Correction factors for dissolved organic carbon extracted from soil, measured using the Mn(III)-pyrophosphate colorimetric method adapted for a microplate reader

TitleCorrection factors for dissolved organic carbon extracted from soil, measured using the Mn(III)-pyrophosphate colorimetric method adapted for a microplate reader
Publication TypeJournal Article
Year of Publication2014
AuthorsGiasson, M-A, Averill, C, Finzi, AC
JournalSoil Biology and Biochemistry
Volume78
Pagination284 - 287
Date Published2014/11//
ISBN Number0038-0717
KeywordsColorimetric method, DOC, Forest soils, Mn(III)-pyrophosphate, Organic carbon
Abstract

Oxidizable dissolved organic carbon (DOC) is regularly measured in environmental samples using a colorimetric method with Mn(III)-pyrophosphate as the oxidizing agent. It is simpler to use and has a much higher throughput than the commonly used dichromate oxidation and combustion methods. Here, we demonstrate that the method often leads to an underestimation or overestimation of the concentration of common organic compounds in solutions. To our knowledge, no published study has taken this fact into account when analyzing DOC data. Hence, we compared Mn(III)-pyrophosphate-based results with measurements performed with a total organic carbon combustion analyzer for samples of organic and mineral soil horizons of two temperate deciduous forests, of organic soil horizon of a primary-growth hemlock stand, and of a peatland located in New England, USA. The Mn(III)-pyrophosphate method consistently underestimated DOC concentration in soil extracts. We present correction factors for the different types of soil studied. By employing correction factors, we find the method can be an inexpensive, accurate, and high throughput tool to measure DOC in environmental samples.

URLhttp://www.sciencedirect.com/science/article/pii/S0038071714002892
Short TitleSoil Biology and Biochemistry