Incorporating rhizosphere processes into field-scale (agro)ecosystem models

  • Jonathan Arah
Part of the Developments in Plant and Soil Sciences book series (DPSS, volume 96)


Three different strategies for incorporating rhizosphere processes within field-scale models are compared, taking triple-cropped irrigated rice production as a common system and CH4 emission as a common focus of interest. The strategies may be characterised as homogeneous (model I; root C deposition is added to the bulk soil compartment), areal (model II; roots contribute via aerenchymatous exchange to an increased soil-atmosphere interfacial surface area), and volumetric (model III; roots create around themselves a specific rhizosphere compartment). Model I is simpler than model II, which is simpler than model III. With identical parameters all models lead to similar seasonally integrated CH4 emissions, but when the pattern of emission and the simulated CH4 concentration in the soil is brought into the reckoning, the following order of precedence (greater is better) becomes clear: model III≥model II>model I. Current field-scale models of soil organic matter (SOM) transformation, especially in rice soils, could be improved by taking explicit account of the rhizosphere and the processes which occur within it.

Key words

methane modelling rice up-scaling 


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Copyright information

© Springer Science+Business Media Dordrecht 2002

Authors and Affiliations

  • Jonathan Arah
    • 1
  1. 1.AAT ConsultantsEdinburghScotland, UK

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