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The overall project outlined in this proposal represents a series of interrelated studies designed to answer questions regarding the effects of disturbance on distribution and abundance of waterfowl and marine birds. The primary studies (i.e., aerial surveys) are directly related to the objectives identified in the Minerals Management Service (MMS) Statement-of-work regarding Monitoring Beaufort Sea Waterfowl and Marine Birds near the Prudhoe Bay Oil Field, Alaska. Additionally, we plan to include the ‘optional’ studies on eiders using off-shore barrier island habitats. Finally, we propose to conduct ground based studies designed to enhance and expand the interpretation of the aerial surveys. The specific objectives of this study are: 1. Monitor Long-tailed Duck and other species within and among industrial and control areas in a manner that will allow comparison with earlier aerial surveys using Johnson and Gazeys’ (1992) study design. a) Perform replicate aerial surveys of five previously established transects based on existing protocol (OCS-MMS 92-0060). b) Expand the area from original surveys to include near-shore areas along Beaufort Sea coastline between the original “industrial” (Jones-Return Islands) and “control” (Stockton-Maguire-Flaxman Islands) areas. c) Define the range of variation for area waterfowl and marine bird populations. Correlate this variation with environmental factors and oil and gas exploration, development, and production activities. 2. Expand aerial monitoring approximately 50 km offshore. Surveys will target Spectacled, Common and King eiders. The goal is to sample areas potentially impacted by oil spills from the Liberty, Northstar, and/or Sandpiper Units. 3. Develop a monitoring protocol for birds breeding on barrier islands, particularly Common Eiders. These data will be compared to historic data summarized by Schamel (1977) and Moitoret (1998). 4. Examine relationships between life-history parameters (e.g., fidelity, annual survival, productivity) and ranges of variation in Long-tailed Ducks and Common Eider distribution and abundance to enhance interpretation of cross-seasonal effects of disturbance. That is, the combination of aerial and ground based work has the potential to both document changes in abundance/distribution and describe those changes in terms of movements of marked individuals. Parameters will be examined in relation to disturbance using the two-tiered approach developed by Johnson and Gazey (1992). 5. Recommend cost-effective and feasible options for future monitoring programs to evaluate numbers and species of birds potentially impacted by oil spills involving ice-free and ice periods in both inshore and offshore waters.
We compared animals from a caribou (Rangifer tarandus) mortality event in the area of Point Hope and Chariot (Cape Thompson), Alaska (USA) in 1995 to hunter-killed caribou from reference sites (Barrow, Red Dog Mine, and Teshekpuk Lake, Alaska). Gross and histologic endpoints, and element levels (As, Cd, Cu, Pb, Zn, Fe) were evaluated. Starvation/malnutrition were major factors leading to death or severe weakness as very little or no fat (very low body condition scores) and serous atrophy of fat (marrow cavity and histologically) were more prevalent in caribou associated with the mortality event as compared to reference sites animals. Accumulation of hepatic hemosiderin in Kuppfer cells was noted as an indicator of cachexia. Levels of lead in feces and liver, copper the rumen contents, and arsenic in muscle were higher in caribou harvested near Red Dog Mine and might be expected in the mineral rich area, but were not at a level of concern for toxicoses. Kidney levels of cadmium were significantly increased with increasing age, and presents a potential concern for human consumers, and is an expected finding. We concluded that heavy metals played no role in the mortality event and that caribou starved. Further investigation of regional minerals differences is required to understand the sources and transport mechanisms to explain these findings and to properly address mining activity impacts. Mortality events on the north slope of Alaska are not uncommon and likely involve starvation as described here, but in most cases are not investigated, even though recent industrial activities have heightened concern.
