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Submitted to: Microbial Ecology International Symposium
Publication Type: Abstract Only Publication Acceptance Date: 5/2/2010 Publication Date: 8/22/2010 Citation: Miller, D.N. 2010. Nitrification and Denitrification Communities Associated with a Semi-Permeable Swine Waste Lagoon Biocover. Microbial Ecology International Symposium. 2010 CDROM. Paper No. PS.06.062. Available: http://www.isme-microbes.org/sites/isme-microbes.org/files/ALL_POSTERS_TOPIC_ORDER.pdf Interpretive Summary: Ammonia emission from swine waste lagoons presents a serious environmental challenge to pork producers. Semi-permeable swine waste lagoon biocovers have been developed to serve as a physical barrier and as a site for beneficial microbes to grow, but microbial analysis of these attached (biofilm) communities is needed. Samples of mature biocover and its associated biofilm and lagoon liquids were collected from a swine waste lagoons, and their potential nitrifying and denitrifying activities were determined in laboratory aerobic and anaerobic incubations. Potential nitrification and denitrifying activities were measured in biocover samples having mature biofilms, but little to no nitrifying and denitrifying activities were observed in new biocover (no biofilm) and lagoon wastewater samples. Molecular analyses of PCR products by DGGE were consistent with the activity assays and indicated that bacterial nitrifiers were present. We conclude that the biocover served as a useful support for the production of a beneficial biofilm community capable of transforming NH3 to N2 via a coupled nitrifying and denitrifying process. Technical Abstract: Ammonia emission from swine waste lagoons presents a serious environmental challenge to pork producers. Semi-permeable swine waste lagoon biocovers have been developed to serve as a physical barrier and as an attachment site for biofilm development, but microbial analysis of the biocover technology is needed to validate their usefulness. Samples of mature biocover and its associated biofilm and lagoon liquids were collected from a swine waste lagoons, and their potential nitrifying and denitrifying activities were determined in laboratory aerobic and anaerobic incubations. Potential nitrification activity for the mature biocover samples produced 1.9 µmoles NO2- L-1 hr-1 during a 24-hour period, whereas new biocover (no biofilm) and lagoon supernatant samples produced < 0.008 µmoles NO2- L-1 hr-1. Potential denitrifying activity for the mature biocover samples consumed 25 µmoles NOx- (NO3-+ NO2-) L-1 hr-1. In the supernatant and new biocover (no biofilm) samples < 1.6 µmoles NOx- L-1 hr-1. Molecular analyses of PCR products by DGGE indicate that Betaproteobacterial nitrifiers are present. We conclude that the biocover served as a useful support for the production of a beneficial biofilm community capable of transforming NH3 to N2 via a coupled nitrifying and denitrifying process. |
