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1.
Using interdisciplinary field research in the Usa Basin, northeast European Russia, we compared local inhabitants' perception of environmental problems with chemical and remote-sensing signatures of environmental pollution and their local impacts. Extensive coal mining since the 1930s around Inta and Vorkuta has left a legacy of pollution, detected by measuring snowpack, topsoil, and lichen chemistry, together with remote-sensing techniques and analysis of lake water and sediments. Vorkuta and its environs suffered the worst impacts, with significant metal loading and alkalization in lakes and topsoils, elevated metals and cations in terricolous (reindeer) lichens, and changes in vegetation communities. Although the coal industry has declined recently, the area boasts a booming oil and gas industry, based around Usinsk. Local perceptions and concerns of environmental pollution and protection were higher in Usinsk, as a result of increased awareness after a major oil spill in 1994, compared with Vorkuta's inhabitants, who perceived air pollution as the primary environmental threat. Our studies indicate that the principal sources of atmospheric emissions and local deposition within 25 to 40 km of Vorkuta were coal combustion from power and heating plants, coal mines, and a cement factory. Local people evaluated air pollution from direct observations and personal experiences, such as discoloration of snow and respiratory problems, whereas scientific knowledge played a minor role in shaping these perceptions.  相似文献   

2.
Trace metal composition of winter snowpack, snow-melt filter residues and top-soil samples were determined along three transects through industrial towns in the Usa basin, North-East Russia: Inta, Usinsk and Vorkuta. Snow was analysed for Ag, Al, As, Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sr and Zn using ICP-MS (Ca and K by F-AAS for Vorkuta only), pH and acidity/alkalinity. Filter residues were analysed for: Al, Ba, Ca, Cd, Cu, K, Mg, Mn, Ni, Pb, Sr and Zn using F-AAS and GF-AAS; top-soil samples were analysed for Ba, Cu, Mg, Mn, Na, Ni, Pb, Sr, Zn using F-AAS. Results indicate elevated concentrations of elements associated with alkaline combustion ash around the coal mining towns of Vorkuta and Inta. There is little evidence of deposition around the gas and oil town of Usinsk. Atmospheric deposition in the vicinity of Vorkuta, and to a lesser extent Inta, added significantly to the soil contaminant loading as a result of ash fallout. Acid deposition was associated with pristine areas whereas alkaline combustion ash near to emission sources more than compensated for the acidity caused by SO2.  相似文献   

3.
The chemical composition and pH of 30 fresh snow samples collected during December 1986 to May 1987 at Gulmarg (34 degrees 03' N, 74 degrees 24' E, 2655 m above mean sea level), a remote place in north India, were studied. The snow samples were, by and large, alkaline in nature and were largely influenced by non-marine aerosols. The concentrations of cations (Ca(2+), K(+) and Mg(2+)) were more than the anions (SO(2-)(4) and NO(-)(3)). Factor analysis indicated that most of the ionic components were transported into the region during the period of measurements. The transport of ionic components could be attributed to the passage of western disturbances over this region. The comparison of concentrations of anions and cations in the snow samples at Gulmarg with those reported from a few countries in the west revealed that the composition of Gulmarg snow largely differs in the concentrations of cations rather than anions. Among the cations, the concentration of Ca(2+) was high at Gulmarg and this could be responsible for buffering the pH of snow in the alkaline range.  相似文献   

4.
Three-year-old Douglas firs (Pseudotsuga menziesii) were fumigated with 180 microg m(-3) NH3 or clean (charcoal-filtered) air. During these fumigations the plants received 15 mm artificial rain weekly, supplemented with 20, 500 or 2500 micromol litre(-1) (NH4)2SO4. Exposure to NH3 and NH4+ for 14 weeks resulted in a change of the nutrient status of the needles. The most remarkable effect was the increase in the N/K ratio, due to both uptake of N and leaching of K. The action of NH3 was stronger than that of NH4+. Both NH3 and (NH4)2SO4 affected the epicuticular wax layer and decreased mycorhiza frequency. Following fumigation and artificial rain treatments, needles were incubated for 8 h in a medium containing 0, 50, 250, 500 and 2500 micromol litre(-1) (NH4)2SO4. Almost no exchange of Ca, Mg and K for NH4+ was found. Therefore this ion exchange probably explains only a minor part of the changes in nutrient status of the whole trees.  相似文献   

