The article presents the results of preliminary geochemical and mineralogical studies of technogenic soils (Technosols) of abandoned iron ore mines on the Ławęczna Hill near Miedziana Góra in the Holy Cross (Świętokrzyskie) Mountains, southcentral Poland. The results of chemical analyses (XRF) were used to calculate the soil enrichment factors of arsenic, copper, iron, lead and zinc, and compare the element concentrations to their levels in uncontaminated soils across Poland and in the city of Kielce. The highest values of soil enrichment factors of metals (As 27.699, Ni 26.455, Cu 9.353, Zn 3.344, Pb 0.62) were recorded for the sand fraction composed of iron oxyhydroxides and hematite, whereas the lowest (Ni 0.22, Cu 0.069, Zn 0.007, Pb 0.028) for the clay–silt and sand fractions, which were primarily composed of calcite and quartz as well as for gravel fraction. The clay-silt fraction shows the highest enrichment in arsenic (27.69). The examined metals and arsenic show positive geochemical anomalies.
Urban reservoirs can receive high loads of chemicals, including persistent contaminants and eutrophication-promoting nutrients. To maintain their economic and recreational use, implementation of various restoration methods is often required. The Maltański Reservoir (Poland, Europe), a small, shallow and dammed urban water body, undergoes complete draining every four years as part of its restoration procedure. Here, we investigated the phosphorus (P) content and its fractions just before the reservoir was drained and after it had been completely filled with water again. As demonstrated, the highest accumulation of P occurred at sites through which the main water flow is directed. Calcium-bound and residual P constituted the largest proportion of P fractions. A shift in P fractions after the reservoir was drained and sediments were left without water for at least 4 months was observed. A decrease in phytoplankton utilized NH4Cl-P, Fe-P and NaOH-P fractions was found and followed a simultaneous increase in nearly biologically inaccessible HCl-P and practically biologically inactive residual P fractions. Our study demonstrates that complete drainage of the Maltański Reservoir may additionally decrease the risk of internal P loading through shifts in its fractions.
The aim of the study was to determine the influence of urban agglomeration on a small, natural water reservoir which, as a result of the expansion of the city of Poznań, has become an urban lake. In the vegetation period 2015, the chemistry of its water was studied, and in September additional samples of bottom sediments, plants and fish were collected for analysis in order to determine the content of heavy metals. In terms of productivity, no significant influence of the catchment was recorded. In the 1980s the lake was defined as eutrophic, and in 1996 as α-mesotrophic and such a state continues until today. This is the result of protective activity undertaken by its new owner. The adverse influence of the urbanization of the surrounding areas was reflected by the increased content of lead in particular elements of this ecosystem, that is, in bottom sediments, plants and fish muscles.
Municipal water reservoirs improve urban landscape architecture, providing water for various domestic uses. At the same time, they are under strong human impact affecting water quality and biological conditions. We investigated the level of metal accumulation (Cd, Co, Cr, Cu, Fe, Ni, Mn, Pb and Zn) in sediments as well as mussels Anodonta anatina and Unio tumidus and common reed Phragmites australis collected from 8 sampling sites at Malta Reservoir (Poznań, Poland) just before the complete drainage of the lake in November, 2012. In all investigated samples metal concentrations ranked in decreasing order: Fe>Mn>Zn>Cu>Cr>Ni>Pb>Co>Cd. Accumulation of toxic metals in roots of P. australis was higher than in soft tissues of mussels although it did not exceed phytotoxic levels. Roots of P. australis accumulated high levels of Cr (mean 9.7 μg g-1) and Ni (mean 5.7 μg g-1). U. tumidus accumulated higher concentrations of Cr (mean 1.1 μg g-1) than A. anatina indicating potential use in bioindication of this metal. The present study provides the most recent information on metal content in sediments and biota in Malta Reservoir and, further, suggests that this reservoir is capable of accumulating toxic elements from preceding water bodies (Lake Swarzędz) and surrounding residential areas.
Trapa natans (water chestnut) is an aquatic, thermophilic plant whose decline has been observed in many localities in central Europe during the last decades. In this paper, we present a description of two new T. natans subfossil sites located outside its present northern distribution in Poland. High-resolution analysis of plant macrofossils supported by geochemical analysis were undertaken to reconstruct the palaeoecological habitat and examine the cause of the late Holocene decline of T. natans that took place ca. 4000 calibrated years before AD 1950 (cal. yr BP) in a paleolake, presently the Bagno Kusowo bog. Its disappearance was a consequence of terrestrialisation and the development of peatland. In paleolake sediments covered by the peat layer in the Mechacz Wielki bog, T. natans macrofossils were found from before ca. 3300 cal. yr BP. The decline of T. natans could have resulted from the changes and development of other plant communities where the dominant role was played by Stratiotes aloides and Nymphaea sp. In our study sites, T. natans occurred together with Potamogeton crispus, Potamogeton obtusifolius, Nymphaea alba, and Nuphar sp. in eutrophic water dominated by Ca2+, Fe3+, and Al3+ ions. Our palaeobotanical and geochemical results align with the contemporary conditions of T. natans habitat.
In arid areas, with rivers functioning episodically, alluvial resources are the main source of water. Considering the intensified regulation of discharge in montane catchments, supplying the intermittent rivers, in the nearest future alluvial aquifers will gain key importance for the functioning of people in arid zones. The research aimed to investigate the diversified chemistry of alluvial waters typical of large intermittent river valleys in hot arid zones as well as to analyse processes determining the water chemistry and affecting its diversity. The detailed study, carried out in October 2015, covered the Draa river valley (1100 km total length) in the region of the Mhamid Oasis. The examined water was sampled from all wells found in the study area. Concentrations of the main cations: Ca2+, Mg2+, K+, Na+, NH4+, and Li+, anions: Cl−, SO42−, HCO3−, and NO3−, as well as trace elements: Al, As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr, and Zn, were identified. Results were analysed with statistical, hydrochemical, and geochemical modelling methods. Alluvial waters of the eastern and western part of the oasis differed in concentrations of numerous components, what resulted from the regulation of irrigation. Specific electrical conductivity showed a 3.5-fold increase, from 3800 to 13800 μS/cm, consistent with the direction of water flow in the oasis, from east to west. Even a greater rise was observed for ions: Cl− (6x), Na+ (5.5x), Mg2+ (5.0x), Ca2+, and SO42− (3.5x). Such a composition indicated multiionic hydrochemical type of waters dominated by Na+ and Cl−. Additionally, high Pearson correlation coefficients were recorded for Na+ and Cl− (0.98) as well as Mg2+ and Cl− (0.97). The saturation index suggested that the main water components originated from dissolving of minerals such as halite, anhydrite, sylvite, and gypsum. Groundwater chemistry in the Mhamid Oasis was determined mainly by geogenic processes, such as dissolving of evaporates, precipitation of carbonate minerals, and ion exchange.