The objectives of the project are to assess: 1) the present biodiversity of benthos in Arctic coastal ecosystems (White Sea, southern Barents Sea, Pechora Sea), and indicators for changes caused by disturbances; 2) the adaptations to the Arctic climate for some benthic key-species, the additional influence of disturbance and the sensitivity of the key-species to additional stress from disturbances; 3) the geochemical background of the regions Research activities: Annual missions by ship for sampling water, sediments and macrobenthos. Biodiversity analysis of macrobenthos in sediments in laboratories in Murmansk (MMBI) and Tromsø (Akvaplan-Niva), ecophysiological analyses in laboratories of St. Petersburg (ZISP), Yerseke (NIOO-CEMO) and Pisa (UN), analyses of pollutants in laboratories in Moscow (MSU), Nantes(UN) and Pisa (UP), geochemical analyses of water and sediment in laboratories of Moscow (MSU) and Barcelona (UB). Training of 3 PhD students
The aim of this project is to assess the deposition of HM/POP over Europe and to evaluate models. Within the framework of UN-ECE, EMEP Meteorological Synthesising Centre-East (MSC-E Moscow) organised in co-operation with RIVM, a model intercomparison for operational transport models on HM in 1995. In this intercomparison the RIVM will participate with the TREND-model. Results of the intercomparison will also be reported to the OSPAR commission. A model comparison for POPs will follow later. The RIVM/EUROS model is extended with soil and surface water modules in order to improve the description of the exchange process of POPs (deposition and re-emission). With the model, long-term averages of the deposition and accumulatation of POPs are described and scenario-studies can be carried out. In the first instance, Lindane and B(a)P will be taken as examples of POPs dominantly present respectively in the gas phase and attached to particles. When emissions are available the calculations are extended to other POPs.
The 'NAR-2000' expedition was performed during August-September 2000. The overall programme of work includes: - monitoring of pollution in air, waters and bottom sediments of freshwater lakes, soils and terrestrial vegetation - soil/botanical studies - visual and remote sensing (aerial photos and video surveys) studies of damage to soil and vegetation cover. Samples of river water and bottom sediments from 25 freshwater bodies and samples from 16 terrestrial sites in the area of the Varandey and Toravey oil fields were taken for chemical analyses.
Stationary systematic observations of pollution in atmospheric air and precipitation. During 2000, observations of contaminant levels in atmospheric air in the cities of Murmansk, Nickel, Monchegorsk, Salekhard and Norilsk were conducted. Monitoring of sulphur and nitrogen compounds in air and precipitation was continued at the above locations and also at Yaniskosky (Kola peninsula) and Pinega (Arkhangelsk region) under the EMEP programme framework. Observations of CO2 were continued at the Teriberk station. Observations of the chemical content of atmospheric precipitation were carried out at 5 stations in the Arctic network of stationary observations: in the Krasnoshelye settlement area (Kola peninsula), Naryan-Mar (Pechora river area), Dikson Island, Turuhansk (Yenisey river area), and Kusyur settlement area (Lena river). Under a joint Russian-Canadian-AMAP project, monitoring of POPs and (from 2001) mercury in air at the Amderma site is conducted.
The 'Karex - Pechora' expedition marine investigations by the research vessel 'Ivan Petrov' in the Kara and Pechora seas in August 2000, and by the research vessel 'Hydrolog' during September-October 2000. During August 2000 samples of marine water, suspended and bottom sediments at 30 oceanographic stations were analyses for contaminants. At 8 stations, hydrobiological investigations included sampling of benthic organisms, plankton and fish, for studies of bioaccumulation and transformation of contaminants.
The 'Lena-2000' expedition was performed in the area of the mouth of the Lena river and the shelf of the eastern part of the Laptev Sea during August 2000. Samples of river and marine water, suspended and bottom sediments were taken at 30 hydrological stations to study the mechanisms of contaminant transport by river water.
The expedition 'Arctic-2000' included climatic, hydrometeorological and hydrochemical studies in the eastern part of the Central Arctic Basin, during the period July-August 2000.
Brief: Assessment of the significance of aquatic food chains as a pathways of exposure of indigenous peoples to PTS, assessment of the relative importance of local and distant sources, and the role of atmospheric and riverine transport of PTS in Northern Russia. Project rationale and objectives: (1) To assess levels of Persistent Toxic Substances (PTS) in the environment in selected areas of the Russian North, their biomagnification in aquatic and terrestrial food chains, and contamination of traditional (country) foods that are important components of the diet of indigenous peoples. (2) To assess exposure of indigenous peoples in the Russian North to PTS, and the human health impacts of pollution from local and remote sources, as a basis for actions to reduce the risks associated with these exposures. (3) To inform indigenous peoples about contamination by PTS of their environment and traditional food sources, and empower them to take appropriate remedial actions to reduce health risks. (4) To enhance the position of the Russian Federation in international negotiations to reduce the use of PTS, and to empower the Russian Association of Indigenous Peoples of the North (RAIPON) to participate actively and fully in these negotiations. Project activities to achieve outcomes: (1) Inventory of local pollution sources in the vicinities of selected indigenous communities. (2) Survey of levels and fluxes of PTS in riverine and coastal marine environment important for indigenous peoples living in these environments and using them for their subsistence; and assessment of fluxes of PTS to these environments via selected rivers and the atmosphere. (3) Dietary surveys of selected indigenous communities. (4) Study of biomagnification, based on measurements of selected PTS in representative species in food chains important for the traditional diet of indigenous populations. (5) Survey and comparative assessment of pollution levels of the indigenous and general population in selected areas. (6) Dissemination of results to all relevant stakeholders.
