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EN
A three-dimensional baroclinic sigma-coordinate model was applied to study the circulation and thermohaline variability in the coastal zone in the south-eastern Baltic Sea. The model is based on the Princeton Ocean Model code of Blumberg & Mellor (1987), known as POM, and has the horizontal resolution of ~5 km and 24 sigma-levels in the vertical. The hydrodynamic conditions and variability of water and salt exchange between the Gulf of Gdansk and the Baltic Proper, and the renewal of water masses in the Gulf of Gdansk due to atmospheric forcing are analyzed. The numerical simulations were performed with real atmospheric forcings as well as with homogeneous (spatially uniform) wind fields over the whole Baltic Sea. The numerical simulations showed that the atmospheric forcing (winds) can play a significant role in shaping the renewal of bottom saline waters in the Gulf of Gdansk. Two regions of inflow/outflow of saline waters responsible for the salinity regime were located. The overall water exchange between the Gulf and the Baltic Proper as well as the exchange of saline bottom waters appear to be strongly dependent on wind conditions. The net flux of water of salinity >9 PSU is of the order of 48000-100000 m3 s-1. SE, E, S and NE winds were found to exert the greatest influence on salinity conditions in the Gulf of Gdansk. Estimates of saline (salinity >9 PSU) water residence time based on the model simulation yielded values from 46 days for SE winds to 153 days for NW winds.
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Content available remote Unusual Baltic inflow activity in 2002-2003 and varying deep-water properties
88%
EN
The unusual sequence of inflow events into the Baltic Sea that occurred in 2002 and 2003 includes the first ever important baroclinic inflow to be described (August 2002), the Major Baltic Inflow (January 2003), which gave rise to the highest oxygen levels in the Gotland Deep since the 1930s, and the baroclinic inflow (August 2003) that elevated the Gotland Basin deep water salinity to values last observed in 1977, and caused the surface salinity to rise again. From these trend changes, salt residence times were estimated at about 20 years in the deep waters and 30 years above the pycnocline. Ventilation of the remote Karlsö Deep took until 2005, two years after the inflow event responsible, at a time when the Bornholm and Eastern Gotland Basins were already returning to stagnation.
EN
We analyse the factors used for assessing groundwater intrinsic vulnerability to pollution in the mean residence time estimation method, providing a final vulnerability evaluation. The following factors were analysed: depth to shallow groundwater, effective precipitation infiltration coefficient, terrain inclination, volumetric water content of soils and rocks in the unsaturated zone and volumetric water content of the topsoil. GIS surveys were performed for two geomorphologically diverse regions: a highland piedmont and a lowland plain in Poland (Central Europe). In both cases, groundwater had spatially diverse vulnerability to contamination. The research method used relied on determining the percentage participation of the area with particular values of the parameters analysed in areas of different degrees of vulnerability. Knowledge of the extent and distribution of variability of the parameters analysed in areas of particular degrees of vulnerability helps explain the causes of spatial variation in groundwater intrinsic vulnerability to contamination in given areas.
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tom 02
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nr 1-4
EN
The ecohydrological approach can be applied to reconstructed wetlands where an appropriate vegetation design is needed in order to optimise hydraulic behaviour, water quality improvement and biodiversity increase. The purpose of this study is to examine the hydraulic effects of different development stages of vegetation in a demonstrative reconstructed wetland in Italy characterised by a central canal and two vegetated lateral shallow zones. Tracer tests were carried out in different vegetation conditions. The residence time distributions were analysed using several parameters. As expected, the results show that with more developed vegetation the hydraulic dead zones increase. On the other hand, a moderate increase of vegetation density doesn’t hinder the flow, but rather increases dispersion number. A proper design has to avoid hydraulic short circuiting and provide a good distribution of the flow especially in the vegetated zones.
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tom Vol. 56, no. 3
349-359
EN
Aquifer vulnerability maps are valuable tools for communicating concerns about the level of groundwater pollution hazard to local landuse planners and to the general public. Groundwater vulnerability to contamination in the Kampinoski National Park (KNP) area in central Poland was evaluated as a basis for developing appropriate protection strategy for the groundwater resources and management in recreation areas located near Warsaw. Assessment was accomplished using U.S. EPA DRASTIC and the residence time in the unsaturated zone of a conservative pollutant. The final DRASTIC values have been grouped into medium (37 % of area) and medium high (52 %) intrinsic vulnerability categories. The residence time in the unsaturated zone is classified in 11 intervals, ranging from 30 days to 30 years, but nearly 75 % of the study area is characterized by intervals from 1 to 3 years.
