Monitoring of DNA damage in haemocytes of freshwater mussel Sinanodonta woodiana sampled from the Velika Morava River in Serbia with the comet assay

This study was undertaken to investigate the potential of the freshwater mussel Sinanodonta woodiana for detection of genotoxic pollution of the environment. Study was performed at two sites in the Velika Morava River, from May 2010 to February 2011. The alkaline comet assay on haemocytes was used, and the olive tail moment (OTM) was chosen as a measure of DNA damage. The specimens held on acclimation under controlled laboratory conditions for 10 d were used as a control. Chemical analysis revealed the presence of phosphates and increased concentrations of zinc, copper and nickel at both sites during the entire sampling period. The values of OTM in mussels collected from the environment, significantly correlated with the concentration of zinc (r = 0.6248), temperature (r = 0.7006) and dissolved oxygen (r = 0.7738). Seasonal variations in genotoxic response were observed, with the highest OTM values obtained during summer months. Preliminary results of the in vitro study indicated the effect of water temperature on genotoxic response to zinc and cadmium in S. woodiana suggesting that the presence of genotoxic pollutants during months with lower temperature could be under-estimated. Obtained results indicate that S. woodiana could be a valuable tool for active biomonitoring of aquatic environments and emphasizes the importance of seasonal genotoxic monitoring with this organism.     

Organotin Compounds and Selected Metals in the Marine Environment of Northern Adriatic Sea

The extent of pollution with organotin compounds and Cd, Pb, Ni, Cu, Zn, Cr, Mn, V, Co and Al was investigated in sediments and mussels (Mytilus galloprovincialis) from the Slovenian costal area of the Northern Adriatic Sea. Sampling was performed in Marina Portorož, Dockyard Izola, non exposed area of the Bay of Mesečev zaliv and in Mariculture Sečovlje. Mussels were taken in the summer and winter time, while sediments were collected during the winter sampling. Organotin compounds were determined by gas chromatography—mass spectrometry and metals by flame or electrothermal atomic absorption spectrometry. The accuracies of the analytical procedures were checked by the analysis of standard reference materials CRM 477 mussel tissue and PACS 2 marine sediment (organotin compounds) and SRM 2976 mussel tissue and CRM 320 river sediment (metals). Good agreements between certified and determined values were obtained. Normalization procedure to Al was applied to estimate the anthropogenic inputs of metals in sediments. The analyses of sediments demonstrated moderate pollution with organotin compounds in Marina Portorož and in Dockyard Izola. Concentrations of tributyltin species were higher than those of dibutyltin and monobutyltin. In mussels substantial contamination with tributyltin was observed in Marina Porotrož and Dockyard Izola. The extent of pollution was higher in the winter time. The analysis of metals in sediments exhibited elevated concentrations in Marina Portorož and Dockyard Izola. Data from the normalization procedure indicated the anthropogenic inputs of Cu, Zn and Cr in Marina Portorož and Mn in Bay of Mesečev zaliv and Dockyard Izola. Mussels, as accumulators of pollutants, in general contained higher metal concentrations during winter time in Dockyard Izola.     

Heavy metals and arsenic concentrations in ten fish species from the Šalek lakes (Slovenia): assessment of potential human health risk due to fish consumption

The study, which measured the concentrations of Hg, Pb, Cd, Zn and As in various fish tissues (muscle, gill and liver) of 10 fish species (Abramis brama danubii, Alburnus alburnus alburnus, Barbus meridionalis petenyi, Carassius auratius gibelio, Cyprinus carpio, Lepomis gibossus, Leuciscius cephalus cephalus, Perca fluviatilis fluviatilis, Rutilus rutilus, Scardinus erythrophtlalmus erythrophtlalmus) collected in the Šalek lakes, is the first survey regarding metal concentrations in fish species with samples originating from Slovene lakes, while only a limited number of such studies have been carried out in southeastern Europe. Since these lakes are situated in the close vicinity of the largest Slovene thermal power plant, the study provides an insight into the potential impact of increased levels of metals in the environment as well as an estimate of the contamination of fish tissues with metals. Furthermore, it was possible to compare the results obtained with those from other studies regarding metal levels in freshwater fish species. The mean metal concentrations of different tissues irrespective of species varied in the following ranges: Zn 4.31–199 mg/kg ww, Pb 0.01–0.48 mg/kg ww, As 0.02–0.44 mg/kg ww, Hg <0.01–0.31 mg/kg ww, Cd < 0.01–0.19 mg/kg ww. In general, higher contents of Hg were found in muscles and livers than in gills and higher contents of As in gills and livers than in muscles, respectively. The accumulation of Pb and Zn was most pronounced in gills. The result obtained regarding metal concentrations in fish revealed that the ecosystems of the Šalek lakes are not polluted with Hg and Pb, slightly loaded with As and Cd and moderately polluted with Zn. In addition, the potential human health risk due to fish consumption was assessed. This showed that the estimated weekly intakes for all metals were far below provisional permissible tolerable weekly intakes determined by WHO/FAO. The consumption of fish from the Šalek lakes, therefore, does not pose a risk to human health.     

