Plant and Soil

, Volume 222, Issue 1–2, pp 263–281

A review of rhizosphere carbon flow modelling

  • M.E. Toal
  • C. Yeomans
  • K. Killham
  • A.A. Meharg


Rhizosphere processes play a key role in nutrient cycling in terrestrial ecosystems. Plant rhizodeposits supply low-molecular weight carbon substrates to the soil microbial community, resulting in elevated levels of activity surrounding the root. Mechanistic compartmental models that aim to model carbon flux through the rhizosphere have been reviewed and areas of future research necessary to better calibrate model parameters have been identified. Incorporating the effect of variation in bacterial biomass physiology on carbon flux presents a considerable challenge to experimentalists and modellers alike due to the difficulties associated with differentiating dead from dormant cells. A number of molecular techniques that may help to distinguish between metabolic states of bacterial cells are presented. The calibration of growth, death and maintenance parameters in rhizosphere models is also discussed. A simple model of rhizosphere carbon flow has been constructed and a sensitivity analysis was carried out on the model to highlight which parameters were most influential when simulating carbon flux. It was observed that the parameters that most heavily influenced long-term carbon compartmentalisation in the rhizosphere were exudation rate and biomass yield. It was concluded that future efforts to simulate carbon flow in the rhizosphere should aim to increase ecological realism in model structure.

carbon mechanistic model rhizosphere sensitivity analysis 


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© Kluwer Academic Publishers 2000

Authors and Affiliations

  • M.E. Toal
  • C. Yeomans
  • K. Killham
  • A.A. Meharg

There are no affiliations available

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