FACTORS INFLUENCING SURFACE ATMOSPHERE EXCHANGE OF GASEOUS ELEMENTAL MERCURY IN WESTERN MARYLAND
| dc.contributor.advisor | Castro, Mark S | en_US |
| dc.contributor.author | Moore, Christopher Warren | en_US |
| dc.contributor.department | Marine-Estuarine-Environmental Sciences | en_US |
| dc.contributor.publisher | Digital Repository at the University of Maryland | en_US |
| dc.contributor.publisher | University of Maryland (College Park, Md.) | en_US |
| dc.date.accessioned | 2011-10-08T05:36:28Z | |
| dc.date.available | 2011-10-08T05:36:28Z | |
| dc.date.issued | 2011 | en_US |
| dc.description.abstract | The purpose of this study was to examine the dynamics of the surface - atmosphere exchange of gaseous elemental mercury (GEM) in western Maryland. The site studied was the Piney Reservoir Ambient Air Monitoring Station (PRAAMS) in Garrett County. I used several different techniques to quantify the exchange, including a soil pore air sampling system that I developed, dynamic flux chambers, and the modified Bowen ratio (MBR) technique. I found that GEM exchange dynamics vary widely from the small scale (< 1 m2) of the flux chambers to the large scale of the MBR technique. When I scaled the flux chamber measurements up to the annual time scale, I predicted a net GEM emission of 2.0 to 5.3 g m2 yr-1 to the atmosphere from PRAAMS, while with the MBR technique I estimated a GEM deposition of 3.3 g m2 y-1. The differences in these estimates highlight the difficulties with measuring the exchange of a substance that can be both deposited to and emitted from soils. It also shows how uncertain the current estimates of this exchange can be. On the other hand, I was able to quantify soil redox potential as an important driver of GEM fluxes and soil pore total gaseous mercury (TGM) concentrations. This had not been previously reported. I was also able to show the importance of soil organic matter (SOM) and soil pore TGM concentration gradients on the surface -atmosphere exchange of GEM. This work opens the door for other studies on the dynamics of GEM fluxes in all sites with background concentrations of GEM. | en_US |
| dc.identifier.uri | http://hdl.handle.net/1903/11884 | |
| dc.subject.pqcontrolled | Environmental science | en_US |
| dc.subject.pquncontrolled | Mercury biogeochemistry | en_US |
| dc.subject.pquncontrolled | Surface - atmosphere exchange | en_US |
| dc.title | FACTORS INFLUENCING SURFACE ATMOSPHERE EXCHANGE OF GASEOUS ELEMENTAL MERCURY IN WESTERN MARYLAND | en_US |
| dc.type | Dissertation | en_US |
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