Labile and Recalcitrant Organic Matter Utilization by River Biofilm Under Increasing Water Temperature
dc.contributor.author
dc.date.accessioned
2015-11-18T11:39:31Z
dc.date.available
2015-11-18T11:39:31Z
dc.date.issued
2012
dc.identifier.issn
0095-3628
dc.identifier.uri
dc.description.abstract
Microbial biofilms in rivers contribute to the decomposition of the available organic matter which typically shows changes in composition and bioavailability due to their origin, seasonality, and watershed characteristics. In the context of global warming, enhanced biofilm organic matter decomposition would be expected but this effect could be specific when either a labile or a recalcitrant organic matter source would be available. A laboratory experiment was performed to mimic the effect of the predicted increase in river water temperature (+4 °C above an ambient temperature) on the microbial biofilm under differential organic matter sources. The biofilm microbial community responded to higher water temperature by increasing bacterial cell number, respiratory activity (electron transport system) and microbial extracellular enzymes (extracellular enzyme activity). At higher temperature, the phenol oxidase enzyme explained a large fraction of respiratory activity variation suggesting an enhanced microbial use of degradation products from humic substances. The decomposition of hemicellulose (β-xylosidase activity) seemed to be also favored by warmer conditions. However, at ambient temperature, the enzymes highly responsible for respiration activity variation were β-glucosidase and leu-aminopeptidase, suggesting an enhanced microbial use of polysaccharides and peptides degradation products. The addition of labile dissolved organic carbon (DOC; dipeptide plus cellobiose) caused a further augmentation of heterotrophic biomass and respiratory activity. The changes in the fluorescence index and the ratio Abs250/total DOC indicated that higher temperature accelerated the rates of DOC degradation. The experiment showed that the more bioavailable organic matter was rapidly cycled irrespective of higher temperature while degradation of recalcitrant substances was enhanced by warming. Thus, pulses of carbon at higher water temperature might have consequences for DOC processing
dc.description.sponsorship
This study was funded by projects CGL2007-65549/BOS, CGL2008-05618-C02/BOS, CGL2011-30151-C02-01, and SCARCE (Consolider-Ingenio CSD2009-00065) of the Spanish Ministry of Economy and Competitiveness
dc.format.mimetype
application/pdf
dc.language.iso
eng
dc.publisher
Springer Verlag
dc.relation
info:eu-repo/grantAgreement/MICINN//CGL2011-30151-C02-01/ES/HOT-SPOTS BIOGEOQUIMICOS Y MICROBIANOS EN RIOS MEDITERRANEOS. ESTRUCTURA Y FUNCION DEL BIOFILM MICROBIANO Y SU IMPLICACION EN LA GESTION DE LA CALIDAD DE LAS AGUAS FLUVIALES/
info:eu-repo/grantAgreement/MEC//CGL2007-65549/ES/EFECTOS DE EPISODIOS DE INTERRUPCION DEL FLUJO SOBRE LA CONTINUIDAD ESTRUCTURAL Y FUNCIONAL DE SISTEMAS FLUVIALES/
info:eu-repo/grantAgreement/MICINN//CGL2008-05618-C02-01/ES/EFECTOS DEL CALENTAMIENTO Y LA TEMPORALIDAD EN EL PROCESADO DE MATERIA ORGANICA EN RIOS.1-BIOFILM/
info:eu-repo/grantAgreement/MICINN//CSD2009-00065/ES/Evaluación y predicción de los efectos del cambio global en la cantidad y la calidad del agua en ríos ibéricos/
dc.relation.isformatof
Reproducció digital del document publicat a: http://dx.doi.org/10.1007/s00248-012-0062-6
dc.relation.ispartof
© Microbial Ecology, 2012, vol. 64, núm. 3, p. 593-604
dc.relation.ispartofseries
Articles publicats (D-CCAA)
dc.rights
Tots els drets reservats
dc.subject
dc.title
Labile and Recalcitrant Organic Matter Utilization by River Biofilm Under Increasing Water Temperature
dc.type
info:eu-repo/semantics/article
dc.rights.accessRights
info:eu-repo/semantics/embargoedAccess
dc.embargo.terms
Cap
dc.date.embargoEndDate
info:eu-repo/date/embargoEnd/2026-01-01
dc.type.version
info:eu-repo/semantics/publishedVersion
dc.identifier.doi
dc.identifier.idgrec
016738
dc.contributor.funder
dc.relation.ProjectAcronym
dc.identifier.eissn
1432-184X