5.
Effects of fluoride (F(-)) emissions on previously unpolluted assemblages of saxicolous lichens, near an aluminium reduction works, are described. Lichens contained a mean 16 microg F(-) g(-1) dry weight in 1970 before emissions commenced. Subsequently, where annually monitored Ramalina contained >100microg g(-1) severe damage occurred, including loss of attachment to the rocky substratum. At sites within 1 km of the works well-exposed to emissions, fruticose (shrubby) lichens were eliminated, but in more sheltered locations 18% cover had survived by 1983. Some foliose (leaf-like) lichens tolerated >200 microg g(-1), while crustose (crust-like) species were least affected, 32% and 70% surviving, respectively. Concentrations of fluoride, and associated injury, decreased with increasing distance from the works. Fruticose and sensitive foliose species sustained 40-75% losses of cover up to 4 km NE, downwind of the works, where fluoride averaged 50-100 microg g(-1), but <40% losses were recorded in fruticose species up to 9 km, where concentrations averaged 35-50 microg. Saxicolous lichens were damaged less than corticolous species previously reported and, following decreased emissions, were also regrowing in sheltered and more distant locations by 1985.  相似文献   

6.
In this paper we present what kind of human impacted changes can be found in dwarf birch (Betula nana) dominated shrub tundra vegetation around the large industrial complex of Vorkuta in the north-European Russian tundra. Using fieldwork data and Landsat TM satellite image we could identify two impact zones: (1) Pollution zone (150-200 km2). In this zone most of the lichen species are absent. Changes in vegetation communities' species composition in all main plant groups are obvious. Willows especially are more dominant than in the unpolluted sites. (2) Slight pollution/disturbance zone (600-900 km2). Here vegetation changes are mainly similar but less so than the changes in the first zone. Particularly, the amount of herbs and grasses is increased when compared to unpolluted areas. The pollution zones are spatially connected to the main emission sources in the area. Zones spread furthest to the northeast, matching the prevailing winds during winter.  相似文献   

7.
Total concentrations of major and trace elements were determined in samples of the epilithic lichen Umbilicaria decussata from 24 ice-free areas in coastal Victoria Land (Antarctica). Overall average concentrations of trace elements except Cd were the lowest ever reported for lichens of the genus Umbilicaria. Specifically, the mean level of Pb in lichens from granitic rocks (0.46 +/- 0.18 microg g(-1) dry wt) was more than four times lower than the lowest record in Arctic lichens. No impact of local human activities was detected, but the elemental composition of U. decussata was affected by entrapment of soil or rock dust particles and probably by uptake of soluble elements from substrate. Relationships between elements and their distribution patterns in the study area indicated that the marine environment is the main source of major ions and perhaps of Cd in lichens. Accumulation of P was detected in samples from coastal sites frequented by seabirds. Although the present results can be taken as baseline levels of major and trace elements in Antarctic U. decussata from substrates with very different geochemical features, further research is necessary to evaluate the relative element contribution from each substrate with respect to those from snow, marine aerosol, salt encrustations and guano.  相似文献   

8.
S Loppi 《Chemosphere》2001,45(6-7):991-995
The environmental distribution of mercury and other trace elements in the geothermal area of Bagnore (Mt. Amiata, central Italy) and its surroundings was evaluated by means of lichens used as bioaccumulators. Adopting a 'before-after' strategy, the impact of a recently built power plant was also evaluated. Four sites were sampled: (1) S. Fiora, a town 2 km SE of Bagnore; (2) Bagnore, a village where geothermal power is generated; (3) Aiole, a locality 1.5 km NW of Bagnore with an abandoned Hg smelting plant and a waste pile of roasted cinnabar; (4) Arcidosso, a town 3.5 km NW of Bagnore. At S. Fiora and Arcidosso, where most of the population is concentrated, mercury levels in lichens were within the background range (0.1-0.2 microg/g dw). On the contrary, at Aiole, Hg concentrations (0.63-0.67 microg/g dw) were much higher than background. After the new geothermal power plant went into operation at Bagnore, lichen concentrations of Hg showed a 50% increase from 0.22 to 0.32 microg/g dw. This value, however, is in line with those found in lichens from natural areas with hot springs and fumaroles.  相似文献   

