Phytoplankton dynamics in Louisiana estuaries: Building a baseline to understand current and future change

Louisiana estuaries are important habitats in the northern Gulf of Mexico, a region undergoing significant and sustained human-and climate-driven changes. This paper synthesizes data collected over multiple years from four Louisiana estuaries - Breton Sound, Terrebonne Bay, the Atchafalaya River Delta Estuary, and Vermilion Bay - to characterize trends in phytoplankton biomass, community composition, and the environmental factors influencing them. Results highlight similarities in timing and composition of maximum chlorophyll, with salinity variability often explaining biomass trends. Distinct drivers for biomass versus community structure were observed in all four estuarine systems. Systems shared a lack of significant correlation between river discharge and overall phytoplankton biomass, while discharge was important for understanding community composition. Temperature was a significant explanatory variable for both biomass and community composition in only one system. These results provide a regional view of phytoplankton dynamics in Louisiana estuaries critical to understanding and predicting the effects of ongoing change.

Automated summary

This paper synthesizes data from four Louisiana estuaries to characterize trends in phytoplankton biomass, community composition, and the environmental factors influencing them. Results show that salinity variability often explains biomass trends, while temperature is a significant explanatory variable for only one system. Understanding these dynamics is critical for predicting the effects of ongoing change.