Event Title

Promoting Scenedemus sp. Survival Against Zooplankton with Unionized Ammonia

Location

Old Dominion University, Learning Commons at Perry Library, West Foyer

Start Date

8-4-2017 8:30 AM

End Date

8-4-2017 10:00 AM

Description

An experiment was conducted to limit Scenedesmus sp. grazers, as predation reduces biofuel yields. For the first treatment, 2.5 L cultures of Scenedesmus sp. with zooplankton present were inoculated in photobioreactors with 640 mg/L urea. A second treatment employed a 500 mg/L spike of NH4Cl on day zero. The third treatment used 750 mg/L NH4Cl without urea. Cell counts were performed with a hemocytometer and Gridded Sedgewick Rafter (1 mm2) and ammonia was measured using ion chromatography. Urea was observed to impact zooplankton by day eight, with a 24-48 hour lag time after accumulating free ammonia which was confirmed by the NH4Cl spike. Cultures with 750 mg/L NH4Cl (added in 250 mg/L increments on days zero, one and two) were ultimately adjusted to pH 8.6 in week two. This theoretically increased the free ammonia concertation sufficiently to potentially impact zooplankton by day eleven.

Presentation Type

Poster

This document is currently not available here.

Share

COinS
 
Apr 8th, 8:30 AM Apr 8th, 10:00 AM

Promoting Scenedemus sp. Survival Against Zooplankton with Unionized Ammonia

Old Dominion University, Learning Commons at Perry Library, West Foyer

An experiment was conducted to limit Scenedesmus sp. grazers, as predation reduces biofuel yields. For the first treatment, 2.5 L cultures of Scenedesmus sp. with zooplankton present were inoculated in photobioreactors with 640 mg/L urea. A second treatment employed a 500 mg/L spike of NH4Cl on day zero. The third treatment used 750 mg/L NH4Cl without urea. Cell counts were performed with a hemocytometer and Gridded Sedgewick Rafter (1 mm2) and ammonia was measured using ion chromatography. Urea was observed to impact zooplankton by day eight, with a 24-48 hour lag time after accumulating free ammonia which was confirmed by the NH4Cl spike. Cultures with 750 mg/L NH4Cl (added in 250 mg/L increments on days zero, one and two) were ultimately adjusted to pH 8.6 in week two. This theoretically increased the free ammonia concertation sufficiently to potentially impact zooplankton by day eleven.