Surface charge is a function of organic carbon content and mineralogical compositions of soil

Abstract

A study of the distribution of the electric charges in the surface horizons of two highly weathered soils Fluvaquent and Haplaquept of West Bengal, India was made by direct measurement of adsorption of ions in the presence of varying concentration of electrolyte. The objective of this study was to evaluate charge properties of two highly weathered soil of India. The results show that pH0 varies with soil according to the variation in organic carbon and sesquioxide/allophone content. Organic carbon strongly affects the variation of negative charge with pH, but sesquioxide/allophone is responsible for positive charge variation. Results used the difference between the soil pH values measured in 1M KCl and in water for estimating the point zero charge of the soil and ΔpH values estimating the net surface charge character. Surface charges is a function of organic carbon, clay content, composition of clay and amount of Fe, Al and there oxides.

Keywords

• Soil surface charge
• organic matter
• clay content
• mineralogical composition