Salt Marsh Sediment Biogeochemical Response to the BP Deepwater Horizon blowout (Skiff Island, LA, and Cat Island, Marsh Point and Saltpan Island, MS)

Author

Calista Lee Guthrie

Issuing Body

Mississippi State University

Advisor

McNeal, Karen S.

Committee Member

Kirkland, Brenda

Committee Member

Schmitz, Darrel

Committee Member

Mishra, Deepak

Date of Degree

5-11-2013

Document Type

Graduate Thesis - Open Access

Major

Geosciences

Degree Name

Master of Science

College

College of Arts and Sciences

Department

Department of Geosciences

Abstract

The impact of the Deepwater Horizon blowout on coastal wetlands can be understood through investigating carbon loading and microbial activity in salt marsh sediments. Carbon influx causes pore water sulfide to increase in wetland sediment, making it toxic and inhospitable to marsh vegetation. High sulfide levels due to increased microbial activity can lead to plant browning and mortality. Preliminary analyses at Marsh Point, Mississippi indicated that sulfate reducing bacteria are more active in contaminated marsh, producing sulfide concentrations 100x higher than in noncontaminated marsh. Sediment electrode profiles, hydrocarbon contamination, and microbial community profiles were measured at three additional locations to capture the spatial sedimentary geochemical processes impacting salt marsh dieback. Findings indicate that response to contamination is variable due to physical and biogeochemical processes specific to each marsh. Temporal evaluation indicates that there is a lag in maximum response to contamination due to seasonal effects on microbial activity.

URI

https://hdl.handle.net/11668/16580

Comments

sulfide||biogeochemistry||salt marsh

Recommended Citation

Guthrie, Calista Lee, "Salt Marsh Sediment Biogeochemical Response to the BP Deepwater Horizon blowout (Skiff Island, LA, and Cat Island, Marsh Point and Saltpan Island, MS)" (2013). Theses and Dissertations. 3853.
https://scholarsjunction.msstate.edu/td/3853