Date of Award


Degree Type


Degree Name


Degree Program

Biological Sciences


Biological Sciences

Major Professor

Utley, John; Hester, Mark

Second Advisor

Poirrer, Mike

Third Advisor

Reed, Denise


Aboveground plant community dynamics in the oligohaline marsh at Big Branch Marsh National Wildlife Refuge, Louisiana, USA, were assessed in response to nutrient loading (3 N x 3 P treatments) and disturbance (both planned lethal disturbance and stochastic tropical storm/hurricane disturbance). Sampling was conducted seasonally from April 2004 to September 2006. Spartina patens and Schoenoplectus americanus are co-dominant plant species in this marsh. Low N-loading additions resulted in increased S. patens cover. However, increased N loading did not result in a shift in plant community composition despite S. americanus consistently having higher leaf tissue N than S. patens. Our results indicate that S. americanus may be more resilient than S. patens to disturbances that do not increase marsh surface elevation. Hurricane Katrina deposited significant amounts of sediment into remaining plots (August 29, 2005). By 2006, this disturbance resulted in a significant increase in both species richness and S. patens cover.


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