Determination of Soil Hydraulic Parameters and Evaluation of Water Dynamics and Nitrate Leaching in the Unsaturated Layered Zone: A Modeling Case Study in Central Croatia

Nitrate leaching through soil layers to groundwater may cause significant degradation of natural resources. The aims this study were: (i) estimate hydraulic properties (SHPs) the similar type with same management on various locations; (ii) determine annual water dynamics; and (iii) impact subsoil horizon nitrate leaching. final goal was compare influence different SHPs layering dynamics conducted in central Croatia (Zagreb), at four locations Calcaric Phaeozem, Regosol, Fluvic Phaeozem types. Soil parameters were estimated using HYPROP system HYPROP-FIT software. Water evaluated HYDRUS 2D/3D during a period 365 days. amount under saturated conditions varied from 0.422 0.535 cm3 cm−3 while conductivity 3 cm day−1 990.9 day−1. Even though all have land use climatic physical properties, substantially. velocity transported (HYDRUS 2D/3D) affected by reduced as nitrates are primarily via advective flux. Despite large differences topsoil layers, deeper having SHPs, imposed buffering effect preventing faster downward transport. This contributed very distribution profile end simulation period. case indicated importance carefully selecting relevant multilayered systems when evaluating pollution risk.