Seasonal water temperature variability of springs from porous sediments in Gryżynka Valley, western Poland

This paper discusses fluctuations in spring water temperature and its correlation to climate and aquifer characteristics. Data from nine springs in the Gryżynka River catchment (Polish Plain) were taken monthly (November 2005 to October 2010). The springs examined in this study are characterised by significant thermal inertia in contrast to air temperature, that is expressed in small temperature amplitudes that range from 1.3°C to 2.3°C. The average temperature of the springs is about 9°C. The research proved that observed groundwater temperature variations on the surface resulted mainly from atmospheric conditions, especially air temperature. The highest water temperatures (up to 10°C) were observed during late summer and early autumn, and the lowest temperature (7.7°C) was observed at the end of the winter period. The range of spring water temperature variability may reflect amount of water contribution from local water recharge in the spring vicinity

The environmental requirements of Crunoecia irrorata (Curtis, 1834) (Trichoptera: Lepidostomatidae) and the potential of the species for use as an indicator: an example from the Vistulian glaciation area

The caddisfly Crunoecia irrorata is a wide-spread species in Europe and inhabits permanent spring areas with pristine or moderately disturbed habitat conditions. However, the pattern of its distribution on the national scale as well as detailed preferences toward water properties are still insufficiently known. To complete this knowledge we analysed at first the distribution of this species in Poland which showed that its extent involves the whole territory, however, with sparse occurrence in most regions and with large areas where the species has not been observed yet. The data compilation also showed that the species’ frequency of occurrence is highest in the central-western region of Poland. Furthermore, its frequency of occurrence decreased towards the east and the northeast. Because the highest frequency of occurrence of this species was found in central-western Poland, the spring sites in this region were used as a model area for the analysis of the hydrochemical conditions associated with the species (25 parameters). The results of the study showed that C. irrorata strongly prefers habitats with low nitrate (NO3) and chloride (Cl) concentrations. In detail, a regression model showed that the probability of occurrence of C. irrorata was only 5 % at concentrations of 32 mg L-1 NO3 and 35 mg L-1 Cl. In contrast, high concentrations of heavy metals (zinc, lead, cooper, chromium, and cadmium) as well as of total iron and manganese did not significantly influence the presence of this species. In conclusion, environmental assessments relating to human health and landscape health can use C. irrorata as an indicator species for biogenic and salt pollution, but the species is not a potential indicator of heavy metals in spring water. Therefore, information on the presence of C. irrorata can serve to preserve crenic ecosystems and their assemblages and can be used to prevent anthropogenic contamination of these ecosystems.</p

Assessment of the quality and irrigation purpose suitability of alluvial water in Erfoud, Morocco

Dry areas are especially exposed to the risk of water shortages and elevated mineralization. High water salinity, caused by low precipitation, high evaporation and human impact, usually strongly limits the use of the water for irrigation. The aim of the study was to assess the quality and irrigation purpose suitability of alluvial water in the Erfoud oasis, Morocco. The samples of water were collected from 20 wells in June 2017. We observed excessive concentrations of many parameters i.a.: NO3, Cd, Ni, Na, NH4, Cl, SO4, Fe, Cr. To determine the possibility to use the water for irrigation purposes, the Sodium Adsorption Ratio (SAR), sodium percentage (%Na), permeability index (PI), Kelly’s ratio (KR), magnesium hazards (MH) and electrical conductivity (EC) were assessed. The values of KR and MH qualified the waters as unsuitable for irrigation purposes. The observed %Na indicates that the groundwater is permissible for irrigation purposes, and permeability index, that it is of moderate quality. However, water classification using the SAR vs EC diagram confirms its high and very high alkali and salinity hazard. The mean EC value of the water was 9.5 mS cm−1

Assessment of the quality and irrigation purpose suitability of alluvial water in erfoud, Morocco

Dry areas are especially exposed to the risk of water shortages and elevated mineralization. High water salinity, caused by low precipitation, high evaporation and human impact, usually strongly limits the use of the water for irrigation. The aim of the study was to assess the quality and irrigation purpose suitability of alluvial water in the Erfoud oasis, Morocco. The samples of water were collected from 20 wells in June 2017. We observed excessive concentrations of many parameters i.a.: NO3, Cd, Ni, Na, NH4, Cl, SO4, Fe, Cr. To determine the possibility to use the water for irrigation purposes, the Sodium Adsorption Ratio (SAR), sodium percentage (%Na), permeability index (PI), Kelly’s ratio (KR), magnesium hazards (MH) and electrical conductivity (EC) were assessed. The values of KR and MH qualified the waters as unsuitable for irrigation purposes. The observed %Na indicates that the groundwater is permissible for irrigation purposes, and permeability index, that it is of moderate quality. However, water classification using the SAR vs EC diagram confirms its high and very high alkali and salinity hazard. The mean EC value of the water was 9.5 mS cm−1