1. Sediment study for heavy metals and selected organic contaminants. 2. Analysis of benthic organisms for heavy metals and selected organic contaminants. 3. Study of suspended sediment distribution, composition and sources. 4. Determination of partitioning of heavy metals between dissolved and particulate phases.
I. Objectives: I.1. To determine the normal range of values (natural variability due to time of year, age, gender) for basic nutritional and health parameters (blubber characteristics, essential and non-essential elements, structure of basic tissues) in the bowhead whale. a. Blubber thickness (depth and girth), chemical composition (lipids, water, calories), and tissue structure (light microscopy and special stains) will be assessed. b. Essential and non-essential elements (heavy metals) will be measured in liver and kidney. c. Tissue structure (light microscopy) characteristics obviously related to nutritional status in liver (glycogen, lipid and lipofuscin stores), pancreas (zymogen granules), and intestine (mucosal microvilli) and any evidence of inactivity/atrophy will be examined. d. Documentation of "normal" structure of basic tissues and evaluation for evidence of disease will also be conducted. I.2. Using data from Objective 1 to identify the parameters most important in assaying the health status of other mysticetes residing in the Bering Sea or Western Arctic that are harvested or stranded. I.3. Using data from Objective 1 to help determine the role of the bowhead whale as an indicator of ecosystem health and development of an optimized protocol for assessing mysticete health for the Bering Sea and Western Arctic, and other regions.
1. Research area # 2 in the 1998/99 Announcement of Opportunity by CIFAR, "Study of anthropogenic influences on the Western Arctic/Bering Sea Ecosystem", and 2. Research area #4 in the 1998/99 Announcement of Opportunity by CIFAR, "Contaminant inputs, fate and effects on the ecosystem" specifically addressing objectives a-c, except "effects." a. "Determine pathways/linkages of contaminant accumulation in species that are consumed by top predators, including humans, and determine sub-regional differences in contaminant levels..." b. "Use an ecosystems approach to determine the effects of contaminants on food web and biomagnification." c. "Encourage local community participation in planning and implementing research strategies." The objectives of Phase I, Human Ecology Research are to: 1. Document reliance by indigenous arctic marine communities in Canada, Alaska and Russia on arctic resources at risk from chemical pollutants; and, 2. Incorporate traditional knowledge systems of subsistence harvesting. The human ecology components of the project were conducted within the frameworks of indigenous environmental knowledge and community participation. Using participatory mapping techniques, semi-structured interviews and the direct participation of community members in research design, data collection and implementation, research and data collection on the human ecology of indigenous arctic marine communities was undertaken in the communities of Holman, NWT (1998), Wainwright, Alaska (1999), and is underway in Novoe Chaplino, Russia. (2000).
To monitor levels of pollutants in merlin by analysis of POPs and heavy metals in eggs and feathers. /Feathers and addled eggs of merlin were collected in 1992, 1993, 1994, 1999 and 2000 for chemical analysis of POPs and heavy metals. Comparisons with eggs from museum collections show that there has been a significant shell thinning in eggs of Norwegian merlins. From 1947 up to 1990 the eggs were on average ca. 15% thinner than normal and after 1990 the thinning has been ca. 10%. There are still high concentrations of DDE to reduce reproductive output in some cases. The PCB levels are low compared to the DDE levels and the concentrations of other chlorinated hydrocarbons are also low. Results from mercury analyses indicate possible effects on breeding performance in some adults.
