Chalcophile elements Hg, Cd, Pb, As in Lake Umbozero, Murmansk Region, Russia

ABSTRACT: Investigations of Lake Umbozero, the second largest and the deepest lake of the Murmansk Region, were carried out to detect and define biogeochemical patterns of distribution of the chalcophile elements (Hg, Cd, Pb, As) in water, sediments and organs and tissues of whitefishes. Lake Umbozero is affected by emissions and effluents from mining and metallurgical enterprises of the Murmansk Region, as well as air pollution of a global character. Surface and near-bottom maxima were found in the distributions of Pb and Cd in the water column. These two maxima appear to be associated with the cyclical growth of phytoplankton in surface water layers and with sedimentation of lifeless organisms and suspended particles in near-bottom layers. Average concentrations of Pb and Cd in the water column were more than the average value for water of lakes of the taiga zone. Pollution of Lake Umbozero led to higher concentrations of heavy metals in upper layers of sediments as compared to deeper layers. Among heavy metals, the highest factors of contamination were found for Cd and Pb. Pollution of the lake by chalcophile elements has also resulted in their accumulation in organs and tissues of whitefish. Values for concentration factors greater than unity were found for Cd in kidney (5.8) and for Hg in kidney, liver and muscle (3.6, 3.3 and 2.2, respectively) of whitefish

Chironomid fauna of the lakes from the Pechora river basin (east of European part of Russian Arctic): Ecology and reconstruction of recent ecological changes in the region

© 2017, Pleiades Publishing, Ltd. We investigated chironomid fauna of surface sediments and a short sediment core (Bol’shoy Kharbey Lake) from Pechora river basin, Northern Russia. Twenty three investigated lakes have thermokarst, glacial or floodplain origin and are characterised by low mineralization, mostly hydrocarbon-calcium type of water and low concentration of nutrients. Most of the lakes have circumneutral pH around ≤7 and only two lakes are slightly more acidic with pH ≤ 6. Ninety six chironomid taxa were identified in the surface sediments. Distribution of chironomids in the studied region is driven by continentality, mean T July and рН. Chironomid communities from the core of the B. Kharbei Lake demonstrate the highest similarity with the fauna of the deeper lakes of the glacial origin. The glacial lakes have the highest indices of continentality and the lowest winter temperatures within the investigated data set. The chironomid fauna of the glacial lakes is composed of the profundal, oligotrophic and cold-stenotherm taxa. The fauna of the floodplain and thermokarst lakes is more closely related to T July and is composed of littoral and phytophilic taxa of meso–or eutrophic waters and moderate temperature conditions. The fauna of the acidic thermokarst lakes considerably differs from the other lakes. Chironomid communities here are represented by tolerant to acidification taxa, and by the typically littoral and shallow water acid-tolerant taxa that apparently also can tolerate acidification. Studied sediment record covers ca last 200 years. The reconstructed T July during the entire period remain slightly below the modern temperatures. From 1970 reconstructed T July shows steady increase to the modern level. The reconstructed water depths (WDs) of the lake are higher than today till 1980. The highest WDs are reconstructed for ca 1970. After that the WDs gradually decrease to the modern level. Changes of the WDs are most probably related to changes in the precipitation rate

Lakes hydrochemistry in the zone of influence of iron-mining industry waste waters

To assess the current ecological state, a study has been conducted on the chemical composition of the lakes' waters which to varying degrees are influenced by the effluents of Olkon JSC (the town of Olenegorsk, the Murmansk region) mined and processed iron ores. The composition of the water of nearby reservoirs has undergone significant changes with the beginning of the activities of Olkon JSC. Mineralization (up to 100 mg/l) and pH values (up to 7.6) of the water of the studied lakes have increased. The qualitative composition of the water of these lakes also changed – the water class has changed from bicarbonate to sulphate. The biotites that make up the gneisses to which the ore bodies of ferruginous quartzites are confined are the main sources of cations K+ and Mg2+, and amphiboles – Ca2+ and Na+. Therefore, the increase in the content of basic ions and the mineralization of lake water is caused by the inflow of filtration water from tailing and waste dumps of Olkon JSC. The advanced content of the nitrogen group compounds (nitrate ion, ammonium ion and total nitrogen) has been recorded in the lakes' water. This increase is associated with the use of explosives containing nitrogen compounds during drilling and blasting operations for the extraction of iron ores. The content of NO3– in water of some lakes is higher than the content of the basic ions Na+, K+, Cl– in terms of equivalent concentrate ion. The flow of pollutants in the composition of wastewater has led to the suppression of biological activity and a decrease in the content of organic matter in the lake water. The highest levels of Ni, Cu, Co, Al, and Sr are recorded in lakes that receive iron ore production effluent. At the same time Fe concentrations are the smallest, which is associated with the pH value increase in the lake water (which decreases the solubility of Fe ions), and with the decrease in the content of organic material, as far as Fe in the lake waters of the Murmansk region is found mainly in the composition of organo-mineral compound

