Improved construction of antimony micro‐electrodes for measuring pH‐changes at the soil‐root interface (rhizosphere)

Abstract

An improved construction of antimony (Sb) nricroelectrodes was carried out to obtain higher resolution, accuracy and better suitability for measuring pH‐changes in the rhizosphere. The Sb‐microelectrodes in conjunction with a standard calomel reference electrode are used to measure the pH of the soil‐root interface. A linear correlation (r²=0.99) between the Sb‐electrode potential (E_Sb ) and pH‐values (glass electrode) was found in different buffer solutions as well as in soils. Sb‐microelectrodes were found suitable for measuring pH‐changes in the rhizosphere whether from pot or field experiments. More accurate results would be obtained with high resolution in moistened soils than in dry soils.

Key words:

• Sb‐microelectrode
• construction method
• pH‐change
• rhizosphere
• buffer solution