The first part of the present study evaluated tissue concentrations of twelve essential and non-essential elements in four arctic marine mammal species important as subsistence resources to indigenous Alaskans. Species sampled included: bowhead whales, beluga whales, ringed seals, and polar bears. Concentrations of As, Cd, Co, Cu, Pb, Mg, Mn, Hg, Mo, Se, Ag, and Zn, were analyzed in liver, kidney, muscle, blubber, and epidermis (the latter in cetaceans only). Elements that were identified as having tissue concentrations, which in domesticated species would have been considered higher than normal and/or even toxic, were Cd, Hg, Ag, and Se. However, the concentrations of these elements were consistent with previous reports for arctic marine mammals. Remaining elements were at concentrations within normal ranges for domesticated species, although Cu was found frequently at concentrations that would be considered marginal or deficient in terrestrial domesticated animals. Across-species comparisons revealed that Cd was highest in kidney, followed by liver in all four species. Its concentrations were frequently correlated with Cu, Zn, Hg, and Se. Cadmium accumulated with age in bowhead and beluga whales, especially in liver and kidney. The relationships between Cd and Hg, and between Cd and Se were believed to be due to mutual accretion with age, although direct interactions could not be ruled out, especially with respect to Cd and Se. Associations between Cd and Cu, and Cd and Zn were potentially attributable to mutual binding with the inducible protein, metallothionein. This assumption was supported by the observation that Cd:Zn ratios in liver and kidney displayed a significant linear relationship to age and that this ratio either increased slightly (in kidney and liver of bowheads) or remained constant (in kidney and liver of belugas) with age. In general, Se was highest in liver and kidney of all four species, where it was frequently at concentrations that would have been deemed elevated or toxic for domesticated species, although within ranges previously reported for arctic marine mammals. Selenium increased with age indices, and was highly correlated with Hg, and often with Cd as well. Mercury also increased with age, and liver contained the highest tissue concentration in the cetacean and pinniped species. The pattern of Se accumulation in polar bears differed, with highest concentrations found in kidney, which suggested that this tissue may be the primary site for Hg detoxification in this species, as is the case for terrestrial mammals. Compared to the other three species, bowhead whales had very low Hg concentrations in all tissues. The highly significant linear relationship between Hg and Se noted in various tissues (particularly liver) of all four species was presumed due to binding of these two elements to each other following demethylation of MHg. This assumption was supported by the observations that while Se and Hg both accumulated with age, the fraction of total Hg that was composed of MHg decreased with age. The quantity that represented the difference between total Hg measured directly and calculated total Hg [i.e., SHg = Hg(II) + MHg], also increased with age in beluga liver. This connoted that a portion of the total Hg present was in an organic form other than MHg, and that this form accumulated with age. Alternatively, this portion, which was apparently not measured by either the Hg(II) or MHg procedures, may have been lost during extraction. Species in this study had mean hepatic Hg:Se molar ratios that were below unity. This implies that Hg concentrations may have been below some threshold level, after which subsequent accumulation proceeds in a 1:1 molar ratio fashion with Se. Alternatively, it might suggest that a 1:1 Hg:Se molar ratio is not a prerequisite for protection from Hg toxcosis among marine mammals, because none of the animals in the present study exhibited lesions typically associated with Hg toxicosis. In beluga liver, concentrations of Ag were elevated when compared to domesticated species. The only element that showed a significant linear association to Ag was Cu—a relationship that was observed in all four species. This suggested that Ag and Cu may be associated through a common ligand, possibly metallothionein. The association between Ag and Se in beluga liver was less strong than that between Hg and Se; moreover, Ag did not increase with age. These findings indicate that Ag probably does not compete with Hg for Se binding, and therefore is unlikely to substantially inhibit detoxification of Hg in beluga whales. In the second portion of this research, tissues from bowhead whales, beluga whales and ringed seals were examined at both the gross and light microscopic level. The purpose of this evaluation was three-fold: to describe the normal histologic appearance of tissues; to perform a routine histologic survey of tissues that would contribute to a general health assessment, and; to scrutinize tissues for lesions that might support a diagnosis of toxicosis caused by Cd, Hg, Ag, or Se. Tissues examined were chosen on the basis of their propensity to be targets for toxicologic injury from the specified elements (with the exception of brain) and included, but were not limited to, the tissues analyzed chemically. Special stains were used to identify particular pigments or tissue components. Overall, the bowhead whales evaluated appeared healthy and had low parasite burdens. The most common lesion, which was observed in all bowheads, was a non-inflammatory chronic renal periglomerular and interstitial fibrosis. This lesion was not typical of Cd-induced nephropathy, and it did not appear to be associated with renal Cd burdens. Nevertheless, thresholds of Cd-induced renal injury are not known for cetacean species, and more whales need to be examined