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Sample records for subarctic environment annual

  1. Europeanization of sub-Arctic environments: soils based evidence from Norse Greenland

    Science.gov (United States)

    Simpson, Ian; Collinge, Kirsty; Adderley, Paul; Wilson, Clare

    2014-05-01

    Europeanization of sub-Arctic environments by Norse communities in Greenland from the early 11th to mid 15th centuries AD varied spatially and temporally, with pastoral agriculture and associated homefield management at the heart of this transformation. This process is poorly understood and so from inner, middle and outer fjord areas of the Norse Eastern settlement in Greenland we contribute a chronologically constrained homefield soils and sediments-based historical ecodynamic analysis. Our findings demonstrate a range of homefield management activities in contrasting environmental and social settings including a) 'recipe effects' - the partitioning of turf, domestic animal manure and domestic waste resources used to manage soil fertility and the effects of eroded material deposition in the homefield; b) field irrigation management to overcome seasonal water limitations; and c) 'non-management' where homefield productivities relied on natural soil fertilities. These management practices created an anthrosols soil environment overlying and distinct from the podsolic environment at settlement. In doing so Norse settlers increased soil nutrient status relative to pre-settlement levels in some homefields, whilst nutrient levels in other areas of the homefield were allowed to decline, resulting in a situation of 'partial sustainability'. We demonstrate that in historical contexts, local 'partial sustainability' can lead to resilience amongst agricultural communities in the face of climatic deterioration, but that ultimately this may only be as effective as the broader social framework in which it is found.

  2. Potential of C and X Band SAR for Shrub Growth Monitoring in Sub-Arctic Environments

    Directory of Open Access Journals (Sweden)

    Yannick Duguay

    2015-07-01

    Full Text Available The Arctic and sub-Arctic environments have seen a rapid growth of shrub vegetation at the expense of the Arctic tundra in recent decades. In order to develop better tools to assess and understand this phenomenon, the sensitivity of multi-polarized SAR backscattering at C and X band to shrub density and height is studied under various conditions. RADARSAT-2 and TerraSAR-X images were acquired from November 2011 to March 2012 over the Umiujaq community in northern Quebec (56.55°N, 76.55°W and compared to in situ measurements of shrub vegetation density and height collected during the summer of 2009. The results show that σ0 is sensitive to changes in shrub coverage up to 20% and is sensitive to changes in shrub height up to around 1 m. The cross-polarized backscattering (σ0 HV displays the best sensitivity to both shrub height and density, and RADARSAT-2 is more sensitive to shrub height, as TerraSAR-X tends to saturate more rapidly with increasing volume scattering from the shrub branches. These results demonstrate that SAR data could provide essential information, not only on Remote Sens. 2015, 7 9411 the spatial expansion of shrub vegetation, but also on its vertical growth, especially at early stages of colonization.

  3. Uncertainty in the impacts of projected climate change on the hydrology of a subarctic environment: Liard River Basin

    Directory of Open Access Journals (Sweden)

    R. Thorne

    2011-05-01

    Full Text Available Like many high latitude areas, the mountainous region of subarctic Canada has experienced recent warming and is an area of large inter-annual temperature variations, most notably during the winter. Quantifying how climate tendencies affect streamflow, especially in the spring melt season, is critical not only to regional water resource management, but to understanding the influence of freshwater on the Arctic sea-ice cover and global climate system. The impact of projected atmospheric warming on the discharge of the Liard River is unclear. Here, uncertainty in climate projections associated with GCM structure (2 °C prescribed warming and magnitude of increases in global mean air temperature (1 to 6 °C on the river discharge are assessed using a well-tested, semi-distributed hydrological model. Analyses have shown that the hydrological impacts are highly dependant on the GCM scenario. Uncertainties between the GCM scenarios are driven by the inconsistencies in projected spatial variability and magnitude of precipitation, rather than warming temperatures. Despite these uncertainties, the entire scenario simulations project that the subarctic nival regime will be preserved in the future, but the magnitude of change in river discharge is highly uncertain. Generally, spring freshet will arrive earlier, autumn to spring discharge will increase whereas summer flow will decrease, leading to an overall increase in annual discharge.

  4. Reconciling biodiversity conservation and agricultural expansion in the subarctic environment of Iceland

    Directory of Open Access Journals (Sweden)

    Lilja Jóhannesdóttir

    2017-03-01

    Full Text Available Intensified agricultural practices have driven biodiversity loss throughout the world, and although many actions aimed at halting and reversing these declines have been developed, their effectiveness depends greatly on the willingness of stakeholders to take part in conservation management. Knowledge of the willingness and capacity of landowners to engage with conservation can therefore be key to designing successful management strategies in agricultural land. In Iceland, agriculture is currently at a relatively low intensity but is very likely to expand in the near future. At the same time, Iceland supports internationally important breeding populations of many ground-nesting birds that could be seriously impacted by further expansion of agricultural activities. To understand the views of Icelandic farmers toward bird conservation, given the current potential for agricultural expansion, 62 farms across Iceland were visited and farmers were interviewed, using a structured questionnaire survey in which respondents indicated of a series of future actions. Most farmers intend to increase the area of cultivated land in the near future, and despite considering having rich birdlife on their land to be very important, most also report they are unlikely to specifically consider bird conservation in their management, even if financial compensation were available. However, as no agri-environment schemes are currently in place in Iceland, this concept is highly unfamiliar to Icelandic farmers. Nearly all respondents were unwilling, and thought it would be impossible, to delay harvest, but many were willing to consider sparing important patches of land and/or maintaining existing pools within fields (a key habitat feature for breeding waders. Farmers' views on the importance of having rich birdlife on their land and their willingness to participate in bird conservation provide a potential platform for the codesign of conservation management with landowners

  5. A preliminary assessment of glacier melt-model parameter sensitivity and transferability in a dry subarctic environment

    Directory of Open Access Journals (Sweden)

    A. H. MacDougall

    2011-11-01

    Full Text Available Efforts to project the long-term melt of mountain glaciers and ice-caps require that melt models developed and calibrated for well studied locations be transferable over large regions. Here we assess the sensitivity and transferability of parameters within several commonly used melt models for two proximal sites in a dry subarctic environment of northwestern Canada. The models range in complexity from a classical degree-day model to a simplified energy-balance model. Parameter sensitivity is first evaluated by tuning the melt models to the output of an energy balance model forced with idealized inputs. This exercise allows us to explore parameter sensitivity both to glacier geometric attributes and surface characteristics, as well as to meteorological conditions. We then investigate the effect of model tuning with different statistics, including a weighted coefficient of determination (wR2, the Nash-Sutcliffe efficiency criterion (E, mean absolute error (MAE and root mean squared error (RMSE. Finally we examine model parameter transferability between two neighbouring glaciers over two melt seasons using mass balance data collected in the St. Elias Mountains of the southwest Yukon. The temperature-index model parameters appear generally sensitive to glacier aspect, mean surface elevation, albedo, wind speed, mean annual temperature and temperature lapse rate. The simplified energy balance model parameters are sensitive primarily to snow albedo. Model tuning with E, MAE and RMSE produces similar, or in some cases identical, parameter values. In twelve tests of spatial and/or temporal parameter transferability, the results with the lowest RMSE values with respect to ablation stake measurements were achieved twice with a classical temperature-index (degree-day model, three times with a temperature-index model in which the melt parameter is a function of potential radiation, and seven times with a simplified energy

  6. A comparison of annual and seasonal carbon dioxide effluxes between subarctic Sweden and high-arctic Svalbard

    DEFF Research Database (Denmark)

    Björkman, Mats P.; Morgner, Elke; Björk, Robert G.

    2010-01-01

    estimated in High-Arctic Adventdalen, Svalbard, and sub-Arctic Latnjajaure, Sweden, using a new trace gas-based method to track real-time diffusion rates through the snow. Summer measurements from snow-free soils were made using a chamber-based method. Measurements were obtained from different snow regimes...

  7. Comparison of Vegetation Water Use Using the Horton Index in a Sub-arctic, Alaskan Boreal Forest Environment Using Hydrograph Analysis

    Science.gov (United States)

    Bolton, W. R.; Cable, J.

    2012-12-01

    The sub-arctic environment is in the zone of discontinuous permafrost. The extreme energy influx from winter to summer has a strong influence on water storage and release processes at the watershed scale. For example, the seven months of snow accumulation are followed by a short 2-week period of snow ablation in which approximately 1/3 of the annual precipitation is released into the system. In permafrost soils, the soils begin to thaw immediately at the conclusion of snow melt, increasing the storage capacity of the soils. The storage capacity of the soils reaches a maximum in late summer then rapidly decreases during the freeze-back period in October. In permafrost-free soils dominated by deciduous vegetation, the trees appear to have a major role in taking up and transpiring liquid precipitation to back to the atmosphere. Conversely, in permafrost soils dominated by coniferous vegetation, the trees appear to have a more minor role in the cycling of liquid water during precipitation events. The overarching goal of our research is to quantify the relative roles of vegetation water use and soil storage dynamics associated with permafrost presence/absence in determining the magnitude and timing of water pathways in the sub-Arctic boreal forest. As part of this goal, we quantified the Horton Index - a metric used to describe vegetation water use relative to available soil water - in two small sub-basins of the Caribou-Poker Creeks Research Watershed, located near Fairbanks, Alaska. The C2 (5.2 km2) and C3 (5.7km2) sub-basins are underlain by approximately 2 and 53% permafrost, and are dominated by deciduous (Betula neoalaskana and Populus tremuloides) and coniferous vegetation (Picea mariana), respectively. Catchment scale calculations of the Horton Index are made using stream flow analysis and during snow-free precipitation events over an 11-year period. In each sub-basin, the Horton Index varies with time with the greatest variation occurring in the spring and fall

  8. Low below-ground organic carbon storage in a subarctic Alpine permafrost environment

    Science.gov (United States)

    Fuchs, M.; Kuhry, P.; Hugelius, G.

    2015-03-01

    This study investigates the soil organic carbon (SOC) storage in Tarfala Valley, northern Sweden. Field inventories, upscaled based on land cover, show that this alpine permafrost environment does not store large amounts of SOC, with an estimate mean of 0.9 ± 0.2 kg C m-2 for the upper meter of soil. This is 1 to 2 orders of magnitude lower than what has been reported for lowland permafrost terrain. The SOC storage varies for different land cover classes and ranges from 0.05 kg C m-2 for stone-dominated to 8.4 kg C m-2 for grass-dominated areas. No signs of organic matter burial through cryoturbation or slope processes were found, and radiocarbon-dated SOC is generally of recent origin (logistic regression model, showed that at an altitude where permafrost is probable the SOC storage is very low. In the high-altitude permafrost zones (above 1500 m), soils store only ca. 0.1 kg C m-2. Under future climate warming, an upward shift of vegetation zones may lead to a net ecosystem C uptake from increased biomass and soil development. As a consequence, alpine permafrost environments could act as a net carbon sink in the future, as there is no loss of older or deeper SOC from thawing permafrost.

  9. Temperature and substrate controls on intra-annual variation in ecosystem respiration in two subarctic vegetation types

    DEFF Research Database (Denmark)

    Grogan, Paul; Jonasson, Sven Evert

    2005-01-01

    contributions of bulk soil organic matter and plant-associated carbon pools to ecosystem respiration is critical to predicting the response of arctic ecosystem net carbon balance to climate change. In this study, we determined the variation in ecosystem respiration rates from birch forest understory and heath...... tundra vegetation types in northern Sweden through a full annual cycle. We used a plant biomass removal treatment to differentiate bulk soil organic matter respiration from total ecosystem respiration in each vegetation type. Plant-associated and bulk soil organic matter carbon pools each contributed...... significantly to ecosystem respiration during most phases of winter and summer in the two vegetation types. Ecosystem respiration rates through the year did not differ significantly between vegetation types despite substantial differences in biomass pools, soil depth and temperature regime. Most (76...

  10. Pristine Arctic: Background mapping of PAHs, PAH metabolites and inorganic trace elements in the North-Atlantic Arctic and sub-Arctic coastal environment

    Energy Technology Data Exchange (ETDEWEB)

    Jörundsdóttir, Hrönn Ólína, E-mail: hronn.o.jorundsdottir@matis.is [Matis Ltd., Icelandic Food and Biotech R and D, Vinlandsleid 12, 113 Reykjavik (Iceland); Jensen, Sophie [Matis Ltd., Icelandic Food and Biotech R and D, Vinlandsleid 12, 113 Reykjavik (Iceland); Hylland, Ketil; Holth, Tor Fredrik [Department of Biosciences, University of Oslo, P.O. Box 1066 Blindern, N-0316 Oslo (Norway); Gunnlaugsdóttir, Helga [Matis Ltd., Icelandic Food and Biotech R and D, Vinlandsleid 12, 113 Reykjavik (Iceland); Svavarsson, Jörundur [University of Iceland, Department of Life and Environmental Sciences, Askja - Natural Science Building, Sturlugata 7, 101 Reykjavík (Iceland); Ólafsdóttir, Ásdís [The University of Iceland´s Research Centre in Sudurnes, Gardvegi 1, 245 Sandgerdi (Iceland); El-Taliawy, Haitham [Matis Ltd., Icelandic Food and Biotech R and D, Vinlandsleid 12, 113 Reykjavik (Iceland); Rigét, Frank; Strand, Jakob [Department of Bioscience, Arctic Research Centre, Aarhus University, Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde (Denmark); Nyberg, Elisabeth; Bignert, Anders [Swedish Museum of Natural History, P.O. Box 50007, 104 05 Stockholm (Sweden); Hoydal, Katrin S. [The Faroese Environment Agency, Traðagøta 38, P.O. Box 2048, FO-165 Argir, the Faroe Islands (Faroe Islands); Halldórsson, Halldór Pálmar [The University of Iceland´s Research Centre in Sudurnes, Gardvegi 1, 245 Sandgerdi (Iceland)

    2014-09-15

    As the ice cap of the Arctic diminishes due to global warming, the polar sailing route will be open larger parts of the year. These changes are likely to increase the pollution load on the pristine Arctic due to large vessel traffic from specific contaminant groups, such as polycyclic aromatic hydrocarbons (PAHs). A well-documented baseline for PAH concentrations in the biota in the remote regions of the Nordic Seas and the sub-Arctic is currently limited, but will be vital in order to assess future changes in PAH contamination in the region. Blue mussels (Mytilus edulis) were collected from remote sites in Greenland, Iceland, the Faroe Islands, Norway and Sweden as well as from urban sites in the same countries for comparison. Cod (Gadus morhua) was caught north of Iceland and along the Norwegian coast. Sixteen priority PAH congeners and the inorganic trace elements arsenic, cadmium, mercury and lead were analysed in the blue mussel samples as well as PAH metabolites in cod bile. Σ{sub 16}PAHs ranged from 28 ng/g dry weight (d.w.) (Álftafjörður, NW Iceland) to 480 ng/g d.w. (Ísafjörður, NW Iceland). Mussel samples from Mjóifjörður, East Iceland and Maarmorilik, West Greenland, contained elevated levels of Σ{sub 16}PAHs, 370 and 280 ng/g d.w., respectively. Levels of inorganic trace elements varied with highest levels of arsenic in mussels from Ísafjörður, Iceland (79 ng/g d.w.), cadmium in mussels from Mjóifjörður, Iceland (4.3 ng/g d.w.), mercury in mussels from Sørenfjorden, Norway (0.23 ng/g d.w.) and lead in mussels from Maarmorilik, Greenland (21 ng/g d.w.). 1-OH-pyrene was only found above limits of quantification (0.5 ng/mL) in samples from the Norwegian coast, ranging between 44 and 140 ng/ml bile. Generally, PAH levels were low in mussels from the remote sites investigated in the study, which indicates limited current effect on the environment. - Highlights: • Low levels of PAHs in blue mussels from remote areas of the Arctic. • Low

  11. Energy and environment. Annual report, 1975

    Energy Technology Data Exchange (ETDEWEB)

    Barton, R.G.; Lizama, L.R. (eds.)

    1976-01-01

    Progress is reported on the following programs: geothermal and geosciences; controlled thermonuclear research; chemical processing; instrument development; environment; energy use and conservation; energy analysis; and engineering sciences.

