A VOLUMETRIC INORGANIC CARBON ANALYSIS SYSTEM

Measurement of soil organic carbon (OC) is slow and expensive when ino rganic carbon (TC) is present. Our objective was to develop an automat ed volumetric IC analysis system, thus allowing OC to be determined by difference, The system was developed by combining a pressure transduc er with a personal computer (PC), data acquisition board, and appropri ately developed software. The volumetric system was compared with comb ustion, neutralization, and sum of Ca + Mg techniques for samples cont aining up to 60 g kg(-1) IC, Correlations between methods showed linea r agreement (r(2) greater than or equal to 0.994). The volumetric syst em was more precise for relatively low IC amounts (2.0 g kg(-1)) and c ould process 20 samples h(-1).