Changes of pH across the rhizosphere induced by roots

  title={Changes of pH across the rhizosphere induced by roots},
  author={Peter Hague Nye},
  journal={Plant and Soil},
  • P. Nye
  • Published 1 February 1981
  • Chemistry
  • Plant and Soil
SummaryPlants that absorb nitrogen as NO3− tend to raise the pH in the rhizosphere. Those absorbing nitrogen as NH4+ or N2 lower the pH. The change in pH near the root surface may be calculated approximately from the H+ or HCO3− efflux and radius of the root; and the pH buffering capacity, moisture content, initial pH and pCO2 of the soil. An accurate equation, solved numerically, also takes account of root hairs, mass flow and slow acid-base reaction in the soil. The pH at the root surface… 
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