English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/25477
Share/Impact:
Statistics
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:

Title

A dynamic model of oceanic sulfur (DMOS) applied to the Sargasso Sea: Simulating the dimethylsulfide (DMS) summer paradox

AuthorsVallina, Sergio M. ; Simó, Rafel ; Anderson, Thomas R.; Gabric, A.J.; Cropp, R.M.; Pacheco, J.M.
KeywordsBiogeochemical modeling
DMS summer paradox
Phytoplankton DMS exudation
Sargasso Sea
Dimethylsulfide
DMS
Issue Date6-Feb-2008
PublisherAmerican Geophysical Union
CitationJournal of Geophysical Research: Biogeosciences 113(G1): G01009 (2008)
AbstractA new one-dimensional model of DMSP/DMS dynamics (DMOS) is developed and applied to the Sargasso Sea in order to explain what drives the observed dimethylsulfide (DMS) summer paradox: a summer DMS concentration maximum concurrent with a minimum in the biomass of phytoplankton, the producers of the DMS precursor dimethylsulfoniopropionate (DMSP). Several mechanisms have been postulated to explain this mismatch: a succession in phytoplankton species composition towards higher relative abundances of DMSP producers in summer; inhibition of bacterial DMS consumption by ultraviolet radiation (UVR); and direct DMS production by phytoplankton due to UVR-induced oxidative stress. None of these hypothetical mechanisms, except for the first one, has been tested with a dynamic model. We have coupled a new sulfur cycle model that incorporates the latest knowledge on DMSP/DMS dynamics to a preexisting nitrogen/carbon-based ecological model that explicitly simulates the microbial-loop. This allows the role of bacteria in DMS production and consumption to be represented and quantified. The main improvements of DMOS with respect to previous DMSP/DMS models are the explicit inclusion of: solar-radiation inhibition of bacterial sulfur uptakes; DMS exudation by phytoplankton caused by solar-radiation-induced stress; and uptake of dissolved DMSP by phytoplankton. We have conducted a series of modeling experiments where some of the DMOS sulfur paths are turned “off” or “on,” and the results on chlorophyll-a, bacteria, DMS, and DMSP (particulate and dissolved) concentrations have been compared with climatological data of these same variables. The simulated rate of sulfur cycling processes are also compared with the scarce data available from previous works. All processes seem to play a role in driving DMS seasonality. Among them, however, solar-radiation-induced DMS exudation by phytoplankton stands out as the process without which the model is unable to produce realistic DMS simulations and reproduce the DMS summer paradox
Description23 pages, 12 figures, supporting information http://onlinelibrary.wiley.com/doi/10.1029/2007JG000415/suppinfo
Publisher version (URL)http://dx.doi.org/10.1029/2007JG000415
URI10261/25477
DOI10.1029/2007JG000415
ISSN2169-8953
E-ISSN2169-8961
Appears in Collections:(ICM) Artículos
Files in This Item:
File Description SizeFormat 
Vallina_et_al_2008.pdf1,07 MBAdobe PDFThumbnail
View/Open
Show full item record
Review this work
 

Related articles:


WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.