Spatial and temporal variation of microbial properties in the water column of Florida Bay

Physical and biological properties of the water column of Florida Bay were examined at seven study sites over an eighteen month period. The results indicated seasonality in some parameters, but was not evident in others. The data displayed statistically significant (P < 0.05) differences between study sites indicating spatial variation. The presence of seagrass affected the overlying water column, especially with respect to the biological parameters: those areas overlying seagrass beds displayed statistically significantly higher values than those over sparsely covered or barren areas. During the period of the study, Florida Bay experienced a seagrass die-off event: microbial activity and numbers were statistically significantly higher over areas of dying seagrass than over healthy or dead areas. The results of this study pointed to phosphorus being the controlling, or limiting factor, for microbial activity in the water column of Florida Bay.