  12. Indoor Environment Program. 1992 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    Daisey, J.M.

    1993-06-01

    This paper reports progress during the year 1992 in the Indoor Environment Program in the Energy and Environment Division of Lawrence Berkeley Laboratory. Studies in the following areas are reported: energy performance and ventilation in buildings; physical and chemical characterization of indoor air pollutants; indoor radon; indoor air quality; exposure to indoor air pollutants and risk analysis. Pollutants of particular interest include: radon; volatile, semi-volatile and particulate organic compounds; and combustion emissions including environmental tobacco smoke, carbon monoxide, and nitrogen oxides.

  13. What matters 2010. Annual report of the Federal Environment Agency

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-04-27

    The annual report under consideration of the Federal Environment Agency (Dessau-Rosslau, Federal Republic of Germany) reports on the following themes: (1) Future mobility - Today's best investment; (2) Environmental protection - A barrier to investment for agriculture ?; (3) Emissions trading - The engine of climate policy ?; (4) The Federal Environment Agency (Departmental research, credo, organisation, data and facts, publications).

  14. Indoor environment program - 1995 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Daisey, J.M.

    1996-06-01

    Buildings use approximately one-third of the energy consumed in the United States. The potential energy savings derived from reduced infiltration and ventilation in buildings are substantial, since energy use associated with conditioning and distributing ventilation air is about 5.5 EJ per year. However, since ventilation is the dominant mechanism for removing pollutants from indoor sources, reduction of ventilation can have adverse effects on indoor air quality, and on the health, comfort, and productivity of building occupants. The Indoor Environment Program in LBL`s Energy and Environment Division was established in 1977 to conduct integrated research on ventilation, indoor air quality, and energy use and efficiency in buildings for the purpose of reducing energy liabilities associated with airflows into, within, and out of buildings while maintaining or improving occupant health and comfort. The Program is part of LBL`s Center for Building Science. Research is conducted on building energy use and efficiency, ventilation and infiltration, and thermal distribution systems; on the nature, sources, transport, transformation, and deposition of indoor air pollutants; and on exposure and health risks associated with indoor air pollutants. Pollutants of particular interest include radon; volatile, semivolatile, and particulate organic compounds; and combustion emissions, including environmental tobacco smoke, CO, and NO{sub x}.

  15. Indoor environment program. 1994 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Daisey, J.M.

    1995-04-01

    Buildings use approximately one-third of the energy consumed in the United States. The potential energy savings derived from reduced infiltration and ventilation in buildings are substantial, since energy use associated with conditioning and distributing ventilation air is about 5.5 EJ per year. However, since ventilation is the dominant mechanism for removing pollutants from indoor sources, reduction of ventilation can have adverse effects on indoor air quality, and on the health, comfort, and productivity of building occupants. The Indoor Environment Program in LBL`s Energy and Environment Division was established in 1977 to conduct integrated research on ventilation, indoor air quality, and energy use and efficiency in buildings for the purpose of reducing energy liabilities associated with airflows into, within, and out of buildings while maintaining or improving occupant health and comfort. The Program is part of LBL`s Center for Building Science. Research is conducted on building energy use and efficiency, ventilation and infiltration, and thermal distribution systems; on the nature, sources, transport, transformation, and deposition of indoor air pollutants; and on exposure and health risks associated with indoor air pollutants. Pollutants of particular interest include radon; volatile, semivolatile, and particulate organic compounds; and combustion emissions, including environmental tobacco smoke, CO, and NO{sub x}.

  16. Microbial oxidation of arsenite in a subarctic environment: diversity of arsenite oxidase genes and identification of a psychrotolerant arsenite oxidiser

    Directory of Open Access Journals (Sweden)

    Walker Stephen R

    2010-07-01

    Full Text Available Abstract Background Arsenic is toxic to most living cells. The two soluble inorganic forms of arsenic are arsenite (+3 and arsenate (+5, with arsenite the more toxic. Prokaryotic metabolism of arsenic has been reported in both thermal and moderate environments and has been shown to be involved in the redox cycling of arsenic. No arsenic metabolism (either dissimilatory arsenate reduction or arsenite oxidation has ever been reported in cold environments (i.e. Results Our study site is located 512 kilometres south of the Arctic Circle in the Northwest Territories, Canada in an inactive gold mine which contains mine waste water in excess of 50 mM arsenic. Several thousand tonnes of arsenic trioxide dust are stored in underground chambers and microbial biofilms grow on the chamber walls below seepage points rich in arsenite-containing solutions. We compared the arsenite oxidisers in two subsamples (which differed in arsenite concentration collected from one biofilm. 'Species' (sequence richness did not differ between subsamples, but the relative importance of the three identifiable clades did. An arsenite-oxidising bacterium (designated GM1 was isolated, and was shown to oxidise arsenite in the early exponential growth phase and to grow at a broad range of temperatures (4-25°C. Its arsenite oxidase was constitutively expressed and functioned over a broad temperature range. Conclusions The diversity of arsenite oxidisers does not significantly differ from two subsamples of a microbial biofilm that vary in arsenite concentrations. GM1 is the first psychrotolerant arsenite oxidiser to be isolated with the ability to grow below 10°C. This ability to grow at low temperatures could be harnessed for arsenic bioremediation in moderate to cold climates.

  17. Indoor Environment Program 1990 annual report

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    Approximately 38% of the energy consumed in the United States is used in buildings. Because humans spend an average of 85% to 90% of their time indoors, energy usage by the buildings sector can have a significant impact on human comfort, health and productivity. To advance energy conservation technologies while maintaining indoor air quality, research in the Indoor Environment Program (IEP) is directed toward understanding relations between building energy (usage and technologies), indoor air quality, and human health, comfort and productivity. The IEP addresses the issue of optimizing the health, comfort and productivity of a building`s occupants while maintaining the building`s energy efficiency. However, because ventilation is the dominant mechanism for removing pollutants with indoor sources, reduced ventilation may produce undesirable effects on indoor air quality and on the health, comfort, and productivity of a building`s occupants. This issue is an important theme for the research of other research groups and projects within IEP.

  18. Indoor Environment Program 1990 annual report

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    Approximately 38% of the energy consumed in the United States is used in buildings. Because humans spend an average of 85% to 90% of their time indoors, energy usage by the buildings sector can have a significant impact on human comfort, health and productivity. To advance energy conservation technologies while maintaining indoor air quality, research in the Indoor Environment Program (IEP) is directed toward understanding relations between building energy (usage and technologies), indoor air quality, and human health, comfort and productivity. The IEP addresses the issue of optimizing the health, comfort and productivity of a building's occupants while maintaining the building's energy efficiency. However, because ventilation is the dominant mechanism for removing pollutants with indoor sources, reduced ventilation may produce undesirable effects on indoor air quality and on the health, comfort, and productivity of a building's occupants. This issue is an important theme for the research of other research groups and projects within IEP.

  19. Pristine Arctic: background mapping of PAHs, PAH metabolites and inorganic trace elements in the North-Atlantic Arctic and sub-Arctic coastal environment.

    Science.gov (United States)

    Jörundsdóttir, Hrönn Ólína; Jensen, Sophie; Hylland, Ketil; Holth, Tor Fredrik; Gunnlaugsdóttir, Helga; Svavarsson, Jörundur; Olafsdóttir, Ásdís; El-Taliawy, Haitham; Rigét, Frank; Strand, Jakob; Nyberg, Elisabeth; Bignert, Anders; Hoydal, Katrin S; Halldórsson, Halldór Pálmar

    2014-09-15

    As the ice cap of the Arctic diminishes due to global warming, the polar sailing route will be open larger parts of the year. These changes are likely to increase the pollution load on the pristine Arctic due to large vessel traffic from specific contaminant groups, such as polycyclic aromatic hydrocarbons (PAHs). A well-documented baseline for PAH concentrations in the biota in the remote regions of the Nordic Seas and the sub-Arctic is currently limited, but will be vital in order to assess future changes in PAH contamination in the region. Blue mussels (Mytilus edulis) were collected from remote sites in Greenland, Iceland, the Faroe Islands, Norway and Sweden as well as from urban sites in the same countries for comparison. Cod (Gadus morhua) was caught north of Iceland and along the Norwegian coast. Sixteen priority PAH congeners and the inorganic trace elements arsenic, cadmium, mercury and lead were analysed in the blue mussel samples as well as PAH metabolites in cod bile. Σ16PAHs ranged from 28 ng/g dry weight (d.w.) (Álftafjörður, NW Iceland) to 480 ng/g d.w. (Ísafjörður, NW Iceland). Mussel samples from Mjóifjörður, East Iceland and Maarmorilik, West Greenland, contained elevated levels of Σ16PAHs, 370 and 280 ng/g d.w., respectively. Levels of inorganic trace elements varied with highest levels of arsenic in mussels from Ísafjörður, Iceland (79 ng/g d.w.), cadmium in mussels from Mjóifjörður, Iceland (4.3 ng/g d.w.), mercury in mussels from Sørenfjorden, Norway (0.23 ng/g d.w.) and lead in mussels from Maarmorilik, Greenland (21 ng/g d.w.). 1-OH-pyrene was only found above limits of quantification (0.5 ng/mL) in samples from the Norwegian coast, ranging between 44 and 140 ng/ml bile. Generally, PAH levels were low in mussels from the remote sites investigated in the study, which indicates limited current effect on the environment. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Indoor Environment Program 1991 annual report

    Energy Technology Data Exchange (ETDEWEB)

    1992-10-01

    Approximately 38% of the energy consumed in the United States is used in buildings. Much of this energy can be saved by reducing buildings' air infiltration and ventilation, since the heat load associated with these processes is about 13 quads per year. However, because ventilation is the dominant mechanism for removing pollutants that originate indoors, reducing ventilation can cause undesirable side effects such as lowering indoor air quality and adversely affecting the health, comfort and productivity of building occupants. The purpose of this research is to increase the energy efficiency of buildings while maintaining or improving occupant health and comfort. The research explores energy use and efficiency of buildings; building ventilation and infiltration; the nature, sources, transport, transformation, and deposition of indoor air pollutants; and exposure and risk assessment for indoor air pollutants. Pollutants of particular interest include radon; volatile, semi-volatile and particulate organic compounds; and combustion emissions, including environmental tobacco smoke, CO, and NO[sub x]. The Program also conducts multidisciplinary studies on relationships between occupant health and comfort symptoms and factors within a building's environment. Air infiltration and ventilation rates are measured and modeled for residential and commercial buildings in order to understand energy transport and thermal losses from various components of building shells and ventilation systems. Methods for reducing energy losses are based on these studies. The effectiveness of various ventilation systems for pollutant removal is also investigated. Methods for characterizing ventilation and building energy use are developed for experimental and applied uses.

  1. Indoor Environment Program 1991 annual report

    Energy Technology Data Exchange (ETDEWEB)

    1992-10-01

    Approximately 38% of the energy consumed in the United States is used in buildings. Much of this energy can be saved by reducing buildings` air infiltration and ventilation, since the heat load associated with these processes is about 13 quads per year. However, because ventilation is the dominant mechanism for removing pollutants that originate indoors, reducing ventilation can cause undesirable side effects such as lowering indoor air quality and adversely affecting the health, comfort and productivity of building occupants. The purpose of this research is to increase the energy efficiency of buildings while maintaining or improving occupant health and comfort. The research explores energy use and efficiency of buildings; building ventilation and infiltration; the nature, sources, transport, transformation, and deposition of indoor air pollutants; and exposure and risk assessment for indoor air pollutants. Pollutants of particular interest include radon; volatile, semi-volatile and particulate organic compounds; and combustion emissions, including environmental tobacco smoke, CO, and NO{sub x}. The Program also conducts multidisciplinary studies on relationships between occupant health and comfort symptoms and factors within a building`s environment. Air infiltration and ventilation rates are measured and modeled for residential and commercial buildings in order to understand energy transport and thermal losses from various components of building shells and ventilation systems. Methods for reducing energy losses are based on these studies. The effectiveness of various ventilation systems for pollutant removal is also investigated. Methods for characterizing ventilation and building energy use are developed for experimental and applied uses.

  2. Fluxes of Methane and Carbon Dioxide from a Subarctic Lake

    DEFF Research Database (Denmark)

    Jammet, Mathilde Manon

    important for the lake annual emissions compared to the length of the period, as it turned the lake from a small summer CO2 sink into an annual source. Annual inter-annual variability was notable in the magnitude of the CH4 spring release and needs further investigation. The high temporal resolution......-out and the release of CH4 and CO2 was established. These results underline the crucial importance of shoulder seasons in the annual carbon emissions from seasonally frozen lakes. Overall, the lake was an important annual source of carbon to the atmosphere, partially compensating the higher, annual sink function......Ongoing climate warming is expected to affect the carbon functioning of subarctic ecosystems. Lakes and wetlands, which are common ecosystems of the high northern latitudes, are of utmost interest in this context because they exchange large amounts of the climate-forcing gases methane (CH4...

  3. Radioactive foodchains in the subarctic environment. Progress report, August 15, 1975--August 14, 1976. [/sup 137/Cs and /sup 239/Pu, /sup 240/Pu distribution

    Energy Technology Data Exchange (ETDEWEB)

    Miettinen, J K

    1976-05-01

    Cesium-137 is accumulated in the foodchain lichen-reindeer-man causing high body burdens in Lapps who have reindeer meat as staple food. A group of Finnish Lapps has been whole body counted for /sup 137/Cs annually since 1961. Results of the measurements made in April 1976 show 18 percent decrease in /sup 137/Cs body burdens from the previous year. A dietary study confirmed that there was no mentionable change in the total amount of reindeer meat consumed although winter consumption has slightly decreased and summer consumption increased in recent years. Plutonium analyses of stockpiled lichen and reindeer samples from 1960 to 1973 were begun in 1973; since then the sampling has continued. Lichen had 200 pCi per kg dry weight in 1963 to 1964, 100 pCi/kg in 1966 to 1970, 20 pCi/kg in 1973 to 1975. Biological half-time of plutonium in lichen is 2 years. Reindeer liver contained about 20 pCi per kg fresh weight in 1963, 2 pCi in 1973. The ratio of plutonium in liver to its lifelong total intake gave a lower limit to absorption in reindeer. Of bones, plutonium concentration is highest in teeth, medium high in sternum, vertebra and humerus, and lowest in solid long bones. Human autopsy samples gave for lungs 0.19 liver 0.02 and bone 0.09 pCi /sup 239/ /sup 240/Pu per kg of wet weight.

  4. Health, Safety, and Environment Division: Annual progress report 1987

    Energy Technology Data Exchange (ETDEWEB)

    Rosenthal, M.A. (comp.)

    1988-04-01

    The primary responsibility of the Health, Safety, and Environment (HSE) Division at the Los Alamos National Laboratory is to provide comprehensive occupational health and safety programs, waste processing, and environment protection. These activities are designed to protect the worker, the public, and the environment. Many disciplines are required to meet the responsibilities, including radiation protection, industrial hygiene, safety, occupational medicine, environmental science, epidemiology, and waste management. New and challenging health and safety problems arise occasionally from the diverse research and development work of the Laboratory. Research programs in HSE Division often stem from these applied needs. These programs continue but are also extended, as needed to study specific problems for the Department of Energy and to help develop better occupational health and safety practices.

  5. Energy and Environment Division, annual report FY 1980

    Energy Technology Data Exchange (ETDEWEB)

    Osowitt, M. (ed.)

    1981-07-01

    This report covers research in: energy analysis; energy efficiency studies; solar energy; chemical process; energy-efficient buildings; environmental pollutant studies; combustion research; laser spectroscopy and trace elements; and oil shale and coal research. An energy and environment personnel listing is appended. Separate projects are indexed individually for the database. (PSB)

  6. Glacierized headwater streams as aquifer recharge corridors, subarctic Alaska

    Science.gov (United States)

    Liljedahl, A. K.; Gädeke, A.; O'Neel, S.; Gatesman, T. A.; Douglas, T. A.

    2017-07-01

    Arctic river discharge has increased in recent decades although sources and mechanisms remain debated. Abundant literature documents permafrost thaw and mountain glacier shrinkage over the past decades. Here we link glacier runoff to aquifer recharge via a losing headwater stream in subarctic Interior Alaska. Field measurements in Jarvis Creek (634 km2), a subbasin of the Tanana and Yukon Rivers, show glacier meltwater runoff as a large component (15-28%) of total annual streamflow despite low glacier cover (3%). About half of annual headwater streamflow is lost to the aquifer (38 to 56%). The estimated long-term change in glacier-derived aquifer recharge exceeds the observed increase in Tanana River base flow. Our findings suggest a linkage between glacier wastage, aquifer recharge along the headwater stream corridor, and lowland winter discharge. Accordingly, glacierized headwater streambeds may serve as major aquifer recharge zones in semiarid climates and therefore contributing to year-round base flow of lowland rivers.