histologically in conjunction with analysis of tissue Cd residues. Acute myodegeneration was observed in cardiac and/or skeletal muscle of a few bowheads, and was presumed to reflect a hunting-induced exertional myopathy. The beluga whales examined were generally in good body condition and appeared healthy grossly, but they had much higher parasite burdens than bowhead whales. In particular, prevalence in belugas of pulmonary nematodiasis was high, being especially common among whales obtained from Pt. Hope compared to those from Pt. Lay. Grossly, firm, caseous nodules were associated with lungworms, while histologically, the associated pulmonary changes ranged from mild chronic inflammation and focal granuloma formation to catarrhal granulomatous and eosinophilic verminous bronchopneumonia. Another change observed in some belugas and believed to be associated with lungworm infection, was multifocal pulmonary arterial medial hypertrophy and degeneration. Beluga whales harvested at Pt. Lay (summer) frequently showed evidence of hepatic and pancreatic atrophy, while whales taken at Pt. Hope (spring) did not. This was believed to result from anorexia during migration—a supposition corroborated by the lack of stomach contents among Pt. Lay whales. Another prominent histologic finding among belugas was hepatic telangectasia, which occurred with significantly greater frequency and severity in Pt. Hope belugas than in those from Pt. Lay. The etiology and significance of this lesion could be not be ascertained, although it was not believed to be associated with any of the elements analyzed in this study. Mild thickening of Bowman’s capsule was seen frequently in belugas. However, this lesion was not typical of Hg or Cd-induced nephropathies, and did not appear correlated with kidney concentrations of these metals. This lesion was believed to be a normal consequence of aging in belugas, although a metal etiology for it could not be excluded irrefutably. In general, ringed seals were in good body condition and appeared healthy on gross examination. Among seals evaluated histologically, the most common finding was a mild, chronic, focal or periportal hepatitis, with focal hepatocellular necrosis sometimes apparent. Although a metal etiology for this lesion could not be definitively ruled out, in the absence of other lesions that would support a diagnosis of metal toxicosis, an infectious etiology was considered more credible. Two out of sixteen seals had embryologic remnants (an epidermoid cyst and an ultimobranchial cyst)—lesions that are usually considered incidental. While no toxic (metal or otherwise) etiology could be ascertained for these lesions, the incidence of retained embryologic remnants seemed high. A number of xenobiotics are known to be endocrine-disruptors, and the potential for such an etiology among these seals should be examined further. Lipofuscin deposition was ubiquitous among all three species examined histologically. Lipofuscin was most prevalent in hepatocytes, but also commonly was observed in various other tissue and cell types, especially in cardiac and skeletal myocytes, and in uriniferous tubular epithelial cells. The third portion of this study employed autometallographic (AMG) development of light microscopic tissue sections to amplify and localize deposition of inorganic Hg in liver and kidney of beluga and bowhead whales. No staining occurred among bowhead tissues, confirming the extremely low concentration of Hg determined through chemical analyses. In beluga kidney sections, AMG granules were seen throughout the uriniferous tubular epithelium, showing that Hg deposits throughout the nephric tubule, and not solely in the proximal tubular epithelium. In liver tissue, AMG granules were deposited primarily in periportal regions among whales with lower hepatic Hg burdens. In addition to periportal deposition, AMG granules were observed in pericentral and mid-zonal regions in the belugas sampled that had higher liver Hg concentrations (generally older animals). Granules were densely concentrated in stellate macrophages, especially near portal triads. Granules also were distributed in hepatocellular cytoplasm, generally concentrated toward the bile cannalicular domain of the cell. Granules were discrete, potentially indicating that Hg was confined within lysosomes. These observations suggested that inorganic Hg deposits initially in periportal regions of young animals, with subsequent accumulation occurring pericentrally, and finally, midzonally as the whales age. Computer-assisted densitometric analysis was used for semi-quantitative evaluation of AMG staining intensities. These AMG staining intensities were well correlated with concentrations of Hg determined via chemical analysis. Areas with AMG-staining were identified and compared with location of lipofuscin in the same field, visualized with fluorescent microscopy. While AMG granules and lipofuscin deposits sometimes were co-localized, they more often were not. In addition, abundant lipofuscin deposition was seen in livers of younger belugas with little to no Hg-catalyzed AMG staining. Also, lipofuscin concentrated predominantly in pericentral regions. These observations suggested that in the healthy marine mammals of this study, marked hepatic lipofuscin deposition most often occurred independently of Hg accumulation. Consequently, hepatic lipofuscin is likely to be a poor indicator of Hg-induced damage in belugas. The abundant lipofuscin deposition in livers of marine mammals was interpreted as most likely denoting a heightened exposure to oxidative stress that is probably inherent to a marine mammalian existence. These oxidative stressors may include a diet high in polyunsaturated fatty acids (PUFAs), alternating hypoxia and abundant oxygenation, and periodic bouts of anorexia associated with migration.
