NITROGEN CYCLING AND CONTROLS ON DENITRIFICATION IN MESOHALINE SEDIMENTS OF CHESAPEAKE BAY

Simple item page
dc.contributor.advisorCornwell, Jeffrey Cen_US
dc.contributor.authorOwens, Michael Seanen_US
dc.contributor.departmentMarine-Estuarine-Environmental Sciencesen_US
dc.contributor.publisherDigital Repository at the University of Marylanden_US
dc.contributor.publisherUniversity of Maryland (College Park, Md.)en_US
dc.date.accessioned2009-07-03T05:35:50Z
dc.date.available2009-07-03T05:35:50Z
dc.date.issued2009en_US
dc.description.abstractNitrogen is a key nutrient in the eutrophication of coastal and estuarine systems. In shallow water systems, sediment recycling can be an important source of nutrients for phytoplankton growth. The balance between nitrogen recycling and denitrification regulates the importance of sediments as a nitrogen source. To assess controls on denitrification, we conducted intensive seasonal measurements of sediment water exchange and denitrification using sediment core incubations. Peak rates of denitrification were observed in fall and spring (>100 &mu;mol N<sub2</sub>-N m<super>-2</super> h<super-1</super>) followed by a decrease to 10 &mu;mol N m<super>-2</super> h<super-1</super> in summer. Although denitrification rates were stimulated by labile organic carbon additions from the water column, the overall efficiency of the process sharply declined as temperature increased and bottom water O<sub>2</sub> declined. Macrofauna activity was shown to enhance sediment transport of O<sub>2</sub> by >5 fold, increase organic matter decomposition and maintain a high rate of denitrification efficiency.en_US
dc.format.extent943900 bytes
dc.format.mimetypeapplication/pdf
dc.identifier.urihttp://hdl.handle.net/1903/9314
dc.language.isoen_US
dc.subject.pqcontrolledEnvironmental Sciencesen_US
dc.subject.pquncontrolledBenthic-pelagic couplingen_US
dc.subject.pquncontrolledBioirrigationen_US
dc.subject.pquncontrolledDenitrificationen_US
dc.subject.pquncontrolledHypoxiaen_US
dc.subject.pquncontrolledNitrogen Cyclingen_US
dc.subject.pquncontrolledSedimenten_US
dc.titleNITROGEN CYCLING AND CONTROLS ON DENITRIFICATION IN MESOHALINE SEDIMENTS OF CHESAPEAKE BAYen_US
dc.typeThesisen_US

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
Owens_umd_0117N_10344.pdf
Size:
921.78 KB
Format:
Adobe Portable Document Format
Download

Collections

UMD Theses and Dissertations
Biology Theses and Dissertations
MEES Theses and Dissertations