Laptev Sea (Arctic Ocean): application of maceral analysis as organic-carbon-source indicator [J].
Boucsein, B ;
Stein, R .
MARINE GEOLOGY, 2000, 162 (2-4) :573-586
[9]   AN ESTIMATE OF THE MEAN FIELD OF ARCTIC SEA ICE MOTION [J].
COLONY, R ;
THORNDIKE, AS .
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS, 1984, 89 (NC6) :623-629
[10]   Satellite-observed changes in the Arctic [J].
Comiso, JC ;
Parkinson, CL .
PHYSICS TODAY, 2004, 57 (08) :38-44