Design and construction of a reduced temperature testing apparatus for denitrification

Excess nitrogen in aquatic systems contributes to significant water quality degradation. Agricultural runoff during springtime snowmelt and rainfall events transports large quantities of nitrogen from agricultural fields into aquatic systems. Previous laboratory experiments to evaluate denitrification under reduced temperature scenarios are often limited to enclosed columns in small freezer spaces. This large-scale laboratory experiment uses individual housing units (chambers) to contain surface exposed bins (troughs), which house media, soil, and plants. This apparatus is designed for indoor application to test for denitrification under reduced temperature scenarios. Each chamber is equipped to simulate tile drainage flow under springtime air and water temperatures found in the Upper Midwest, USA.