Salinity and salt contamination assessment using anion-exchange resin membranes
Exchange resins have the ability to sorb ions directly from the soil solution and, thereby show promise as a method to assess plant available nutrients. In salt affected soils, knowing the relative levels of various anions is useful in predicting the type of salts present and the potential for toxicity of specific anions, most importantly boron (B). The objective of this study was to apply the anion exchange membrane (AEM) burial technique to saline soils to rapidly assess anion composition and compare this to standard saturated paste extractions. Soils with a wide range in natural salinity levels were initially investigated. AEM extractable borate, chloride and sulfate were generally well related to the soluble levels found in saturated paste extracts (R2=0.79, 0.81 and 0.75, respectively). Toxic limit for boron in the saturated paste extract corresponded to 0-12 ug/cm2 in the AEM test. AEM testing performed as well as the saturated paste method in distinguished between soils contaminated by native salinity and saltwater brine Spills. AEM testing is simple and rapid and show promise as an in-field method for spill site diagnosis.
Soils and Crops Workshop