PARENT SESSION
Poster Session #2: Carbon Storage.
Monday, August 5. Presentation from 5:00 PM to 6:30 PM. Exhibit Hall B & C, TCC

Advances in soil carbon measurement for ecosystems: laser-induced breakdown spectroscopy (LIBS).

Meyer, Clifton^*,1, Ebinger, Michael¹, Cremers, David², Ferris, Monty², Breshears, David¹, Unkefer, Pat³, ¹ Environmental Dynamics and Spatial Analysis Group, Los Alamos, NM² Chemistry and Advanced Diagnostics, Los Alamos, NM³ Biosciences Division, Los Alamos, NM

ABSTRACT- Accurate measurement of carbon in soils remains one of the largest challenges in understanding sources and sinks of carbon in terrestrial systems. Conventional methods of analyzing carbon require large initial volumes of soil, therefore obtaining samples for conventional analysis is time consuming and expensive. The application of laser -induced breakdown spectroscopy (LIBS) to carbon analysis has several advantages over conventional methods, such as rapid measurement of samples and improved accuracy of the measurements, and it requires only a small soil sample for a measurement. Recently, LIBS instrumentation has been modified for soil carbon measurement in the field. With this advance, the rapid and accurate LIBS method can be used on small samples obtained from soil pits, or intact soil cores can be scanned and carbon concentration information can be obtained from depth intervals less than 1 cm. Preliminary results from a field-portable LIBS instrument show the variability of soil carbon with depth from soil cores. We also illustrate the application of hundreds of LIBS measurements to estimate soil carbon inventories. These two results show the potential of LIBS analysis in measuring carbon in soils and suggest that new information with reduced uncertainty can be obtained using LIBS analysis in the field.

KEY WORDS: LIBS, soil, measurement, carbon