[M-IS03] Exploring the role of soil in earth science: ecological/biogeochemical linkage and beyond

[MIS03-P01] Applications of Cavity Ring-Down Spectroscopy to carbon, nitrogen and water cycling in soil

*Kate DENNIS¹, Kuan HUANG¹ (1.Picarro, Inc.)

Keywords:CRDS, soil flux, nitrogen isotopes, evapotranspiration

Over the past five years, advances in cavity-enhanced absorption spectroscopy have fundamentally changed the way soil scientists study carbon, nitrogen and water cycling between the subsurface, plants and the atmosphere. With the continuous evolution of performance, including high precision, low drift and part-per-billion resolution, along with compact, field-deployable and easy-to-use instruments, scientists are increasingly able to leave their labs and make measurements directly in the field. Here we describe how Picarro's Cavity Ring-Down Spectroscopy technology has been applied to a number of soil applications, including (i) the determination of soil flux measurements by coupling newly developed real-time software with simultaneous measurements of CO₂, CH₄, N₂O, NH₃ and H₂O from closed-loop, recirculated soil chambers; (ii) partitioning water loss from evaporation versus transpiration in arid environments using in-situ measurements of ambient atmospheric water vapor measurements, soil water isotopes and the isotopic signature of local transpiration; and (iii) using in-situ measurements of d¹⁵N and the site preference of ¹⁵N in N₂O to constrain N₂O emissions in agricultural settings.