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The project aims at establishing a long-term Arctic-Antarctic network of monitoring stations for atmospheric monitoring of anthropogenic pollution. Based upon the long and excellent experiences with different scientific groups performing air monitoring within the Arctic Monitoring and Assessment Programme (AMAP), an expanded network will be established including all AMAP stations and all major Antarctic “year-around” research stations. As an integrated project within the “International Polar Year 2007-08” initiative, the ATMOPOL co-operation intend to • Establish a long-term coordinated international Arctic-Antarctic contaminant programme. • Develop and implement a joint sampling and monitoring strategy as an official guideline for all participating stations. • Support bi-polar international atmospheric research with high-quality data on atmospheric long-range transport of contaminants (sources, pathways and fate). • Support future risk assessment of contaminants for Polar Regions based on effects of relevant contamination levels and polar organisms Based upon the well-established experiences of circum-Arctic atmospheric contaminant monitoring in the Arctic under the AMAP umbrella, a bi-polar atmospheric contaminant network will be established and maintained. In conjunction with the polar network of atmospheric monitoring stations for air pollution, surface-based and satellite instrumentation will be utilised to provide the characterization of the Arctic atmospheric-water-ice cycle. Together with numerical weather prediction and chemical transport model calculations, simultaneous measurements of pollutants at various locations in the Arctic and Antarctic will enhance our understanding of chemical transport and distribution as well as their long-term atmospheric trends. In addition to investigating the importance of atmospheric transport of pollutants an understanding of the transference and impact of these pollutants on both terrestrial and marine environments will be sought. A secretariat and a “scientific project board” will be established. During this initial phase of the project (2006), a guideline on priority target compounds, sampling strategies, equipment and instrumentation, analytical requirements, as well as quality assurance protocols (including laboratory intercalibration exercises) will be developed and implemented. The ATMOPOL initiative aims to address highly relevant environmental change processes and, thus, will strive to answering the following scientific questions: • How does climate change influence the atmospheric long-range transport of pollutants? • Are environmental scientists able to fill the gaps in international pollution inventories and identification of possible sources for atmospheric pollution in Polar Regions? • What are the differences in transport pathways and distribution patterns of various atmospheric pollutants between Arctic and Antarctic environments? Why are there such differences? What is the final fate of atmospherically transported pollutants and how does this impact on the environment and indigenous people?In order to understand the underlying atmospheric chemistry of pollution, e.g. atmospheric mercury deposition events, routine surface measurements of UV radiation as well as campaign related measurements of UV radiation profiles will also be included.The project will establish a cooperative network on atmospheric contaminant monitoring in Polar Regions far beyond the IPY 2007/08 period and is, thus, planned as an “open-end” programme. All produced data will be available for all participating institutions for scientific purposes as basis for joint publications and reports from the ATMOPOL database to be developed.
The aim of this research program is to examine the response of animal populations to environmental variability at different spatial scales. We attempt to determine how individuals respond to the spatial heterogeneity of their environment, and what are the consequences of this response for the dynamics of subdivided populations. Specifically, we consider an ecological system involving biotic interactions at three levels: seabirds, their tick _Ixodes uriae_, and the microparasite _Borrelia burgdorferi_ sensu lato (Lyme disease agent). Colonies of seabirds represent discrete entities, within and among which parasites can circulate. Our previous work on this system in the norwegian arctic has enable us to show that (1) host dispersal can be affected by local conditions, (2) seabird tick populations are specialised among different host species, namely between sympatric kittiwakes _Rissa tridactyla_ and puffins _Fratercula arctica_, (3) in the kittiwake, females transmit antibodies against _Borrelia burgdorferi_ when their chicks have a high probability to be exposed to the tick vector. We propose to combine different approaches, incorporating field surveys and experiments and population genetic studies (of hosts and parasites), in order to better understand the role of local interactions and dispersal in the dynamics of such a system. The research program implies collaborations with researchers from other french groups, as well as with Canadian (Queen’s University) and Norwegian colleagues (from NINA and the University of Tromsø).
