The 2012 ASHS Annual Conference

Objective(s):
1. To increase awareness of regulations and rationale for limiting nutrient release into surface waters. 2. To discuss impacts of regulations on grower (nursery and orchard) management practices and economic viability. 3. To present technologies growers can apply to help meet these stringent water quality criteria.

In recent years, scientists have gained a better understanding of the impact of nutrient enrichment on ecological systems.  With enhanced knowledge of the potentially detrimental impacts of eutrophication on our ecological resources, environmental groups and the public began to demand greater protection and restoration of these resources.  Regulations have been enacted in various regions throughout the United States to limit nutrient loading, with the ultimate goal of improving surface water quality and restoring ecological function (fisheries, native plant communities, etc.).  This colloquium will focus on 1) three current water quality regulations and the rationale for limiting nutrient release into surface waters, 2) horticultural production management and the economic impacts current regulations have on growers in FL, and 3) proven technologies that growers can apply to help meet these stringent water quality criteria.  Presenters for the first topic will discuss the TMDLs (Total Maximum Daily Loads) enacted in the Chesapeake Bay Watershed in 2010, with specific focus on collaborative efforts of growers, researchers, and regulators in Maryland to derive meaningful loading rate estimates to facilitate better predictions of potential nutrient load reductions via changed horticultural production practices; the Numeric Nutrient Criterion enacted in Florida in 2009 focusing on the costs of unchecked nutrient enrichment of surface waters from an environmentalist perspective; and a water quality mandate in CA, with specific emphasis on current sampling protocols for determination of compliance with water quality limits and the potential for improving accuracy in current nutrient loading estimation techniques.  Two case studies, presented by a Florida nursery grower and citrus producer, will discuss the impacts of the numeric nutrient criterion on changes in production, irrigation, and runoff handling practices and economic viability.  We will close by presenting technologies that a variety of horticultural producers can apply to better manage and treat runoff so that impacts on environmental health and surface waters are abated.