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domingo, 5 de julio de 2015

National Science Foundation - Methane-eating microorganisms help regulate emissions from wetlands .- Microorganismos que se alimentan de metano ayudan a regular las emisiones de los humedales

Hola amigos: A VUELO DE UN QUINDE EL BLOG., hemos recibido información de la Fundación Nacional de Ciencias de Los Estados Unidos, que sus cientíicos han descubierto que microorganismos que se alimentan del metano ayudan a regular las emisiones en los humedales.
NSF, nos dice: A pesar de que ocupan una pequeña fracción de la superficie de la Tierra, los humedales de agua dulce son la mayor fuente natural de metano emitido a la atmósfera. Una nueva investigación identifica un proceso inesperado que actúa como un guardián clave en la regulación de las emisiones de metano procedentes de estos ambientes de agua dulce.
Los resultados del estudio se publican esta semana en la revista Nature Communications por el biólogo Samantha Joye, de la Universidad de Georgia y colegas.
Los investigadores informan de que las altas tasas de anaeróbico (sin oxígeno) la oxidación del metano en los humedales de agua dulce reducir sustancialmente las emisiones atmosféricas de metano.

More information.....

Without this process, methane emissions from freshwater wetlands could be 30 to 50 percent higher:
Sin este proceso, las emisiones de metano de los humedales de agua dulce podría ser de 30 a 50 por ciento más alto
Scientist in lake collecting sediment samples in Maine
Scientists collect sediment samples in Maine's Acadia National Park.
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June 30, 2015
Though they occupy a small fraction of Earth's surface, freshwater wetlands are the largest natural source of methane emitted into the atmosphere. New research identifies an unexpected process that acts as a key gatekeeper in regulating methane emissions from these freshwater environments.
The study results are published this week in the journal Nature Communications by biologist Samantha Joye of the University of Georgia and colleagues.
The researchers report that high rates of anaerobic (no oxygen) methane oxidation in freshwater wetlands substantially reduce atmospheric emissions of methane.

New attention

The process of anaerobic methane oxidation was once considered insignificant in freshwater wetlands, but scientists now think very differently about its importance.
"Some microorganisms actually eat methane, and recent decades have seen an explosion in our understanding of the way they do this," says Matt Kane, program director in the National Science Foundation's Division of Environmental Biology, which funded the research. "These researchers demonstrate that if it were not for an unusual group of methane-eating microbes that live in freshwater wetlands, far more methane would be released into the atmosphere."
Although anaerobic methane oxidation in freshwater has been gathering scientific attention, the environmental relevance of this process was unknown until recently, Joye says.
"This paper reports a previously unrecognized sink for methane in freshwater sediments, soils and peats: microbially-mediated anaerobic oxidation of methane," she says. "The fundamental importance of this process in freshwater wetlands underscores the critical role that anaerobic oxidation of methane plays on Earth, even in freshwater habitats."
Without this process, Joye says, methane emissions from freshwater wetlands could be 30 to 50 percent greater.

Comparison of wetlands

The researchers investigated the anaerobic oxidation process in freshwater wetlands in three regions: the freshwater peat soils of the Florida Everglades; a coastal organic-rich wetland in Acadia National Park, Maine; and a tidal freshwater wetland in coastal Georgia.
All three sites were sampled over multiple seasons.
The anaerobic oxidation of methane was coupled to some extent with sulfate reduction. Rising sea levels, for example, would result in increased sulfate, which could fuel greater rates of anaerobic oxidation.
Similarly, with saltwater intrusion into coastal freshwater wetlands, increasing sulfate inhibits microbial methane formation, or methanogenesis.
So while freshwater wetlands are known to be significant methane sources, their low sulfate concentrations previously led most researchers to conclude that anaerobic oxidation of methane was not important in these regions.

Crucial process

The new findings show that if not for the anaerobic methane oxidation process, freshwater environments would account for an even greater portion of the global methane budget.
"The process of anaerobic oxidation of methane in freshwater wetlands appears to be different than what we know about this process in marine sediments," Joye says. "There could be unique biochemistry at work."
Adds Katherine Segarra, an oceanographer at the U.S. Department of the Interior's Bureau of Ocean Energy Management and co-author of the paper: "This study furthers the understanding of the global methane budget, and may have ramifications for the development of future greenhouse gas models."
Additional financial support for the research was provided by the Deutsche Forschungsgemeinschaft via the Research Center/Cluster of Excellence at the MARUM Center for Marine Environmental Sciences and department of geosciences at the University of Bremen, Germany.
--  Cheryl Dybas, NSF (703) 292-7734 cdybas@nsf.gov
--  Alan Flurry, University of Georgia (706) 542-3331 aflurry@uga.edu
Samantha Joye
Christof Meile
Vladimir Samarkin

Related Institutions/Organizations University of Georgia Research Foundation Inc

Related Awards #0717189 Temperature Driven Decoupling of Carbon Cycling in Freshwater Sediments and the Relative Production and Flux of Methane Versus Carbon Dioxide

Total Grants $672,990
  freshwater wetlands in Acadia National Park
Acadia National Park is dotted with freshwater wetlands.
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wetlands covered in ice and snow.
Same wetland as above, covered in ice and snow. Researchers are studying what goes on beneath.
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Woman sampling the overlying water of a frozen wetland in Acadia National Park.
Researchers sample the overlying water of a frozen wetland in Acadia National Park.
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View from an airboat used to collect samples in the Florida Everglades.
Scientists use an airboat to collect samples in the Florida Everglades.
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Freshwater wetland in coastal Georgia during  winter
Researchers collected samples from freshwater wetlands in coastal Georgia during a winter trip.
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The National Science Foundation (NSF)
Guillermo Gonzalo Sánchez Achutegui
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