Measuring Total Carbon for Carbon Sequestration
Climate change and the rise of CO² in the atmosphere has highlighted the possibilities of carbon sequestration in soil. Estimating sequestration possibilities involves accurately measuring Total Carbon (TC). TC is a measure of the organic and inorganic carbon contained within soil. TC in soil is a result of the decomposition of plant and animal matter, living and dead microorganisms, roots from plants, soil biota (which includes earthworms, nematodes, fungi, protozoa, bacteria, etc.) and carbon minerals.
TC affects soil characteristics, including color, nutrient capacity (cation and anion exchange capacity), nutrient stability and turnover, and subsequently water relationships, aeration, and cultivation. The accurate measurement of TC can result in better crop management for cultivated land and better understanding of available carbon pools in uncultivated land. VIS/NIR field spectroscopy offers a fast, accurate and affordable alternative to lab analysis of TC—an alternative that works without destroying the sample. Spectral Evolution’s NaturaSpec spectroradiometer is specifically designed for spectral analysis in situ. It’s rugged and reliable with a full range that covers wavelengths from 350 to 2500nm—UV/VIS/NIR.
In a typical soil spectra, TC spectral features would be seen at 400, 1000, 1400, 1900-2100 and 2200-2400nm. To determine TC it is important to have high resolution spectra for analysis. The spectra from TC measurements are automatically saved in ASCII format and can be further analyzed using multivariate statistical tools such as PLSR and chemometrics analysis and spectral libraries built for predictive modeling of soils.
Spectral Evolution’s NaturaSpec™ features high resolution and enhanced sensitivity to allow you to quickly collect clear spectra. Auto-shutter, auto-exposure, auto-dark current capabilities mean no manual optimization between scans. For soil analysis, the NaturaSpec can be equipped with a rugged and reliable sample contact probe, as well as a benchtop probe with sample compactor.
The NaturaSpec is ideal for soil analysis and mapping applications because it delivers: 
- Full spectral range of 350-2500nm
- 3 photodiode arrays
- No moving parts for greater reliability
- Automatic optimization of dark current and exposure with every scan
- User-replaceable, metal-clad fiber optic cable with SMA-905 input
- Lightweight and compact
All Spectral Evolution spectroradiometers come equipped with DARWin™ Data Acquisition software that collects data and saves it to a compatible ASCII format for use with 3rd party chemometric analysis software without requiring post-collection processing.
Our DARWin SP Data Acquisition software gives you complete control of your instrument interface, access to vegetation indices as well as the USGS sample library, and saves all spectra and metadata as ASCII files for use with 3rd party software. Optional EZ-ID™ sample identification software can help you match your target samples to the USGS, SpecMIN and GeoSPEC mineral spectral libraries to quickly identify clays. Or with the Custom Library Builder module, you can create your own soils and TC library by simply saving your metadata and scans.
NIR spectroscopy can be used in conjunction with complementary technologies, such as portable XRF where you can use the data from a NaturaSpec with the elemental analysis from XRF technology for a more complete picture of TC and other soil properties.