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# Assessing the apparent imbalance between geochemical and biochemical indicators of meso- and bathypelagic biological activity: What the @$?! is wrong with present calculations of carbon budgets? Burd, Adrian B., Hansell, Dennis A., Steinberg, Deborah K., Anderson, Thomas R., Arístegui, Javier, Baltar, Federico, Beaupré, Steven R., Buesseler, Ken O., DeHairs, Frank, Jackson, George A., Kadko, David C., Koppelmann, Rolf, Lampitt, Richard S., Nagata, Toshi, Reinthaler, Thomas, Robinson, Carol, Robison, Bruce H., Tamburini, Christian and Tanaka, Tsuneo (2010) Assessing the apparent imbalance between geochemical and biochemical indicators of meso- and bathypelagic biological activity: What the @$?! is wrong with present calculations of carbon budgets? Deep Sea Research Part II: Topical Studies in Oceanography, 57 (16), 1557-1571.

Record type: Article

## Abstract

Metabolic activity in the water column below the euphotic zone is ultimately fuelled by the vertical flux of organic material from the surface. Over time, the deep ocean is presumably at steady state, with sources and sinks balanced. But recently compiled global budgets and intensive local field studies suggest that estimates of metabolic activity in the dark ocean exceed the influx of organic substrates. This imbalance indicates either the existence of unaccounted sources of organic carbon or that metabolic activity in the dark ocean is being over-estimated. Budgets of organic carbon flux and metabolic activity in the dark ocean have uncertainties associated with environmental variability, measurement capabilities, conversion parameters, and processes that are not well sampled. We present these issues and quantify associated uncertainties where possible, using a Monte Carlo analysis of a published data set to determine the probability that the imbalance can be explained purely by uncertainties in measurements and conversion factors. A sensitivity analysis demonstrates that the bacterial growth efficiencies and assumed cell carbon contents have the greatest effects on the magnitude of the carbon imbalance. Two poorly quantified sources, lateral advection of particles and a population of slowly settling particles, are discussed as providing a means of closing regional carbon budgets. Finally, we make recommendations concerning future research directions to reduce important uncertainties and allow a better determination of the magnitude and causes of the unbalanced carbon budgets.

Published date: 15 August 2010
Organisations: Marine Systems Modelling, Marine Biogeochemistry

## Identifiers

Local EPrints ID: 160655
URI: http://eprints.soton.ac.uk/id/eprint/160655
ISSN: 0967-0645
PURE UUID: 20dd8617-caab-4ba2-8310-1f0e75271c14

## Catalogue record

Date deposited: 16 Jul 2010 12:10

## Contributors

Author: Dennis A. Hansell
Author: Deborah K. Steinberg
Author: Thomas R. Anderson
Author: Javier Arístegui
Author: Federico Baltar
Author: Steven R. Beaupré
Author: Ken O. Buesseler
Author: Frank DeHairs
Author: George A. Jackson
Author: Rolf Koppelmann
Author: Richard S. Lampitt
Author: Toshi Nagata
Author: Thomas Reinthaler
Author: Carol Robinson
Author: Bruce H. Robison
Author: Christian Tamburini
Author: Tsuneo Tanaka