b'6Key soil characteristics in water quality and runoff formation modellingStrouhal L1 and Kavka P21CTU in Prague, Faculty of Civil Engineering, Dept. of Landscape Water Conservation, Prague, Czech Republic2CTU in Prague, Faculty of Civil Engineering, Dept. of Landscape Water Conservation, Prague, Czech RepublicWater quality in the streams from agricultural watersheds is closely related to the runoff regime. It differs naturally in wet and dry conditions not only due to the different discharge levels and related solutes dilution. It depends largely from different activity of their sources and flow paths available to reach the stream. From the hydrological point of view the main question for thedynamics of solutes transport is the runoff formation typerapid surface (or shallowsubsurface) runoff or percolation into the deeper layers and discharging as baseflow.Which one of these types occurs depends above all on rainfall intensity patterns and topsoilcharacteristics and conditions. Detailed temporal rainfall patterns were analysed in the Czech Republic using radar and gauging stations rainfall data. Six typical patterns and their spatial distribution with respect to different return periods were designed for the use in water and soil conservation planning. Recently an ongoing project on initial soil conditions has been started as well as assembling the key soil characteristics for the national-wide use. Selected outputs from all these activities are being published via online maps and services. This work was supported by research grants QJ1520265 - Variability of Short-term Precipitation and Runoff in SmallCatchments and its Influence on Water Resources Management; QK1910029 - Antecedentsaturation and design rainfalls as factors of hydrological response in small catchments; TJ01000270ATLAS Hydrologysmart tool for runoff and sediment transport calculation and design of soil conservation measures; TJ02000234 - Physical and hydro-pedological soilproperties of the Czech Republic.50'