Further results on comparison of methods for quantifying soil carbon in tropical peats

•We propose an alternative formula for predicting carbon density in tropical peats.•Carbon density is predicted from an average carbon content (0.55 ± 0.02 g g− 1) multiplied by measured bulk density.•The formula is valid for carbon content greater than 0.5 g g− 1 regardless of land use.•If bulk density > 0.25 g cm− 3, carbon content should be measured.

We present an alternative equation for estimating carbon density of tropical peatlands. We compiled a dataset of tropical peatlands with various land uses and found that when carbon content is greater than 0.5 g g− 1, there is no relationship between carbon content and bulk density. Thus, carbon density can be estimated from an average carbon content (0.5501 ± 0.0225 g g− 1) multiplied by the measured bulk density. This simple model is in contrast with previous studies, where a linear regression model is fitted to the carbon density and bulk density data. We tested the model to the data and demonstrated its high accuracy and applicability across land uses.