A preliminary study on the salinity and sodicity of soils from Malta and the establishing of an EC (soil: water suspension) to EC (saturated paste) conversion model

Abstract

Soil salinity and sodicity are two important soil characteristics as excessive salt and sodium in soil could have an adverse effect on general soil properties and agricultural production. Salinity is expressed by measuring the electrical conductivity of a soil water saturated paste however as this procedure is time consuming, the electrical conductivity is measured in a soil/water suspension in ratios of 1:1, 1:2 or 1:5. This study was carried out to assess the possibility of measuring the electrical conductivity of various soil/water extracts (1:1, 1:2 or 1:5) and compare it with the electrical conductivity of the soil paste extract for various soils from Malta and produce a model to convert from one method to the other. Fifty soil samples from Malta were analyzed and the results show that the soil water extracts (1:1, 1:2 or 1:5) are linearly correlated with the saturated paste method with a high correlation coefficient (R2 > 0.96) for the majority of the soils except for the heavy clay type soil.