Optimizing the SO2 total emission control strategy: case study—Bor (Serbia)

Mumbai, a megacity of India, and its adjacent marine environment, though heavily stressed from various anthropogenic interferences, harbor ~146 km² of mangrove cover. Manori creek, in the close vicinity of Mumbai, sustains relatively better mangrove formations. A creek habitat had been evaluated for its biological and environmental characteristics, and is compared with similar but relatively lesser stressed Mandovi estuary (~475 km south of Mumbai). Several evidences of deteriorating environment of Manori creek have been described with respect to Water quality index and various biotic community structures. Water quality index of <55 indicated unacceptable aquatic conditions of Manori creek. Dominance of Avicennia marina and poor abundance and diversity of mangrove and associated biological features indicate highly stressed environment. Dominance of stress-tolerant phytoplankton spp. such as Skeletonema costatum and benthic fauna such as Polychaeta further supported the view. The data presented in the present document would help in developing rational approach towards conservation, protection, and sustainable development of mangrove-dominated creek and estuarine wetlands.     

Simulations of groundwater-surface water interaction and particle movement due to the effect of weir construction in the sub-watershed of the river Labe in the town of Děčín

Steady- and transient-state simulations of groundwater flow and particle movement in the sub-watershed of the river Labe in Dě?ín town was carried out using Visual MODFLOW software. The simulations were performed for calibration and for the scenarios that the change in the water level of the river Labe was undergoing. Steady-state simulation was carried out for the sake of calibration of model outputs. For transient simulation, two different scenarios were considered in order to investigate the response of the aquifer system to the stresses applied on surface water of the river. The simulation results have shown that the surface water and groundwater interactions, and the subsequent particle movement were affected by the stresses applied on the surface water in the river Labe. The first scenario involved the rapid recharge of surface water to the aquifer in the vicinity of the river while particles still move towards the river at the places far away from the river. At the end of the second scenario, particles still tend to move towards the river slowly and finally tend to stay within the aquifer as equilibrium of hydraulic gradient is reached between the surface and groundwater levels. The time series graphs of hydraulic heads at all observation wells show that the groundwater level in the surrounding aquifer rises significantly as a result of recharges from the river. The local water balance of the study area was calculated and expressed as the rates of water entering and leaving the system. At the end of the second scenario, the difference between the rate of flow into and out of the model area was 0.73 m³ day^?1.     

Genotoxic effects of water pollution on two fish species living in Karasu River,Erzurum, Turkey

Karasu River, which is the only river in the Erzurum plain, is the source of the Euphrates River (Eastern Anatolia of Turkey). The river is in a serious environmental situation as a result of pollution by agricultural and industrial sewage and domestic discharges. The present study aims to evaluate genotoxic effects of toxic metals in chub, Leuciscus cephalus, and transcaucasian barb, Capoeta capoeta, collected from contaminated site of the Karasu River, in comparison with fish from an unpolluted reference site. Heavy metal concentrations in surface water of the river were determined. The condition factor (CF) was taken as a general biomarker of the health of the fish, and genotoxicity assays such as micronucleus (MN) and other nuclear abnormalities (NA) were carried out on the fish species studied. MN and NA such as kidney-shaped nucleus, notched nucleus, binucleated, lobed nucleus, and blebbed nucleus were assessed in peripheral blood erythrocytes, gill epithelial cells, and liver cells of the fish. A significant decrease in CF values associated with a significant elevation in MN and NA frequencies was observed in fish collected from the polluted sites compared with those from the reference site. Results of the current study show the significance of integrating a set of biomarkers to identify the effects of anthropogenic pollution. High concentrations of heavy metals have a potential genotoxic effects, and the toxicity is possibly related to industrial, agricultural, and domestic activities.     

