April 20, 2017 University of Georgia Full ScienceDaily Article Here
Increasing water temperatures are responsible for the accumulation of a chemical called nitrite in marine environments throughout the world, a symptom of broader changes in normal ocean biochemical pathways that could ultimately disrupt ocean food webs.
Nitrite is produced when microorganisms consume ammonium in waste products from fertilizers, treated sewage and animal waste. Too much nitrite can alter the kinds and amounts of single-celled plants living in marine environments, potentially affecting the animals that feed on them, said James Hollibaugh, co-author of the study published recently in Environmental Science and Technology. It also could lead to toxic algal blooms and create dead zones where no fish or animals can live.
“Typically, two groups of microorganisms work in really close concert with one another to convert ammonium to nitrate so that you don’t see nitrite really accumulate at all, but we found that the activity of those two groups was decoupled as a result of the increased water temperatures.”
…Nitrite accumulation can also result in more production of nitrous oxide, a powerful greenhouse gas that has more of an effect on climate change per molecule than carbon dioxide, Hollibaugh said. That nitrous oxide production then increases global temperatures more, causing more nitrite accumulation and creating a positive feedback loop.
Sylvia C. Schaefer, James T. Hollibaugh. Temperature Decouples Ammonium and Nitrite Oxidation in Coastal Waters. Environmental Science & Technology, 2017; 51 (6): 3157 DOI: 10.1021/acs.est.6b03483