Galina Kashulina

Comparison of the element composition in several plant species and their substrate from a 1 500 000-km2 area in Northern Europe

Leaves of 9 different plant species (terrestrial moss represented by: Hylocomium splendens and Pleurozium schreberi; and 7 species of vascular plants: blueberry, Vaccinium myrtillus; cowberry, Vaccinium titis-idaea; crowberry, Empetrum nigrum; birch, Betula pubescens; willow, Salix spp.; pine, Pinus sylvestris and spruce, Picea abies) have been collected from up to 9 catchments (size 14-50 km2) spread over a 1500000 km2 area in Northern Europe. Soil samples were taken of the O-horizon and of the C-horizon at each plant sample site. All samples were analysed for 38 elements (Ag, Al, As, B, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Rb, S, Sb, Sc, Se, Si, Sn, Sr, Th, Tl, U, V, Y, Zn and Zr) by ICP-MS, ICP-AES or CV-AAS (for Hg-analysis) techniques. The concentrations of some elements vary significantly between different plants (e.g. Cd, V, Co, Pb, Ba and Y). Other elements show surprisingly similar levels in all plants (e.g. Rb, S, Cu, K, Ca, P and Mg). Each group of plants (moss, shrubs, deciduous and conifers) shows a common behaviour for some elements. Each plant accumulates or excludes some selected elements. Compared to the C-horizon, a number of elements (S, K, B, Ca, P and Mn) are clearly enriched in plants. Elements showing very low plant/C-horizon ratios (e.g. Zr, Th, U, Y, Fe, Li and Al) can be used as an indicator of minerogenic dust. The plant/O-horizon and O-horizon/C-horizon ratios show that some elements are accumulated in the O-horizon (e.g. Pb, Bi, As, Ag, Sb). Airborne organic material attached to the leaves can thus, result in high values of these elements without any pollution source.

Multi-element, multi-medium regional geochemistry in the European Arctic: element concentration, variation and correlation

Abstract A multi-medium, multi element regional geochemical survey has been carried out in an 188,000 km 2 area in the Central Barents Region, Finland, Norway and Russia. Four different sample materials (terrestrial moss, O-, B- and C-horizons of podzol) were collected at the same sites throughout the area at a density of 1 site/300 km 2 . While moss predominantly reflects the atmospheric input of elements, the O-horizon reflects the complex interplay between atmosphere, biosphere and lithosphere. The B-horizon can be used to study the influence of soil-forming processes, while the C-horizon represents the composition of the lithosphere at each sample site and thus the geogenic background. The concentration, variation and correlation between 24 elements (Ag, Al, As, Ba, Bi, Ca, Cd, Co, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, S, Si, Sr, Th, V, Zn) analysed with similar techniques in all 4 materials are compared. Some rare trace elements (Ag, As, Bi, Cd, Pb) appear to be considerably more enriched in the O-horizon of podzols than the main pollutants in the survey area (Ni, Cu, Co from the Russian nickel industry in Monchegorsk and Nikel-Zapoljarnij). Biological processes play an underestimated role in determining regional geochemistry at the earths surface.

Influence of extreme pollution on the inorganic chemical composition of some plants

Leaves of nine different plant species (terrestrial moss: Hylocomium splendens and Pleurozium schreberi, blueberry: Vaccinium myrtillus, cowberry: Vaccinium vitis-idaea, crowberry: Empetrum nigrum, birch: Betula pubescens, willow: Salix spp., pine: Pinus sylvestris, and spruce: Picea abies) have been collected from up to nine catchments (size 14-50 km2) spread over a 1,500,000 km2 area in northern Europe. Additional soil samples were taken from the O-horizon and the C-horizon at each plant sample site. All samples were analysed for 38 elements (Ag, Al, As, B, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Rb, S, Sb, Sc, Se, Si, Sn, Sr, Th, Tl, U, V, Y, Zn, and Zr) by ICP-MS, ICP-AES or CV-AAS (Hg) techniques. One of the 9 catchments was located directly adjacent (5-10 km S) to the nickel smelter and refinery at Monchegorsk, Kola Peninsula, Russia. The high levels of pollution at this site are reflected in the chemical composition of all plant leaves. However, it appears that each plant enriches (or excludes) different elements. Elements emitted at trace levels, such as Ag, As and Bi, are relatively much more enriched in most plants than the major pollutants Ni, Cu and Co. The very high levels of SO2 emissions are generally not reflected by increases in plant total S-content. Several important macro-(P) and micro-nutrients (Mn, Mg, and Zn) are depleted in most plant leaves collected near Monchegorsk.

