Warming and organic matter sources impact the proportion of dissolved to total activities in marine extracellular enzymatic rates

Handle URI:
http://hdl.handle.net/10754/623442
Title:
Warming and organic matter sources impact the proportion of dissolved to total activities in marine extracellular enzymatic rates
Authors:
Baltar, Federico ( 0000-0001-8907-1494 ) ; Moran, Xose Anxelu G. ( 0000-0002-9823-5339 ) ; Lønborg, Christian
Abstract:
Extracellular enzymatic activities (EEAs) are the rate-limiting step in the degradation of organic matter. Extracellular enzymes can be found associated to cells or dissolved in the surrounding water. The proportion of cell-free EEA constitutes in many marine environments more than half of the total activity. This high proportion causes an uncoupling between hydrolysis rates and the actual bacterial activity. However, we do not know what factors control the proportion of dissolved relative to total EEA, nor how this may change in the future ocean. To resolve this, we performed laboratory experiments with water from the Great Barrier Reef (Australia) to study the effects of temperature and dissolved organic matter sources on EEA and the proportion of dissolved EEA. We found that warming increases the rates of organic matter hydrolysis and reduces the proportion of dissolved relative to total EEA. This suggests a potential increase of the coupling between organic matter hydrolysis and heterotrophic activities with increasing ocean temperatures, although strongly dependent on the organic matter substrates available. Our study suggests that local differences in the organic matter composition in tropical coastal ecosystems will strongly affect the proportion of dissolved EEA in response to ocean warming.
KAUST Department:
Biological and Environmental Sciences and Engineering (BESE) Division; Marine Science Program; Red Sea Research Center (RSRC)
Citation:
Baltar F, Morán XAG, Lønborg C (2017) Warming and organic matter sources impact the proportion of dissolved to total activities in marine extracellular enzymatic rates. Biogeochemistry 133: 307–316. Available: http://dx.doi.org/10.1007/s10533-017-0334-9.
Publisher:
Springer Nature
Journal:
Biogeochemistry
Issue Date:
19-Apr-2017
DOI:
10.1007/s10533-017-0334-9
Type:
Article
ISSN:
0168-2563; 1573-515X
Sponsors:
The authors would like to thank the SeaSim team at AIMS for the help with setting up the experiments. The study was co-financed by the AIMS visiting fellowship program as part of the capability development fund (CDF). F. Baltar was supported by a University of Otago Research Grant.
Additional Links:
http://link.springer.com/article/10.1007/s10533-017-0334-9
Appears in Collections:
Articles; Red Sea Research Center (RSRC); Marine Science Program; Biological and Environmental Sciences and Engineering (BESE) Division

Full metadata record

DC FieldValue Language
dc.contributor.authorBaltar, Federicoen
dc.contributor.authorMoran, Xose Anxelu G.en
dc.contributor.authorLønborg, Christianen
dc.date.accessioned2017-05-09T12:54:46Z-
dc.date.available2017-05-09T12:54:46Z-
dc.date.issued2017-04-19en
dc.identifier.citationBaltar F, Morán XAG, Lønborg C (2017) Warming and organic matter sources impact the proportion of dissolved to total activities in marine extracellular enzymatic rates. Biogeochemistry 133: 307–316. Available: http://dx.doi.org/10.1007/s10533-017-0334-9.en
dc.identifier.issn0168-2563en
dc.identifier.issn1573-515Xen
dc.identifier.doi10.1007/s10533-017-0334-9en
dc.identifier.urihttp://hdl.handle.net/10754/623442-
dc.description.abstractExtracellular enzymatic activities (EEAs) are the rate-limiting step in the degradation of organic matter. Extracellular enzymes can be found associated to cells or dissolved in the surrounding water. The proportion of cell-free EEA constitutes in many marine environments more than half of the total activity. This high proportion causes an uncoupling between hydrolysis rates and the actual bacterial activity. However, we do not know what factors control the proportion of dissolved relative to total EEA, nor how this may change in the future ocean. To resolve this, we performed laboratory experiments with water from the Great Barrier Reef (Australia) to study the effects of temperature and dissolved organic matter sources on EEA and the proportion of dissolved EEA. We found that warming increases the rates of organic matter hydrolysis and reduces the proportion of dissolved relative to total EEA. This suggests a potential increase of the coupling between organic matter hydrolysis and heterotrophic activities with increasing ocean temperatures, although strongly dependent on the organic matter substrates available. Our study suggests that local differences in the organic matter composition in tropical coastal ecosystems will strongly affect the proportion of dissolved EEA in response to ocean warming.en
dc.description.sponsorshipThe authors would like to thank the SeaSim team at AIMS for the help with setting up the experiments. The study was co-financed by the AIMS visiting fellowship program as part of the capability development fund (CDF). F. Baltar was supported by a University of Otago Research Grant.en
dc.publisherSpringer Natureen
dc.relation.urlhttp://link.springer.com/article/10.1007/s10533-017-0334-9en
dc.rightsThe final publication is available at Springer via http://dx.doi.org/10.1007/s10533-017-0334-9en
dc.subjectExtracellular enzymatic activityen
dc.subjectDissolved enzymesen
dc.subjectWarmingen
dc.subjectOrganic matteren
dc.titleWarming and organic matter sources impact the proportion of dissolved to total activities in marine extracellular enzymatic ratesen
dc.typeArticleen
dc.contributor.departmentBiological and Environmental Sciences and Engineering (BESE) Divisionen
dc.contributor.departmentMarine Science Programen
dc.contributor.departmentRed Sea Research Center (RSRC)en
dc.identifier.journalBiogeochemistryen
dc.eprint.versionPost-printen
dc.contributor.institutionNIWA/University of Otago Research Centre for Oceanography, Dunedin, New Zealanden
dc.contributor.institutionDepartment of Marine Science, University of Otago, Dunedin, New Zealanden
dc.contributor.institutionAustralian Institute of Marine Science, Townsville, Australiaen
kaust.authorMoran, Xose Anxelu G.en
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