Comparison of Two Methods for Estimating Carbon in the Soil.

Two methods of estimating total soil C content were compared for south Georgia soils. The first method utilized a Perkin-Elmer CHN analyzer. The second method was loss on ignition (LOI) using a muffle furnace. The LOI method has produced good correlation with the CHN analyzer in the Midwestern United States, and is quicker and less expensive to perform. Sixty soil samples from south Georgia were analyzed by both methods and the results compared to test the accuracy and reliability of LOI. Eight lake sediment samples were also used as controls, as previous studies have shown a good correlation between CHN analyzers and LOI for lake sediments. The lake sediments produced a good R² value of 0.982, which verifies that procedures and methods were performed correctly.  The soil samples produced a relatively low R² value of 0.44, which indicated a fairly poor relation between the two testing methods for the soils.  The low R² value of the soil samples determined in this research is likely due to the presence of iron oxides in the soil.