Recently, the nitrous oxide isotope monitoring system of Shenyang Institute of Applied Ecology, Chinese Academy of Sciences, has passed the acceptance inspection. The system is mainly used to measure the nitrous oxide concentration and isotope values of outdoor environmental gases and collect samples. The system consists of Aerodyne high time resolution trace gas and isotope analyzer and gas multi sampler. This system is capable of real-time, fast, accurate, and online continuous measurement of nitrous oxide gas and isotope concentration in the ambient atmosphere, and can also be conveniently used for measuring gas isotopes in samples. The measurement principle is based on tunable mid infrared laser direct absorption spectroscopy technology, with a sampling frequency of up to 10 Hz.

Quantifying the sources and sinks of nitrous oxide is one of the urgent issues to be addressed in the field of global climate change. There are multiple pathways for the production of nitrous oxide in soil, but the relative importance of these pathways and their correlation with soil factors are currently unclear. Therefore, quantifying the process rate and distinguishing their contributions is necessary to further reveal the response of nitrogen cycling to global change and its biological mechanisms. In recent years, with the rapid development of isotope determination technology, a new method for determining the positional advantage value SP of 15N between N2O molecules has gradually gained attention. This method has the advantages of not requiring the addition of substrates to the soil, not being affected by the isotopic values of substrates produced by N2O, and having significantly different SP values for different N2O production processes.

Aerodyne's nitrous oxide isotope monitoring system is mainly used to determine the concentration of nitrous oxide and the nitrogen oxygen isotope ratio in the environment. It can achieve a new method of distinguishing the process of N2O production using the positional advantage value SP of 15N. Therefore, it can be applied to both indoor analysis of sample collection and real-time monitoring of outdoor environments. The gas injector of the system can meet the analysis requirements of nitrogen and oxygen isotopes for N2O small volume samples (10 mL) during the experimental process. The entire experiment is controlled by a program, with fast experimental speed and batch processing. The program can be modified and customized according to the needs of the experiment, which is free and flexible, meeting the needs of customers.

The system adopts a 210 meter optical cavity, which effectively improves the sensitivity and accuracy of the measurement.

The system is equipped with Igor Pro professional software, which provides literature level data processing and analysis. The software has multiple functions such as data download, error analysis, leakage analysis, curve analysis, and data transfer.

System measurementN₂OGas andisotopeHaving a very highAccuracy:

The measured results meet the measurement standards: