Bacterial Communities on the Northern Gulf of Mexico Continental Shelf are Influenced by Sediment Characteristics Affected by the Mississippi River

Benthic bacteria in the Gulf of Mexico serve the base of the sediment food chain as a food source for various marine organisms. In this paper, we analyzed the bacterial community and sediment characteristics from 14 sediment samples collected along the continental shelf of the northern Gulf of Mexico. Using the bacterial community to assess relationships among our sites, the data revealed groupings of sites that correlated to the sediment characteristics, generally grouped as western sites in Louisiana near the outflow of the Mississippi River and eastern Florida sites more distant from the outflow. Cluster analysis and multidimensional scaling demonstrated significant groupings of Louisiana vs Florida bacterial communities, and distance-based redundancy analysis related these groupings to sediment characteristics. Given the directions of currents around the Mississippi River, our data suggested that the outflow of the river is a major factor affecting the benthic bacterial community in the northern Gulf of Mexico