9.
Spatial variability of ammonium and nitrate in soils near a poultry farm   总被引:1,自引:0,他引:1  
This paper assesses the distribution of ammonium (NH4+) and nitrate (NO3-) nitrogen deposition in native bushland soil adjacent to an open ventilated poultry farm. The farm is located in Thirlmere 150 km south west of Sydney, Australia. A total of 104 geographically referenced soil cores were obtained from the study area. Soil pH, electrical conductivity (EC), NH4(+) - and NO3(-)-nitrogen concentrations were analysed for variable trends at three depths, i.e. 0-30, 30-60, and 60-90 cm. Significantly higher concentrations of the two nitrogen forms and EC were observed nearer to the farm in the surface soil samples (0-30 cm). The distribution of NH4+, NO3- and EC were all correlated in surface samples throughout the study area. There was no indication of NH4+ and NO3- leaching within soil profile sampled and it appears that weeds and native vegetation had utilised the accumulated nitrogen. The level of N deposition adjacent to the poultry farm decreased downwind due to dispersion of plume and to the buffering effects from the bushland.  相似文献   

10.
Denitrification in the river estuaries of the northern Baltic Sea   总被引:3,自引:0,他引:3  
Estuaries have been suggested to have an important role in reducing the nitrogen load transported to the sea. We measured denitrification rates in six estuaries of the northern Baltic Sea. Four of them were river mouths in the Bothnian Bay (northern Gulf of Bothnia), and two were estuary bays, one in the Archipelago Sea (southern Gulf of Bothnia) and the other in the Gulf of Finland. Denitrification rates in the four river mouths varied between 330 and 905 micromol N m(-2) d(-1). The estuary bays at the Archipelago Sea and the Gulf of Bothnia had denitrification rates from 90 micromol N m(-2) d(-1) to 910 micromol N m(-2) d(-1) and from 230 micromol N m(-2) d(-1) to 320 micromol N m(-2) d(-1), respectively. Denitrification removed 3.6-9.0% of the total nitrogen loading in the river mouths and in the estuary bay in the Gulf of Finland, where the residence times were short. In the estuary bay with a long residence time, in the Archipelago Sea, up to 4.5% of nitrate loading and 19% of nitrogen loading were removed before entering the sea. According to our results, the sediments of the fast-flowing rivers and the estuary areas with short residence times have a limited capacity to reduce the nitrogen load to the Baltic Sea.  相似文献   

11.
Effects of emissions, from a new aluminium works, on previously unpolluted assemblages of corticolous lichens, are described. Injury symptoms included chlorosis, red colorations, necrosis and weakening of attachment of thalli to the bark substratum, resulting in reductions in % cover. Before emissions commenced in 1970, lichens contained <10microg fluoride (F(-)) g(-1) dry weight. Where concentrations in annually monitored samples of Ramalina reached >100microg F(-1) g(-1), within 4 km downwind of the works, severe injury occurred with >75% losses of cover of some species. At increasing distances, injury, and F(-) concentrations, decreased. The lichen flora was almost eliminated within 1 km of the works: after 15 years' operation, 37 species are absent within 650 m, but at least 43 survive at 900 m. A range of sensitivity was shown between, and within, morphological types. Fructicose (shrubby) lichens contained >600microg F(-1) g(-1) after 4 years and were the first, and most severely, affected (<1% cover surviving by 1975). Most foliose (leaf-like) species were sensitive (88% losses by 1977), but some were more tolerant, containing >400microg F(-1) g(-1) after 10 years. Crustose (crust-like) lichens were affected least, some growing markedly to occupy the space formed following elimination of more intolerant species. Since 1978, in response to decreasing emissions, there has been a recovery of some fruticose and foliose species in less-exposed locations.  相似文献   

