Potential effect of pH on the leaching of heavy metals from sediments of the Carpathian dam reservoirs

Eutrophication processes occurring in the Carpathian dam reservoirs (southern Poland) has resulted in a drastic increase of incidences of decrease of pH and oxygen content in near-bottom water, which may affect metal remobilization from the sediment. The study is aimed to determine the buffer capacity and effects of lowering of pH on remobilization of heavy metals (Cd, Pb, Cu, Zn, Mn and Fe) from sediments of the Dobczycki Reservoir (DR), the Czorsztyński Reservoir (CR), and the Rożnowski Reservoir (RR), the right side tributary of the Vistula River. Buffering capacity and the leaching of heavy metals from sediments accompanied with an increase in acidity were analyzed in 0-0.24M solutions of HNO3. Studied sediments had a good buffer capacity. Buffer capacity of sediments at studied sites of the DR and CR were different due to varied sediment composition. The reservoir sediments had a varied ability to release the metals with increasing acidity. At pH ~ 5 and pH ~ 3, a considerable leaching of Mn (up to 60% and 85% of the total amount, respectively), Cd (up to 35% and 56% respectively), Pb (up to 25% and 39), the lower leaching of Cu (up to 18% and 30%) and Zn (up to 14%  and 20%) and slight one of Fe (below 5%) were found. The lowering pH of the water- sediment system caused by eutrophication processes may affect the mobilization of certain heavy metals (mainly Mn, Cd and Pb) from the sediment into the water column of studied Carpathian reservoirs

Response of Cladocera Fauna to Heavy Metal Pollution, Based on Sediments from Subsidence Ponds Downstream of a Mine Discharge (S. Poland)

Mining is recognized to deeply influence invertebrate assemblages in aquatic systems, but di erent invertebrates respond in di erent ways to mining cessation. Here, we document the response of the cladoceran assemblage of the Chechło river, S. Poland (southern Poland) to the cessation of Pb-Zn ore mining. The aquatic system includes the river and associated subsidence ponds in the valley. Some ponds were contaminated during the period of mining, which ceased in 2009, while one of the ponds only appeared after mining had stopped. We used Cladocera to reveal how the cessation of mine water discharge reflected on the structure and density of organisms. A total of 20 Cladocera taxa were identified in the sediment of subsidence ponds. Their density ranged from 0 to 109 ind./1 cm3. The concentrations of Zn, Cd, Cu and Pb were much higher in sediments of the ponds formed during peak mining than in the ponds formed after the closure of the mine. Statistical analysis (CCA) showed that Alonella nana, Alona a nis, Alona sp. and Pleuroxus sp. strongly correlated with pond age and did not tolerate high concentrations of heavy metals (Cu and Cd). This analysis indicated that the rate of water exchange by the river flow and the presence of aquatic plants, a ect species composition more than pond age itself

Rotifer Diversity in the Acidic Pyrite Mine Pit Lakes in the Sudety Mountains (Poland)

The diversity of rotifers was studied in three artificial water bodies (Azure Lake, Yellow Lake, and Purple Lake), which were once pyrite mines. The physicochemical parameters and the zooplankton composition of the water were determined. Azure Lake had a pH of 3.4–6.9, conductivity values of 165–194 µS cm− 1, and low concentrations of sulphate, calcium, magnesium, copper, and iron, while the other lakes had a pH of 2.6–2.9, a conductivity of 1636–3400 µS cm− 1, and high concentrations of sulphate (up to 2863 mg dm− 3), Cu (up to 2650 µg dm− 3), and Fe (up to 178.3 mg dm− 3). The rotifer community in the lakes comprised 27 taxa (15 in Azure Lake, 13 in Purple Lake and 14 in Yellow Lake). We also found two species that are rarely observed in Poland (Aspelta cincinator and Elosa spinifera), and three species commonly found in acidic water (E. worallii, Cephalodella delicata, and C. hoodi). The types of rotifers in Azure Lake differed from those in the other two lakes. The Shannon–Weaver biodiversity index (H′) was the highest in Purple Lake (H′ = 1.255) and lowest in Azure Lake (H′ = 0.455). The effect of some of the physicochemical parameters on rotifer diversity is discussed

Genome instability in Chironomus annularius sensu Strenzke (Diptera, Chironomidae): A biomarker for assessment of the heavy metal contaminants in Poland