The project will provide a long-term, pseudo-global validation support to the ENVISAT-1 atmospheric measurements, based on mutually consistent high-quality solar and lunar observations from FTIR spectrometers operated at primary and a number of complementary NDSC stations. The validation is limited to a number of target species, most of which are primary NRT or OL level-2 products of the mission, with focus on NOy components: O3, NO2, NO, N2O, HNO3, HNO4, H2CO, CO and CH4. Synergistic use will be made of column and profile data from MIPAS, GOMOS and SCIAMACHY. The ground network will deliver mean vertical column abundances for all target species with NDSC-type quality, and height profile information for some target gases as secondary products to the PI's home institute, where the correlative analyses with the ENVISAT-1 products will be done. Asynoptic mapping tools will support the validation efforts.
Large numbers of birds breed each summer on the tundra of the northern hemisphere. Two prominent groups in the Arctic bird fauna are waders and waterfowl (ducks, geese and swans). Breeding, which is an energetically costly activity (Drent & Daan 1980), is especially costly in the high Arctic. This is mainly due to low temperatures and high wind speeds in an open landscape (Piersma & Morrison 1994, Wiersma & Piersma 1994). In addition, the summer period is very short. This leaves little time for necessary pre-breeding, breeding and post-breeding activities. Thus, costs are high and available time is short. In order to reach their breeding grounds, arctic birds have to migrate over vast distances between their Arctic breeding sites and temperate or tropical wintering grounds. Migration is also an energetically costly event. This generally high rate of living puts high demands on the birds and we may expect the birds to have evolved a wide range of physiological and behavioural adaptations. Given the inaccessibility of most tundra areas and the necessity of relatively advanced techniques, ecological energetic studies of wader and waterfowl are relatively scarce (with the notable exception of tundra breeding Nearctic geese). With this project we aim at measuring and describing some important energy turnover processes of waders and waterfowl during the short and hectic Arctic summer and to evaluate them in an evolutionary context. We will pay particular attention to the importance of energy and nutrient stores with which the birds arrive at the breeding grounds for egg production, energy turnover of breeding birds in relation to species and microclimate, and the fat deposition and basal metabolism of birds preparing for autumn migration. The project is partly a continuation of work carried out during the Swedish-Russian Tundra Ecology Expedition 1994 (TE-94). Research activities: Capital vs. income breeders Since the favourable season is short for Arctic breeding birds, they are hard pressed to start egg laying immediately after arrival at the breeding grounds. However, upon arrival food availability is often low. It is thought that female birds planning to start a family on the tundra are forced to produce a clutch using, at least to some degree, body reserves accumulated prior to or during their migratory journey. Birds using such a strategy are called capital breeders, in contrast to income breeders' that only use resources obtained during the reproductive period (Drent & Daan 1980). We seek to investigate how commonly the capital breeder strategy is on the Nearctic tundra and how its use varies with: - Species: large species are expected to be more dependent on this - Strategy as their breeding seasons are longer and they are thus more time stressed. - Site: birds at sites where circumstances allow an early start of the breeding season may not be equally dependent on capital breeding than birds using late sites. - Timing: early arriving birds are more pressed to use the capital breeding strategy than late arriving birds, the latter being able to produce eggs from the food available upon arrival. The different potential food sources to birds often have distinct isotopic ratios of C12/C13 and N14/N15 depending on environment and metabolic characteristics. Isotopic ratios of C and N can therefore serve as a kind of fingerprint for these food stuffs. These specific ratios will ultimately also be reflected in the isotopic composition of the consumers tissues; especially with regard to C12/C13 ratios (Hobson & Clark 1992). Distinct differences may therefore also be expected in tissue isotope ratios of newly hatched young from capital and non-capital breeders. Such differences may also appear within nests in case the female has used a mixed strategy. Although in developing tissues these differences may rapidly fade away, isotope differences between young may be fixed in down feathers already present at hatching. Comparing the isotope ratios in down samples within broods with isotope ratios in potential food sources at the breeding ground thus provides a clue to the extend the mother made use of the capital breeding strategy. We will collect down, feathers and blood from all birds trapped. We will concentrate on waders, yet, also waterfowl are of high interest (although the chances to trap birds are smaller). Of highest priority will be down from chicks and blood from parent birds. In likely foraging areas of parents and chicks that we have sampled, we will collect insects and plants and other possible food sources. At the NIOO the samples will be analysed for C12/C13 and N14/N15 ratios using mass spectrometry. The fact that we will visit many different habitats with different climate, foraging