Evaluating Spatio-temporal Complexities of Forest Management: An Integrated Agent-based Modeling and GIS Approach

The objective of this study is to integrate agent-based modeling and geographic information systems (GIS) for examining how interactions within forest management lead to patterns of land-cover change. Specifically, this study evaluates how management agents behave in the presence of variable timber prices, harvesting costs, and accessibility to timber and how their actions influence the spatial characteristics of the forest landscape over time. The GIS calculates the average harvested patch size, number of patches, and total harvested area as measures of emergent patterns resulting from agent actions. The results from the agent-based GIS model reveal that good economic conditions lead to few but large harvested patches, while deteriorating conditions will see more patches of smaller size if forest companies have access to high-quality timber. This study emphasizes the need for a complex systems approach to forest management as the model illustrates how system elements interact in a manner to produce emergent spatial patterns over time.     

Mobilization of aluminum by the acid percolates within unsaturated zone of sandstones

The area of the Black Triangle has been exposed to extreme levels of acid deposition in the twentieth century. The chemical weathering of sandstones found within the Black Triangle became well-known phenomenon. Infiltration of acid rain solutions into the sandstone represents the main input of salt components into the sandstone. The infiltrated solutions–sandstone percolates–react with sandstone matrix and previously deposited materials such as salt efflorescence. Acidic sandstone percolates pH?3.2–4.8 found at ten sites within the National Park Bohemian Switzerland contained high Al-tot (0.8–10 mg?L^?1) concentrations and high concentrations of anions SO₄ (5–66 mg?L^?1) and NO₃ (2–42 mg?L^?1). A high proportion (50–98 %) of Al-tot concentration in acid percolates was represented by toxic reactive Alⁿ⁺. Chemical equilibrium modeling indicated as the most abundant Al species Al³⁺, AlSO₄ ⁺, and AlF²⁺. The remaining 2–50 % of Al-tot concentration was present in the form of complexes with dissolved organic matter Al-org. Mobilization and transport of Al from the upper zones of sandstone causes chemical weathering and sandstone structure deterioration. The most acidic percolates contained the highest concentrations of dissolved organic material (estimated up to 42 mg?L^?1) suggesting the contribution of vegetation on sandstone weathering processes. Very low concentrations of Al-tot in springs at BSNP suggest that Al mobilized in unsaturated zone is transported deeper into the sandstone. This process of mobilization could represent a threat for the water quality small-perched aquifers.     

Assessment of heavy metal levels in sediment samples of Kapulukaya Dam Lake (Kirikkale) and lower catchment area

In this study, the concentrations of 13 elements (Al, Fe, Mn, Cr, Ni, Zn, Co, As, Pb, Cu, Mo, Hg, and Cd) were determined in the sediments of three different sites in the Kapulukaya Dam Lake between May 2007 and November 2008. They ranged from 1.47 to 4.64 for Al, 0.92 to 3.48 for Fe (in percent), 326.60 to 1053.00 for Mn, 98.00 to 1,116.00 for Cr, 24.70 to 127.10 for Ni, 14.80 to 124.20 for Zn, 11.0 to 43.20 for Co, 5.00 to 29.30 for Cu, 9.10 to 69.70 for As, 8.60 to 34.00 for Pb, 2.50 to 5.20 for Mo, 1.00 to 1.60 for Hg, and 0.50 to1.80 for Cd in microgram per gram dry weight sediment. The contamination degree of the sediment was assessed on the basis of enrichment factor and corresponding sediment quality guideline. The calculated enrichment factors (EF, measured metal vs. background concentrations) indicated that the effect of man-made activities on the occurrence of concentrations could be accounted for the majority of heavy metals namely Mn, As, Ni, Cu, Zn, Cr, Co, Mo, and Cd, whereas such affect was not detected for Hg and Pb. The maximum values of the EF were represented by As, minimum values by Hg at all sites. Mean EF values were 36.60 and 0.70 for As and Hg, respectively. This study has clearly assessed a certain level of heavy metal pollution in the region, based particularly on the findings from sediment.