12.
Ecological studies have demonstrated the adverse effects of road-salt, primarily NaCl, on water quality, flora, and fauna. In this study, we quantified changes in ionic composition and solute flux of water draining the Mohawk River Basin (9103 km(2)) in New York State, from 1952 to 1998. Using various statistical, graphical, and modeling techniques, we showed that concentrations ofNa+ and Cl- have increased by 130 and 243%, respectively, while other constituents have decreased or remained constant. The use of de-icing salt on roads within the watershed, which we estimate at 39 kg km(-2) day(-1), appears to be the primary mechanism responsible for reported increases, accounting for the increase in NaCl export from 16 to 46 kg km(-2) day(-1) over the 47-year period.Moreover, despite population decline within this rural upstate watershed, increased environmental stewardship, and The Clean Water Act, concentrations of Na+ and Cl- still increased during the 1990s.  相似文献   

13.
The sulphur isotope composition of the epiphytic lichens, Hypogymnia physodes (L.) Nyl and Pseudevernia furfuracea (L.) Zopf, of the terricolous lichens, Cladina sp. and Peltigera aphthosa (L.) Willd., and of pine bark, at 31 sites in Finland, appeared to be dependent on lichen and tree species. The negative correlation of sulphur isotope composition with sulphur content was highly significant (P<0.001) in H. physodes and significant (P<0.01) in Pseudevernia furfuracea and Peltigera aphthosa. No correlation between the sulphur isotope composition and sulphur content was found for Cladina sp. and pine bark. The sulphur isotope compositions displayed statistically significant regional variation from south to north. Microenvironmental factors were considered, including phorophyte species and the chemical form of sulphur.  相似文献   

14.
On an upland moor dominated by pioneer Calluna vulgaris and with an understorey of mosses and lichens, experimental plots were treated with factorial combinations of nitrogen (N) at +0 and +20kg Nha(-1)yr(-1), and phosphorus (P) at +0 and +5kg Pha(-1)yr(-1). Over the 4-year duration of the experiment, the cover of the Calluna canopy increased in density over time as part of normal phenological development. Moss cover increased initially in response to N addition but then remained static; increases in cover in response to P addition became stronger over time, eventually causing reductions in the cover of the dominant Calluna canopy. Lichen cover virtually disappeared within 4 years in plots receiving +20kg Nha(-1)yr(-1) and also in separate plots receiving +10kg Nha(-1)yr(-1), but this effect was reversed by the addition of P.  相似文献   

15.
Two country-wide surveys using epiphytic lichens as biomonitors of atmospheric pollution carried out during 2000 and 2001 in Slovenia were compared with surveys in 1991 and 1992. In the first survey, epiphytic lichen cover was studied in more than 500 plots of the 4 x 4 km national grid carried out within the framework of forest decline inventories. In the second survey, the epiphytic lichen Hypogymnia physodes (L.) Nyl., was collected on a 16 x 16 km bioindication grid and analysed for S, N, As, Br, Ce, Cd, Cr, K, La, Mo, Rb, Sb, Th, U and Zn contents. Only 'forested area' sampling points were included in the present study. Lichen cover was low, with about 70% of plots with less than 10% foliose lichen cover. No relationship was found between Hypogymnia trace element, N and S concentrations and foliose epiphytic lichen cover.  相似文献   

