A comparison between the walkley‐black and a dry combustion method for determining organic carbon in a humic brown soil, Papua New Guinea

Abstract

Abstract Regression equations for the relationship between Walkley‐Black carbon and carbon by dry combustion in a tropical humic brown clay soil were variable in four different vegetation regimes. In one case, statistically different correlation coefficients were obtained for grassland surface and the corresponding subsurface soils. Calibration of the Walkley‐Black method against dry combustion carbon is recommended for each treatment in soil fertility studies as soil organic matter might have a different composition and hence carbon recovery value because of treatment.