New Technology of Rapid Isotopic Measurement of Soil Organic Manner to Quantify Carbon Sequestration in Climate Change Studies

Understanding the stable isotopes of carbon and nitrogen (13C/12C-15N/14N) determine how the composition of organic matter will be changed by biogeochemical processes. Stable isotope data can contribute to both source-sink and process information in carbon- sequestration and climate change studies. In particular, there is a need to better understand the processes by which warming may drive increased plant productivity and atmospheric carbon uptake and storage in biomass and soils, as well as those processes that may drive an increase in the release of methane (CH4) and carbon dioxide (CO2) through microbial decomposition of soil carbon stored in the ecosystem. We propose the demonstration and evaluation of a new technology called LAMIS (Laser Ablation Molecular Isotopic Spectroscopy) which was developed by Applied Spectra in collaboration with the Lawrence Berkeley National Laboratory, to address the measurement of carbon and nitrogen isotopes. LAMIS provides isotope ratio measurements in real-time, at atmospheric pressure (no mass spectrometer) and without sample preparation. The technology is based on laser plasma spectroscopy. The traditional approach to chemical analysis using laser plasmas has been to measure atomic transitions which provide elemental analysis. This technology is known as LIBS (Laser Induced Breakdown Spectroscopy). LAMIS is different in that by tailoring these laser plasmas, we can enhance and measure molecular spectra. The benefit of molecular spectra is significantly enhanced isotopic signatures. Molecular spectra exhibit two- three orders of magnitude increase in isotopic splitting, which is easily measured at atmospheric pressure and with a relatively small spectrometer. Light elements are particularly favorable to LAMIS measurements. The proposed Phase I research will provide proof of principle of calculations and measurements for carbon and nitrogen isotopes, demonstration of LAMIS on known samples, and the proposed design of a Phase II prototype. The R & amp;D will be in collaboration with Oak Ridge National Laboratory.