See more from this Session: Managing Nutrients In Organic Materials and by-Products: II
Wednesday, October 19, 2011
Henry Gonzalez Convention Center, Hall C, Street Level
Compost teas (CT) are liquid extracts made from soaking compost in water. Production methods are as of yet not well defined. This study focused on how brewing time affects dissolved constituents in CT. A mixture of 1 kg compost (Busy Bee Gardens, LLC. Mosinee, WI) to 10 L de-chlorinated water was used. Teas were brewed in triplicate by actively aerating the compost-water solution for 5 days. Samples were taken immediately and every 12 hours after the compost was introduced to water. Samples were filtered and analyzed for nitrate (NO3-), ammonium (NH4+), dissolved organic carbon (DOC), soluble reactive phosphorus (SRP), potassium (K+), pH, and electrical conductivity (EC). DOC, SRP, K+, pH and, EC increased rapidly in the first 12 hours then increased steadily until experiment termination. NH4+ decreased initially over the first 24 hours (0.107 ± 0.133 ppm NH4+ to 0.0386 ± 0.0095 ppm NH4+) then fluctuated (0.0728 ± 0.0342 ppm NH4+) for the duration of the experiment. NO3- increased steadily during the first 12 hours (17.00 ± 1.47 ppm NO3- to 19.83 ± 0.25 ppm NO3-) then increased only slightly until experiment termination (19.83 ± 0.25 ppm NO3- to 20.77 ± 0.093 ppm NO3-). Future experiments will investigate compost source variability in constituent release. Preliminary results may be discussed.