** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** AN ACTIONABLE UNDERSTANDING OF NUTRIENT LOAD AND BIOAVAILABILITY TO CYANOBACTERIA IN FRESHWATER SYSTEMS IS FUNDAMENTAL TO MANAGING WATER QUALITY AND MITIGATING HARMFUL ALGAL BLOOMS (HABS), ESPECIALLY UNDER GLOBAL WARMING PRESSURES. HOWEVER, THE DECADES-LONG PRACTICES FOR WATER QUALITY ANALYSES BY USDA, AS WELL AS FEDERAL AND STATE REGULATORY AGENCIES (E.G., USEPA), DEPEND HEAVILY ON THE CUTOFF THAT SEPARATES NUTRIENT FLUXES BETWEEN PARTICLES AND THE DISSOLVED PHASE USING A NOMINAL 450-NM PORE-SIZE FILTER MEMBRANE. THE OBTAINED DISSOLVED PHASE (I.E., <450 NM) INCLUDES SMALL COLLOIDS (<450-100 NM), NANOPARTICLES (<100-1 NM), AND THE TRULY DISSOLVED PHASE (<1 NM), WHICH SIGNIFICANTLY OVERESTIMATES NUTRIENT LOAD IN THE TRULY DISSOLVED PHASE. THE LONG-TERM INACCURATE KNOWLEDGE OF NUTRIENT LOAD AND BIOAVAILABILITY IN DIFFERENT SIZE FRACTIONS PRECLUDES US FROM FORMULATING EFFECTIVE PLANS FOR NUTRIENT MANAGEMENT AND WATER QUALITY RESTORATION. THE GOAL OF THE PROPOSED PROJECT IS TO ACCURATELY REEVALUATE THE 'REAL CONTRIBUTION' OF DIFFERENT SIZE FRACTIONS ON NUTRIENT LOAD AND BIOAVAILABILITY TO CYANOBACTERIA IN ECONOMICALLY IMPORTANT CATFISH AQUACULTURE PONDS IN ALABAMA UNDER A WARMER CLIMATE. THE FINDINGS OBTAINED FROM THE PROPOSED PROJECT WILL ENABLE USDA, REGULATORY AND STATE AGENCIES, CATFISH PRODUCERS, AND OTHER AQUACULTURE STAKEHOLDERS TO IMPROVE CURRENT BEST MANAGEMENT PRACTICES (BMPS) FOR THE FORECASTING AND MITIGATION OF CYANOBACTERIAL HABS USING COST-EFFECTIVE ENGINEERED SOLUTIONS (E.G., ENGINEERED BIOCHARS), CONTRIBUTING TOWARDS MORE SUSTAINABLE AQUACULTURAL PRODUCTIVITY AND PROFITABILITY IN A WARMER CLIMATE.

Auburn University, Auburn AL

Investigators