EN
The work contains a runctioning analysis of Olszanka catchment situated in the upper course of Wilga river. The analysis was based on hydrochemical parameters. Within two year research period (1992-1994) the seasonal dynamic of primary hydrochemical parameters was examined. The research consisted or 3 elements: 1. - precipitation entering the geosystem; 2. - surface, ground and underground waters; 3. - river runoff - at the end of the geosystem. On the basis of the qualitative (chemieal composition) and quantitative parameters the ion balances were compared and chemical denudation rate was determined. A distinct seasonal dynamics was shown by atmospheric deposition on the area of Olszanka-catchment. In the dry deposition dynamics of acidifying elements (nitrogen and sulphur compounds), the strong correlation occurs beween the atmospheric load and air temperature. Also winter maximum of deposition is observed, which is connected with the pollutant emission during heating season. Two seasonal maximums of wet atmospheric load can be observed. They are correlated with ions conccntration and precipitation. These are: winter maximum - the main factor of which is the winter increase or „acidic” ions, and the summer maximum - connected with summer maximum or precipitation with lower concentration of ions. The annual wet atmospheric load is about 6 g/m². Comparing the dynamics and the range of ions concentration in various water categories, the similarity between underground waters (stable ion composition) and some of ground water samples and river waters (in the closing point of the Olszanka catchment) was observed. At this stage of work crosseway explanation excluding simple increase of ion accumulation was extremely useful; the particular role was played by ions having very low concentration in the underground waters: Na, K, SO₄²⁻ and ions having high concentration like Mg²⁺ and Fe tot. The hypothesis about a hydraulic contact betwccn surfaec waters and underground circulation system was put on. The hypothesis was additionally supported by analysis of hydrostatic pressure in aquifers. On the basis or dynamics and examined ions concentration range differences, the separated subsystems (a - atmosphere, b- river and ground waters, c - underground waters) were differentiated in Olszanka geosystem. Additionally, the river and ground waters subsystem was divided into functional regions. Alier the classical ion balance equations correction with included the possibility of hydraulic contact between underground waters and surface circulation system, the ion balance has been made. It has been stated that charge of ions carried out by the river runoft is 35-37 g/m². Keeping in mind given above the correction and atmospheric load it has been estimated that as a result of the hydrochemical processes about 30 g from a square meter flows out annually from Olszanka-catchment. During dry summer with small outflows bot with heavy precipitation following ions increase: Na, K, and SO₄²⁻ (because of low concentration these ions are typomorphous for underground waters). For all ions, the winter halfyear is a period of high denudation activity. For the summer halfyear falls up to 25% of annual ions flow. In comparison to other catchments from Poland, the results or ionic outflow form Olszanka-catchment are one of the lowest.