Moose (Alces alces) found dead (FD) and hunter-killed (HK) in 1995 on the north slope of Alaska (Colville River drainage) were evaluated for heavy metal and mineral status. Compared to previous reports for moose and domestic cattle, and data presented here from Alaska moose outside the Colville River area, levels of copper (Cu) were determined to be low in hoof, hair, liver, kidney, rumen contents, and muscle for these north slope moose. Iron (Fe) was low in muscle as well. These findings, in conjunction with evidence of poor calf survival and adult mortality prompted investigation of a mineral deficiency in moose (serum, blood, and hair) captured in the spring of 1996 and 1997. Captured males had higher Ca, Zn and Cu levels in hair than captured females. Female moose hair samples were determined to be low (deficient) in Cu, Ca, Fe, and Se with mean levels (ppm) of 2.77, 599.7, 37.4, and 0.30, respectively. Serum Cu level was low, and to a lesser degree Zn was deficient as well. Whole blood (1997 only) was marginally deficient in Se and all animals were deficient in Cu. Based on whole blood, sera and hair, Cu levels were considered low for moose captured in spring 1996 and 1997 in the Colville River area as compared to published data and other populations evaluated in this study. Low levels of ceruloplasmin activity support this Cu deficiency theory. Evidence indicates that these moose are deficient in Cu and other minerals; however, the remote location precluded sufficient examination of animals to associate this apparent deficiency with direct effects or lesions. Renal levels of Cd increased with age at expected levels.
Population monitoring of Gyrfalcon, Golden Eagle, Willow Grouse and Passerine birds
Study changes in liver concentrations of Cd, Pb, Hg, Cu and Zn in Lagopus lagopus and Tetrao tetrix between the time periods 1990/91 and 2000/01
The aim of the project is to monitor forest health in the border areas between Norway and Russia. The impact on the forest ecosystems in the border areas is varying. In the areas close to the nickel smelter (in Nikel), the damage is serious, while the damage on the Norwegian areas are much less. Here the damage is mostly related to lack of lichen vegetation on birch stems. The moss vegetation in the bottom layer is also influenced. In some cases, when certain weather conditions fell together with high emissions of sulphur dioxide, visible damage has been developed on leaves of shrubs and trees, even on Norwegian territory. Even the emission normally does not cause visible damage on Norwegian territory; chemical influenced is traced over large Norwegian areas
The aim of the project Intensive monitoring of forest ecosystem in an air pollution gradient from Nikel and westwards, running in the period 1994-1998/99, has been to develop and perform environmental monitoring in the border areas between Norway and Russia. The project is a contribution to the joint Norwegian/Russian Environmental Co-operation. Russian scientists have established and performed analyses at four monitoring sites in Russia, while Norwegian scientists have done similar monitoring at adjacent Norwegian areas. The scientists have worked together in two workshops and in the field. The collaboration has been efficient carried out by extensive use of e-mail. An important result for of the project has been harmonised field methodology, which has been put into practice by means of common fieldwork. The impact on the forest ecosystems in the border areas is varying. In the areas close to the nickel smelter (in Nikel), the damage is serious, while the damage on the Norwegian areas are much less. Here the damage is mostly related to lack of lichen vegetation on birch stems. The moss vegetation in the bottom layer is also influenced. In some cases, when certain weather conditions fell together with high emissions of sulphur dioxide, visible damage has been developed on leaves of shrubs and trees, even on Norwegian territory. Even the emission normally does not cause visible damage on Norwegian territory; chemical influenced is traced over large Norwegian areas