Seasonal variability of total and easily leachable element contents in topsoils (0–5 cm) from eight catchments in the European Arctic (Finland, Norway and Russia)

Frozen topsoil samples (0-5 cm) were collected during March/April 1994 in eight Arctic catchments in northern Europe (4 in Russia, 3 in Finland, 1 in Norway) at varying distances and wind directions from the emissions of the Russian nickel ore mining, roasting and smelting industry on the Kola Peninsula. Between 14 and 25 sites were sampled in catchment basins ranging in size from 12 to 35 km(2). Sampling was repeated in spring immediately after the snow melted, in summer and in autumn to study seasonal variability and the fate of elements when the snow melts. The <2 mm fraction of air-dried topsoils was analysed for total (aqua regia extraction) and easily leachable (in 1 m ammonium acetate, buffered at pH 4.5) element concentrations using ICP-AES and GFAAS for up to 35 elements. Results for selected elements are presented here. Soil organic matter can be shown to be the controlling factor determining element contents and fate. In catchments close to the Russian nickel industry, the topsoils have low carbon and nitrogen contents. Using both extraction methods most elements reach maximum concentrations in winter; lowest concentrations are observed in midsummer. Soil organic matter and elements associated with it are thus leached out of the soils together with soluble elements when the snow melts. This process continues in summer. Elements will enrich surface waters, the lower layers of podzol profiles, or reach the groundwater. The use of the two extractions described provides a simple method to study the mobilities and pathways of elements in the topsoils during the arctic year. Using the proportions of easily leachable to total concentration, a good estimation of the status of the topsoil in the study area can be given.

Reliability of moss (Hylocomium splendens and Pleurozium schreberi) as a bioindicator of atmospheric chemistry in the Barents region: Interspecies and field duplicate variability

As part of a collaborative ecogeochemical mapping project in the European Arctic, the terrestrial mosses Hylocomium splendens (Hs) and Pleurozium schreberi (Pl) have been used to document atmospheric chemistry. The regional importance of the variability of interspecies and field duplicate samples on the element distribution in the central Barents region has been calculated. Of the 36 elements studied, 17 have significantly different concentrations in the two species. Except for K, in which all Pl samples are significantly enriched compared to Hs samples, all elements showed at least one pair that displayed the opposite behaviour to the overall trend. For the regional data set of the central Barents region, the interspecies results for (B), Bi, Cd, Co, Fe, Mn, (Na), Ni, P, Pb, S, Si, Sr, Th, U, V and Zn are directly comparable without calibration, due to lack of significant interspecies differences or a higher field duplicate uncertainty. The regional distribution of Ag, Ba, Hg, K and Sb must be interpreted cautiously in background areas, since these elements lack interspecies correlation and show significant differences between the species. Furthermore, calibration may be advisable for Al, As, Co, Cr, Cu, Fe, Mo, Tl and V for which the interspecies ratio (Pl:Hs) varies from 0.56 to 0.91, and Ca, Cd, Mg, Pb and Rb for which the ratio varies from 1.10 to 1.38. However, as a result of our study we recommend that the original data be used without undertaking calibration, but interspecies ratios need to be quantified in all multispecies datasets. Calibrated maps of the latter elements gave no striking changes in the patterns, and a new uncertainty is introduced by calibrating the original data sets. Striking differences between interspecies ratios from six comparable studies are found, especially for As, Ni, Pb and V, which underline the fact that interspecies variations depend greatly on deposition levels and living conditions for the moss.

Regional atmospheric deposition patterns of Ag, As, Bi, Cd, Hg, Mo, Sb and Tl in a 188,000 km2 area in the European arctic as displayed by terrestrial moss samples-long-range atmospheric transport vs local impact

Abstract The regional atmospheric deposition patterns of Ag, As, Bi, Cd, Hg, Mo, Sb and Tl have been mapped in a 188,000 km2 area of the European Arctic (N Finland, N Norway, NW Russia) using the moss technique. The Russian nickel mining and smelting industry (Nikel and Zapoljarnij (Pechenganikel) and Monchegorsk (Severonikel)) in the eastern part of the survey area represents two of the largest point sources for S02 and metal emissions on a world wide basis. In contrast, parts of northern Finland and northern Norway represent still some of the most pristine areas in Europe. The terrestrial mosses Hylocomium splendens and Pleurozium schreberi were used as monitors of airborne deposition. Samples in all three countries were collected during the summer of 1995 and analysed in one laboratory using ICP-MS. Maps for most elements clearly show elevated element concentrations near the industrial sites and delineate the extent of contamination. Pollution follows the main wind and topographical directions in the area (N-S). The gradients of deposition are rather steep. Background levels for all the elements are reached within 150–200 km from the industrial plants. The relative importance of long-range atmospheric transport of air pollutants from industrial point sources on the world wide increase of heavy metals observed in the atmosphere is thus debatable for many elements. Increasing population and traffic density, accompanied by increasing local dust levels, may play a much more important role than industrial emissions. The regional distribution patterns as displayed in the maps show some striking differences between the elements. The regional distribution of Hg and TI in the survey area is completely dominated by sources other than industry.