CRENOLOGY OF YOUNG POST-GLACIAL AREAS ON THE EXAMPLE OF LUBUSKIE LAKELAND – OVERVIEW OF RESEARCH

The Polish Lowland is an area with rare and relatively poorly studied springs. The present paper review results of recent studies on springs, their hydrology and environments on Lubuskie Lakeland (5.200 km2) in western part of the Polish Lowland. This area contains over 1,000 springs and seepages outflowing from porous sediments. Most of them are related to thick Pleistocene sediments containing several groundwater bearing layers, which are cut by deep subglacial channels (tunnel valleys). The spring density index is the highest in catchment of the Gryżynka River, with up to 4.8 individual springs and seepages per 1 km2. The most common in the Lubuskie Lakeland are seepages (65%), descending and hillslope outflows. Their water discharge varies from < 0.001 to 50 000 dm3/s. Hydrochemistry of spring waters is dominated by calcium and bicarbonate ions, as well as high concentrations of iron and manganese. Due to the lack of a surface insulation layer, contaminants (various forms of nitrogen) easily migrate to groundwater. Generally, the spring waters have good quality. Moreover continuous observations of the water surface levels in spring supplied water bodies revealed daily fluctuations, which are likely due to evapotranspiration and changes of the filtration coefficient in hyporheic zone

Modelling studies of the conditions of fluidization in the hyporheic zone

Strefa hyporeiczna jest obszarem współdziałania wód powierzchniowych i podziemnych. Warunki w jakich funkcjonuje ta strefa mają ważne znacznie dla organizmów roślinnych i zwierzęcych tam bytujących, ale także dla wymiany wód, ich składu chemicznego oraz reakcji zlewni na opady. W warunkach drenażu wód podziemnych przez wody powierzchniowe może dochodzić do fluidyzacji, czyli upłynnienia osadów dennych budujących strefę hyporeiczną. Zjawisko fluidyzacji zachodzi po przekroczeniu przez gradient hydrauliczny wartości jeden. Korzystając z tego warunku przeprowadzono badania symulacyjne funkcjonowania doliny rzecznej w zależności od wielu parametrów morfologicznych, hydrologicznych czy też hydrogeologicznych. Uwzględniono różnicę poziomu wody między warstwą wodonośną a rzeką, szerokość rzeki, współczynnik filtracji i anizotropię warstwy wodonośnej oraz przepuszczalność pionową strefy hyporeicznej. Realnie występujący zakres zmienności poszczególnych parametrów podzielono na podzakresy wartości niskich, średnich i wysokich. Metodą symulacji komputerowych, za pomocą oprogramowania Visual MODFLOW, poszukiwano takich warunków funkcjonowania doliny rzecznej, dla których może wystąpić zjawisko fluidyzacji. Stwierdzono, że fluidyzacja strefy hyporeicznej zależy proporcjonalnie od różnicy między zwierciadłem wód powierzchniowych i podziemnych. Wykazano, że większej skłonności do fluidyzacji można oczekiwać, gdy warstwa wodonośna ma wysoką przepuszczalność hydrauliczną, strefa hyporeiczna cechuje się niską przepuszczalnością pionową, a szerokość cieku jest niewielka.The hyporheic zone is a contact zone of surface and subsurface waters. One of the specific processes occurring in this zone is hyporheic zone sediment fluidization. The aim of the present study is to define the hydrogeological conditions in a river valley for which the fluidization of the hyporheic zone sediments may occur. The following factors were tested: the difference between the groundwater table and the river water surface, width of the river channel, hydraulic conductivity, and anisotropy of the aquifer sediments, as well as the vertical permeability of the hyporheic zone. The modelling experiments were carried out using the Visual MODFLOW program. The simulations were conducted on three river widths: 3, 6 and 9 m. It was found that the occurrence of fluidization of the hyporheic zone is favoured mainly by the difference between surface water and groundwater table elevation, in the order of 30 m, and the strong anisotropy of aquifers. The likelihood of fluidization occurrence depends on the value of vertical hydraulic conductivity and increases when the hydraulic gradient exceeds 1. The smaller the width of the river, the more favourable conditions for fluidization to occur. It was found that the fluidization of the hyporheic zone depends proportionally on the difference between the surface and ground water table. It has been shown that greater tendency to fluidization can be expected when the aquifer has a high hydraulic conductivity, the hyporheic zone is characterized by low vertical permeability, and the width of the river is small

Water Quality Assessment of a Meromictic Lake Based on Physicochemical Parameters and Strontium Isotopes (87Sr/86Sr) Analysis: A Case Study of Lubińskie Lake (Western Poland)

In 2017, hydrochemical surveys of meromictic Lubińskie Lake (W Poland) and its water inflows were carried out. The lake experienced complete mixing in 2008 due to a series of orkan winds, and since 2015, intensifying worsening of water quality in the lake has been observed. Our aim was to determine the degree of transformation of Lubińskie Lake based on water chemistry and to identify the source of pollution of the lake using strontium isotopes (87Sr/86Sr) as a new chemical tracking tool. The physicochemical analysis confirmed the meromictic character of the lake. The comparison with previous studies (2003 and 2008) showed significant year-to-year differentiation, indicating intensifying eutrophication of the lake&rsquo;s water, both in the epilimnion and the hypolimnion. Nine spring niches, directly supplying the lake, provide water with very high phosphorus and nitrogen concentrations (up to 10 kg of nitrogen and 0.9 kg of phosphorus daily). The strontium isotopes (87Sr/86Sr) analysis indicated that the lake&rsquo;s water was supplied mostly by the springs, and recharge from deep aquifers is of secondary importance. Moreover, strontium isotope data and the relationship between Sr and Cl content support the finding that the high load of nutrients is of anthropogenic origin and reaches the lake through springs