16.
In April 1996 snowpack samples were collected from the surroundings of the ore roasting and dressing plant at Zapoljarnij and the nickel smelters at Nikel and Monchegorsk, Kola Peninsula, NW Russia. In the laboratory, filter residues of snowpack samples (fraction>0.45 μm) from 15 localities (close to the nickel processing centres) were chemically for precious metals (Rh, Pt, Pd, Au) and Te by graphite furnace atomic absorption spectrometry (GFAAS) analysis, and for Cu and Ni by ICP-MS. Values up to 2770 ng/l Pd, 650 ng/l Pt and 186 ng/l Au were found in the filter residues. Additionally, platinum-group elements (PGE) and Au contents in ore samples from Noril’sk1, as well as in technogenic products (“Cu–Ni-feinstein” and copper concentrate) processed at the Monchegorsk smelter complex, were analysed using flameless atomic absorption spectroscopy (FAAS) for comparison with results obtained from snow. Rh, Pt, Pd and Au distribution data show the presence of two ore components (Noril’sk and Pechenga). Concentrations of these metals decrease with distance from the industrial sources and with the prevailing wind direction (generally north–south). Microscopic investigations and electron microprobe analysis of polished sections of snow filter residues (>0.45 μm) also reveal differences between particles from the two sources.  相似文献   

17.
Effects of atmospheric ammonia (NH3) on terrestrial vegetation: a review   总被引:17,自引:0,他引:17  
At the global scale, among all N (nitrogen) species in the atmosphere and their deposition on to terrestrial vegetation and other receptors, NH3 (ammonia) is considered to be the foremost. The major sources for atmospheric NH3 are agricultural activities and animal feedlot operations, followed by biomass burning (including forest fires) and to a lesser extent fossil fuel combustion. Close to its sources, acute exposures to NH3 can result in visible foliar injury on vegetation. NH3 is deposited rapidly within the first 4-5 km from its source. However, NH3 is also converted in the atmosphere to fine particle NH4+ (ammonium) aerosols that are a regional scale problem. Much of our current knowledge of the effects of NH3 on higher plants is predominantly derived from studies conducted in Europe. Adverse effects on vegetation occur when the rate of foliar uptake of NH3 is greater than the rate and capacity for in vivo detoxification by the plants. Most to least sensitive plant species to NH3 are native vegetation > forests > agricultural crops. There are also a number of studies on N deposition and lichens, mosses and green algae. Direct cause and effect relationships in most of those cases (exceptions being those locations very close to point sources) are confounded by other environmental factors, particularly changes in the ambient SO2 (sulfur dioxide) concentrations. In addition to direct foliar injury, adverse effects of NH3 on higher plants include alterations in: growth and productivity, tissue content of nutrients and toxic elements, drought and frost tolerance, responses to insect pests and disease causing microorganisms (pathogens), development of beneficial root symbiotic or mycorrhizal associations and inter species competition or biodiversity. In all these cases, the joint effects of NH3 with other air pollutants such as all-pervasive O3 or increasing CO2 concentrations are poorly understood. While NH3 uptake in higher plants occurs through the shoots, NH4+ uptake occurs through the shoots, roots and through both pathways. However, NH4+ is immobile in the soil and is converted to NO3- (nitrate). In agricultural systems, additions of NO3- to the soil (initially as NH3 or NH4+) and the consequent increases in the emissions of N2O (nitrous oxide, a greenhouse gas) and leaching of NO3- into the ground and surface waters are of major environmental concern. At the ecosystem level NH3 deposition cannot be viewed alone, but in the context of total N deposition. There are a number of forest ecosystems in North America that have been subjected to N saturation and the consequent negative effects. There are also heathlands and other plant communities in Europe that have been subjected to N-induced alterations. Regulatory mitigative approaches to these problems include the use of N saturation data or the concept of critical loads. Current information suggests that a critical load of 5-10 kg ha(-1) year(-1) of total N deposition (both dry and wet deposition combined of all atmospheric N species) would protect the most vulnerable terrestrial ecosystems (heaths, bogs, cryptogams) and values of 10-20 kg ha(-1) year(-1) would protect forests, depending on soil conditions. However, to derive the best analysis, the critical load concept should be coupled to the results and consequences of N saturation.  相似文献   