  7. Glacierized headwater streams as aquifer recharge corridors, subarctic Alaska

    Science.gov (United States)

    Lilledahl, Anna K.; Gadeke, Anne; O'Neel, Shad; Gatesman, T. A.; Douglas, T. A.

    2017-01-01

    Arctic river discharge has increased in recent decades although sources and mechanisms remain debated. Abundant literature documents permafrost thaw and mountain glacier shrinkage over the past decades. Here we link glacier runoff to aquifer recharge via a losing headwater stream in subarctic Interior Alaska. Field measurements in Jarvis Creek (634 km2), a subbasin of the Tanana and Yukon Rivers, show glacier meltwater runoff as a large component (15–28%) of total annual streamflow despite low glacier cover (3%). About half of annual headwater streamflow is lost to the aquifer (38 to 56%). The estimated long-term change in glacier-derived aquifer recharge exceeds the observed increase in Tanana River base flow. Our findings suggest a linkage between glacier wastage, aquifer recharge along the headwater stream corridor, and lowland winter discharge. Accordingly, glacierized headwater streambeds may serve as major aquifer recharge zones in semiarid climates and therefore contributing to year-round base flow of lowland rivers.

  8. Energy and environment annual report 1974. [Environmental Research programs

    Energy Technology Data Exchange (ETDEWEB)

    Blumstein, C. (ed.)

    1974-01-01

    Research in the Division's environmental science program includes air pollution, water pollution, and the effects of pollutants on man and natural ecosystems. Work has focused on the chemistry and physics of particle surfaces. Using the technique of electron spectroscopy for chemical analysis (ESCA), surface reactions of sulfur and nitrogen compounds have been studied, and results include the identification of new chemical forms of nitrogen on particle surfaces and evidence for the importance of particle surfaces in the catalysis of sulfur dioxide to sulfuric acid. The Division's work in water pollution has been devoted to the study of trace metals in the estuarine environment, especially in San Francisco Bay. Studies on the effect of dredging operations on trace metals in the Mare Island ship channel and on the distribution of cadmium in Bay sediments have been performed. Research has also been conducted on the distribution of trace elements between bound states on suspended particles and in solution in Bay waters. Research is being conducted on a variety of problems relating to effects of pollutants. Biological studies seeking to discover effects of specific environmental insults such as oxidants at the cellular level have been done, and epidemiological studies have been initiated on the impacts of trace metals on human health. Theoretical studies in an attempt to develop a basis for assessing the stability of ecological systems are also being undertaken.

  9. Annual review of energy and the environment. Volume 23

    Energy Technology Data Exchange (ETDEWEB)

    Socolow, R.H. [ed.] [Princeton Univ., NJ (United States); Anderson, D. [ed.] [Imperial College of Science, Technology, and Medicine, London (United Kingdom); Harte, J. [ed.] [Univ. of California, Berkeley, CA (United States)

    1998-12-31

    Thirteen papers are included in this volume. The titles and authors are: From Physics to Development Strategies by Jose Goldemberg; Rewards and Penalties of Monitoring the Earth by Charles D. Keeling; Science and Nonscience Concerning Human-Caused Climate Warming by J. D. Mahlman; Consumption of Materials in the United States, 1990--1995 by Grecia Matos and Lorie Wagner; Future Technologies for Energy-Efficient Iron and Steel Making by Jeroen de Beer, Ernst Worrell, and Kornelis Blok; The O{sub 2} Balance of the Atmosphere: A Tool for Studying the Fate of Fossil Fuel CO{sub 2} by Michael L. Bender, Mark Battle, and Ralph F. Keeling; Mexican Electric End-Use Efficiency: Experiences to Date by Rafael Friedmann and Claudia Sheinbaum; Drinking Water in Developing Countries by Ashok Gadgil; Engineering-Economic Studies of Energy Technologies to Reduce Greenhouse Gas Emissions: Opportunities and Challenges by Marilyn A. Brown, Mark D. Levine, Joseph P. Romm, Arthur H. Rosenfeld, and Jonathan G. Koomey; Climate Change Mitigation in the Energy and Forestry Sectors of Developing Countries by Jayant A. Sathaye and N. H. Ravindranath; Toward a Productive Divorce: Separating DOE Cleanups from Transition Assistance by M. Russell; Recycling Metals for the Environment by Iddo K. Wernick and Nickolas J. Themelis; and Environmentally Conscious Chemical Process Design by J. A. Cano-Ruiz and G. J. McRae.

  10. Remote Sensing Methods for Environmental Monitoring of Human Impact on sub-Arctic Ecosystems in Europe

    OpenAIRE

    Shipigina, Ekaterina

    2013-01-01

    The role and scale of human impact on the global environment is a question of special importance to the scientific community and the world as a whole. This impact has dramatically increased since the beginning of industrialisation, yet its understanding remains patchy. The sub-Arctic plays a central role in forming the global environment due to the vast territory of boreal forest and tundra. Severe climatic conditions make its ecosystems highly sensitive to any natural and human disturbances....

  11. Bacterial community structure and soil properties of a subarctic tundra soil in Council, Alaska.

    Science.gov (United States)

    Kim, Hye Min; Jung, Ji Young; Yergeau, Etienne; Hwang, Chung Yeon; Hinzman, Larry; Nam, Sungjin; Hong, Soon Gyu; Kim, Ok-Sun; Chun, Jongsik; Lee, Yoo Kyung

    2014-08-01

    The subarctic region is highly responsive and vulnerable to climate change. Understanding the structure of subarctic soil microbial communities is essential for predicting the response of the subarctic soil environment to climate change. To determine the composition of the bacterial community and its relationship with soil properties, we investigated the bacterial community structure and properties of surface soil from the moist acidic tussock tundra in Council, Alaska. We collected 70 soil samples with 25-m intervals between sampling points from 0-10 cm to 10-20 cm depths. The bacterial community was analyzed by pyrosequencing of 16S rRNA genes, and the following soil properties were analyzed: soil moisture content (MC), pH, total carbon (TC), total nitrogen (TN), and inorganic nitrogen (NH4+ and NO3-). The community compositions of the two different depths showed that Alphaproteobacteria decreased with soil depth. Among the soil properties measured, soil pH was the most significant factor correlating with bacterial community in both upper and lower-layer soils. Bacterial community similarity based on jackknifed unweighted unifrac distance showed greater similarity across horizontal layers than through the vertical depth. This study showed that soil depth and pH were the most important soil properties determining bacterial community structure of the subarctic tundra soil in Council, Alaska. © 2014 The Authors. FEMS Microbiology Ecology published by John Wiley & Sons Ltd on behalf of the Federation of European Microbiological Societies.

  12. Future climate change will favour non-specialist mammals in the (subarctics.

    Directory of Open Access Journals (Sweden)

    Anouschka R Hof

    Full Text Available Arctic and subarctic (i.e., [sub]arctic ecosystems are predicted to be particularly susceptible to climate change. The area of tundra is expected to decrease and temperate climates will extend further north, affecting species inhabiting northern environments. Consequently, species at high latitudes should be especially susceptible to climate change, likely experiencing significant range contractions. Contrary to these expectations, our modelling of species distributions suggests that predicted climate change up to 2080 will favour most mammals presently inhabiting (subarctic Europe. Assuming full dispersal ability, most species will benefit from climate change, except for a few cold-climate specialists. However, most resident species will contract their ranges if they are not able to track their climatic niches, but no species is predicted to go extinct. If climate would change far beyond current predictions, however, species might disappear. The reason for the relative stability of mammalian presence might be that arctic regions have experienced large climatic shifts in the past, filtering out sensitive and range-restricted taxa. We also provide evidence that for most (subarctic mammals it is not climate change per se that will threaten them, but possible constraints on their dispersal ability and changes in community composition. Such impacts of future changes in species communities should receive more attention in literature.

  13. 6th Annual Homeland Security and Defense Education Summit, Developing an Adaptive Homeland Security Environment

    OpenAIRE

    2013-01-01

    6th Annual Homeland Security and Defense Education Summit Developing an Adaptive Homeland Security Environment, Burlington, MA, September 26-28, 2013 2013 Summit Agenda Naval Postgraduate School Center for Homeland Defense and Security In Partnership With Northeastern University, Department of Homeland Security, Federal Emergency Management Agency, National Guard Homeland Security Institute, National Homeland Defense Foundation Naval Postgraduate School Center for Homeland Defense and S...

  14. Impacts of Climate Change Induced Vegetation Responses on BVOC Emissions from Subarctic Heath Ecosystems

    DEFF Research Database (Denmark)

    Valolahti, Hanna Maritta

    temperature has been regulating annual plant biomass production, but ongoing global warming is more pronounced in these regions than what the global average is. This may increase the importance of subarctic and arctic vegetation as a source of BVOC emissions in near future. This thesis aims to increase......The role of biogenic volatile organic compounds (BVOCs) affecting Earths’ climate system is one of the greatest uncertainties when modelling the global climate change. BVOCs presence in the atmosphere can have both positive and negative climate feedback mechanisms when they involve atmospheric...... the understanding of the controls of BVOC emissions from subarctic ecosystems under climate change by studying the responses to long-term manipulations from leaf level to small ecosystem scale. Leaf-level studies showed different anatomical responses for warming and shading manipulations between studied species...

  15. ENERGY EFFICIENT BUILDINGS PROGRAM. CHAPTER FROM THE ENERGY AND ENVIRONMENT DIVISION ANNUAL REPORT 1979

    Energy Technology Data Exchange (ETDEWEB)

    Authors, Various

    1979-12-01

    The research reported in this volume was undertaken during FY 1979 within the Energy & Environment Division of the Lawrence Berkeley Laboratory. This volume will comprise a section of the Energy & Environment Division 1979 Annual Report, to be published in the summer of 1980. Work reported relate to: thermal performance of building envelopes; building ventilation and indoor air quality; a computer program for predicting energy use in buildings; study focused specifically on inherently energy intensive hospital buildings; energy efficient windows and lighting; potential for energy conservation and savings in the buildings sector; and evaluation of energy performance standards for residential buildings.

  16. Sub-arctic hydrology and climate change : a case study of the Tana River Basin in Northern Fennoscandia

    NARCIS (Netherlands)

    Dankers, Rutger

    2002-01-01

    The most significant changes in climate, due to the well-known enhanced greenhouse effect, are generally expected to occur at northern high latitudes. Sub-arctic environments, that are dominated by the presence of a seasonal snow cover, may therefore be particularly sensitive to global warming. The

  17. Slow acidification of the winter mixed layer in the subarctic western North Pacific

    Science.gov (United States)

    Wakita, Masahide; Nagano, Akira; Fujiki, Tetsuichi; Watanabe, Shuichi

    2017-08-01

    We used carbon dioxide (CO2) system data collected during 1999-2015 to investigate ocean acidification at time series sites in the western subarctic region of the North Pacific Ocean. The annual mean pH at station K2 decreased at a rate of 0.0025 ± 0.0010 year-1 mostly in response to oceanic uptake of anthropogenic CO2. The Revelle factor increased rapidly (0.046 ± 0.022 year-1), an indication that the buffering capacity of this region of the ocean has declined faster than at other time series sites. In the western subarctic region, the pH during the winter decline at a slower rate of 0.0008 ± 0.0004 year-1. This was attributed to a reduced rate of increase of dissolved inorganic carbon (DIC) and an increase of total alkalinity (TA). The reduction of DIC increase was caused by the decline of surface water density associated with the pycnocline depression and the reduction of vertical diffusion flux from the upper pycnocline. These physical changes were probably caused by northward shrinkage of the western subarctic gyre and global warming. Meanwhile, the contribution of the density decline to the TA increase is canceled out by that of the reduced vertical diffusive flux. We speculated that the winter TA increase is caused mainly by the accumulation of TA due to the weakened calcification by organisms during the winter.

  18. Living in the city: urban environments shape the evolution of a native annual plant.

    Science.gov (United States)

    Yakub, Mohamed; Tiffin, Peter

    2017-05-01

    Urban environments are warmer, have higher levels of atmospheric CO 2 and have altered patterns of disturbance and precipitation than nearby rural areas. These differences can be important for plant growth and are likely to create distinct selective environments. We planted a common garden experiment with seeds collected from natural populations of the native annual plant Lepidium virginicum, growing in five urban and nearby rural areas in the northern United States to determine whether and how urban populations differ from those from surrounding rural areas. When grown in a common environment, plants grown from seeds collected from urban areas bolted sooner, grew larger, had fewer leaves, had an extended time between bolting and flowering, and produced more seeds than plants grown from seeds collected from rural areas. Interestingly, the rural populations exhibited larger phenotypic differences from one another than urban populations. Surprisingly, genomic data revealed that the majority of individuals in each of the urban populations were more closely related to individuals from other urban populations than they were to geographically proximate rural areas - the one exception being urban and rural populations from New York which were nearly identical. Taken together, our results suggest that selection in urban environments favors different traits than selection in rural environments and that these differences can drive adaptation and shape population structure. © 2016 John Wiley & Sons Ltd.

  19. Contrasting trends in hydrologic extremes for two sub-arctic catchments in northern Sweden - Does glacier melt matter?

    Science.gov (United States)

    Dahlke, H. E.; Lyon, S. W.; Stedinger, J. R.; Rosqvist, G.; Jansson, P.

    2012-04-01

    Climate warming in the high-latitude environments of Sweden is raising concerns about its impacts upon hydrology. In order to manage future water resources in these snowmelt-dominated high-latitude and altitude catchments there is a need to determine how climatic change will influence glacial meltwater rates and terrestrial hydrology. This uncertainty is particularly acute for hydrologic extremes (flood events) because understanding the frequency of such unusual events requires long records of observation not often available for high-latitude and altitude catchments. This study presents a statistical analysis of trends in the magnitude and timing of hydrologic extremes (flood events) and the mean summer (June-August) discharge in two sub-arctic catchments, Tarfalajokk and Abiskojokk, in northern Sweden. The catchments have different glacier covers of 30% and 1%, respectively. Statistically significant hydrologic trends (at the 5% level) were identified for both catchments on an annual and on a seasonal scale (3-months averages) using the Mann-Kendall trend test and were related to observed changes in the precipitation and air temperature. Both catchments showed a statistically significant increase in the annual mean air temperature over the comparison time period of 1985-2009 (Tarfalajokk & Abiskojokk pflood peaks and the mean summer discharge. Hydrologic trends indicated an amplification of the hydrologic response in the highly glaciated catchment and a dampening of the response in the non-glaciated catchment. The glaciated mountain catchment showed a statistically significant increasing trend in the mean summer discharge that is clearly correlated to the decrease in glacier mass balance and the increase in air temperature. However, the catchment showed also a significant increase in the flood magnitudes, which are clearly correlated to the occurrence of extreme precipitation events, indicating a shift of the dominant storm runoff mechanism towards rainfall

  20. Heat Pumps in Subarctic Areas

    DEFF Research Database (Denmark)

    Atlason, Reynir Smari; Oddsson, Gudmundur Valur; Unnthorsson, Runar

    2017-01-01

    Geothermal heat pumps use the temperature difference between inside and outside areas to modify a refrigerant, either for heating or cooling. Doing so can lower the need for external heating energy for a household to some extent. The eventual impact depends on various factors, such as the external...... source for heating or cooling and the temperature difference. The use of geothermal heat pumps, and eventual benefits has not been studied in the context of frigid areas, such as in Iceland. In Iceland, only remote areas do not have access to district heating from geothermal energy where households may...... the Icelandic energy authority for the analysis. Findings show that a majority of households (83%) used between 20 and 50 MWh annually prior to installing a heat pump system (mean = 37.8 MWh). On average, households used approximately 26 MWh after installing a heat pump. When installing a small pump (5 to 9 k...

