The improved understanding of processes controlling the transfer of water near the land surface, including soil-plant-atmosphere interactions, is necessary for their correct description and modelling. Due to time and input parameters constraints, the description of the water movement through soil is usually incorporated in hydrological models in a very simplified way. The more detailed analyses of model efficiencies are generally available only for small-scale areas and vegetation season. Better understanding of soil moisture dynamics will lead to a more efficient hydrological forecast concerning both large scale floods caused by long-lasting rain and small-scale flash floods.
The subject matter is addressed through an analysis of soil-plant-atmosphere system responses to varying atmospheric forcing and subsequent modelling of the key hydrological processes in the individual compartments of the hydrological system at the relevant spatio-temporal scales. The attention is paid especially to:
- Research on various types of the soil moisture accounting models with the focus on their year-round applicability in larger areas;
- Accurate measurements of transpiration fluxes in trees (using the method of heat field deformation imaging);
- Study of the possible employment of the actual retention capacity as a basis for the hydrological forecasting system – identification of the catchment threshold behaviour causing sudden substantial runoff;
- Relation of water extraction by the root system and soil water in the vadose zone of the soil profile, concerning both vegetation and dormant season;
- Study and description of interception of water by the forest canopy in head water regions in the Czech Republic, concerning both summer and winter season;
- Development, testing and application of model of the cloud and fog water deposition on the forest canopy;
- Description of the rainfall-runoff formation form the basin taking into account the evapotranspiration and soil water movement under the preferential and gravitationally destabilized conditions.