18.
This study aimed at investigating the cellular distribution of Hg in the lichens Cladonia arbuscula subsp. mitis and Peltigera rufescens treated with Hg2+ and at testing if Hg treatment affects selected physiological parameters. In both species, increasing Hg accumulation under increasing Hg supply in the treatment solutions was found. P. rufescens showed a higher intracellular accumulation. Photosynthetic parameters were negatively affected in both species, as indicated by the decrease in photosynthetic pigments content, photosynthetic efficiency and chlorophyll integrity. Cell membranes of both species endured damage as indicated by the increase in the concentration of products of lipid peroxidation and decrease in ergosterol content. Nevertheless, differences between the two species were found, suggesting a differential sensitivity to Hg.  相似文献   

19.
The concept of critical levels was developed in order to define short-term and long-term average concentrations of gaseous pollutants above which plants may be damaged. Although the usual way in which pollutants in precipitation (wet deposition) influence vegetation is by affecting soil processes, plant foliage exposed to fog and cloud, which often contain much greater concentrations of pollutant ions than rain, may be damaged directly. The idea of a critical level has been extended to define concentrations of pollutants in wet deposition above which direct damage to plants is likely. Concentrations of acidity and sulphate measured in mountain and coastal cloud are summarised. Vegetation at risk of injury is identified as montane forest growing close to the cloud base, where ion concentrations are highest. The direct effects of acidic precipitation on trees are reviewed, based on experimental exposure of plants to simulated acidic rain, fog or mist. Although most experiments have reported results in terms of pH (H(+) concentration), the accompanying anion is important, with sulphate being more damaging than nitrate. Both conifers and broadleaved tree seedlings showing subtle changes in the structural characteristics of leaf surfaces after exposure to mist or rain at or about pH 3.5, or sulphate concentration of 150 micromol litre(-1). Visible lesions on leaf surfaces occur at around pH 3 (500 micromol litre(-1) sulphate), broadleaved species tending to be more sensitive than conifers. Effects on photosynthesis and water relations, and interactions with other stresses (e.g. frost), have usually been observed only for treatments which have also caused visible injury to the leaf surface. Few experiments on the direct effects of polluted cloud have been conducted under field conditions with mature trees, which unlike seedlings in controlled conditions, may suffer a growth reduction in the absence of visible injury. Although leaching of cations (Ca(2+), Mg(2+), K(+)) is stimulated by acidic precipitation, amounts leached are small compared with root uptake, unless soils have been impoverished. This aspect of the potential effects of acidic precipitation is best considered in terms of the long-term critical-load of pollutants to the soil. Given the practical difficulties in monitoring cloud water composition, a method for defining critical levels is proposed, which uses climatological average data to identify the duration and frequency of hill cloud, and combines this information with measured or modelled concentrations of particulate sulphate in the atmosphere, to derive cloud water concentrations as a function of cloud liquid water content. For forests within 100 m of the cloud base the critical levels of particulate sulphate, corresponding to solution concentrations in the range 150-500 micromol litre(-1), are in the range 1-3.3 microg S m(-3). These concentrations are observed over much of central Europe, suggesting that many montane forests are at risk of direct effects of fossil-fuel-derived pollutants in cloud.  相似文献   

20.
Rime ice deposition and snow chemistry has been determined over a 4-year period on the summit of Cairngorm Mountain, NE Scotland. The direction of ice deposition reflected the dominant air mass movement over the summit. Sea salt concentrations in the rime ice were approximately 2.5 times greater than in snow deposited over the same period. Excess sulphate concentrations were double, and those of nitrate nearly four times higher. The direction of deposition influenced concentrations of excess sulphate and nitrogen species (nitrate and ammonium) in rime ice. The same directional effect was found in the snow chemistry indicating increased entrapment of pollutants, or a more polluted air mass, when it prevailed from a Southerly or Easterly direction. The potential surface reactions involving gaseous species of S and N may increase the ionic loading to the rime and reflect natural ionic enrichment of the rimed snowpack surface. Because of such phenomena, rime ice is proposed as a further indicator of winter air quality revealing important information on ionic interactions and total deposition flux measurement, especially at high altitudes.  相似文献   

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