  1. Trichinella in arctic, subarctic and temperate regions

    DEFF Research Database (Denmark)

    Kapel, C. M O

    1997-01-01

    and the human activity are all very important interacting factors affecting epidemiology. In Greenland, where only sylvatic trichinellosis is present, the high prevalence in wildlife appears closely connected with polar bear hunting. In the Scandinavian countries, the prevalence of both sylvatic and domestic......The transmission and occurrence of Trichinella spp according to the zoogeography of different climatic conditions, socioeconomy and human activity are discussed. Comparing arctic, subarctic and temperate regions, it appears that the species of Trichinella present, the composition of the fauna...... populations may have epidemiological importance in relation to the recent changes in production and infrastructure in these former Soviet states....

  2. Influence of snowfall and melt timing on tree growth in subarctic Eurasia

    Science.gov (United States)

    Vaganov, E. A.; Hughes, M. K.; Kirdyanov, A. V.; Schweingruber, F. H.; Silkin, P. P.

    1999-07-01

    The causes of a reduced sensitivity of high-latitude tree growth to variations in summer temperature for recent decades,, compared to earlier this century, are unknown. This sensitivity change is problematic, in that relationships between tree-ring properties and temperature are widely used for reconstructing past climate. Here we report an analysis of tree-ring and climate data from the forest-tundra zone, in combination with a mechanistic model of tree-ring growth, to argue that an increasing trend of winter precipitation over the past century in many subarctic regions led to delayed snow melt in these permafrost environments. As a result, the initiation of cambial activity (necessary for the formation of wood cells) has been delayed relative to the pre-1960 period in the Siberian subarctic. Since the early 1960s, less of the growth season has been during what had previously been the period of maximal growth sensitivity to temperature. This shift results not only in slower growth, but also in a reduced correlation between growth and temperature. Our results suggest that changes in winter precipitation should be considered in seeking explanations for observed changes in the timing of the `spring greening' of high-latitude forests, and should be taken into account in the study of the role of the Siberian subarctic forest in the global carbon cycle.

  3. Oceanography of the subarctic Pacific region, 1960-71

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report is on the oceanography of the subarctic Pacific region 1969-1971. The background of the project is summarized. Next, a review of physical oceanography...

  4. Year-round CH4 and CO2 flux dynamics in two contrasting freshwater ecosystems of the subarctic

    Directory of Open Access Journals (Sweden)

    M. Jammet

    2017-11-01

    Full Text Available Lakes and wetlands, common ecosystems of the high northern latitudes, exchange large amounts of the climate-forcing gases methane (CH4 and carbon dioxide (CO2 with the atmosphere. The magnitudes of these fluxes and the processes driving them are still uncertain, particularly for subarctic and Arctic lakes where direct measurements of CH4 and CO2 emissions are often of low temporal resolution and are rarely sustained throughout the entire year. Using the eddy covariance method, we measured surface–atmosphere exchange of CH4 and CO2 during 2.5 years in a thawed fen and a shallow lake of a subarctic peatland complex. Gas exchange at the fen exhibited the expected seasonality of a subarctic wetland with maximum CH4 emissions and CO2 uptake in summer, as well as low but continuous emissions of CH4 and CO2 throughout the snow-covered winter. The seasonality of lake fluxes differed, with maximum CO2 and CH4 flux rates recorded at spring thaw. During the ice-free seasons, we could identify surface CH4 emissions as mostly ebullition events with a seasonal trend in the magnitude of the release, while a net CO2 flux indicated photosynthetic activity. We found correlations between surface CH4 emissions and surface sediment temperature, as well as between diel CO2 uptake and diel solar input. During spring, the breakdown of thermal stratification following ice thaw triggered the degassing of both CH4 and CO2. This spring burst was observed in 2 consecutive years for both gases, with a large inter-annual variability in the magnitude of the CH4 degassing. On the annual scale, spring emissions converted the lake from a small CO2 sink to a CO2 source: 80 % of total annual carbon emissions from the lake were emitted as CO2. The annual total carbon exchange per unit area was highest at the fen, which was an annual sink of carbon with respect to the atmosphere. Continuous respiration during the winter partly counteracted the fen summer sink by accounting for

  5. Year-round CH4 and CO2 flux dynamics in two contrasting freshwater ecosystems of the subarctic

    Science.gov (United States)

    Jammet, Mathilde; Dengel, Sigrid; Kettner, Ernesto; Parmentier, Frans-Jan W.; Wik, Martin; Crill, Patrick; Friborg, Thomas

    2017-11-01

    Lakes and wetlands, common ecosystems of the high northern latitudes, exchange large amounts of the climate-forcing gases methane (CH4) and carbon dioxide (CO2) with the atmosphere. The magnitudes of these fluxes and the processes driving them are still uncertain, particularly for subarctic and Arctic lakes where direct measurements of CH4 and CO2 emissions are often of low temporal resolution and are rarely sustained throughout the entire year. Using the eddy covariance method, we measured surface-atmosphere exchange of CH4 and CO2 during 2.5 years in a thawed fen and a shallow lake of a subarctic peatland complex. Gas exchange at the fen exhibited the expected seasonality of a subarctic wetland with maximum CH4 emissions and CO2 uptake in summer, as well as low but continuous emissions of CH4 and CO2 throughout the snow-covered winter. The seasonality of lake fluxes differed, with maximum CO2 and CH4 flux rates recorded at spring thaw. During the ice-free seasons, we could identify surface CH4 emissions as mostly ebullition events with a seasonal trend in the magnitude of the release, while a net CO2 flux indicated photosynthetic activity. We found correlations between surface CH4 emissions and surface sediment temperature, as well as between diel CO2 uptake and diel solar input. During spring, the breakdown of thermal stratification following ice thaw triggered the degassing of both CH4 and CO2. This spring burst was observed in 2 consecutive years for both gases, with a large inter-annual variability in the magnitude of the CH4 degassing. On the annual scale, spring emissions converted the lake from a small CO2 sink to a CO2 source: 80 % of total annual carbon emissions from the lake were emitted as CO2. The annual total carbon exchange per unit area was highest at the fen, which was an annual sink of carbon with respect to the atmosphere. Continuous respiration during the winter partly counteracted the fen summer sink by accounting for, as both CH4 and CO2, 33

  6. Analyzing tree cores to detect petroleum hydrocarbon-contaminated groundwater at a former landfill site in the community of Happy Valley-Goose Bay, eastern Canadian subarctic

    DEFF Research Database (Denmark)

    Fonkwe, Merline L D; Trapp, Stefan

    2016-01-01

    This research examines the feasibility of analyzing tree cores to detect benzene, toluene, ethylbenzene, and m, p, o-xylene (BTEX) compounds and methyl tertiary-butyl ether (MTBE) in groundwater in eastern Canada subarctic environments, using a former landfill site in the remote community of Happ...

  7. World bank and the environment: A progress report, fiscal year 1993. Annual report; Banque mondiale et l`environnement

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-03-01

    This fourth annual report examines how well the World Bank`s environmental policies have worked during fiscal year 1993. It presents an agenda of actions that will help countries manage their environment better and link environmental protection with sustainable development. It describes ways to improve environmental impact studies of Bank-financed projects. The report notes the World Bank`s improved public communications network and increased cofinancing for environmental projects. The Bank`s work in implementing Global Environment Facility (GEF) policies and the Montreal Protocol is also reviewed.

  8. Conceptualising the interactive effects of climate change and biological invasions on subarctic freshwater fish.

    Science.gov (United States)

    Rolls, Robert J; Hayden, Brian; Kahilainen, Kimmo K

    2017-06-01

    Climate change and species invasions represent key threats to global biodiversity. Subarctic freshwaters are sentinels for understanding both stressors because the effects of climate change are disproportionately strong at high latitudes and invasion of temperate species is prevalent. Here, we summarize the environmental effects of climate change and illustrate the ecological responses of freshwater fishes to these effects, spanning individual, population, community and ecosystem levels. Climate change is modifying hydrological cycles across atmospheric, terrestrial and aquatic components of subarctic ecosystems, causing increases in ambient water temperature and nutrient availability. These changes affect the individual behavior, habitat use, growth and metabolism, alter population spawning and recruitment dynamics, leading to changes in species abundance and distribution, modify food web structure, trophic interactions and energy flow within communities and change the sources, quantity and quality of energy and nutrients in ecosystems. Increases in temperature and its variability in aquatic environments underpin many ecological responses; however, altered hydrological regimes, increasing nutrient inputs and shortened ice cover are also important drivers of climate change effects and likely contribute to context-dependent responses. Species invasions are a complex aspect of the ecology of climate change because the phenomena of invasion are both an effect and a driver of the ecological consequences of climate change. Using subarctic freshwaters as an example, we illustrate how climate change can alter three distinct aspects of species invasions: (1) the vulnerability of ecosystems to be invaded, (2) the potential for species to spread and invade new habitats, and (3) the subsequent ecological effects of invaders. We identify three fundamental knowledge gaps focused on the need to determine (1) how environmental and landscape characteristics influence the

  9. The evolution of an annual life cycle in killifish: adaptation to ephemeral aquatic environments through embryonic diapause.

    Science.gov (United States)

    Furness, Andrew I

    2016-08-01

    An annual life cycle is characterized by growth, maturity, and reproduction condensed into a single, short season favourable to development, with production of embryos (seeds, cysts, or eggs) capable of surviving harsh conditions which juveniles or adults cannot tolerate. More typically associated with plants in desert environments, or temperate-zone insects exposed to freezing winters, the evolution of an annual life cycle in vertebrates is fairly novel. Killifish, small sexually dimorphic fishes in the Order Cyprinodontiformes, have adapted to seasonally ephemeral water bodies across much of Africa and South America through the independent evolution of an annual life history. These annual killifish produce hardy desiccation-resistant eggs that undergo diapause (developmental arrest) and remain buried in the soil for long periods when fish have perished due to the drying of their habitat. Killifish are found in aquatic habitats that span a continuum from permanent and stable to seasonal and variable, thus providing a useful system in which to piece together the evolutionary history of this life cycle using natural comparative variation. I first review adaptations for life in ephemeral aquatic environments in killifish, with particular emphasis on the evolution of embryonic diapause. I then bring together available evidence from a variety of approaches and provide a scenario for how this annual life cycle evolved. There are a number of features within Aplocheiloidei killifish including their inhabitation of marginal or edge aquatic habitat, their small size and rapid attainment of maturity, and egg properties that make them particularly well suited to the colonization of ephemeral waters. © 2015 Cambridge Philosophical Society.

  10. Alien Roadside Species More Easily Invade Alpine than Lowland Plant Communities in a Subarctic Mountain Ecosystem

    Science.gov (United States)

    Lembrechts, Jonas J.; Milbau, Ann; Nijs, Ivan

    2014-01-01

    Effects of roads on plant communities are not well known in cold-climate mountain ecosystems, where road building and development are expected to increase in future decades. Knowledge of the sensitivity of mountain plant communities to disturbance by roads is however important for future conservation purposes. We investigate the effects of roads on species richness and composition, including the plant strategies that are most affected, along three elevational gradients in a subarctic mountain ecosystem. We also examine whether mountain roads promote the introduction and invasion of alien plant species from the lowlands to the alpine zone. Observations of plant community composition were made together with abiotic, biotic and anthropogenic factors in 60 T-shaped transects. Alpine plant communities reacted differently to road disturbances than their lowland counterparts. On high elevations, the roadside species composition was more similar to that of the local natural communities. Less competitive and ruderal species were present at high compared with lower elevation roadsides. While the effects of roads thus seem to be mitigated in the alpine environment for plant species in general, mountain plant communities are more invasible than lowland communities. More precisely, relatively more alien species present in the roadside were found to invade into the surrounding natural community at high compared to low elevations. We conclude that effects of roads and introduction of alien species in lowlands cannot simply be extrapolated to the alpine and subarctic environment. PMID:24586947

  11. DECOMPOSITION OF SUB-ARCTIC PLANTS WITH DIFFERING NITROGEN ECONOMIES: A FUNCTIONAL ROLE FOR HEMIPARASITES

    DEFF Research Database (Denmark)

    Quested, H.M.; Cornelissen, J.H.C.; Press, M.C.

    2003-01-01

    in these processes, a comparison of leaf and litter tissue quality, nitrogen (N) resorption, and decomposability with those of a wide range of other plant groups (involving a total of 72 species and including other groups with access to alternative nutrient sources, such as nitrogen fixers and carnivorous plants...... and perennial hemiparasite litter contained, on average, 3.1% and 1.9% N, respectively, compared with 0.77–1.1% for groups without a major alternative N source. Hemiparasite litter lost significantly more mass during decomposition than many, but not all, co-occurring species. These results were combined...... with those of a litter trapping experiment to assess the potential impact of hemiparasites on nutrient cycling. The common sub-arctic hemiparasite Bartsia alpina was estimated to increase the total annual N input from litter to the soil by 42% within 5 cm of its stems, and by 53% across a site with a Bartsia...

  12. Nitrogen fixation, denitrification, and ecosystem nitrogen pools in relation to vegetation development in the Subarctic

    DEFF Research Database (Denmark)

    Sørensen, Pernille Lærkedal; Jonasson, Sven Evert; Michelsen, Anders

    2006-01-01

    Nitrogen (N) fixation, denitrification, and ecosystem pools of nitrogen were measured in three subarctic ecosystem types differing in soil frost-heaving activity and vegetation cover. N2-fixation was measured by the acetylene reduction assay and converted to absolute N ecosystem input by estimates...... measurements of temperature, light, and soil moisture. Nitrogen fixation rate was high with seasonal input estimated at 1.1 g N m2 on frostheaved sorted circles, which was higher than the total plant N content and exceeded estimated annual plant N uptake several-fold but was lower than the microbial N content...... of conversion factors between acetylene reduction and 15N incorporation. One aim was to relate nitrogen fluxes and nitrogen pools to the mosaic of ecosystem types of different stability common in areas of soil frost movements. A second aim was to identify abiotic controls on N2-fixation by simultaneous...

  13. Responses of vegetation and soil microbial communities to warming and simulated herbivory in a subarctic heath

    DEFF Research Database (Denmark)

    Rinnan, Riikka; Stark, Sari; Tolvanen, Anne

    2009-01-01

    setup of the International Tundra Experiment (ITEX). Wounding of the dominant deciduous dwarf shrub Vaccinium myrtillus L. to simulate herbivory was carried out annually. We measured vegetation cover in 2003 and 2007, soil nutrient concentrations in 2003 and 2006, soil microbial respiration in 2003......Climate warming increases the cover of deciduous shrubs in arctic ecosystems and herbivory is also known to have a strong influence on the biomass and composition of vegetation. However, research combining herbivory with warming is largely lacking. Our study describes how warming and simulated...... herbivory affect vegetation, soil nutrient concentrations and soil microbial communities after 10-13 years of exposure. 2 We established a factorial warming and herbivory-simulation experiment at a subarctic tundra heath in Kilpisj rvi, Finland, in 1994. Warming was carried out using the open-top chamber...

  14. Acetaldehyde in the Alaskan subarctic snowpack

    Directory of Open Access Journals (Sweden)

    F. Domine

    2010-02-01

    Full Text Available Acetaldehyde is a reactive intermediate in hydrocarbon oxidation. It is both emitted and taken up by snowpacks and photochemical and physical processes are probably involved. Understanding the reactivity of acetaldehyde in snow and its processes of physical and chemical exchanges requires the knowledge of its incorporation mechanism in snow crystals. We have performed a season-long study of the evolution of acetaldehyde concentrations in the subarctic snowpack near Fairbanks (65° N, central Alaska, which is subjected to a vigorous metamorphism due to persistent elevated temperature gradients in the snowpack, between 20 and 200° C m−1. The snowpack therefore almost entirely transforms into depth hoar. We have also analyzed acetaldehyde in a manipulated snowpack where temperature gradients were suppressed. Snow crystals there transformed much more slowly and their original shapes remained recognizable for months. The specific surface area of snow layers in both types of snowpacks was also measured. We deduce that acetaldehyde is not adsorbed onto the surface of snow crystals and that most of the acetaldehyde is probably not dissolved in the ice lattice of the snow crystals. We propose that most of the acetaldehyde measured is either trapped or dissolved within organic aerosol particles trapped in snow, or that acetaldehyde is formed by the hydrolysis of organic precursors contained in organic aerosols trapped in the snow, when the snow is melted for analysis. These precursors are probably aldehyde polymers formed within the aerosol particles by acid catalysis, but might also be biological molecules. In a laboratory experiment, acetaldehyde-di-n-hexyl acetal, representing a potential acetaldehyde precursor, was subjected to our analytical procedure and reacted to form acetaldehyde. This confirms our suggestion that acetaldehyde detected in snow could be produced during the melting of snow for analysis.

