Vertical Flux of Biogenic Carbon in the Ocean: Is There Food Web Control?
Models of biogenic carbon (BC) flux assume that short herbivorous food chains lead to high export, whereas complex microbial or omnivorous food webs lead to recycling and low export, and that export of BC from the euphotic zone equals new production (NP). In the Gulf of St. Lawrence, particulate organic carbon fluxes were similar during the spring phytoplankton bloom, when herbivory dominated, and during nonbloom conditions, when microbial and omnivorous food webs dominated. In contrast, NP was 1.2 to 161 times greater during the bloom than after it. Thus, neither food web structure nor NP can predict the magnitude or patterns of BC export, particularly on time scales over which the ocean is in nonequilibrium conditions.
Rivkin
RB
R. B. Rivkin, D. Deibel, K. Crocker, P. Matthews, Ocean Sciences Centre, Memorial University of Newfoundland, St. John's, NF A1C 5S7, Canada. L. Legendre, J.-E. Tremblay, B. Klein, C. Lovejoy, F. Mesple, Departement de biologie, Universite Laval, Quebec, QC G1K 7P4, Canada. S. Roy, INRS-Oceanologie, 310 Alee des Ursulines, Rimouski, QC G5L 3A1, Canada. N. Silverberg, N. Romero, C. Savenkoff, A. Vezina, J.-C. Therriault, C. Berube, Institut Maurice-Lamontagne, Ministere des Peches et des Oceans, Casse Postale 1000, Mont-Joli, G5H 3Z4 QC, Canada. M. R. Anderson, Marine Habitat Research, Science Branch, Fisheries and Oceans Canada, Newfoundland Region, Post Office Box 5667, St. John's, NF A1C 5X1, Canada. J. Wesson and R. G. Ingram, Department of Atmospheric and Oceanic Sciences, McGill University, 805 Sherbrooke Street West, Montreal, QC H3A 2K6, Canada.
Legendre
L
Deibel
D
Tremblay
JE
Klein
B
Crocker
K
Roy
S
Silverberg
N
Lovejoy
C
Mesple
F
Romero
N
Anderson
MR
Matthews
P
Savenkoff
C
Vezina
A
Therriault
JC
Wesson
J
Berube
C
Ingram
RG