Skip to Main content Skip to Navigation
Journal articles

Microscale Heterogeneity Explains Experimental Variability and Non-Linearity in Soil Organic Matter Mineralisation

Abstract : Soil respiration represents the second largest CO 2 flux from terrestrial ecosystems to the atmosphere , and a small rise could significantly contribute to further increase in atmospheric CO 2. Unfortunately, the extent of this effect cannot be quantified reliably, and the outcomes of experiments designed to study soil respiration remain notoriously unpredictable. In this context, the mathematical simulations described in this article suggest that assumptions of linearity and presumed irrelevance of micro-scale heterogeneity, commonly made in quantitative models of microbial growth in subsurface environments and used in carbon stock models, do not appear warranted. Results indicate that microbial growth is non-linear and, at given average nutrient concentrations, strongly dependent on the microscale distribution of both nutrients and microbes. These observations have far-reaching consequences, in terms of both experiments and theory. They indicate that traditional, macroscopic soil measurements are inadequate to predict microbial responses, in particular to rising temperature conditions, and that an explicit account is required of microscale heterogeneity. Furthermore , models should evolve beyond traditional, but overly simplistic, assumptions of lineari-ty of microbial responses to bulk nutrient concentrations. The development of a new generation of models along these lines, and in particular incorporating upscaled information about microscale processes, will undoubtedly be challenging, but appears to be key to understanding the extent to which soil carbon mineralization could further accelerate climate change.
Complete list of metadata

Cited literature [17 references]  Display  Hide  Download
Contributor : Gestionnaire Hal-Upmc Connect in order to contact the contributor
Submitted on : Friday, February 12, 2016 - 12:28:22 PM
Last modification on : Friday, October 15, 2021 - 1:39:49 PM
Long-term archiving on: : Saturday, November 12, 2016 - 7:25:50 PM


Publication funded by an institution


Distributed under a Creative Commons Attribution 4.0 International License



Ruth E. Falconer, Guillaume Battaia, Sonja Schmidt, Philippe Baveye, Claire Chenu, et al.. Microscale Heterogeneity Explains Experimental Variability and Non-Linearity in Soil Organic Matter Mineralisation. PLoS ONE, Public Library of Science, 2015, 10 (5), pp.e0123774. ⟨10.1371/journal.pone.0123774⟩. ⟨hal-01273357⟩



Record views


Files downloads