Distinct respiratory responses of soils to complex organic substrate are governed predominantly by soil architecture and its microbial community

Fraser, F.C. and Todman, L.C. and Corstanje, R. and Deeks, L.K. and Harris, J.A. and Pawlett, M. and Whitmore, A.P. and Ritz, Karl (2016) Distinct respiratory responses of soils to complex organic substrate are governed predominantly by soil architecture and its microbial community. Soil Biology and Biochemistry, 103 . pp. 493-501. ISSN 0038-0717

[img]
Preview
PDF - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Available under Licence Creative Commons Attribution.
Download (1MB) | Preview

Abstract

Factors governing the turnover of organic matter (OM) added to soils, including substrate quality, climate, environment and biology, are well known, but their relative importance has been difficult to ascertain due to the interconnected nature of the soil system. This has made their inclusion in mechanistic models of OM turnover or nutrient cycling difficult despite the potential power of these models to unravel complex interactions. Using high temporal-resolution respirometery (6 min measurement intervals), we monitored the respiratory response of 67 soils sampled from across England and Wales over a 5 day period following the addition of a complex organic substrate (green barley powder). Four respiratory response archetypes were observed, characterised by different rates of respiration as well as different time-dependent patterns. We also found that it was possible to predict, with 95% accuracy, which type of respiratory behaviour a soil would exhibit based on certain physical and chemical soil properties combined with the size and phenotypic structure of the microbial community. Bulk density, microbial biomass carbon, water holding capacity and microbial community phenotype were identified as the four most important factors in predicting the soils’ respiratory responses using a Bayesian belief network. These results show that the size and constitution of the microbial community are as important as physico-chemical properties of a soil in governing the respiratory response to OM addition. Such a combination suggests that the 'architecture' of the soil, i.e. the integration of the spatial organisation of the environment and the interactions between the communities living and functioning within the pore networks, is fundamentally important in regulating such processes.

Item Type: Article
Keywords: Soil respiration; Microbial community; Soil architecture; Complex substrate; Bayesian belief network
Schools/Departments: University of Nottingham, UK > Faculty of Science > School of Biosciences
Identification Number: https://doi.org/10.1016/j.soilbio.2016.09.015
Depositing User: Eprints, Support
Date Deposited: 03 Nov 2016 09:31
Last Modified: 04 Nov 2016 03:53
URI: http://eprints.nottingham.ac.uk/id/eprint/38483

Actions (Archive Staff Only)

Edit View Edit View