Regional patterns of heavy metals (Co, Cr, Cu, Fe, Ni, Pb, V and Zn) and sulphur in terrestrial moss samples as indication of airborne pollution in a 188, 000 km2 area in northern Finland, Norway and Russia

The geological surveys of Finland and Norway and the Central Kola Expedition in Russia are carrying out a geochemical mapping project in a 188,000 km2 area north of the Arctic Circle. Several sample media (terrestrial moss, organic topsoil (0–3 cm), topsoil (0–5 cm), complete podzol profiles) were collected throughout the area during the summer of 1995 at an average density of one sample station per 300 km2. Colour surface maps of the major airborne pollutants (Ni, Cu, Co and S) from the Russian nickel mining and smelting industry in this area, as recorded by ICP—MS and ICP—AES analysis of terrestrial mosses, clearly show the industrial sites and the areal extent of the pollution. The contrast between background and polluted sites is very large for Ni, Cu and Co, but not for S. Pollution follows the main wind and topographical directions in the area, and gradients towards the west are rather steep. Maps for some additional elements (Fe, Cr, Pb, V, Zn) show the influence of other sources than just airborne pollution on the composition of the mosses. Zn is an example of an element whose local variation is so high that no reliable regional maps can be constructed using the moss technique. A hitherto unknown, large V anomaly was detected in the surroundings of Murmansk.

The state of the ecosystems in the central Barents Region: scale, factors and mechanism of disturbance

Abstract More than 650 locations spread over a 188000-km2 area in the European Arctic (Russia, Finland and Norway) were visited in the course of an ecogeochemical mapping project during 1995. Moss and soil samples were taken for chemical analyses and each site was documented in a series of photographs. The qualitative, empirical data gained during the project shows that the ecosystem is damaged over vast areas. The scale of the damage, as well as its causes, vary from country to country. Industrial activity, including two of the worlds largest SO2 and heavy-metal emission sources on the Kola Peninsula, is responsible for almost all of the pollution and visual ecosystem damage found in the Russian project area. In the Finnish and Norwegian areas, reindeer overgrazing is the major cause of ecosystem damage. The scale of the damage from overgrazing in Finland is comparable to, and in Norway even more extensive than, the industry-related damage found in Russia. Comparison of the two different factors involving human impact (pollution and overgrazing) on a delicate ecosystem provides new information on the mechanisms of ecosystem degradation.

Processes influencing the chemical composition of the O-horizon of podzols along a 500-km north-south profile from the coast of the Barents Sea to the Arctic Circle.

Abstract Large-scale regional processes influencing the chemical composition of the O-horizon of podzols have been studied along a 500-km-long north–south profile from the coast of the Barents Sea in N-Norway (North Cape) to the Arctic Circle in northern Finland. Precipitation (composition and amount) appears to be the major factor determining the chemical composition of the O-horizon, followed by vegetation (especially the change from the tundra and subarctic birch forest to the boreal forest zone). This results in distance to coast having an important influence on pH and concentrations and fluxes of over 20 elements in the O-horizon along this profile. A high local variability of several elements, especially some important nutrients, indicates that other small-scale processes also play an important role. While there are signs that elements displaced from surficial soils accumulate in the C-horizon, the composition of the soil parent material (bedrock, Quaternary drift) has relatively little influence on the chemistry of the O-horizon for most elements.

Comparison of plant and precipitation chemistry in catchments with different levels of pollution on the Kola Peninsula, Russia

Highly variable concentration patterns for up to 29 elements were found in three plant-groups (crowberry — Empetrum nigrum; lichen — Cladonia sp.; and terrestrial moss — Hylocomium splendens+Pleurozium schreberi) collected in selected catchments in the central Barents region. Element concentrations in the plants are compared with those observed for rain, snow melt water and snow filter residue collected in the same catchments. Based on these results the suitability of each plant-group as a bio-indicator for atmospheric input of elements is evaluated. Lichen shows by far the lowest concentrations in most major elements (Ca, S, P, Al, Mg, Mn and Fe). The highest levels of Cr, Fe, Mg, and S appear in all three plant-groups near the nickel roaster in Zapoljarnij. In moss and lichen, Ag, Ba, Bi, Cd, and Na show the highest concentration within the impact zone of the nickel refinery in Monchegorsk. However, these plants do not survive in the immediate vicinity of this refinery where concentrations of As, Co, Cu, Mo, Ni and Pb in crowberry are higher than for all other vegetation samples in our study. The three groups react quite different to dust input (e.g. Al, Ba, Ca, K, La, Na, P, Rb, Sr and Y) from the large open cast apatite mine in Kirovsk near Apatity. For a large number of elements all three groups mirror at least a part of the elemental input via precipitation. Each plant-group reflects precipitation chemistry especially well for some elements. Moss reacts most strongly to rain, lichen is probably the best ‘integrator’ and crowberry reflects best the particulate input. Ni is the only element for which all three plant-groups directly reflect the atmospheric input pattern via precipitation. For the other elements the input patterns are often essentially altered. To reliably use plant chemistry for documenting pollution patterns a very large regional contrast in deposition appears to be necessary for most elements.