  15. Subarctic physicochemical weathering of serpentinized peridotite

    Science.gov (United States)

    Ulven, O. I.; Beinlich, A.; Hövelmann, J.; Austrheim, H.; Jamtveit, B.

    2017-06-01

    Frost weathering is effective in arctic and subarctic climate zones where chemical reactions are limited by the reduced availability of liquid water and the prevailing low temperature. However, small scale mineral dissolution reactions are nevertheless important for the generation of porosity by allowing infiltration of surface water with subsequent fracturing due to growth of ice and carbonate minerals. Here we combine textural and mineralogical observations in natural samples of partly serpentinized ultramafic rocks with a discrete element model describing the fracture mechanics of a solid when subject to pressure from the growth of ice and carbonate minerals in surface-near fractures. The mechanical model is coupled with a reaction-diffusion model that describes an initial stage of brucite dissolution as observed during weathering of serpentinized harzburgites and dunites from the Feragen Ultramafic Body (FUB), SE-Norway. Olivine and serpentine are effectively inert at relevant conditions and time scales, whereas brucite dissolution produces well-defined cm to dm thick weathering rinds with elevated porosity that allows influx of water. Brucite dissolution also increases the water saturation state with respect to hydrous Mg carbonate minerals, which are commonly found as infill in fractures in the fresh rock. This suggests that fracture propagation is at least partly driven by carbonate precipitation. Dissolution of secondary carbonate minerals during favorable climatic conditions provides open space available for ice crystallization that drives fracturing during winter. Our model reproduces the observed cm-scale meandering fractures that propagate into the fresh part of the rock, as well as dm-scale fractures that initiate the breakup of larger domains. Rock disintegration increases the reactive surface area and hence the rate of chemical weathering, enhances transport of dissolved and particulate matter in the weathering fluid, and facilitates CO2 uptake by

  16. Variable Trends in High Peak Flow Generation Across the Swedish Sub-Arctic

    Science.gov (United States)

    Matti, B.; Dahlke, H. E.; Lyon, S. W.

    2015-12-01

    There is growing concern about increased frequency and severity of floods and droughts globally in recent years. Improving knowledge on the complexity of hydrological systems and their interactions with climate is essential to be able to determine drivers of these extreme events and to predict changes in these drivers under altered climate conditions. This is particularly true in cold regions such as the Swedish Sub-Arctic where independent shifts in both precipitation and temperature can have significant influence on extremes. This study explores changes in the magnitude and timing of the annual maximum daily flows in 18 Swedish sub-arctic catchments. The Mann-Kendall trend test was used to estimate changes in selected hydrological signatures. Further, a flood frequency analysis was conducted by fitting a Gumbel (Extreme Value type I) distribution whereby selected flood percentiles were tested for stationarity using a generalized least squares regression approach. Our results showed that hydrological systems in cold climates have complex, heterogeneous interactions with climate. Shifts from a snowmelt-dominated to a rainfall-dominated flow regime were evident with all significant trends pointing towards (1) lower flood magnitudes in the spring flood; (2) earlier flood occurrence; (3) earlier snowmelt onset; and (4) decreasing mean summer flows. Decreasing trends in flood magnitude and mean summer flows suggest permafrost thawing and are in agreement with the increasing trends in annual minimum flows. Trends in the selected flood percentiles showed an increase in extreme events over the entire period of record, while trends were variable under shorter periods. A thorough uncertainty analysis emphasized that the applied trend test is highly sensitive to the period of record considered. As such, no clear overall regional pattern could be determined suggesting that how catchments are responding to changes in climatic drivers is strongly influenced by their physical

  17. Pacific Northwest Laboratory annual report for 1987 to the Assistant Secretary for Environment, Safety, and Health: Part 5: Environment, safety, health, and quality assurance

    Energy Technology Data Exchange (ETDEWEB)

    Faust, L.G.; Steelman, B.L.; Selby, J.M.

    1988-02-01

    Part 5 of the 1987 Annual Report to the US Department of Energy's Assistant Secretary for Environment, Safety, and Health presents Pacific Northwest Laboratory's progress on work performed for the Office of Nuclear Safety, the Office of Environmental Guidance and Compliance, the Office of Environmental Audit, and the Office of National Environmental Policy Act Project Assistance. For each project, as identified by the Field Work Proposal, articles describe progress made during fiscal year 1987. Authors of these articles represent a broad spectrum of capabilities derived from five of the seven technical centers of the Laboratory, reflecting the interdisciplinary nature of the work.

  18. Selected References on Arctic and Subarctic Prehistory and Ethnology. Revised.

    Science.gov (United States)

    Fitzhugh, William, Comp.; Loring, Stephen, Comp.

    This bibliography provides an introduction to the current literature, in English, on arctic and subarctic prehistory and ethnology. Leads for further research will be found in section 1. Publications listed are not available from the Smithsonian Institution but copies may be found in larger libraries or obtained through inter-library loan.…

  19. Anurans in a Subarctic Tundra Landscape Near Cape Churchill, Manitoba

    Science.gov (United States)

    Reiter, M.E.; Boal, C.W.; Andersen, D.E.

    2008-01-01

    Distribution, abundance, and habitat relationships of anurans inhabiting subarctic regions are poorly understood, and anuran monitoring protocols developed for temperate regions may not be applicable across large roadless areas of northern landscapes. In addition, arctic and subarctic regions of North America are predicted to experience changes in climate and, in some areas, are experiencing habitat alteration due to high rates of herbivory by breeding and migrating waterfowl. To better understand subarctic anuran abundance, distribution, and habitat associations, we conducted anuran calling surveys in the Cape Churchill region of Wapusk National Park, Manitoba, Canada, in 2004 and 2005. We conducted surveys along ~l-km transects distributed across three landscape types (coastal tundra, interior sedge meadow-tundra, and boreal forest-tundra interface) to estimate densities and probabilities of detection of Boreal Chorus Frogs (Pseudacris maculata) and Wood Frogs (Lithobates sylvaticus). We detected a Wood Frog or Boreal Chorus Frog on 22 (87%) of 26 transects surveyed, but probability of detection varied between years and species and among landscape types. Estimated densities of both species increased from the coastal zone inland toward the boreal forest edge. Our results suggest anurans occur across all three landscape types in our study area, but that species-specific spatial patterns exist in their abundances. Considerations for both spatial and temporal variation in abundance and detection probability need to be incorporated into surveys and monitoring programs for subarctic anurans.

  20. TARA OCEANS: A Global Analysis of Oceanic Plankton Ecosystems (2013 DOE JGI Genomics of Energy and Environment 8th Annual User Meeting)

    Energy Technology Data Exchange (ETDEWEB)

    Karsenti, Eric [EMBL Heidelberg

    2013-03-01

    Eric Karsenti of EMBL delivers the closing keynote on "TARA OCEANS: A Global Analysis of Oceanic Plankton Ecosystems" at the 8th Annual Genomics of Energy & Environment Meeting on March 28, 2013 in Walnut Creek, Calif.

  1. Genomic Analysis of Natural Variation for Seed and Plant Size in Maize ( JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

    Energy Technology Data Exchange (ETDEWEB)

    Kaeppler, Shawn [University of Wisconsin, Madison

    2012-03-21

    Shawn Kaeppler from the University of Wisconsin-Madison on "Genomic Analysis of Biofuel Traits in Maize and Switchgrass" at the 7th Annual Genomics of Energy & Environment Meeting on March 21, 2012 in Walnut Creek, Calif

  2. Radioactive foodchains in the subarctic environment. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Miettinen, J K

    1979-09-01

    In a period of increasing body burdens this project elucidated in great detail the radioactivity of the diet and tissues of reindeer and of reindeer herding Lapps, who consume large amounts of reindeer muscle and other tissues. The detailed and precise results made possible accurate forecasts of the change of radioactivity on all trophic levels and in the critical items of the foodchains elucidated. The accurate and reliable forecasts were made possible by a detailed knowledge of all environmental and dietary factors involved. The reliable forecasts made possible correct early decisions regarding eventual application of protective measures for reduction of the extra dose from /sup 137/Cs to the population group submitted to the highest extra dose, the adult male reindeer herders. The decision made was: no protective measures were necessary or recommendable, although a few individuals' dose commitment from /sup 137/Cs in the body exceeded 350 mrem/y in 1965. Any protective measure which would have cast some doubt on the safety of reindeer meat as human food from radiation point of view could have jeopardized its markets. Since the Lapps' only income was reindeer meat their loss of income would have caused them much greater health hazards than the temporary extra radiation dose which would only grow to 1 rem/30 years. This project also elucidated the relatively high natural radiation dose Lapps have always received from /sup 210/Po (e.g. in genitals 2500 mrem/30 y). This nuclide is cumulated in lichen from natural fallout and becomes just like /sup 137/Cs enriched into reindeer (particularly its liver) and Lapps. /sup 210/Po approximately doubles the natural background dose of Lapps in comparison to non-reindeer consumers.

  3. Effects of Climate Change on the Freshwaters of Arctic and Subarctic North America

    Science.gov (United States)

    Rouse, Wayne R.; Douglas, Marianne S. V.; Hecky, Robert E.; Hershey, Anne E.; Kling, George W.; Lesack, Lance; Marsh, Philip; McDonald, Michael; Nicholson, Barbara J.; Roulet, Nigel T.; Smol, John P.

    1997-06-01

    Region 2 comprises arctic and subarctic North America and is underlain by continuous or discontinuous permafrost. Its freshwater systems are dominated by a low energy environment and cold region processes. Central northern areas are almost totally influenced by arctic air masses while Pacific air becomes more prominent in the west, Atlantic air in the east and southern air masses at the lower latitudes. Air mass changes will play an important role in precipitation changes associated with climate warming. The snow season in the region is prolonged resulting in long-term storage of water so that the spring flood is often the major hydrological event of the year, even though, annual rainfall usually exceeds annual snowfall. The unique character of ponds and lakes is a result of the long frozen period, which affects nutrient status and gas exchange during the cold season and during thaw. GCM models are in close agreement for this region and predict temperature increases as large as 4°C in summer and 9°C in winter for a 2 × CO2 scenario. Palaeoclimate indicators support the probability that substantial temperature increases have occurred previously during the Holocene. The historical record indicates a temperature increase of > 1°C in parts of the region during the last century. GCM predictions of precipitation change indicate an increase, but there is little agreement amongst the various models on regional disposition or magnitude. Precipitation change is as important as temperature change in determining the water balance. The water balance is critical to every aspect of hydrology and limnology in the far north. Permafrost close to the surface plays a major role in freshwater systems because it often maintains lakes and wetlands above an impermeable frost table, which limits the water storage capabilities of the subsurface. Thawing associated with climate change would, particularly in areas of massive ice, stimulate landscape changes, which can affect every aspect

  4. Epipelagic nekton of the North Pacific Subarctic and Transition Zones

    Science.gov (United States)

    Brodeur, Richard; McKinnell, Skip; Nagasawa, Kazuya; Pearcy, William; Radchenko, Vladimir; Takagi, Shogo

    1999-03-01

    During the 1980s and 1990s, scientific research cruises and commercial gillnet operations with scientific observers aboard were conducted throughout much of the Subarctic and Transition Zones of the North Pacific Ocean. These studies produced one of the most extensive databases ever collected on the relative species composition and trophic structure of epipelagic nekton of the Subarctic and Transition Zones in the North Pacific Ocean. Data from Japanese high-seas gillnet research surveys (1981-1991) were examined using multivariate analytical techniques to analyse community structure of nektonic cephalopods, elasmobranchs, and teleosts in the North Pacific Subarctic and Transition Zones during the summer months, emphasizing differences between the eastern and western Subarctic Gyres. Species diversity generally increased going from west to east, which was apparently associated with the greater range of temperatures in the east. Discriminant analysis was able to correctly classify about half the catch locations into their respective regions. Catches from multinational drift gillnet commercial fisheries operations in 1990-1991 mainly in the Transition Zone were also examined. Classification techniques were employed to determine species associations and multivariate analyses were used to examine relationships of these assemblages to environmental data. We found that some species are often captured in the same gillnet sets and form species associations that are distinct in ordination space, but these associations are loose and may vary appreciably from year to year. We review recent studies on the feeding habits and daily ration of the dominant species and construct food webs for the eastern and western Subarctic and Transition Zone systems emphasizing the role that nekton play in these pelagic ecosystems.

  5. SubArctic Oceans and Global Climate

    Science.gov (United States)

    Rhines, P. B.

    2004-12-01

    The passages connecting the Arctic Ocean with the Atlantic and Pacific, and their `mediterranean' basins, are focal points for the global meridional overturning circulation, and all of the climate impacts which this implies. It is also a difficult region to model accurately: the sensitivity of climate models to subpolar ocean dynamics is well-known. In this talk we stress the need to instrument and analyze the subpolar oceans, and some examples of sustained observations developing there. Results from satellite altimetry, recent Seaglider deployments from Greenland, and mooring arrays will be described. In particular we show the first Seaglider sections of hydrography and bio-optical profiles of the Labrador Sea (one of the first extended deployments of this autonomous undersea vehicle); we discuss the decline during the 1990s of the subpolar gyre circulation of the Atlantic from its great strength during the positive NAO period of the early 1990s, and its relevance to the salinity decline observed over a much longer period; we review observations of the flows at the Iceland-Scotland Ridge and Davis Strait, argued in terms of volume transport plots on the potential temperature/salinity plane; we display maps of the `convection resistance' (related to dynamic height) and its sensitivity to surface low-salinity water masses and their partition between shallow continental shelves and deep ocean. This is a particularly exciting time for climate studies, with fundamental properties of the atmosphere-ocean circulation under debate, even before one considers natural and human-induced variability. Is the four-decade long decline in subArctic salinity the result of increased hydrologic cycle, increased or altered Arctic outflow to the Atlantic, or slowing of the subpolar circulation? Is the basic intensity of the MOC more dependent on high-latitude buoyancy forcing, or wind- or tide-driven mixing in the upwelling branch, or possibly wind-stress at high latitude? Is the

  6. Environmental programs of the Department of Energy and Environment annual highlights

    Energy Technology Data Exchange (ETDEWEB)

    Manowitz, B

    1978-12-01

    Environmental Sciences is one of the four areas comprising the Department of Energy and Environment at Brookhaven National Laboratory. It carries out a wide range of activities in atmospheric sciences, environmental chemistry, oceanographic sciences, and land and freshwater environmental sciences. In general, these programs are concerned with identification and measurement of pollutants introduced into the environment by energy-related activities and the evaluation and prediction of the effects or potential effects of these pollutants on the environment. This highlights report for Environmental Programs covers the year 1978 and describes the objectives and funding levels of each of the programs, major accomplishments during the year, planned future activities, and current publications.

  7. EH&S annual report: Summary of activities Environment, Health and Safety Division, 1992

    Energy Technology Data Exchange (ETDEWEB)

    1994-03-01

    This report presents an overview of the environment, safety, and health program in operation at the Lawrence Berkeley Laboratory. description of research in environmental science, remediation, waste management, safety, health services, radiation assessment, and emergency plans are provided.

  8. Charbonnages de France. 1998 annual report - Environment; Charbonnages de France. Rapport annuel 1998 - Environnement

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-01

    This 1998 annual report of the Charbonnages de France group presents the environmental actions carried out by the group after the Kyoto summit for the reduction of greenhouse gases and the preservation of fossil resources: the goals of the group and its environmental strategy; the use of waste products (bagasse-coal-fueled power plants, recovery of methane from coal mines, valorization of coal washing wastes, valorization of fly-ashes in cement industry); the reduction of pollutant emissions (development of supercritical, combined and hybrid cycles, fluidized bed boilers, reduction of pollutants during the dismantling of shutdown installations); water preservation (processing of acid mine waters, purification of waters from coke factories, cleansing of abandoned sites); sites rehabilitation (backfilling of abandoned mines, soil cleansing of dismantled coal processing facilities, reinforcing of abandoned cavities, prevention of erosion of spoil heaps etc..); improvement of landscapes (rehabilitation, revegetation); research and innovation (hydrological and geological impact studies, soil cleansing processes, phyto-remediation..). (J.S.)

