Nitrogen Cycle in Natural and Engineered Ecosystems -- an Ecogenomics Perspective
Ramesh Goel
Civil & Environmental Engineering, University of Utah
ABSTRACT:Managing the nitrogen cycle is regarded as one of the 14 grand challenges in the 21st century by National Academy of Engineering. Intense agricultural activities to meet the growing food market as well as point and non point pollution in urban areas have disrupted the global nitrogen cycle. Increased inorganic nitrogen loading in municipal wastewater leads to eutrophication of receiving water bodies. As a result, liquid waste streams containing nitrogen require treatment for nitrogen removal. Energy and carbon intensive nitrification and denitrification bio-processes are generally employed to manage nitrogen in liquid waste streams. New additions such as ANaerobic AMMonium OXidation (ANAMMOX) have provided innovative and energy efficient nitrogen removal alternatives to wastewater treatment plant managers to manage nitrogen in liquid waste streams. More advances include anoxic methane oxidation coupled denitrification of nitrite and nitrate by unique organisms. We have been studying these unique nitrogen transforming processes in ecosystems and have been applying the knowledge gained from ecosystem-level studies to develop wastewater treatment technologies. The ecology of the main players, i.e, prokaryotes, is being studied using whole community metagenomics and metatranscriptomics. This presentation will include an overview of recent advances in nitrogen cycle and will detail some of the findings in Dr. Goel’s lab related to the application of anammox for real centrate (digester reject water) treatment, coupling of anammox with autotrophic denitrification and, enrichment of anoxic methane oxidizing bacteria. The results of a study on the effect of external perturbations (e.g. toxic chemicals and temperature) on single stage partial nitrification-anammox reactors will also be presented.