conditions and phenology is a major prerequisite for successfully conducting this part of the project. Energy turnover of brooding birds The few available measurements of daily energy expenditure (DEE) of incubating waders in tundra regions, using the doubly labelled water (DLW) method, have shown that breeding in the High Arctic is indeed costly (Piersma & Morrison 1994, Piersma et al. unpublished data from Siberia). The high cost stems from the combined effects of low temperatures and high wind speeds in an open landscape, but may also be affected by the birds own intense foraging activities. However, the measurements that have become available up till now do not cover the whole "climate space" that arctic breeding waders encounter, due to the bias in study sites and the particularities of weather conditions during the few studies that have been carried out. We would like to extend the series of measurements using DLW in incubating waders of more species than hitherto available and under more environmental conditions. Field measurements of DEE involve initial capture of a bird on the nest, loading it with DLW and recapturing the bird after a certain period of time, usually 24-48 hours. There is room for improvement over the earlier studies in monitoring the loaded birds activity budget (using transponders, small radiotags and/or nest/egg temperature recorders) and in assaying the birds physiological status. Apart from mass and size variable, birds could probably be assayed for the thickness of the breast muscle (a heat generating part of the body) and the size of the stomach (as an indicator of the digestive apparatus) using ultrasound. These techniques are under development at NIOZ and the University of Groningen at the moment. Equally, body composition in terms of fat and lean components could be estimated from dilution factors after quantitative DLW injections. It is crucial to simultaneously measure the meteorological variables air temperature, wind speed and global solar radiation, and hence a weather station has to be brought to the study sites to this effect. Fat deposition and basal metabolism of birds preparing for autumn migration Waders need high-performing bodies to cope with their energetically high rate of living. This is reflected in their basal metabolic rate (BMR). The BMR of an animal is the energy it spends at rest (i.e., at night for day-active animals), in thermoneutral conditions, without processing food, and when it is not involved in productive activities like reproduction, moult or growth. The BMR of a bird may be compared with the fuel consumption of a car engine that is running idle. A Formula-One car, that operates at an incredibly high rate also has a high cost of running idle. A standard car with a less impressive engine takes less energy to keep running. As the cost of running idle reflects the potential power of an engine, the BMR reflects the potential rate of work of an animal body. Waders have comparatively high BMR compared to other non-passerine birds (Kersten & Piersma 1987). Moreover, studies of captive Knots have shown that they vary their BMR over the year (Piersma et al. 1995). In addition, waders trapped during the first part of their autumn migration in Arctic Eurasia were found to have higher BMR than their conspecifics at tropical wintering grounds in Africa (Kersten et al. in press, Lindström in press a). This all suggests that waders can adjust the size of their engine which makes sense, since the best solution would be to have a strong engine when circumstances so demand, and a smaller engine during more relaxed parts of the year (for example at wintering grounds in Africa; Klaassen et al. 1990). Although we are actually most interested in the long-term maximum rate of energy expenditure as a measure of adaptations to a high rate of living, this is very difficult to measure, and especially so in a comparable way. Instead, the BMR, which is supposed to reflect the maximum energy turnover potential, is fairly easy to measure, and figures from different investigations can be compared. During TE-94, 24 juvenile waders of five different species were measured for their BMR in a respirometer (Lindström in press a). We want to continue this work by including birds of new species, and of the same species but from another breeding area. Juvenile birds will be caught during the first parts of the autumn migration (mainly August) in portable and walk-in traps. They are then brought to the ship where they will be measured in the respirometer. The BMR values will be compared to those obtained during TE-94 and with data from the migration and the wintering grounds in America and Europe to look for inter- and intra-specific patterns. Whereas it is fairly well known that many (most ?) wader species put on huge energy reserves prior to migration to the Arctic, almost nothing is known about the size of reserves carried by waders prior to departure from the Arctic. This is necessary to know in order to understand the migration strategies adopted (Alerstam & Lindström 1990) and when analysing migration routes. During TE-94 almost 300 juvenile waders were trapped during August, most of them being Little Stints Calidris minuta. It was revealed that also when migrating from the Arctic, substantial energy reserves were put on (Lindström in press b). We now want to collect corresponding data from the Nearctic. Whereas much is known about the size of energy reserves of migration waders further south in America (for example, McNeil & Cadieux 1972, Thompson 1974, Johnson et al. 1989, Driedzic et al. 1993), we know of no such data from the Nearctic region.
