NSF -Marsh Photosynthesis and Oil Impacts

Impact and recovery of photosynthesis in the salt mash species Spartina alterniflora 

along the northern Gulf Coast after the 2010 oil spill

Patrick Biber and Wei Wu

This study looked at the ability of the salt-marsh species, Spartina alterniflora (Smooth Cordgrass), to recover from oil impacts. Our research occurred primarily at a site on Marsh Point, Jackson Co., MS (30 22' 28.0"N; -88 47' 19.5"W), near to the Gulf Coast Research Lab (GCRL). This study was funded in part by an NSF grant #DEB-1048342 "Quantifying the potential impacts of the BP Deepwater Horizon oil spill on carbon services of salt marshes along the Northern Gulf Coast".

Oil was first observed at this location on July 9, 2010 (http://www.usm.edu/gcrl/ss/reports/ss.070910.php) just after the passage of Tropical Depression No. 2. Scientists were able to access the site and monitor the effects of the oil on Spartina plants on July 21, 2010 when 12 days had passed.

We used a control-impact assessment approach, with 2 control sites, 2 medium oiled, and 2 heavy oiled sites. At each site we used a Walz Mini-pulse amplitude modulated (PAM) fluorescence meter to interpret the impacts to photosynthesis (actually the light reaction) of the oil. Ten randomly selected individuals were measured for light and dark-adapted yield. Measurements were standardized to the middle location of the first fully mature leaf since previously collected data showed that photosynthesis of different leaves and different locations along a leaf are significantly different from each other. Subsequent sampling was undertaken every 60-90 days for a full year to document recovery from acute stress, but also to capture potential chronic effects.

Linked pages for this project:

Time Series Photos - NSF - Photos 

Results - NSF - Results 

More Information - NSF - More Information