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An assessment framework for Tampa Bay Water's Hydrobiological Monitoring Program (HBMP) has been established based on the relationship between freshwater flow and primary environmental indicators monitored under the HBMP. The underlying paradigm is based on the understanding that reduced flows can result in water quality conditions adverse to biological populations if these conditions exceed a specific magnitude and/or are beyond a certain duration. HBMP water quality parameters identified as primary indicators include salinity (due to osmotic pressure controlling distribution of fish, benthos, and vegetation among other ecological effects), dissolved oxygen (due to the aerobic stress to fish and benthos that can occur due to depressed dissolved oxygen concentrations), and chlorophyll-a (due to excessive phytoplankton blooms that may increase biological oxygen demand and can result in depressed dissolved oxygen concentrations). These primary indicators were identified because they specifically relate to linkages in the HBMP conceptual model as well as State of Florida water quality standards and a great deal of effort has been allocated to understanding these relationships. To this end, special studies have been implemented to further scientific information related to the effects of flows and withdrawals on the magnitude, duration, and distribution of phytoplankton as one aspect of the larger HBMP assessment framework. In this paper, we provide a summary of recent special studies completed in the lower Alafia River, focused on in situ fluorometer chlorophyll-a measurement, interpretation, and predictive capability. We share lessons learned and our steps for moving forward in efforts to relate flow (and withdrawal-related effects) on phytoplankton in the lower Alafia River. [ABSTRACT FROM AUTHOR]

The central eastern Florida shelf edge is a highly dynamic area that supports an important yet vulnerable deep-sea coral reefs ecosystem, the Oculina Coral Habitat Area of Particular Concern. Rapid and large short-terms (days to weeks) changes of bottom temperature (up to 9 °C) and p CO 2 (up to 180 μatm) were observed at the shelfbreak during a two-month (May 13-July 10, 2017) deployment of a lander package. An analysis suggests that these changes are the combined results of tides, the Gulf Stream meandering, and submesoscale eddies and filaments. The processes responsible for sub-tidal variability may include 1) the Gulf Stream frontal movements, 2) upwelling/downwelling of slope waters in association with the Gulf Stream variability, and 3) submesoscale processes and associated vertical movements. Satellite images also frequently show a narrow plume of elevated chlorophyll concentration that stretches from the coast northward up to >200 km along the Gulf Stream front during late spring and early summer. Our analysis indicates that these phytoplankton blooms in the plume are likely supported by the nutrient supply from the nutrients-rich slope waters to the shelf edge and subsequent local vertical mixing. Carbon export associated with these blooms can be an important food source to the Oculina corals. Upwelling of slope waters, on the other hand, will lead to increased CO 2 and reduced pH and aragonite saturation state along the shelf edge. Therefore, these dynamic processes may have strong impacts on the health and sustainability of the Oculina coral ecosystem. • Rapid short-terms changes of bottom temperature (up to 9 °C) and p CO 2 (up to 180 μatm). • A high chlorophyll plume stretches from the coast northward along the Gulf Stream front. • Short-terms variability are associated with GS meandering and submesoscale features. • The biogeochemical processes may have strong impacts on the deep coral ecosystem. [ABSTRACT FROM AUTHOR]