Distribution of background contents of elements in sediments of Lake Imandra

The background contents of the elements in the sediments of the largest lake of the Murmansk region – Imandra – have been investigated. The background concentrations values of the elements have been determined in the deepest parts of the collected sediment cores. The sedimentation rate in the lakes of North Fennoscandia, including the Murmansk region, is on average 1 mm per year, and the range is between 0.3 and 3 mm/year. The collection of sediment cores 20–25 cm long has been carried out during the study of Lake Imandra. Industrial development of unique deposits of sulfide and apatite-nepheline ores on the watershed of Lake Imandra started in the early 30s of the last century. Consequently, the natural background element contents are fixed in the lower layers of the collected sediment cores. Two groups of elements have been identified by the mathematical statistics methods (correlation and factor analysis): the first group is heavy metals, the second group is alkaline (Na and K) and alkaline-earth metals (Ca, Mg and Sr), Al and P. These elements are in elevated contents in the rock-forming minerals on the catchment area of Lake Imandra: the first group is in the northern part of the catchment area (sulfide copper-nickel ores of Monche Tundra), the second group is in the southeastern part of the catchment area (apatite-nepheline deposits of the Khibiny Alkaline Massif). The largest average background contents of heavy metals (except Co, Pb and As) are noted in the northern part of the Bolshaya Imandra; Ca, Na, Sr, Al and P – in the southern part of the Bolshaya Imandra; Mn – in the Yokostrovskaya Imandra, and Fe – in the Babinskaya Imandra, which is associated with specific conditions for the formation of oxides and hydroxides of these metals in the sediments. The highest background contents of K and Mg are noted in the Babinskaya Imandra, which may be due to the wide distribution of clay minerals with a high content of these metals

The long-term dynamics of hydrochemical indices of low-mineralized subarctic lakes in reducing the acid load

The results of long-term studies (1990–2013) of dynamics of the main hydrochemical indices of the subarctic Shuonijavr Lake located in the zone of airborne pollution from a metallurgical plant have been considered. The following facts have been revealed: significant increase of alkalinity and acid neutralizing capacity (ANC) of the lake water; reduction in the range of seasonal fluctuations of ph and alkalinity; reduction of in the lake water during the observation period as a result of reducing the acid load due to the decrease of SO2 emission. Despite the stabilization of the lake water ANC the pollution indicators in six elements of polluters foreground for the region remain high value

Chalcophile elements Hg, Cd, Pb, As in Lake Umbozero, Murmansk Region, Russia

Investigations of Lake Umbozero, the second largest and the deepest lake of the Murmansk Region, were carried out to detect and define biogeochemical patterns of distribution of the chalcophile elements (Hg, Cd, Pb, As) in water, sediments and organs and tissues of whitefishes. Lake Umbozero is affected by emissions and effluents from mining and metallurgical enterprises of the Murmansk Region, as well as air pollution of a global character. Surface and near-bottom maxima were found in the distributions of Pb and Cd in the water column. These two maxima appear to be associated with the cyclical growth of phytoplankton in surface water layers and with sedimentation of lifeless organisms and suspended particles in near-bottom layers. Average concentrations of Pb and Cd in the water column were more than the average value for water of lakes of the taiga zone. Pollution of Lake Umbozero led to higher concentrations of heavy metals in upper layers of sediments as compared to deeper layers. Among heavy metals, the highest factors of contamination were found for Cd and Pb. Pollution of the lake by chalcophile elements has also resulted in their accumulation in organs and tissues of whitefish. Values for concentration factors greater than unity were found for Cd in kidney (5.8) and for Hg in kidney, liver and muscle (3.6, 3.3 and 2.2, respectively) of whitefish

Trace metal pollution in Eastern Finnmark, Norway and Kola Peninsula, Northwestern Russia as evidenced by studies of lake sediment

Piston sediment cores from Lakes Hundvatn (eastern Finnmark, Norway) and Shuonijârvi (northwestern Russia) in March 1993 were dated with 210 Pb. Sedimentation rates at Hundvatn are 1.9+0.3 mg cm² y1 (0.028 cm y1) below a sediment depth of 4.0 cm and 4.0 mg cm² y 1 above in Shuonijârvi the rate is 2.4 mg cm² y 1 (0.032 cm y 1) over the last 170 years. Cs isotopes from thermonuclear bomb fallout have been redistributed through the core, rendering them useless for dating using 137 Cs. 134 Cs (from Chernobyl) was detected in Shuonijârvi sediment. 241 Am distribution in the sediment is consistent with the 210 Pb chronology. Concentrations and fluxes of Cd, Co, Cu, Ni, Pb, and Zn increase within the last century. All the fluxes except that of Pb are higher to the northeast of the Nikel and, in combination with data from Dauvalter (1994), indicate that smelters of the Pechenga-Nikel Company have been a major source of metal pollution since their start-up and the effects are at a maximum in the youngest sediment, representing approximately the last ten years of sedimentation (up to 1993). No regional pollution of the metals (except Pb) is evident in sediment prior to the 20th century. However, the histories of Pb fluxes and concentrations indicate a pollution history probably in excess of 2000 years