RESPONSE OF A SPARTINA PATENS-DOMINATED OLIGOHALINE MARSH TO NITROGEN ENRICHMENT IN COASTAL NORTH CAROLINA, USA.

Coastal marshes are highly productive ecosystems that play a significant role in the global carbon budget. Anthropogenic alterations to coastal landscapes can significantly impact these marsh ecosystems, though the actual loss of ecosystem functioning may depend on the type of marsh being impacted. Nitrogen loading into coastal environments has accelerated with increased use of fertilizers for agricultural production. Previous work has demonstrated that some marsh plants respond to nitrogen inputs by allocating more biomass into aboveground stems and leaves while reducing belowground biomass. These changes could diminish the organic matter pool in coastal marshes while also making them more susceptible to erosion. The goal of this study was to fertilize plots in a Spartina patens-dominated oligohaline marsh with varying concentrations of urea applied throughout one growing season and assess the response in aboveground and belowground plant biomass and decomposition. Aboveground plant clippings and soil cores were collected to assess the changes in above- and belowground biomass among the treatments throughout time and to also assess tissue nitrogen and organic matter content. Litter bags were also placed at the soil surface of the experimental plots to determine rates of decomposition throughout the study. Neither aboveground nor belowground biomass was significantly affected by nitrogen application, and nitrogen assimilation into plant tissue did not vary across the treatments. Decomposition was also relatively similar across the treatments, though there were seasonal effects on litter mass loss. Our findings suggest that oligohaline marshes, specifically those dominated by S. patens, are not limited by nitrogen to the same extent as salt marshes.

Department dc:contributor.department

Biology

Grantor dc:publisher

East Carolina University

Year dc:date.issued

2013

Author dc:creator

• Wejrowski, Mark

Advisor dc:contributor.advisor

• Reyes, Enrique

• Ecology
• Biology
• Natural resource management
• Nitrogen
• Nutrient enrichment
• Wetland ecology
• Biology, Ecology

Handle dc:identifier.uri

http://hdl.handle.net/10342/4324

OAI identifier oai:identifier

oai:thescholarship.ecu.edu:10342/4324