Jump to main content
Jump to site search

Issue 5, 2011
Previous Article Next Article

Molecular-level methods for monitoring soil organic matter responses to global climate change

Author affiliations

Abstract

Soil organic matter (SOM) is one of the most complex natural mixtures on earth. It plays a critical role in many ecosystem functions and is directly responsible for sustaining life on our planet. However, due to its chemical heterogeneity, SOM composition at molecular-level is still not completely clear. Consequently, the response of SOM to global climate change is difficult to predict. Here we highlight applications of two complementary molecular-level methods (biomarkers and nuclear magnetic resonance (NMR)) for ascertaining SOM responses to various environmental changes. Biomarker methods that measure highly specific molecules determine the source and decomposition stage of SOM components. However, biomarkers only make up a small fraction of SOM components because much of SOM is non-extractable. By comparison, 13C solid-state NMR allows measurement of SOM in its entirety with little or no pretreatment but suffers from poor resolution (due to overlapping of SOM components) and insensitivity, and thus subtle changes in SOM composition may not always be detected. Alternatively, 1H solution-state NMR methods offer an added benefit of improved resolution and sensitivity but can only analyze SOM components that are fully soluble (humic type molecules) in an NMR compatible solvent. We discuss how these complementary methods have been employed to monitor SOM responses to: soil warming in a temperate forest, elevated atmospheric CO2 and nitrogen fertilization in a temperate forest, and permafrost thawing in the Canadian High Arctic. These molecular-level methods allow some novel and important observations of soil dynamics and ecosystem function in a changing climate.

Graphical abstract: Molecular-level methods for monitoring soil organic matter responses to global climate change

Back to tab navigation

Article information


Submitted
14 Dec 2010
Accepted
11 Feb 2011
First published
17 Mar 2011

J. Environ. Monit., 2011,13, 1246-1254
Article type
Critical Review

Molecular-level methods for monitoring soil organic matter responses to global climate change

X. Feng and M. J. Simpson, J. Environ. Monit., 2011, 13, 1246
DOI: 10.1039/C0EM00752H

Search articles by author

Spotlight

Advertisements