Review: Modeling the Effects of Salinity and Sodicity in Agricultural Systems

Soil salinity and sodicity are major concerns in agricultural systems, threatening plant growth in the short term and soil health in the long term. Despite these risks, use of marginal quality water with high salt concentrations is often essential to maintaining food production, especially in arid and semi-arid regions. Leveraging our understanding of basic soil processes and feedbacks is essential for ensuring sustainable use of marginal quality water and land. Models are an important component in effective management, since they allow us to investigate large numbers of potential future scenarios, augmenting our ability to predict the consequences of agricultural practices. In this review, we examine the most advanced models for studying the effects of salinity and sodicity on plant health and soil structure. We place special emphasis on the integration of these frameworks into dynamical models, which can be used to examine how changing climate and irrigation conditions lead to evolving plant and soil responses over time. We highlight important differences in existing modeling frameworks, especially with regard to their relative complexity and suitability for integration into larger climate models. We overview important applications of these models, including studies of localized leaching of salts, complex ion chemistry, the dynamics in layered profiles, and the risk of long-term soil degradation as a result of particular irrigation practices.