We studied the effect of heavy metal contaminations on genome instability of Chironomus annularius sensu Strenzke from three sampling sites on the River Chechło valley in southern Poland and a control site in Saraya, Bulgaria. The analysis of the heavy metal concentrations in sediments at the three river sites indicated concentrations higher than those in the fossil reference data (Zn 83-160 times, Pb 64-250 times, and Cd 210-793). According to the geoaccumulation index (Igeo), the sediments at all Chechło stations were classified as extremely polluted (Igeo class 6) by Cd, Pb and Zn while they were much less polluted by Cu (classes 1-3). The concentration of Cd, Pb and Zn in the sediments studied exceeded 21-79, 11-44 and 18-34 times the toxic effect threshold (TET) respectively; therefore, the sediments potentially have detrimental effects on the fauna. Genome instability was determined by somatic structural chromosome alterations (mainly heterozygous inversions) in the salivary gland chromosomes of C. annularius. On the basis of the number and frequency of these aberrations the somatic (S) and cytogenetic (C) indices were calculated as these indices allow a better quantification of the impact of heavy metals on organisms living in sediments. In the three Chechło sampling sites somatic aberrations occurred at a frequency significantly higher than in the control site (P<0.001). The three Chechło samples possess a high spectrum of somatic rearrangements with S index varying from 1.5 to 2.23 while in control site, S is 1.08. The C index of C. annularius from the polluted river sites varied from 0.163 to 0.380, far in excess of the C value of the control site (1.0), indicating strong pollution (<0.5) according to previous studies. In addition, a high level of inherited aberrations was detected (19 inherited band sequences, two of which were new). In all river stations the inverted homozygous band sequences A2.2 occurred in a high frequency (85%) and no standard sequences (A1.1) were observed. The transcription activity of Nucleolar Organizers (NORs) in chromosome arms A, C, E, G was often damaged and NOR activity was completely suppressed in 12.48% of larvae. Moreover, appearance of malformations in the external morphology of larvae was detected in 16.67% of larvae from all polluted sites. Therefore, the genome instability as estimated by two cytogenetic indices is a good biomarker of long-term toxicity and could be successfully implemented in the sediment monitoring procedures. 

Comparison of selected parts of larval morphology in some species of the genus Chironomus (Diptera: Chironomidae) using Scanning Electron Microscope

Comparison of small sized and weakly chitinized structures such as the labrum (labral setae SI-SIII, labral lamella, tormal bar, pecten epipharings) and the maxilla (maxillary palp, lacinial chaeta) is provided in larvae of Chironomus plumosus, C. balatonicus, C. usenicus C. melanotus, C. acerbiphilus, and C. riparius using Scanning Electron Microscope (SEM). The general morphological structures of the labrum and the maxilla were similar in all of the Chironomus larvae. They differed only in fine details such as labral seta, mainly S I. Seta S I is always plumose on each side and differently figured: elongated in C. balatonicus, C. plumosus, C. melanotus and C. usenicus; rounded in C. acerbiphilus and C. riparius. Some differences were also observed in the shape, length or ratio of lacinial chaetae (LCh I, LCh II). Based on morphological variation in the larvae of some Chironomus species, results indicated that the SEM method is apparently beneficial and useful in the analysis of smaller and weakly chitinized morphological structures such as the labrum and the maxilla

Neo- and Paleo-Limnological Studies on Diatom and Cladoceran Communities of Subsidence Ponds Affected by Mine Waters (S. Poland)

Plankton assemblages can be altered to di erent degrees by mining. Here, we test how diatoms and cladocerans in ponds along a river in southern Poland respond to the cessation of the long-term Pb-Zn mining. There are two groups of subsidence ponds in the river valley. One of them (DOWN) was contaminated over a period of mining, which ceased in 2009, whereas the other (UP) appeared after the mining had stopped. We used diatoms and cladocerans (complete organisms in plankton and their remains in sediments) to reveal the influence of environmental change on the structure and density of organisms. The water of UP pond was more contaminated by major ions (SO4 2, Cl) and nutrients (NO3 , PO4 3) than the DOWN ponds. Inversely, concentrations of Zn, Cd, Cu and Pb were significantly higher in sediment cores of DOWN ponds in comparison to those in the UP pond. Ponds during mining had higher diversity of diatoms and cladocerans than the pond formed after the mining had stopped. CCA showed that diatom and cladoceran communities related most significantly to concentrations of Pb in sediment cores. Comparison of diatom and cladoceran communities in plankton and sediment suggests significant recovery of assemblages in recent years and reduction of the harmful e ect of mine-originating heavy metals. Some features of ponds such as the rate of water exchange by river flow and the presence of water plants influenced plankton communities more than the content of dissolved heavy metals

Wpływ przepływu i piętrzenia na jakość wody górskiej rzeki Raby (południowa Polska) : badania wieloletnie