EN
The points of the national network of groundwater monitoring comprise a stable benchmarks in quality and quantity monitoring. The obtained data (tritium and δ18O) are important for understanding the groundwater cycling and are indirect indicators of aquifer vulnerability to anthropogenic pollution. The goal of this paper is to present the relation of the tritium content and delta value of stable isotopes of oxygen against the groundwater sampling depth in 2004–2012. It is demonstrated that the remains of “nuclear” tritium concentration is still present in groundwater as a tritium peak at depths around 30 m. Determination of dynamics of recharge in groundwater bodies, based on national network observation points is associated to the estimation of the groundwater residence time in aquifers and remains one the vital problem of hydrogeology.
EN
Bank filtration (BF) is a nature-based solution that can provide safe drinking water at a low cost, in being a green technology that benefits from natural ecosystem services and saves energy as well. The objective of the present paper is to evaluate the potentiality of a new site for bank filtration along a surface water source that experiences periods of both high and low flow. This site is located along the Ismailia Canal in the eastern Nile Delta fringe of Egypt. The present evaluation is based on exploratory drilling, installation of monitoring infrastructure and monitoring of both water level and water quality parameters for one year. The site has favourable hydrogeological conditions; the mean hydraulic conductivity of aquifer materials (sand and gravel) is 18.98 m/day. Moreover, there is a hydraulic connection between canal and aquifer; under steady conditions, the canal feeds the aquifer. Using different tracers, such as Cl, EC, Sr and SO4, the average bank filtration share is in excess of 95%. BF has reduced the particulates (turbidity) by 96%, total coliform by 99 % and total organic carbon (TOC) expressed as ultra-violet absorbance at 254 wavelengths (UVA254) by 44%. In addition, BF reduces concentrations of disinfection by-products due to its ability to remove organic matter. The potential degradation of TOC in the canal bed sediments may cause the release of iron (Fe) and manganese (Mn) to the bank filtrate water; this process is exaggerated during low-flow periods. Compared to conventional water treatment, BF is a cost-effective green technology, because no chemicals are used and no waste products are generated.
PL
Mapy podatności naturalnej wód podziemnych na zanieczyszczenia stanowią wizualizację oceny podatności wód podziemnych na zanieczyszczenia. Są one jednym z najważniejszych elementów uwzględnianych przy podejmowaniu decyzji odnośnie zagospodarowania terenu i obiektów potencjalnie uciążliwych dla środowiska. Badania podatności wód podziemnych na zanieczyszczenia zostały przeprowadzone na obszarze Kampinoskiego Parku Narodowego (skala regionalna) oraz na wytypowanym poligonie w pobliżu Wiktorowa w Kampinoskim Parku Narodowym (około 30 km2) w skali lokalnej. Ocenę podatności naturalnej przeprowadzono przy zastosowaniu zmodyfikowanej metody DRASTIC oraz na podstawie szacunku czasu przesączania się zanieczyszczeń konserwatywnych. Uzyskane rezultaty wskazują, że rezultat oceny zależy od wykorzystanej metody, stopnia rozpoznania warunków hydrogeologicznych, zastosowanych uproszczeń oraz wyznaczonego celu badań.
EN
Maps of natural groundwater vulnerability to contamination illustrate the assessment of natural groundwater vulnerability. They are also one of the important components that are taken into consideration while making a decision as regards the site management and objects potentially troublesome for the environment. The researches of natural vulnerability were conducted for the area of the Kampinoski National Park (on a regional scale) and for the area (about 30 km2) near Wiktorów (part of the Kampinos National Park) on a local scale. The assessment of vulnerability has been performed with the use of the modified DRASTIC method and calculations of the time migration method of a contaminant through the unsaturated zone. The results of the study indicate that the evaluation of natural groundwater vulnerability to contamination depends on the following factors: research methodology, degree of area recognition, applied simplifications and the purpose of research.
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