  9. Establishing the Role of Digital Repeat Photography in Understanding Phenology and Carbon Cycling in a Subarctic Peatland

    Science.gov (United States)

    Garnello, Anthony John

    In this thesis, I establish and explore the role of phenology in understanding the rapidly changing environment of a subarctic peatland. First, I demonstrate how digital repeat photography can be used to characterize and differentiate distinct plant communities using two years of images. Each habitat is composed of different plant functional groups, promoting the individualistic approach to characterization that near-earth remote sensing tools can provide. The camera-product Relative Greenness successfully characterized interannual variability in seasonal growth for each habitat type. Across habitats, there was a direct relationship between advancement of spring onset and active season growth though this overall pattern showed habitat-specific variance. The camera images were also useful in characterizing the flowering phenology of an eriophorum-rich fen habitat, for which a metric named Intensity was created. These results suggest that employment of phenology cameras in highly heterogeneous subarctic environments is a robust method to characterize phenology on a habitat to species scale. Next, I explored the role that this phenology product has in modeling Net Ecosystem Exchange (NEE) also measured at the field site. I hypothesized that the explanatory power of the phenology index, which is conceptually tied to a measure of photosynthetic capacity, would be tightly linked to the timescale it was used for: At sub-daily timescales, environmental forces would dominate, though when averaged over days to weekly scales, the biology represented through the camera index would be more influential. I show that at multiple time scales the environmental factors outperform the camera index when modeling NEE. Together, these studies begin to explore the applicability of phenology camera systems in subarctic environments.

  10. Pacific Northwest Laboratory annual report for 1989 to the Assistant Secretary for Environment, Safety, and Health - Part 5: Environment, Safety, Health, and Quality Assurance

    Energy Technology Data Exchange (ETDEWEB)

    Faust, L.G.; Doctor, P.G.; Selby, J.M.

    1990-04-01

    Part 5 of the 1989 Annual Report to the US Department of Energy's Assistant Secretary for Environment, Safety, and Health presents Pacific Northwest Laboratory's progress on work performed for the Office of Environmental Guidance and Compliance, the Office of Environmental Audit, the Office of National Environmental Policy Act Project Assistance, the Office of Nuclear Safety, the Office of Safety Compliance, and the Office of Policy and Standards. For each project, as identified by the Field Work Proposal, there is an article describing progress made during fiscal year 1989. Authors of these articles represent a broad spectrum of capabilities derived from five of the seven technical centers of the Laboratory, reflecting the interdisciplinary nature of the work. 35 refs., 1 fig.

  11. Development of wind turbines for safe operation in alpine environments - Annual report

    Energy Technology Data Exchange (ETDEWEB)

    Barber, S.; Abhari, R.

    2009-08-15

    Many favourable sites for wind farms, particularly in the Swiss Alps, are located in cold, wet regions where the build-up of ice is a risk and therefore limits the installation of wind turbines. The aim of this work is to quantify and understand in detail the effects of blade icing on wind turbine performance and to propose mitigation strategies. The project is unique in that it is carried out using a multi-disciplinary approach that combines (1) analysis of field data, (2) controlled experiments on a sub-scale wind turbine model and (3) 3D Computational Fluid Dynamics. In part (1) the wind data and full-scale wind turbine power and icing measurements from the Alpine Test Site Guetsch over one year are analysed. Icing on the blades is estimated to cause approximately a 2% loss in Annual Energy Production (AEP). Other losses due to the particular location of the turbine in complex terrain are found to reduce the expected AEP by up to 23%. These major losses must be further investigated in controlled experiments. The analysis of photographs of ice on the blades, alongside numerical simulations, enables five ice geometries to be defined for Guetsch atmospheric conditions (altitude: 2331 m above sea level). One further 'extreme' ice shape is also defined, which is representative of ice formed on wind turbines installed at lower altitude sites such as the Berne Jura (altitude: 800 to 1500 m). In part (2), experiments are undertaken in the new sub-scale wind turbine test facility at ETH Zuerich using a novel method to quantify performance. The defined ice shapes are attached to the blades and the performance compared. The five shapes representative of the ice formed at Guetsch are found to reduce the Annual Energy Production by up to 2%. However, the 'extreme' ice shape could result in a loss in Annual Energy Production of up to 17%. Furthermore, the presence of ice on the most outboard 5% of the blade is found to be key to performance. Ice removal or

  12. Spectral properties of subarctic plants for remote ecosystem assessment

    Science.gov (United States)

    Golubeva, Elena; Tutubalina, Olga; Rees, Gareth; Zimin, Mikhail; Mikheeva, Anna

    2014-05-01

    Multispectral and hyperspectral satellite images are increasingly used to identify properties of vegetation, its state, dynamics and productivity. Arctic vegetation is sensitive to changing habitat conditions related to both natural causes (in particular climatic trends), and human impact (both direct and indirect, e.g. associated with air, soil and water pollution). Change in the state of individual plants and of vegetation cover in general enables their use as indicators of natural and anthropogenic processes, manifested in satellite images through change of their spectral reflectance properties. These processes can be studied by identifying significant links between spectral properties of objects in satellite images and corresponding properties of plants, recorded in situ. We focus on the spectral signatures of subarctic plants dominating treeline ecotone ecosystems to assess the feasibility of mapping the spatial structure and dynamics of vegetation using multispectral and hyperspectral satellite imagery. Our model objects are tundra plants and ecosystems in both natural and technogenically disturbed environments in the central part of the Kola Peninsula, Russia. We conducted ground spectroradiometry with two spectroradiometers: ASD FieldSpec 3 Hi-res (350-2500 nm range with resolution from 3 to 10 nm) and SkyeInstruments SpectroSense 2+ (bands centred at 480, 550, 680, 840 nm, 50-130 nm wide) for samples of different species: Betula pubescens S.L., B. tortuosa, Picea abies, Betula nana, Ledum palustre, Vaccinium uligimosum, V. myrtillus, V. vitis-idaea, Empetrum hermaphroditum, Cetraria islandica (L), Flavocetraria nivalis (Cetraria nivalis), Alectoria ochroleuca, Cladonia arbuscula S.L., Hylocomium splendens and Pleurozium Shreberi. The results demonstrate the ability of green vegetation to selectively reflect solar radiation, depending on the species composition and state of the plants. Our results will be included in a spectral library of northern plants

  13. Bet hedging in desert winter annual plants: optimal germination strategies in a variable environment.

    Science.gov (United States)

    Gremer, Jennifer R; Venable, D Lawrence

    2014-03-01

    In bet hedging, organisms sacrifice short-term success to reduce the long-term variance in success. Delayed germination is the classic example of bet hedging, in which a fraction of seeds remain dormant as a hedge against the risk of complete reproductive failure. Here, we investigate the adaptive nature of delayed germination as a bet hedging strategy using long-term demographic data on Sonoran Desert winter annual plants. Using stochastic population models, we estimate fitness as a function of delayed germination and identify evolutionarily stable strategies for 12 abundant species in the community. Results indicate that delayed germination meets the criteria as a bet hedging strategy for all species. Density-dependent models, but not density-independent ones, predicted optimal germination strategies that correspond remarkably well with observed patterns. By incorporating naturally occurring variation in seed and seedling dynamics, our results present a rigorous test of bet hedging theory within the relevant environmental context. © 2014 John Wiley & Sons Ltd/CNRS.

  14. Annual Site Environment Report Summary Pamphlet, Sandia National Laboratories, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    None

    2010-01-01

    Sandia collects environmental data to determine and report the impact of existing SNL/NM operations on the environment. Sandia’s environmental programs include air and water quality, environmental monitoring and surveillance, and activities associated with the National Environmental Policy Act (NEPA). Sandia’s objective is to maintain compliance with federal, state, and local requirements, and to affect the corporate culture so that environmental compliance practices continue to be an integral part of operations.

  15. Summer (sub-arctic) versus winter (sub-tropical) production affects on spinach leaf bio-nutrients: Vitamins (C, E, Folate, K1, provitamin A), lutein, phenolics, and antioxidants

    Science.gov (United States)

    Comparison of spinach (Spinacia oleracea L.) cultivars Lazio and Samish grown during the summer solstice in the sub-arctic versus the winter solstice in the sub-tropics provided insight into interactions between plant environment (day length, light intensity, ambient temperatures), cultivar and leaf...

  16. Payment Of the New Mexico Environment Department- Hazardous Waste Bureau Annual Business and Generation Fees Calendar Year 2011

    Energy Technology Data Exchange (ETDEWEB)

    Juarez, Catherine L. [Los Alamos National Laboratory

    2012-08-31

    The purpose of this letter is to transmit to the New Mexico Environment Department-Hazardous Waste Bureau (NMED-HWB), the Los alamos National Laboratory (LANL) Annual Business and Generation Fees for calendar year 2011. These fees are required pursuant to the provisions of New Mexico Hazardous Waste Act, Chapter 74, Article 4, NMSA (as amended). The Laboratory's Fenton Hill Facility did not generate any hazardous waste during the entire year, and is not required to pay a fee for calendar year 2011. The enclosed fee represents the amount for a single facility owned by the Department of Energy and co-operated by the Los Alamos National Security, LLC (LANS).

  17. Soil Compressibility under Irrigated Perennial and Annual Crops in a Semi-Arid Environment

    Directory of Open Access Journals (Sweden)

    Rafaela Watanabe

    Full Text Available ABSTRACT In irrigated soils, a continuous state of high moisture reduces resistance of the soil to applied external forces, favouring compaction. The aim of this study was to evaluate the susceptibility to compaction of developed calcareous soils in irrigated annual and perennial cropping systems of the Apodi Plateau, located in the Brazilian semi-arid region. Four areas of irrigated crops were evaluated: banana after two (B2 and 15 (B15 years cultivation, pasture (P, and a corn and beans succession (MB, as well as the reference areas for soil quality and corresponding natural vegetation (NVB2, NVB15, NVP and NVMB. Samples were collected at layers of 0.00-0.10 and 0.20-0.30 m; and for B2 and B15, samples were collected in the row and inter-row spaces. The following properties were determined: degree of compactness (DC, preconsolidation pressure (σp, compression index (Cc, maximum density (ρmax, critical water content (WCcrit, total organic carbon (TOC and carbon of light organic matter (Clom. Mean values were compared by the t-test at 5, 10, 15 and 20 % probability. An increase was seen in DC at a layer of 0.20-0.30 m in MB (p<0.15, showing the deleterious effects of preparing the soil by ploughing and chiselling, together with the cumulative traffic of heavy machinery. The TOC had a greater influence on ρmax than the stocks of Clom. Irrigation caused a reduction in Cc, and there was no effect on σp at field capacity. The planting rows showed different behaviour for Cc, ρmax, and WCcrit,, and in general the physical properties displayed better conditions than the inter-row spaces. Values for σp and Cc showed that agricultural soils display greater load-bearing capacity and are less susceptible to compaction in relation to soils under natural vegetation.

  18. Adaptation in a variable environment: Phenotypic plasticity and bet-hedging during egg diapause and hatching in an annual killifish.

    Science.gov (United States)

    Furness, Andrew I; Lee, Kevin; Reznick, David N

    2015-06-01

    Two ways in which organisms adapt to variable environments are phenotypic plasticity and bet-hedging. Theory suggests that bet-hedging is expected to evolve in unpredictable environments for which reliable cues indicative of future conditions (or season length) are lacking. Alternatively, if reliable cues exist indicating future conditions, organisms will be under selection to produce the most appropriate phenotype -that is, adaptive phenotypic plasticity. Here, we experimentally test which of these modes of adaptation are at play in killifish that have evolved an annual life cycle. These fish persist in ephemeral pools that completely dry each season through the production of eggs that can remain in developmental arrest, or diapause, buried in the soil, until the following rainy season. Consistent with diversified bet-hedging (a risk spreading strategy), we demonstrate that the eggs of the annual killifish Nothobranchius furzeri exhibit variation at multiple levels-whether or not different stages of diapause are entered, for how long diapause is entered, and the timing of hatching-and this variation persists after controlling for both genetic and environmental sources of variation. However, we show that phenotypic plasticity is also present in that the proportion of eggs that enter diapause is influenced by environmental factors (temperature and light level) that vary seasonally. In nature there is typically a large parameter zone where environmental cues are somewhat correlated with seasonality, but not perfectly so, such that it may be advantageous to have a combination of both bet-hedging and plasticity. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  19. Earthworm impacts on organo-mineral interactions and soil carbon inventories in Fennoscandian boreal and sub-arctic landscapes

    Science.gov (United States)

    Wackett, Adrian; Yoo, Kyungsoo; Cameron, Erin; Klaminder, Jonatan

    2017-04-01

    Boreal and sub-arctic environments sustain some of the most pristine and fragile ecosystems in the world and house a disproportionate amount of the global soil carbon pool. Although the historical view of soil carbon turnover has focused on the intrinsic molecular structure of organic matter, recent work has highlighted the importance of stabilizing soil carbon on reactive mineral surfaces. However, the rates and mechanisms controlling these processes at high latitudes are poorly understood. Here we explored the biogeochemical impacts of deep-burrowing earthworm species on a range of Fennoscandian forest soils to investigate how earthworms impact soil carbon inventories and organo-mineral associations across boreal and sub-arctic landscapes. We sampled soils and earthworms at six sites spanning almost ten degrees latitude and encompassing a wide range of soil types and textures, permitting simultaneous consideration of how climate and mineralogy affect earthworm-mediated shifts in soil carbon dynamics. Across all sites, earthworms significantly decreased the carbon and nitrogen contents of the upper 10 cm, presumably through consumption of the humus layer and subsequent incorporation of the underlying mineral soil into upper organic horizons. Their mixing of humus and underlying soil also generally increased the proportion of mineral surface area occluded by organic matter, although the extent to which earthworms facilitate such organo-mineral interactions appears to be controlled by soil texture and mineralogy. This work indicates that quantitative measurements of mineral surface area and its extent of coverage by soil organic matter facilitate scaling up of molecular interactions between organic matter and minerals to the level of soil profiles and landscapes. Our preliminary data also strongly suggests that earthworms have profound effects on the fate of soil carbon and nitrogen in boreal and sub-arctic environments, highlighting the need for a better

  20. Impacts of Deforestation and Climate Variability on Terrestrial Evapotranspiration in Subarctic China

    Directory of Open Access Journals (Sweden)

    Yunjun Yao

    2014-10-01

    Full Text Available Although deforestation affects hydrological and climatic variables over tropical regions, its actual contributions to changes in evapotranspiration (ET over subarctic China remain unknown. To establish a quantitative relationship between deforestation and terrestrial ET variations, we estimated ET using a semi-empirical Penman (SEMI-PM algorithm driven by meteorological and satellite data at both local and regional scales. The results indicate that the estimated ET can be used to analyse the observed inter-annual variations. There is a statistically significant positive relationship between local-scale forest cover changes (∆F and annual ET variations (∆ET of the following form: ∆ET = 0.0377∆F – 2.11 (R2 = 0.43, p < 0.05. This relationship may be due to deforestation-induced increases in surface albedo and a reduction in the fractional vegetation cover (FVC. However, the El Niño/Southern Oscillation (ENSO, rather than deforestation, dominates the multi-decadal ET variability due to regional-scale wind speed changes, but the exact effects of deforestation and ENSO on ET are challenging to quantify.

  1. Carbon dioxide in Arctic and subarctic regions

    Energy Technology Data Exchange (ETDEWEB)

    Gosink, T. A.; Kelley, J. J.

    1981-03-01

    A three year research project was presented that would define the role of the Arctic ocean, sea ice, tundra, taiga, high latitude ponds and lakes and polar anthropogenic activity on the carbon dioxide content of the atmosphere. Due to the large physical and geographical differences between the two polar regions, a comparison of CO/sub 2/ source and sink strengths of the two areas was proposed. Research opportunities during the first year, particularly those aboard the Swedish icebreaker, YMER, provided additional confirmatory data about the natural source and sink strengths for carbon dioxide in the Arctic regions. As a result, the hypothesis that these natural sources and sinks are strong enough to significantly affect global atmospheric carbon dioxide levels is considerably strengthened. Based on the available data we calculate that the whole Arctic region is a net annual sink for about 1.1 x 10/sup 15/ g of CO/sub 2/, or the equivalent of about 5% of the annual anthropogenic input into the atmosphere. For the second year of this research effort, research on the seasonal sources and sinks of CO/sub 2/ in the Arctic will be continued. Particular attention will be paid to the seasonal sea ice zones during the freeze and thaw periods, and the tundra-taiga regions, also during the freeze and thaw periods.

