Near-bottom particle flux in the abyssal northeast Atlantic

被引:35
作者
Lampitt, RS
Newton, PP
Jickells, TD
Thomson, J
King, P
机构
[1] Southampton Oceanog Ctr, Southampton SO14 3ZH, Hants, England
[2] Univ E Anglia, Sch Environm Sci, Norwich NR4 7TJ, Norfolk, England
关键词
D O I
10.1016/S0967-0645(00)00016-3
中图分类号
P7 [海洋学];
学科分类号
0707 ;
摘要
During a 17-month study at a site on the Porcupine Abyssal Plain of the northeast Atlantic (approx. 48 degrees N 20 degrees W), the downward flux of particulate material within and above the benthic nepheloid layer (BNL) was measured using sediment traps 1455 m above bottom (mab) (3100m depth) and 90 mab (4465 m depth). Flux at 90 mab is usually higher than the primary flux at 3100m depth, and this enhancement is especially pronounced during the winter. The additional material found in the near-bottom trap comprises recently deposited resuspended material (rebound flux), but with an admixture of refractory sediment. It is unlikely that scavenging of either BNL particles or dissolved material contributes greatly to the near-bottom flux. Fluxes of metal tracers ((232)Th and Al) and cyanobacteria into traps were used to examine the process of resuspension. The ratio of tracer flux at 90 mab to that at 3100m depth was taken as a measure of the strength of the resuspension process (the resuspension factor RF) and reflects clearly the enhanced resuspension in winter. This seasonal variation appears to be related to both the magnitude of near-bottom currents and to the wave height at the surface 40 days before. It is also possible that recently deposited material forms a partly cohesive blanket on the sediment surface that restricts resuspension to the benthic boundary layer. (C) 2000 Elsevier Science Ltd. All rights reserved.
引用
收藏
页码:2051 / 2071
页数:21
相关论文
共 63 条
[31]  
Kroencke Ingrid, 1994, Polar Biology, V14, P423
[32]   Particle flux in deep seas: regional characteristics and temporal variability [J].
Lampitt, RS ;
Antia, AN .
DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS, 1997, 44 (08) :1377-1403
[33]   EVIDENCE FOR THE SEASONAL DEPOSITION OF DETRITUS TO THE DEEP-SEA FLOOR AND ITS SUBSEQUENT RESUSPENSION [J].
LAMPITT, RS .
DEEP-SEA RESEARCH PART A-OCEANOGRAPHIC RESEARCH PAPERS, 1985, 32 (08) :885-897
[34]   THE CONTRIBUTION OF DEEP-SEA MACROPLANKTON TO ORGANIC REMINERALIZATION - RESULTS FROM SEDIMENT TRAP AND ZOOPLANKTON STUDIES OVER THE MADEIRA ABYSSAL-PLAIN [J].
LAMPITT, RS .
DEEP-SEA RESEARCH PART A-OCEANOGRAPHIC RESEARCH PAPERS, 1992, 39 (2A) :221-233
[35]   Material supply to the European continental slope: A budget based on benthic oxygen demand and organic supply [J].
Lampitt, RS ;
Raine, RCT ;
Billett, DSM ;
Rice, AL .
DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS, 1995, 42 (11-12) :1865-+
[36]   MARINE SNOW STUDIES IN THE NORTHEAST ATLANTIC-OCEAN - DISTRIBUTION, COMPOSITION AND ROLE AS A FOOD SOURCE FOR MIGRATING PLANKTON [J].
LAMPITT, RS ;
WISHNER, KF ;
TURLEY, CM ;
ANGEL, MV .
MARINE BIOLOGY, 1993, 116 (04) :689-702
[37]  
LARSON RJ, 1992, B MAR SCI, V51, P277
[38]  
LISITZIN AP, 1996, PUB AM GEOPHYSICAL U
[39]   BACTERIA AND CYANOBACTERIA ASSOCIATED WITH PHYTODETRITUS IN THE DEEP-SEA [J].
LOCHTE, K ;
TURLEY, CM .
NATURE, 1988, 333 (6168) :67-69
[40]   DEPOSITIONAL FLUXES, PALAEOPRODUCTIVITY, AND ICE RAFTING IN THE NE ATLANTIC OVER THE PAST 30 KA [J].
MANIGHETTI, B ;
MCCAVE, IN .
PALEOCEANOGRAPHY, 1995, 10 (03) :579-592