Study of the Holocene development in the coastal area of Nova Scotia and New Brunswick (Canada), in relation to sea-level movements, isostatic movements and climate development, particularly for the last 4500 years. Use of stratigraphical and sedimentological methods and of 14C-dating.
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).
The objectives of this study were to develop baseline data on persistent organic pollutants (POPs) and metals, in freshwater and anadromous fish, shellfish, and marine mammals, important to Inuit communities of Northern Labrador and Nunavik in order to provide the same level of information that is available for other Canadian arctic regions. 1999-00 was the final year of the project. Successful collection of mussels (Mytilus edulis), arctic char (sea run), scallops and walrus samples were made in 1999. During 1998 major collections of ringed seal, sea run arctic char and blube mussels (Mytilus edulis) were made. Chemical analyses of POPs and metals in ringed seals and char collected in 1998-99 were completed in 1999-2000. Low concentrations of mercury, selenium and lead were found in samples of scallops from Labrador while cadmium and arsenic levels were much higher than the other elements, especially in gut samples. Arsenic was the most prominent of the five metals determined in mussels from Nunavik. Mercury levels were low (0.02-0.03 ug/g wet wt) in char from Labrador collected in 1999 similar to our previous observations in Labrador and Nunavik. Much higher levels of mercury and selenium were found in landlocked char (at Kangiqsujuaq) and than in all sea run char from widely separated sites Nunavik and Labrador. Mercury and selenium levels in seal liver did not differ among the 5 locations after adjustment for age of the animals. Percent organic mercury levels increased with age in seal muscle from about 80% in animals from 0-2 yrs to about 100% in adult animals. Mercury levels in walrus meat (muscle) were relatively low compared with liver and kidney. Levels of tributyl tin in char muscle ranged from <0.01 to 0.85 ng/g wet wt and highest levels were found in samples from Kangirsuk (Ungava Bay region). PCBs and other organochlorines were present at very low levels in mussels and arctic char from locations in Nunavik and Labrador. In general, levels of PCBs and SDDT in ringed seal blubber in this study were similar to levels found in ringed seal blubber at other eastern Arctic locations.
Risk determination for traditional food should consider the potential risks from exposure to contaminants and the sociocultural, nutritional, economic and spiritual benefits associated with traditional food. Factors which influence Inuit food choices should be further analyzed to add precision to the evaluation of risks and benefits of traditional food consumption. The data of the Nutrition Santé Québec Survey are a potential source for this type of analysis since data are available and are representative of the entire region of Nunavik. The proposed work consists of more detailed analysis of the existing data on food intake among the Inuit of Nunavik collected in 1992 during the Santé Québec Health Survey and to extend our analyses to contaminant intakes. Intakes (mean and median) of traditional and market foods, nutrients and contaminants will be calculated according to the makeup/structure of households, the level of education, the level of household income and coastal place of residence. Intakes will also calculated according to the social assistance status of Inuit. Among Inuit depending on social assistance, comparisons of food, nutrient and contaminant intakes according to the time of the month in which the survey took place will be examined. Statistical comparisons of food intakes will also be done between Inuit who stated having lacked food in the month prior to the survey and those who did not. Nutrient intakes will be compared with daily recommended nutrient intakes (RNI) based on nutritional recommendations issued by Health Canada. More detailed and reliable information regarding sociodemographic factors affecting food intake, nutritional status and contaminant exposure among Inuit will help to orient public health authorities in the promotion of health through traditional food consumption.
