Modelling water flow dynamics using image spectral data

Fertilizers and pesticides are intensively applied in agriculture. However, their use has been documented as a source of contamination of groundwater and surface water. Therefore, it is important to be able to assess the fate and transport of pesticides and nitrates in agricultural soils. Before simulating solute transport and considering chemical species, accurate water flow models for understanding the internal flow pathways are essential. The HYDRUS-2D software package was used to develop a hydrogeological model for simulating the drainage dynamics in a tile-drained agricultural field. A two-dimensional single porosity model was used to simulate the water flow dynamics. The initial parameterization of the hydraulic properties in model relied on in situ and laboratory measurements and satellite data. For estimating the soil water release characteristics, the Campbell function was used. Specifically, the field average Campbell soil-water retention curve (SWRC) was predicted using an existing satellite image model. The estimated SWRC was validated using laboratory data. The suggested approach gave a satisfactory fit to the hydrograph features presenting the potential of remote to be used as an alternative for initial parameterization.