Comparison of SOC Composition Using FTIR for Shelterbelts and Agricultural Fields in Saskatchewan.

Land use and management practices influence the soil organic carbon (SOC) content as well as its composition. Plant litter is the primary organic input in tree-dominated systems such as shelterbelts, as opposed to decomposition of roots in agricultural fields. Hence, the establishment of shelterbelts on agricultural land is expected to affect the SOC composition and its decomposition rate, since it is intimately linked with the quality of plant input. The objective of this study was to determine the concentration and composition of SOC under the major hardwood and conifer shelterbelts and the adjoining agricultural fields across the soil zones of Saskatchewan using the Fourier Transform Infrared Spectroscopy (FTIR) technique. Preliminary results suggest that the combination of ATR-FTIR spectroscopy and chemometric techniques such as partial least squares (PLS) can be effectively used for the prediction of concentration of SOC under the shelterbelts and agricultural fields. Further, the composition of SOC is only different between species of white spruce (Picea glauca), Scots pine (Pinus sylvestris) and caragana (Caragana arborescens) and not between the shelterbelts and agricultural fields. Further results are expected to provide information on the effect of age and management practices of the shelterbelts on the composition of SOC and the role of specific functional groups to the recalcitrance of SOC under the shelterbelts and the agricultural fields. ATR-FTIR is a simple and effective technique for the prediction of SOC concentration and composition underneath the shelterbelts and agricultural fields and can be effectively used in the carbon sequestration studies.