Among all contaminants present in different aquatic ecosystems in Canada, methylmercury (MeHg) is a major source of concern for public health. Currently, it is difficult to reliably determine the threshold of MeHg concentration at which functional changes occur. On the other hand, it is well known that chronic MeHg exposure is very harmful for the nervous system. Oxidative reactions appear to be of central importance to mercury toxicity. Therefore, it is important and urgent to determine with precision the minimal dose at which oxidative stress and neurotoxic effects can be identified since some studies suggest that MeHg toxicity can be detected at level far below the minimal exposure level proposed by the World Health Organization. The main goal of this project is to investigate the effects of mercury on sensorimotor functions in the population of Salluit. We will examine the relationship between the level of MeHg and sensorimotor performance. Afterwards, specific recommendations based on quantitative evidence will be made to the concerned populations so as to diminish long-term risk on health.
This study investigates possible detrimental effects on the immune system of Inuit infants which may be induced by prenatal and postnatal (breast feeding) exposure to persistent environmental contaminants such as organochlorine compounds. These substances accumulate in the body of Inuit women in part due to their consumption of sea mammal fat and can be transferred to the foetus during pregnacy and to the infant during breast feeding. Immune system function will be evaluated using several parameters: 1) the level of antibody produced by the infant following Haemophilus influenza immunization; 2) the level of proteins which protect the infant against bacterial infections (complement system) before its immune system is fully developed; and 3) the level of chemical messengers (cytokines) which enable the various cells of the immune system to communicate with each other, thereby maintaining its proper function and assuring the protection of the infant against bacteria, parasitic and viral infections.
The main purpose of this research is to examine the consequences of in utero exposure to PCBs on Inuit infants, from birth to 11 months of age. Of particular interest is the impact of PCBs and mercury exposure on newborn’s thyroid hormones, physical growth, physical and central nervous system maturity, on infant’s overall health, mental, psychomotor and neurobehavioral development, and on functional and neural impairment in the domains of visual and spatial information processing. The proposed project is designed to replicate and extend previous findings by studying a more highly exposed cohort of infant, and using new infant assessment paradigms that have been linked to specific brain regions and neural pathways and, therefore, have a potential to provide information regarding possible mechanisms of action. The second objective of this research is to document the exposure to heavy metals, organochlorines and polyunsaturated fatty acids of newborns from selected communities in Nunavik. This ongoing effect study provides the opportunity to perform long time trend analysis of human exposure (data available for same communities since 1993).
The purpose of this research is to examine the long term consequences of prenatal exposure to PCBs and MeHg. This project is designed to study domains of effects overlooked in most of the previous studies. Of particular interest is the impact of exposure on neurophysiological and neurological endpoints that could be related to learning difficulties and disabilities. This study will support the health risk assessment process by providing dose-effect analysis for the neurophysiological and neurological domains of effects of preschool age children from Nunavik (Canada). The total sample will comprise 100 Nunavik Inuit children aged 5-6years. The following exclusion criteria will be applied: Apgar below 5 at 5 minutes of life, evidence of birth trauma, less than 37 weeks of gestation and less than 2500 grams at birth, congenital or chromosomal anomalies, epilepsy, significant disease history, major neurological impairment, fetal alcohol syndrome, presence of facial dysmorphologies associated with fetal alcohol effects.
