A research published in the Elsevier Journal focused on the impact of the oil spill on the salt marsh habitats along the southeastern Louisiana coast. Satellite and ground data were used to assess two of the most important marsh biophysical characteristics, distribution of canopy chlorophyll content and above ground green biomass. Both were monitored during the salt marsh growing season (May–October) of 2009 (pre-spill) and 2010 (post-spill). This research provided scientists the ability to compare and isolate the spill impacted areas (Mishra et.al 2012).
Field data collection (ground data) was one of the methods used to assess the damages of the spill. Sixty nine salt marsh plots across an oil gradient ranging from heavy, moderate, light and no oil were sampled in southeastern Louisiana during the post spill growing season and used for model calibration. A separate dataset of twenty six plots from a different geographic location were sampled at a different time of the year to provide model validation. During data collection, numerous areas of oil blanketing, marsh browning, oil infiltration of root systems and damage due to clean up efforts were observed. (Mishra et.al 2012)
The initial assessment of all data collected showed that there was a significant post-spill increase in areas with reduced biomass and canopy chlorophyll (> 400 km2) during the 2010 growing season when compared to just 50–65 km2 during the 2009 growing season. Phenological analysis of the post oil-spill data revealed a significant decrease in the magnitude of biomass and canopy chlorophyll during the peak of the 2010 growing season. June was consistently found to be the worst month in terms of salt marsh health across Louisiana over the 2010 phenological cycle followed by the initial signs of recovery along the fringing marsh areas proximal to the shoreline that were first impacted by oil. Interior marsh patches exhibited persistent signs of stress towards the end of the growing season with extensive reduction in photosynthetic activity during the peak of the growing season (Mishra et.al 2012).
Another method used to assess the impact of the biggest oil spill in history is the use of the Advanced Visible Infrared Imaging Spectrometer (AVIRIS). Data was obtained from flights over Barataria Bay, Louisiana in September 2010 and August 2011. The oil contamination was mapped using oil absorption features in pixel spectra and was used to examine the impact of oil along the oiled shorelines.
The results showed that vegetation stress was present in the tidal zone and extended 14 miles inland from the shoreline in September 2010. Four indices of plant stress and three indices of canopy water content all consistently showed that the stress levels were highest in pixels next to the shoreline and decreased further inland. Index values along the oiled shoreline were significantly lower than those along the oil-free shoreline. Regression of index values with respect to distance...