New research helps fight N2O emissions
Nitrous oxide (N2O) is the third most important greenhouse gas, next to CO2 and methane and is a serious destructor of the stratospheric ozone layer. Microorganisms are responsible for most N2O emissions through nitrification and denitrification. A better understanding of the ecology and physiology of these organisms holds a key to reducing the release of harmful N2O from agriculture and waste treatment. The EU-funded project NORA (Nitrous oxide research alliance training network) has identified factors that affect the amounts of N2O produced and propose solutions. The NORA team – nine academic partners and five industrial partners – is highly interdisciplinary and worked at cell level to field scale investigations. These included detailed biochemical, microbiological and physiological analysis on relevant microorganisms, mathematical modelling to understand the regulatory biology of denitrification, studies on regulatory responses of isolated key strains, and analyses of how microbial community composition and land management relate to N2O emissions, and how this is affected by different environmental factors. New regulatory mechanisms related to bacteria and N2O were discovered as well as enhanced understanding of specific organisms and bacteria that act as sinks for N2O. Findings also show that N2O emissions can be reduced by increasing the pH of acidic soils, by providing enough copper to soils and by using slow-release fertilisers, and that waste treatment plants may harbour organisms that can significantly reduce the release of N2O. In addition, the project developed a new field robot to measure N2O emissions, enabling effective monitoring of field experiments. NORA has encouraged the emergence of a new generation of nitrogen researchers. It organised 5 summer schools on relevant topics and helped recruited nine early stage researchers and three fellows. In addition, it organised two workshops on mathematical modelling and on gas flux measurements in terrestrial ecosystems, and the 21st European Nitrogen Cycle meeting including an open public lecture. The results, which were disseminated through science journals, magazines, articles and television, provide valuable insight regarding fertilisers and soil management for reducing N2O emissions. This will no doubt guide policymakers on managing N2O and will certainly benefit the fight against global warming.
Keywords
N2O emissions, nitrous oxide, global warming, waste treatment, NORA, greenhouse gases
