Analiza wahań zwierciadła płytkich wód podziemnych na obszarze sandru Brdy

Abstract

Groundwater table fluctuations in the shallow aquifer of the Brda River outwash plain.A b s t r a c t. In the Brda River outwash plain – the largest and the most typical landform of this kind in Poland (Galon, 1972) – there are 10 observation wells of the monitoring network of the Polish Geological Institute – National Research Institute. Analysis of groundwater level observations for the period of 2003–2016, obtained from the monitoring network, show a long-term trend of water table lowering. In most cases the groundwater table has been below the monthly average water level since 2006. In order to correlate the water table and weather data from the meteorological station in Chojnice, numerical simulations were performed using HYDRUS 1D (Šimůnek et al. 2016) – vadose zone software package, based on the Richards equation. A one-dimensionalmodel of the vadose zone was developed to simulate groundwater recharge, applying different bottom boundary conditions (Constant Pressure Head or Free Drainage) considering bare soil evaporation or root water uptake of the grass cover.