Applications of stable isotope ratio mass spectrometry in cattle dung carbon cycling studies

Jennifer A. J. Dungait, Roland Bol, Elisa Lopez-Capel, Ian D. Bull, David Chadwick, Wulf Amelung, Steven J. Granger, David A. C. Manning, Richard P. Evershed

Research output: Contribution to journalArticle (Academic Journal)

23 Citations (Scopus)

Abstract

Understanding the fate of dung carbon (C) in soils is challenging due to the ubiquitous presence of the plant-derived organic matter (OM), the source material from which both dung-derived OM and soil organic matter (SOM) predominantly originate. A better understanding of the fate of specific components of this substantial source of OM, and thereby its contribution to C cycling in terrestrial ecosystems, can only be achieved through the use of labelled dung treatments. In this short review, we consider analytical approaches using bulk and compound-specific stable carbon isotope analysis that have been utilised to explore the fate of dung-derived C in soils. Bulk stable carbon isotope analyses are now used routinely to explore OM matter cycling in soils, and have shown that up to 20% of applied dung C may be incorporated into the surface soil horizons several weeks after application, with up to 8% remaining in the soil profile after one year. However, whole Soil delta C-13 values represent the average of a wide range of organic components with varying delta C-13 values and mean residence times in soils. Several stable C-13 isotope ratio mass spectrometric methods have been developed to qualify and quantify different fractions of OM in soils and other complex matrices. In particular, thermogravimetry-differential scanning calorimetry-isotope ratio mass spectrometry (TG-DSC-IRMS) and gas chromatography-combustion-IRMS (GC-C-IRMS) analyses have been applied to determine the incorporation and turnover of polymeric plant cell wall materials from C-4 dung into C-3 grassland soils using natural abundance C-13 isotope labelling. Both approaches showed that fluxes of C derived from polysaccharides, i.e. as cellulose or monosaccharide components, were more similar to the behaviour of bulk dung C in soil than lignin. However, lignin and its 4-hydroxypropanoid monomers were unexpectedly dynamic in soil. These findings provide further evidence for emerging themes in biogeochemical investigations of soil OM dynamics that challenge perceived concepts of recalcitrance of C pools in soils, which may have profound implications for the assessment of the potential of agricultural soils to influence terrestrial C sinks. Copyright (C) 2010 John Wiley & Sons, Ltd.

Original languageEnglish
Pages (from-to)495-500
Number of pages6
JournalRapid Communications in Mass Spectrometry
Volume24
Issue number5
DOIs
Publication statusPublished - Mar 2010

Cite this

Dungait, J. A. J., Bol, R., Lopez-Capel, E., Bull, I. D., Chadwick, D., Amelung, W., Granger, S. J., Manning, D. A. C., & Evershed, R. P. (2010). Applications of stable isotope ratio mass spectrometry in cattle dung carbon cycling studies. Rapid Communications in Mass Spectrometry, 24(5), 495-500. https://doi.org/10.1002/rcm.4332