  2. Annual highlights, Environmental Programs of the Department of Energy and Environment

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-12-01

    Brief summaries are presented of some 35 individual programs covering a wide range of activities in the atmospheric, oceanographic, and terrestrial ecology areas. In general, these programs are involved with the study of pollutants resulting from the production of energy and their effects or potential effects on the environment. Programs include meteorology and plume dispersion, with emphasis on tracing plumes from the tall stacks of fossil-fuel burning power plants, and implementation of MAP3S (the Multistate Atmospheric Power Production Pollution Study), including both field and modeling studies related to atmospheric pollutants in the Northeastern United States, the meteorology of the coastal land-sea interface, the development of long-distance tracer systems for following movements of air masses, the measurement of a series of pollutants at ambient levels in real time, and laboratory and field studies on the collection and behavior of aerosol particulates, including work on the speciation and quantification of sulfate particulates. The objective of programs in oceanographic sciences is to assess the potential impact of energy-related activities (reactor releases, oil spills, etc.) on the Northeast coastal zone and its biota. A capability for the study of environmental virology has been established. Another major program is the study of the effects of acid rain on forest ecosystems and on selected crops.

  3. LASER SPECTROSCOPY AND TRACE ELEMENT ANALYSIS Chapter from the Energy and Environment Division Annual Report 1980

    Energy Technology Data Exchange (ETDEWEB)

    Various, Authors

    1981-05-01

    In order to control pollutants resulting from energy production and utilization, adequate methods are required for monitoring the level of various substances often present at low concentrations. The Energy and Environment Division Applied Research in Laser Spectroscopy & Analytical Techniques Program is directed toward meeting these needs, Emphasis is on the development of physical methods, as opposed to conventional chemical analysis techniques. The advantages, now widely recognized, include ultra-high sensitivity coupled with minimal sample preparation. In some instances physical methods provide multi-parameter measurements which often provide the only means of achiev·ing the sensitivity necessary for the detection of trace contaminants. Work is reported in these areas: APPLIED PHYSICS AND LASER SPECTROSCOPY RESEARCH; MICROPROCESSOR CONTROLLER ANODIC STRIPPING VOLTAMETER FOR TRACE METALS ANALYSIS IN WATER; THE SURVEY OF INSTRUMENTATION FOR ENVIRONMENTAL MONITORING; THE POSSIBLE CHRONDRITIC NATURE OF THE DANISH CRETACEOUS~TERTIARY BOUNDARY; IMPROVEMENT OF THE SENSITIVITY AND PRECISION OF NEUTRON ACTIVATION ANALYSIS OF SOME ELEMENTS IN PLANKTON AND PLANKTONIC FISH; and SOURCES OF SOME SECONDARILY WORKED OBSIDIAN ARTIFACTS FROM TIKAL, GUATEMALA.

  4. Fourth annual workshop on management in basic and applied research environments

    Energy Technology Data Exchange (ETDEWEB)

    Bodnarczuk, M.W. [ed.

    1993-11-01

    The struggle to develop quality management concepts that ``map`` onto the cultural and work practices found in basic and applied research environments has been (for better or for worse) an attempt to differentiate basic and applied research from the nuclear industry. In the first (1990) edition of this ``Music Book`` proceedings, almost every laboratory that participated had a quality program that was traceable to, based on, influenced by, or in reaction to the nuclear quality standard ASME-NQA-1. This 1993 edition of the ``Music Book`` is very different in that almost every laboratory has developed a quality program that is based on, traceable to, or heavily influenced by DOE 5700.6C (Quality Assurance) and the DOE Standard; Implementation Guide for Quality Assurance Programs for Basic and Applied Research (DOE-ER-STD-6001-92). In order to construct a context for what follows and properly introduce the contents of this book, we want to briefly recount some of the highlights of the events that brought about this change, from the perspective of one who participated in the process.

  5. Carbon and nitrogen dynamics across a bedrock-regulated subarctic pH gradient

    Science.gov (United States)

    Tomczyk, N.; Heim, E. W.; Sadowsky, J.; Remiszewski, K.; Varner, R. K.; Bryce, J. G.; Frey, S. D.

    2014-12-01

    Bedrock geochemistry has been shown to influence landscape evolution due to nutrient limitation on primary production. There may also be less direct interactions between bedrock-derived chemicals and ecosystem function. Effects of calcium (Ca) and pH on soil carbon (C) and nitrogen (N) cycling have been shown in acid impacted forests o f North America. Understanding intrinsic factors that affect C and nutrient dynamics in subarctic ecosystems has implications for how these ecosystems will respond to a changing climate. How the soil microbial community allocates enzymes to acquire resources from the environment can indicate whether a system is nutrient or energy limited. This study examined whether bedrock geochemistry exerts pressure on nutrient cycles in the overlying soils. In thin, weakly developed soils, bedrock is the primary mineral material and is a source of vital nutrients. Nitrogen (N) and C are not derived from bedrock, but their cycling is still affected by reactions with geologically-derived chemicals. Our study sites near Abisko, Sweden (~68°N) were selected adjacent to five distinct bedrock outcrops (quartzite, slate, carbonate, and two different metasedimenty units). All sites were at a similar elevation (~700 m a.s.l.) and had similar vegetation (subarctic heath). Nutrient concentrations in bedrock and soils were measured in addition to soil microbial biomass and extracellular enzyme activity. We found a statistically significant correlation between soil Ca concentrations and soil pH (r = 0.88, p pH and the ratio of C-acquiring to N-acquiring enzyme activity (r = -0.89, p pH and soil C-to-N ratio (r = -0.76, p enzyme activity and soil C-to-N ratio (r = 0.78, p effect on soil pH.

  6. SOLAR ENERGY PROGRAM: CHAPTER FROM THE ENERGY AND ENVIRONMENT ANNUAL REPORT 1979

    Energy Technology Data Exchange (ETDEWEB)

    Authors, Various

    1980-10-01

    controller and to evaluate commercially available units. Research is continuing on 'passive' approaches to solar heating and cooling where careful considerations of architectural design, construction materials, and the environment are used to moderate a building's interior climate. Computer models of passive concepts are being developed in a collaborative project with Los Alamos Scientific Laboratory. These models will be incorporated into public domain building energy analysis computer programs to be used in systems studies and in the design of commercial buildings on a case study basis. The investigation of specific passive cooling methods is an ongoing project; for example, a process is being studied in which heat storage material would be cooled by radiation to the night sky, then provide 'coolness' to the building. The laboratory personnel involved in the solar cooling, controls, and passive projects are also providing technical support to the Solar Heating and Cooling Research and Development Branch of DOE in developing program plans, evaluating proposals, and making technical reviews of projects at other institutions and in industry. Low grade heat is a widespread energy resource that could make a significant contribution to energy needs if economical methods can be developed for converting it to useful work. Investigations continued this year on the feasibility of using the 'shape-memory' alloy, Nitinol, as a basis for constructing heat engines that could operate from energy sources such as solar heated water, industrial waste heat, geothermal brines, and ocean thermal gradients. Several projects are investigating longer-term possibilities for utilizing solar energy. One project involves the development of a new type of solar thermal receiver that would be placed at the focus of a central receiver system or a parabolic dish. The conversion of the concentrated sunlight to thermal energy would be accomplished by the absorption of the

  7. Omics in the Arctic: Genome-enabled Contributions to Carbon Cycle Research in High-Latitude Ecosystems (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

    Energy Technology Data Exchange (ETDEWEB)

    Wullschleger, Stan [ORNL

    2012-03-22

    Stan Wullschleger of Oak Ridge National Laboratory on "Omics in the Arctic: Genome-enabled Contributions to Carbon Cycle Research in High-Latitude Ecosystems" on March 22, 2012 at the 7th Annual Genomics of Energy & Environment Meeting in Walnut Creek, California.

  8. Applications of Genome-based Science in Shaping Citrus Industries of the World (JGI Seventh Annual User Meeting, 2012: Genomics of Energy and Environment)

    Energy Technology Data Exchange (ETDEWEB)

    Gmitter, Jr., Fred; Rokhsar, Dan

    2012-03-21

    Fred Gmitter from the University of Florida on "Applications of Genome-based Science in Shaping the Future of the World's Citrus Industries" at the 7th Annual Genomics of Energy & Environment Meeting on March 21, 2012 in Walnut Creek, California.

  9. In Situ Expression of Acidic and Thermophilic Carbohydrate Active Enzymes by Filamentous Fungi (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)

    Energy Technology Data Exchange (ETDEWEB)

    Mosier, Annika [Stanford University

    2012-03-22

    Annika Mosier, graduate student from Stanford University presents a talk titled "In Situ Expression of Acidic and Thermophilic Carbohydrate Active Enzymes by Filamentous Fungi" at the JGI User 7th Annual Genomics of Energy & Environment Meeting on March 22, 2012 in Walnut Creek, Calif

  10. Systematically enhanced subarctic Pacific stratification and nutrient utilization during glacials

    Science.gov (United States)

    Knudson, K. P.; Ravelo, A. C.

    2015-12-01

    The modern subarctic North Pacific is characterized as a high-nitrate, low-chlorophyll (HNLC) area, but evidence for increased nutrient utilization during the last glacial indicates that this region is highly dynamic. As such, this HNLC area is of particular interest in regard to understanding changes in the biological pump and carbon sequestration and predicting how biogeochemical processes will influence, or be influenced by, future climate change. While it has been suggested that changes in iron supply and/or ocean stratification could explain fluctuations in nutrient utilization and productivity in the subarctic Pacific, short records of nutrient utilization have previously hindered the evaluation of these potential mechanisms over long timescales. Here we present new, high-resolution records of bulk sediment δ15N from 0-1.2 Ma from Integrated Ocean Drilling Program Exp. 323 Site U1342, which are used to calculate Δδ15N (U1342 δ15Nbulk - ODP Site 1012 δ15Nbulk) as a nitrate utilization proxy. The unprecedented length and resolution of this new record allows us, for the first time, to determine orbital-scale systematic behavior in subarctic Pacific nutrient utilization over many glacial/interglacial cycles. Spectral analyses demonstrate that enhanced nutrient utilization was paced by climate on Milankovitch orbital cycles since the Mid-Pleistocene Transition (MPT; ~800 ka). Nitrate utilization maxima is statistically correlated with glacial maxima and enhanced dust/iron availability (represented by existing records of EPICA ice core dust, Southern Pacific Ocean sediment iron, and China loess) but shows low correlation to primary productivity, suggesting that stratification has systematically exerted an important control on subarctic Pacific nutrient utilization since the MPT. These findings imply that the presence of iron helped to change the region into a nitrate-limited, rather than iron-limited, region during glacials and that stratification, which

  11. Contrasting trends in floods for two sub-arctic catchments in northern Sweden – does glacier presence matter?

    Directory of Open Access Journals (Sweden)

    H. E. Dahlke

    2012-07-01

    Full Text Available Our understanding is limited to how transient changes in glacier response to climate warming will influence the catchment hydrology in the Arctic and Sub-Arctic. This understanding is particularly incomplete for flooding extremes because understanding the frequency of such unusual events requires long records of observation not often available for the Arctic and Sub-Arctic. This study presents a statistical analysis of trends in the magnitude and timing of flood extremes and the mean summer discharge in two sub-arctic catchments, Tarfala and Abisko, in northern Sweden. The catchments have different glacier covers (30% and 1%, respectively. Statistically significant trends (at the 5% level were identified for both catchments on an annual and on a seasonal scale (3-months averages using the Mann-Kendall trend test. Stationarity of flood records was tested by analyzing trends in the flood quantiles, using generalized least squares regression. Hydrologic trends were related to observed changes in the precipitation and air temperature, and were correlated with 3-months averaged climate pattern indices (e.g. North Atlantic oscillation. Both catchments showed a statistically significant increase in the annual mean air temperature over the comparison time period of 1985–2009 (Tarfala and Abisko p<0.01, but did not show significant trends in the total precipitation (Tarfala p = 0.91, Abisko p = 0.44. Despite the similar climate evolution over the studied period in the two catchments, data showed contrasting trends in the magnitude and timing of flood peaks and the mean summer discharge. Hydrologic trends indicated an amplification of the streamflow and flood response in the highly glacierized catchment and a dampening of the response in the non-glacierized catchment. The glacierized mountain catchment showed a statistically significant increasing trend in the flood magnitudes (p = 0.04 that is clearly correlated to the

  12. Contrasting trends in floods for two sub-arctic catchments in northern Sweden - does glacier presence matter?

    Science.gov (United States)

    Dahlke, H. E.; Lyon, S. W.; Stedinger, J. R.; Rosqvist, G.; Jansson, P.

    2012-07-01

    Our understanding is limited to how transient changes in glacier response to climate warming will influence the catchment hydrology in the Arctic and Sub-Arctic. This understanding is particularly incomplete for flooding extremes because understanding the frequency of such unusual events requires long records of observation not often available for the Arctic and Sub-Arctic. This study presents a statistical analysis of trends in the magnitude and timing of flood extremes and the mean summer discharge in two sub-arctic catchments, Tarfala and Abisko, in northern Sweden. The catchments have different glacier covers (30% and 1%, respectively). Statistically significant trends (at the 5% level) were identified for both catchments on an annual and on a seasonal scale (3-months averages) using the Mann-Kendall trend test. Stationarity of flood records was tested by analyzing trends in the flood quantiles, using generalized least squares regression. Hydrologic trends were related to observed changes in the precipitation and air temperature, and were correlated with 3-months averaged climate pattern indices (e.g. North Atlantic oscillation). Both catchments showed a statistically significant increase in the annual mean air temperature over the comparison time period of 1985-2009 (Tarfala and Abisko pflood peaks and the mean summer discharge. Hydrologic trends indicated an amplification of the streamflow and flood response in the highly glacierized catchment and a dampening of the response in the non-glacierized catchment. The glacierized mountain catchment showed a statistically significant increasing trend in the flood magnitudes (p = 0.04) that is clearly correlated to the occurrence of extreme precipitation events. It also showed a significant increase in mean summer discharge (p = 0.0002), which is significantly correlated to the decrease in glacier mass balance and the increase in air temperature (p = 0.08). Conversely, the non-glacierized catchment showed a

  13. Subarctic warming: Results from the global treeline project

    Energy Technology Data Exchange (ETDEWEB)

    Siren, G.; Shen, S.

    1996-12-31

    The authors reported last year at the 6th Global Warming Science and Policy Conference (GW6), April 3--6, 1995, San Francisco USA, the Global Treeline Project (BLECSCO) has definitively established the northward movement in the 20th century of the northernmost limit for pine trees in Finland. this movement is due to climate warming. The Finnish Forest Research Institute has been working on this problem between 1951 and 1996. The authors have observed over half a century the movements of the coniferous treeline. The subarctic pine tree line is used as a permanent bioindicator of climate change. The dynamic pine tree line in the subarctic of Finland serves as a reliable indicator of expected climate change in the future as well as of climatic fluctuations in the past. The FFRI has tracked comprehensively seed year frequencies, performed dendrochronological studies, fire studies, and ecological studies since the abundant seed year of 1948--50 to the present, and discovered that climate change has favored the northward movement of the pine limit. The authors report the detailed scientific methodology, data, and conclusions.

