Project Title – “Water flow and solute transport in the soil-plant-atmosphere continuum: Upscaling from rhizosphere to root zone”
Salinity is one of the major abiotic stresses limiting growth and productivity of plants, especially in arid and semi-arid areas. The dynamic cross talks between soil salinity, water content, root uptake and evapotranspiration can be simulated by various models, which can be useful tools for soil management and irrigation. The main aim of this project is to obtain insight into the factors that control plant-specific relationships. We hypothesize that the key to obtaining this insight is to resolve the flow and transport processes within the rhizosphere of individual roots, and couple them with flow and transport within the plant’s root system. On the smallest scale we will use magnetic resonance imaging (MRI) to resolve root structures, water content and solute concentration distributions around single roots. On the scale of plant root system, we will use a combination of electrical resistivity tomography (ERT) and local soil sensors. Based on raw ERT data and local measurements a couple inversion approaches will be used. Since the detailed simulation model is based on a mechanistic description of flow and transport processes in the root zone, we expect that it will be able to predict root water uptake in saline soils for different climatic conditions and different soil water availabilities. Validation or falsification of these modeled functions against data from lysimeter experiments will be a central outcome of the project.