Cationic charge ratio (CROSSc) as an index for dispersive soils and irrigation water quality: Advancing beyond SAR and CROSS
Pichu Rengasamy, Ehsan Tavakkoli
Abstract
Soil dispersion and structural stability are critical factors influencing soil health and agricultural productivity. Conventional indices such as Sodium Adsorption Ratio (SAR) and Cation Ratio of Structural Stability (CROSS) are widely used to assess risks associated with soil dispersion and irrigation water quality. However, these indices often fail to capture the complex interactions between cations and the varying nature of soil and water chemistries. This paper introduces the ‘Cationic Charge Ratio for Soil structural Stability (CROSSc)’, a novel index designed to overcome the limitations of SAR and CROSS by providing a more comprehensive and dynamic assessment of dispersive tendencies in soils and irrigation water quality. By integrating the relative dispersive and flocculating charges of cations with soil-specific parameters, CROSSc offers improved predictive capabilities for soil dispersion and irrigation water suitability. Experimental confirmation of the validity of CROSSc in predicting clay dispersion from soils is provided by using the previously published analytical data of several soils from Australia.