Andrzej Kostrzewski

The Gardno Lake catchment on Wolin Island is located within the Wolin Range micro-region. Its coastal location and early glacial terrain within the temperate climate zone are the distinguishing features of this catchment. The catchment is non-run-off in character, and its area is dominated by beech forests and affected by a small degree of human impact. In the Gardno Lake catchment, atmospheric precipitation undergoes both physical and chemical conversion during its permeation in the beech forest zone, and then during infiltration through the slope cover, percolation to aquifers and subsequent drainage down towards the lake. A pattern of increased mineral content and higher pH at subsequent stages of water circulation were also identified. In the period 2010 – 2014, on a monthly basis, waters at the atmospheric stage ( precipitation, throughfall, stemflow ), transitional stage ( throughflow ), and lithospheric stage ( groundwaters, lake waters ) were examined in the Gardno  Lake catchment. The research study described herein allowed to determine changes in water physical and chemical characteristics at individual stages of its cycle and discrete solute loads reaching the studied catchment area. The annual variability of water mineral content circulating in the Gardno Lake geoecosystem – presented in the paper – was calculated via the total concentration of biogenic ions (NO 3 – , NH 4 + , K +), denudation-originated ions ( SO4 2– , Ca 2+, Mg 2+), and ions resulting from a large supply of marine aerosols ( Cl –– Na + ).

The endorheic catchment of Lake Gardno is located in  northwestern Poland on the Wolin Island at a distance of 0.2 km from the Baltic Sea cliff coast. Within the Lake Gardno catchment, on a monthly basis, water with its quantitative aspects and physicochemical properties was examined at every stage of its circulation. For the diagnosis of the circulation of water and solutes, as well asits mechanisms it was essential to determine the seasonal variability of the concentration of biogenic (NO₃^-, NH₄⁺, K⁺) and denudative ions (HCO₃^-, SO₄^2-, Ca²⁺, Mg²⁺), and ions supplied primarily from sea aerosols (Cl^-, Na⁺). At the first stage of the water cycle, atmospheric water reaching tree-tops has the lowest mineralization at 1.8  mS·m^–1. Throughfall and stemflow lead to an increase in the mineralization up to 8.7  mS·m^–1 on average. The next stage, connected with the underground water circulation and leaching of soils, increases the mineralization of water up to 46.3  mS·m^–1. The lake water was mineralized at 36.7  mS·m^–1. The seasonal variability of the hydrochemical activity of water circulating within the Lake Gardno geoecosystem was represented by groups: with increased concentrations of solutes, with average concentrations of solutes and with reduced concentrations of solutes. The analyzed geoecosystem is characterized by a high concentration level of chloride and sodium ions at every stage of water circulation, which is related to the supply of sea aerosols.

The paper discusses the spatial variability of the physical and chemical properties of river water in the upper Parsęta catchment (West Pomerania, Poland) during rising spring flows. Making use of data generated by 6 hydrochemical surveys, the studied waters were classified based on so-called fuzzy clustering methodology and attempts were made to interpret their spatial distribution. The obtained results show that during spring rising flows meteorological and hydrological conditions present in the period prior to sampling have a major impact on the water chemistry of the upper Parsęta catchment. These prior conditions significantly weaken the spatial variability of lithological and hydrogeological characteristics which is clearly perceptible in the case of low outflows.

The organisation and performance of research on geomorphological processes should be based on the methodological and methodical grounds of the empirical sciences. A well-organised observation in the form of geomorphological monitoring forms the grounds for the collection of observational data. Actually, it is not an option to consider the geoecological approach in the study of present-day geomorphological processes. This is a methodological must. Adopting a certain concept of the geoecosystem seems to be a good option in research on present-day geomorphological processes (Kostrzewski 1993). A geoecosystem is a unit of geographic space with varying size and structure. This geomorphological monitoring stands for the organisation and conduct of research on geomorphological processes (considered to be dominant) and relevant conditions (weather-related, hydrological) based on a standardised measurement system in order to obtain reliable data aimed to assess current research studies and plan future studies. Currently in Poland, geomorphological monitoring is conducted at scientific research sites; for example, at selected high schools and as part of the Integrated Environmental Monitoring Network in Poland, which is a subsystem of Poland’s National Environmental Monitoring Network. The data obtained from geomorphological monitoring sites, verified on the grounds of accepted statistical tests, forms the basis for the analysis and assessment of a given geoecosystem and its operation, taking into account observed climate changes and increasing human impact.

The presented results constitute a summary of a five-year study conducted from 2009 to 2013 in the upper catchment of the Lewińska Struga stream. Weekly research on the physical and chemical properties of Lewińska Struga waters at the Domysłów profile was combined with seasonal hydrochemical studies conducted in the following five flow-through lakes : Warnowo, Rabiąż, Czajcze, Domysłowskie and Żółwińskie. Across young glacial areas of the Polish Lowland, a drainage network is often produced by a fluvial-lacustrine system, in which a river links subsequent lakes via short sections. In such cases, this fluvial transport of solutes is sometimes disturbed in lakes, which are both their source and deposition area. The main research strategy of the paper was aimed at determining the functioning of the fluvial-lacustrine system of Lewińska Struga stream on Wolin Island. This paper also discusses the dynamics of fluvial transport of solutes carried with Lewińska Struga waters.

The research sought to determine the range of conversion of the chemical composition of precipitation in a beech stand located in the Gardno Lake catchment ( Wolin Island ) and a pine stand in the Czarne Lake catchment ( Upper Parsęta catchment, West Pomerania Province ). The presented results cover three hydrological years : 2012, 2013 and 2014. The research focused on the chemical composition of bulk precipitation ( in the open ), throughfall and stemflow ( in a forest ). The obtained results confirm that after precipitation has had contact with plant surfaces there is an increase in its mineral content. This is due to the process of enrichment of throughfall and stemflow with elements leached out of needles and leaves ( K +, Mg 2+ ) and coming from dry deposition ( NH 4 +, Cl –, Na +, Mg 2+, SO 4 2– , NO 3 – ) washed out from plant surfaces. The research, based on the canopy budget model, indicates that in the case of potassium, its load leached out of needles and leaves accounted for 75.6 % and 73 %, respectively, of its total deposition on the forest floor. Calcium leaching was not detected in either of the two stands. In comparison with potassium, the range of magnesium leaching was smaller and amounted to 34 % under beech and 26.5 % under pine. As to loads of potassium and magnesium in the beech stand, they were more than twice as large as the ones observed in the pine stand. In spite of the fact that coniferous trees capture aerosols present in the air much more effectively, a higher mineral content was recorded in the beech stand. It applies primarily to ions of marine origin ( Cl –, SO 4
2– , Na +, Mg 2+ ). It was only when ammonium ions originated from agriculture that their higher concentrations and loads were found in the pine stand.