CORRELATION OF NITRATE CONCENTRATION AND WATER LEVEL IN WATER OF KARST ZONE DUG WELLS

The article deals with the peculiarities of variation of NO3 concentration in the water of karst soils. 57% of the analysed wells are polluted by NO3 more than it is allowable rate. The NO3 concentration in the water of glacial lacustrine clays is lower than that in moraine loams. The wells with the exceeded MAC are distinguished by a higher concentration variation during a year. It is presumable that this happens due to the peculiarities of ground water level dynamics in the karst zone. The lowest NO3 concentration was established in the upper water layer down to 0.5 m from the water surface. It increased in deeper layers from the water surface. The variation of NO3 concentration is not only influenced by hydrological regime but also by hydrochemical processes inside the well.