March 03, 2016
A recent study led by Dr. Kai Ziervogel and involving several other ECOGIG researchers- Dr. Samantha Joye, Dr. Nigel D'souza, Dr. Joseph Montoya, Dr. Uta Passow and Dr. Carol Arnosti- investigated the after effects of Hurricane Isaac on phytoplankton concentrations in the Mississippi River Delta.
Runoff from rivers often triggers microbial responses in coastal marine environments, including phytoplankton blooms, that drive the transformation of organic matter on its way from land to the deep ocean. Dr. Ziervogel's team measured organic matter, bacterial community abundance and activities in the water column at three sites near the Mississippi River Delta about 2 weeks after Hurricane Isaac made landfall in 2012. They found the river plumes had elevated salinity and dissolved organic carbon due to the storm surge that pushed large amounts of marine waters upstream. They also found high concentrations of phytoplankton particulate matter and low levels of microbial particles that suggested storm-induced river discharge triggered the development of phytoplankton blooms that were in their intitial stages at the time of sampling.