Nutrient Management of Nursery Runoff Water using Constructed Wetland Systems

 

Situation: Discharge from nurseries and greenhouses can carry high concentrations of nitrogen (N) and phosphorus (P) to surrounding surface waters. These excess nutrients can degrade aquatic ecosystems and cause eutrophication. Vegetated surface-flow constructed wetlands hold promise to remove nutrients from runoff before it reaches nearby water resources.

 

Actions: Researchers from Clemson University, in partnership with Monrovia® Growers, investigated the efficacy of an established vegetated surface-flow constructed wetland to remove N and P from runoff water from a commercial nursery. The study was conducted over a 38-month period. 

 

Take-home message: 

• Nitrate-N removal efficiency averaged 94.7% from March through November.
• From December to February, the mean wetland water temperature dropped below 15⁰ C, and N removal efficiency declined to 70.7%.
• Orthophosphate-P removal efficiency was widely varied and did not correlate with water temperature.
• During peak growing season, constructed wetlands can be highly efficient at removing N from runoff.

 

For more information:

• Taylor, M.D., S.A. White, S.L. Chandler, S.J. Klaine, and T. Whitwell. 2006. Nutrient management of nursery runoff water using constructed wetland systems. Hortechnology 16: 610-614.
• White, S.A., M.D. Taylor, S.L. Chandler, T. Whitwell, and S.J. Klaine. 2010. Remediation of nitrogen and phosphorus from nursery runoff during the spring via free water surface constructed wetlands. Journal of Environmental Horticulture. 28(4):209-217.
• Email Sarah White at swhite4@clemson.edu