Climate change, manifested by long term periods of drought to heavy rainfall, may remarkably modify river flow regimes. We hypothesize that flow prevailing in a given year determines water chemistry of the Carpathian Raba River above and below Dobczyce Reservoir (southern Poland), used for drinking purposes. Based on the mean annual river flow for years 1991-2017, hydrologically dry (HD), hydrologically average (HA) and hydrologically wet (HW) years were distinguished. We found significant differences in the values of most studied physicochemical parameters of river water above and below the reservoir between studied hydrological years (for a period of April‒November). In HD years, the water above the dam had significantly higher temperature and values of conductivity (point pollution source, groundwater inflow), while lower ones of nutrients NO3- and P-tot (diffuse pollution) compared to those in HA and/or HW years. The best GLM models for mean monthly flows above and below the dam include 3-5 factors among which conductivity and NO3 concentration were always present. The reservoir in different ways influences the water chemistry below the dam in HD, HA and HW years. The impact of flow on the water quality in hydrologically varied years is discussed. The obtained results are important for appropriate management in catchment basins of mountain rivers and the protection of dam reservoirs against the eutrophication processes in changing climate and flow regime.Zmiany klimatu, przejawiające się długotrwałymi okresami suszy lub obfitych opadów, mogą znacząco zmienić roczny reżim przepływów. Stawiamy hipotezę, że przepływ dominujący w danym roku determinuje chemizm wody rzeki górskiej. Celem pracy było określenie (1) różnic w chemizmie wody górskiej rzeki pomiędzy latami hydrologicznie suchymi (HD), przeciętnymi (HA) i mokrymi (HW), (2) wpływu zbiornika zaporowego na chemię wody odpływającej rzeki w różnych latach hydrologicznych, (3) parametrów fizyczno-chemicznych związanych ze średnim miesięcznym przepływem wody w latach HD, HA i HW. Badania prowadzono w karpackiej rzece Rabie powyżej i poniżej Zbiornika Dobczyckiego w południowej Polsce. W oparciu o średni roczny przepływ rzeki z wielolecia 1991–2017 wyróżniono lata HD, HA i HW. Przeanalizowano zmiany parametrów fizyczno- chemicznych wody (temperatura, przewodność elektrolityczna, pH, tlen rozpuszczony, nasycenie tlenem, BZT5, biogeny: NO3-, NH4+, P-tot) pobieranych co miesiąc w okresie kwiecień–listopad. Stwierdziliśmy istotne różnice w chemizmie wody rzeki między badanymi latami hydrologicznymi. W latach HD wody powyżej zbiornika miały istotnie wyższą temperaturę i wartości przewodności elektrolitycznej, natomiast niższe wartości biogenów NO3- i P-tot (zanieczyszczenie obszarowe) w porównaniu do lat HA i/lub HW. Zbiornik w różny sposób kształtował skład chemiczny wody rzeki poniżej zapory w latach HD, HA i HW. Najlepsze modele GLM dla średnich miesięcznych przepływów obejmowały 3–5 czynników, wśród których zawsze występowały przewodność elektrolityczna i stężenia NO3-. Uzyskane wyniki mają istotne znaczenie dla właściwego gospodarowania w zlewniach rzek górskich i ochrony zbiorników zaporowych przed procesami eutrofizacji

The Effects of Channelization with Low In-Stream Barriers on Macroinvertebrate Communities of Mountain Rivers

The effects of channelization with low in-stream barriers in mountain rivers on macroinvertebrate communities are still weakly recognised. We aimed to assess the differences in structure and density of benthic macroinvertebrates between two north Carpathian mountain rivers: one channelized with a cascade of concrete sills and the other one with block ramps. Water was collected five times for physicochemical analysis. Macroinvertebrate fauna and fine bottom sediments were collected three times (spring, summer, autumn) from different habitat types: glides, runs, pools and riffles of the estimated channel surface. The in-stream barriers altered the channel gradient and flow velocity, reducing the area of pools and riffles as well as extending the area of glides with slow current velocities, associated with the highest rate of fine sediment deposition. Channel modifications induced a general shift of investigated fluvial systems toward lentic habitat conditions. Macroinvertebrate communities characteristic of slow-flowing rivers and pools became dominant, while those characteristic for the riffles of mountain rivers were confined to only small areas. The studied section of the Por&#281;bianka River channelized with block ramps exhibited greater diversity in the macroinvertebrate community between habitats and significantly higher macroinvertebrate density than the Mszanka River which was channelized with concrete sills

Potential effect of pH on the leaching of heavy metals from sediments of the Carpathian dam reservoirs

Tyt. z nagłówka.Bibliogr. s. 356-357.Eutrophication processes occurring in the Carpathian dam reservoirs (southern Poland) have resulted in a drastic increase of incidences of decrease of pH and oxygen content in near-bottom water, which may affect metal remobilization from the sediment. The study is aimed to determine the buffer capacity and effects of decreasing pH on the remobilization of heavy metals (Cd, Pb, Cu, Zn, Mn and Fe) from sediments of the Dobczycki Reservoir (DR), the Czorsztyński Reservoir (CR), and the Rożnowski Reservoir (RR), the right side tributary of the Vistula River. Buffering capacity and the leaching of heavy metals from sediments accompanied with an increase in acidity were analyzed in 0.00-0.24 M HNO3 solutions. Studied sediments had a high buffer capacity. Buffer capacity of sediments at studied sites of the DR and CR was different due to differences in the composition of sediments. The reservoir sediments had a variable ability to release heavy metals with increasing acidity. At pH ~5 and pH ~3, a considerable leaching of Mn (up to 60% and 85% of the total amount, respectively), Cd (up to 35% and 56% respectively), Pb (up to 25% and 39%), the lower leaching of Cu (up to 18% and 30%) and Zn (up to 14% and 20%), and the lowest leaching of Fe (below 5%) were found. The decrease of pH of the water-sediment system caused by eutrophication processes may affect the mobilization of certain heavy metals (mainly Mn, Cd and Pb) from sediment into the water column of the studied Carpathian reservoirs.Dostępny również w formie drukowanej.KEYWORDS: Carpathian reservoir, sediments, heavy metals, buffer capacity, pH