Low cost and state of the art methods to measure nitrous oxide emissions

This letter provides an overview of the available measurement techniques for nitrous oxide (N2O) measurement. It is presented to aid the choice of the most appropriate methods for different . Nitrous oxide is a very potent greenhouse gas; the effect of 1 kg of N2O is estimated to equivalent to 300 kg of CO2. Emissions of N2O from the soil have a larger uncertainty to other greenhouse gases. Important reasons for this are low atmospheric concentration and enormous spatial and temporal variability. Traditionally such small increases are by chambers and analyzed by gas chromatography. Spatial and temporal resolution is , but costs are low. To detect emissions at the field scale and high temporal resolution, at tens of ppt levels need to be resolved. Reliable instruments are now available to N2O by a range of micrometeorological methods, but at high financial cost. Although are effective in identifying processes and treatment effects and mitigation, the future lies the more versatile high frequency and high sensitivity sensors.