The objective of the study is to establish baseline levels of specific heavy metal and organochlorine contaminants in the blood of women and their newborns, from communities in the Inuvik Region. The study examines traditional food consumption as a possible contaminant exposure pathway, while measuring organochlorines and metals in maternal and cord blood, as well as mercury levels in maternal hair. Collection of data from this region will complete the Northwest Territories/Nunavut database on maternal and cord blood. There were 104 women participating in this study from Inuvialuit, Gwich'in and non-native backgrounds. The results are similar to existing data from other regions in the Canadian north and confirm the importance of traditional foods among women of reproductive age. Exposure levels to contaminants were generally within guideline levels with only a few exceptions. Communication of results to the communities will continue until June 2000. Objectives: 1.To obtain regional values for the concentrations of organochlorine and metal contaminants in maternal and umbilical cord blood samples, and the concentration of mercury in hair samples from pregnant women in the Inuvik region. 2.To assess exposure to these contaminants through the frequency of traditional/country food intake and certain other lifestyle factors. 3.To describe any relationship between contaminant levels in blood and hair samples and frequency of consumption of traditional/country foods and selected lifestyle factors.
To examine concentrations and biological effects of selected trace elements in king and common eiders from various locations in the Canadian arctic.
The objectives of the project are: A) to determine temporal trends in atmospheric mercury concentrations and deposition processes of mercury in the Arctic, and to assist in the development of long-term strategies for this priority pollutant by: i) measuring ambient air Total Gaseous Mercury (TGM) concentrations in the Canadian Arctic (Alert) and investigating the linkage to elevated levels of mercury known to be present in the Arctic food chain; ii) investigating and establishing the causes of temporal variability (seasonal, annual) in mercury concentrations so that realistic representations (models) of atmospheric pathways and processes can be formulated, tested and validated; iii) studying the chemical and physical aspects of atmospheric mercury vapour transformation (oxidation) after polar sunrise and the resultant enhanced mercury deposition to the sea, snow and ice surfaces each year during springtime; and iv) obtaining a long-term time series of atmospheric mercury (TGM) concentrations at Alert for the purpose of establishing whether mercury in the troposphere of the northern hemisphere is (still) increasing and if so, at what rate; B) to establish a sound scientific basis for addressing existing gaps of knowledge of the behaviour of mercury in the Arctic environment that will enable international regulatory actions to reflect the appropriate environmental protection strategies and pollution controls for the Arctic by: i) studying the relative roles of anthropogenic and natural sources of mercury so as to clarify understanding of the atmospheric pathways leading to the availability of mercury to Arctic biota; ii) studying tropospheric TGM depletion mechanisms/processes leading to enhanced input of mercury to the Arctic biosphere in spring; iii) undertaking essential speciated measurements of particulate-phase and/or reactive gaseous-phase mercury as well as mercury in precipitation (snow/rain) to quantify wet and dry deposition fluxes into the Arctic environment; and vi) providing the scientific basis for the information and advice used in the preparation and development of Canadian international strategies and negotiating positions for appropriate international control objectives.
The objectives of this project are: A) to determine the pathway for the transfer of mercury in snowmelt to sea water during the melt period at Alert; B) to determine the extent of open water and wet ice in the summer Arctic as it affects the surface exchange of Hg using satellite radar imagery; and C) to determine the atmospheric dynamics associated with the photochemistry of mercury episodically during the polar sunrise period.
The objectives of this project are A) to determine coplanar polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), brominated diphenyl ethers (BDPEs), chlorophenolic compounds and chloroparaffins in air from arctic monitoring stations; and B) to search for other "new" chemicals in the arctic environment, not currently monitored by Canada's Northern Contaminants Program (NCP) but of potential concern based on known persistence, extent of usage and toxicology.
1. To determine the depth profiles of mercury (Hg) and lead (Pb) as well as manganese (Mn) and iron (Fe) in fifteen dated Arctic sediment cores over a three year period. Mercury is the main focus. 2. To quantify geographical trends in fluxes of the mercury and its enrichment factors in Nunavut, NWT, Nunavik, and Labrador. To link mercury findings with those of paleolimnological indicators, POPs, as well as indicators of biogeochemical processes of manganese and iron, all of which are obtained from the same cores, or cores from the same sites whenever possible. 3. To complement existing data on mercury in Arctic sediment cores with data generated over a much wider latitudinal and longitudinal range than previous work in order to provide a better understanding of Hg in Canada North. 4. Secondary to Hg, to provide loading data for Pb which may help elucidate the understanding of Hg pathways and sources.