  14. Examining the relationship between mercury and organic matter in lake sediments along a latitudinal transect in subarctic Canada

    Science.gov (United States)

    Galloway, Jennifer M.; Sanei, Hamed; Parsons, Michael; Swindles, Graeme T.; Macumber, Andrew L.; Patterson, R. Timothy; Palmer, Michael; Falck, Hendrik

    2016-04-01

    The accumulation of Hg in aquatic environments at both high and low latitudes can be controlled by organic matter through algal scavenging, thus complicating the interpretation of historical Hg profiles in lake sediments1,2,3. However, other recent studies suggest that algal scavenging is not important in governing Hg flux to sediments4, in some cases because of dilution by inorganic materials5. This study examines relationships between Hg and organic matter (OM) in over 100 lakes located between 60.5 and 65.4 °N and crossing the latitudinal tree-line in subarctic Canada. The latitudinal gradient approach in our study offers an opportunity to better understand climate and environmental controls on OM accumulation and its role in influencing Hg deposition in subarctic lacustrine environments. We used Rock Eval 6 pyrolysis to determine total organic carbon (TOC%), S1 (soluble OM consisting of degradable lipids and algal pigments), S2 (OM derived from highly aliphatic biomacromolecule structure of algal cell walls), and S3 (OM dominated by carbohydrates, lignins, and plant materials). Total Hg in sediments was measured using thermal decomposition, amalgamation, and atomic absorption spectrophotometry. In these lake sediments, S2 composes the majority of TOC (Pearson's r = 0.978, pEnviron Sci Technol 41: 5259-65. 3Wu, F., Zu, L., Liao, H., Guo, F., Zhao, X., Giesy, J. 2013. Relationship between mercury and organic carbon in sediment cores from Lakes Qinghai and Chenghai, China. J Soils Sediments 13: 1084-1092.4Kirk, J.L., Muir, D.C.G., Antoniades, D., Douglas, M.S.V., Evans, M.S., Jackson, T.A., Kling, H., Lamoureux, S., Lim, D.S.S., Pienitz, R., Smol, J.P., Stewart, K., Wang, X., Yang, F. 2011. Response to comment on climate change and mercury accumulation in Canadian high and subarctic lakes. Environ Sci Technol 45: 6705-06.5Deison, R., Smol, J.P., Kokelj, S.V., Pisaric, M.F.J., Kimpe, L.E., Poulain, A.J., Sanei, H., Theinpoint, J.R., Blais, J.M. 2012. Spatial and

  15. Collembola at three alpine subarctic sites resistant to twenty years of experimental warming

    Czech Academy of Sciences Publication Activity Database

    Alatalo, J.M.; Jägerbrand, A.K.; Čuchta, Peter

    2015-01-01

    Roč. 5, December (2015), s. 18161 ISSN 2045-2322 Institutional support: RVO:60077344 Keywords : Collembola * alpine subarctic sites * experimental warming Subject RIV: EH - Ecology, Behaviour Impact factor: 5.228, year: 2015

  16. Enzymology under global change: organic nitrogen turnover in alpine and sub-Arctic soils

    NARCIS (Netherlands)

    Weedon, J.T.; Aerts, R.; Kowalchuk, G.A.; van Bodegom, P.M.

    2011-01-01

    Understanding global change impacts on the globally important carbon storage in alpine, Arctic and sub-Arctic soils requires knowledge of the mechanisms underlying the balance between plant primary productivity and decomposition. Given that nitrogen availability limits both processes, understanding

  17. Enzymology under global change: organic nitrogen turnover in alpine and sub-Arctic soils.

    NARCIS (Netherlands)

    Weedon, J.T.; Aerts, R.; Kowalchuk, G.A.; van Bodegom, P.M.

    2011-01-01

    Understanding global change impacts on the globally important carbon storage in alpine, Arctic and sub-Arctic soils requires knowledge of the mechanisms underlying the balance between plant primary productivity and decomposition. Given that nitrogen availability limits both processes, understanding

  18. Optimal sleep duration in the subarctic with respect to obesity risk is 8-9 hours

    National Research Council Canada - National Science Library

    Johnsen, May Trude; Wynn, Rolf; Bratlid, Trond

    2013-01-01

    ...) and abdominal obesity. The optimal sleep duration regarding BMI has previously been found to be 7-8 hours, but these studies have not been carried out in the subarctic or have lacked some central variables...

  19. Energy Design Guidelines for High Performance Schools: Arctic and Subarctic Climates

    Energy Technology Data Exchange (ETDEWEB)

    2004-11-01

    The Energy Design Guidelines for High Performance Schools--Arctic and Subarctic Climates provides school boards, administrators, and design staff with guidance to help them make informed decisions about energy and environmental issues important to school systems and communities. These design guidelines outline high performance principles for the new or retrofit design of your K-12 school in arctic and subarctic climates. By incorporating energy improvements into their construction or renovation plans, schools can significantly reduce energy consumption and costs.

  20. Probable limits of sea ice extent in the northwestern Subarctic Pacific during the last glacial maximum

    Science.gov (United States)

    Matul, A. G.

    2017-09-01

    The article summarizes and analyzes published data on the distribution of sea-ice and open-ocean diatoms in 42 cores of bottom sediments from the northwestern part of the Subarctic Pacific that accumulated during the last glacial maximum (LGM). Based on micropaleontological records, the extent of winter sea ice during the LGM could be limited to the Okhotsk and Bering seas. During the warm season, the surface water masses from the open Subarctic Pacific spread widely in the marginal seas.

  1. Optimal Sleep Duration in the Subarctic with Respect to Obesity Risk Is 8?9 Hours

    OpenAIRE

    May Trude Johnsen; Rolf Wynn; Trond Bratlid

    2013-01-01

    INTRODUCTION: Sleep duration, chronotype and social jetlag have been associated with body mass index (BMI) and abdominal obesity. The optimal sleep duration regarding BMI has previously been found to be 7-8 hours, but these studies have not been carried out in the subarctic or have lacked some central variables. The aims of our study were to examine the associations between sleep variables and body composition for people living in the subarctic, taking a range of variables into consideration,...

  2. Pacific Northwest Laboratory annual report for 1980 to the DOE Assistant Secretary for Environment. Part 5. Environmental assessment, control, health and safety

    Energy Technology Data Exchange (ETDEWEB)

    Baalman, R.W.; Hays, I.D. (eds.)

    1981-02-01

    Pacific Northwest Laboratory's (PNL) 1980 annual report to the DOE Assistant Secretary for Environment describes research in environment, health, and safety conducted during fiscal year 1980. Part 5 includes technology assessments for natural gas, enhanced oil recovery, oil shale, uranium mining, magnetic fusion energy, solar energy, uranium enrichment and industrial energy utilization; regional analysis studies of environmental transport and community impacts; environmental and safety engineering for LNG, oil spills, LPG, shale oil waste waters, geothermal liquid waste disposal, compressed air energy storage, and nuclear/fusion fuel cycles; operational and environmental safety studies of decommissioning, environmental monitoring, personnel dosimetry, and analysis of criticality safety; health physics studies; and epidemiological studies. Also included are an author index, organization of PNL charts and distribution lists of the annual report, along with lists of presentations and publications. (DLS)

  3. Phytoremediation of subarctic soil contaminated with diesel fuel

    Energy Technology Data Exchange (ETDEWEB)

    Palmroth, M.R.T.; Puhakka, J.A. [Tampere University of Technology (Finland). Institute of Environmental Engineering and Biotechnology; Pichtel, J. [Ball State University, Muncie, IN (United States). Natural Resources and Environmental Management

    2002-09-01

    The effects of several plant species, native to northern latitudes, and different soil amendments, on diesel fuel removal from soil were studied. Plant treatments included Scots Pine (Pinus sylvestris), Poplar (Populus deltoides x Wettsteinii), a grass mixture (Red fescue, Festuca rubra; Smooth meadowgrass, Poa pratensis and Perennial ryegrass, Lolium perenne) and a legume mixture (White clover, Trifolium repens and Pea, Pisum sativum). Soil amendments included NPK fertiliser, a compost extract and a microbial enrichment culture. Diesel fuel disappeared more rapidly in the legume treatment than in other plant treatments. The presence of poplar and pine enhanced removal of diesel fuel, but removal under grass was similar to that with no vegetation. Soil amendments did not enhance diesel fuel removal significantly. Grass roots accumulated diesel-range compounds. This study showed that utilisation of selected plants accelerates removal of diesel fuel in soil and may serve as a viable, low-cost remedial technology for diesel-contaminated soils in subarctic regions. (author)

  4. Summer (subarctic) versus winter (subtropic) production affects spinach (Spinacia oleracea L.) leaf bionutrients: vitamins (C, E, Folate, K1, provitamin A), lutein, phenolics, and antioxidants.

    Science.gov (United States)

    Lester, Gene E; Makus, Donald J; Hodges, D Mark; Jifon, John L

    2013-07-24

    Comparison of spinach (Spinacia oleracea L.) cultivars Lazio and Samish grown during the summer solstice in the subarctic versus the winter solstice in the subtropics provided insight into interactions between production environment (light intensity), cultivar, and leaf age/maturity/position affecting bionutrient concentrations of vitamins (C, E, folate, K1, provitamin A), lutein, phenolics, and antioxidants. Growing spinach during the winter solstice in the subtropics resulted in increased leaf dry matter %, oxidized (dehydro) ascorbic acid (AsA), α- and γ-tocopherol, and total phenols but lower reduced (free) AsA, α-carotene, folate, and antioxidant capacity compared to summer solstice-grown spinach in the subarctic. Both cultivars had similar bionutrients, except for higher dehydroAsA, and lower α- and γ-tocopherol in 'Samish' compared to 'Lazio'. For most bionutrients measured, there was a linear, and sometimes quadratic, increase in concentrations from bottom to top canopy leaves. However, total phenolics and antioxidant capacity increased basipetally. The current study has thus demonstrated that dehydroAsA, α-tocopherol, and γ-tocopherol were substantially lower in subarctic compared to subtropical-grown spinach, whereas the opposite relationship was found for antioxidant capacity, α-carotene, and folates (vitamin B9). The observations are consistent with previously reported isolated effects of growth environment on bionutrient status of crops. The current results clearly highlight the effect of production environment (predominantly radiation capture), interacting with genetics and plant phenology to alter the bionutrient status of crops. While reflecting the effects of changing growing conditions, these results also indicate potential alterations in the nutritive value of foods with anticipated shifts in global climatic conditions.

  5. Ecosystem change and stability over multiple decades in the Swedish subarctic: complex processes and multiple drivers.

    Science.gov (United States)

    Callaghan, Terry V; Jonasson, Christer; Thierfelder, Tomas; Yang, Zhenlin; Hedenås, Henrik; Johansson, Margareta; Molau, Ulf; Van Bogaert, Rik; Michelsen, Anders; Olofsson, Johan; Gwynn-Jones, Dylan; Bokhorst, Stef; Phoenix, Gareth; Bjerke, Jarle W; Tømmervik, Hans; Christensen, Torben R; Hanna, Edward; Koller, Eva K; Sloan, Victoria L

    2013-08-19

    The subarctic environment of northernmost Sweden has changed over the past century, particularly elements of climate and cryosphere. This paper presents a unique geo-referenced record of environmental and ecosystem observations from the area since 1913. Abiotic changes have been substantial. Vegetation changes include not only increases in growth and range extension but also counterintuitive decreases, and stability: all three possible responses. Changes in species composition within the major plant communities have ranged between almost no changes to almost a 50 per cent increase in the number of species. Changes in plant species abundance also vary with particularly large increases in trees and shrubs (up to 600%). There has been an increase in abundance of aspen and large changes in other plant communities responding to wetland area increases resulting from permafrost thaw. Populations of herbivores have responded to varying management practices and climate regimes, particularly changing snow conditions. While it is difficult to generalize and scale-up the site-specific changes in ecosystems, this very site-specificity, combined with projections of change, is of immediate relevance to local stakeholders who need to adapt to new opportunities and to respond to challenges. Furthermore, the relatively small area and its unique datasets are a microcosm of the complexity of Arctic landscapes in transition that remains to be documented.

  6. High variation subarctic topsoil pollutant concentration prediction using neural network residual kriging

    Science.gov (United States)

    Sergeev, A. P.; Tarasov, D. A.; Buevich, A. G.; Subbotina, I. E.; Shichkin, A. V.; Sergeeva, M. V.; Lvova, O. A.

    2017-06-01

    The work deals with the application of neural networks residual kriging (NNRK) to the spatial prediction of the abnormally distributed soil pollutant (Cr). It is known that combination of geostatistical interpolation approaches (kriging) and neural networks leads to significantly better prediction accuracy and productivity. Generalized regression neural networks and multilayer perceptrons are classes of neural networks widely used for the continuous function mapping. Each network has its own pros and cons; however both demonstrated fast training and good mapping possibilities. In the work, we examined and compared two combined techniques: generalized regression neural network residual kriging (GRNNRK) and multilayer perceptron residual kriging (MLPRK). The case study is based on the real data sets on surface contamination by chromium at a particular location of the subarctic Novy Urengoy, Russia, obtained during the previously conducted screening. The proposed models have been built, implemented and validated using ArcGIS and MATLAB environments. The networks structures have been chosen during a computer simulation based on the minimization of the RMSE. MLRPK showed the best predictive accuracy comparing to the geostatistical approach (kriging) and even to GRNNRK.

  7. Effects of freeze-thaw cycles on microarthropods and nutrient availability in a sub-arctic soil

    DEFF Research Database (Denmark)

    Sjursen, Heidi; Michelsen, Anders; Holmstrup, Martin

    2005-01-01

    content were examined. There was no conclusive evidence that recurring freeze-thaw events had a negative effect on the investigated soil faunal groups, and the treatment even seemed to stimulate the abundance of Acaridida. Respiration of soil subjected to 16 freeze-thaw cycles was low when kept at -2 °C......It is predicted that Arctic regions may experience an increase in mean temperature in the future. This will affect the frequency of severe climatic events such as summer droughts and freeze-thaw cycles. In order to understand the impact of recurring freezing and thawing on soil organisms...... and their environment, intact plant-soil samples from the sub-Arctic were subjected to a series of such events. Springtail and mite species composition and abundance were monitored at intervals throughout the experiment. Furthermore, nutrient content and mobilisation in the soil and soil microbial biomass and nutrient...

  8. Effects of a warmer climate on seed germination in the subarctic

    Science.gov (United States)

    Milbau, Ann; Graae, Bente Jessen; Shevtsova, Anna; Nijs, Ivan

    2009-01-01

    Background and Aims In a future warmer subarctic climate, the soil temperatures experienced by dispersed seeds are likely to increase during summer but may decrease during winter due to expected changes in snow depth, duration and quality. Because little is known about the dormancy-breaking and germination requirements of subarctic species, how warming may influence the timing and level of germination in these species was examined. Methods Under controlled conditions, how colder winter and warmer summer soil temperatures influenced germination was tested in 23 subarctic species. The cold stratification and warm incubation temperatures were derived from real soil temperature measurements in subarctic tundra and the temperatures were gradually changed over time to simulate different months of the year. Key Results Moderate summer warming (+2·5 °C) substantially accelerated germination in all but four species but did not affect germination percentages. Optimum germination temperatures (20/10°C) further decreased germination time and increased germination percentages in three species. Colder winter soil temperatures delayed the germination in ten species and decreased the germination percentage in four species, whereas the opposite was found in Silene acaulis. In most species, the combined effect of a reduced snow cover and summer warming resulted in earlier germination and thus a longer first growing season, which improves the chance of seedling survival. In particular the recruitment of (dwarf) shrubs (Vaccinium myrtillus, V. vitis-idaea, Betula nana), trees (Alnus incana, Betula pubescens) and grasses (Calamagrostis lapponica, C. purpurea) is likely to benefit from a warmer subarctic climate. Conclusions Seedling establishment is expected to improve in a future warmer subarctic climate, mainly by considerably earlier germination. The magnitudes of the responses are species-specific, which should be taken into account when modelling population growth and migration

  9. Within-and among-year germination in Sonoran Desert winter annuals: bet hedging and predictive germination in a variable environment.

    Science.gov (United States)

    Gremer, Jennifer R; Kimball, Sarah; Venable, D Lawrence

    2016-10-01

    In variable environments, organisms must have strategies to ensure fitness as conditions change. For plants, germination can time emergence with favourable conditions for later growth and reproduction (predictive germination), spread the risk of unfavourable conditions (bet hedging) or both (integrated strategies). Here we explored the adaptive value of within- and among-year germination timing for 12 species of Sonoran Desert winter annual plants. We parameterised models with long-term demographic data to predict optimal germination fractions and compared them to observed germination. At both temporal scales we found that bet hedging is beneficial and that predicted optimal strategies corresponded well with observed germination. We also found substantial fitness benefits to varying germination timing, suggesting some degree of predictive germination in nature. However, predictive germination was imperfect, calling for some degree of bet hedging. Together, our results suggest that desert winter annuals have integrated strategies combining both predictive plasticity and bet hedging. © 2016 John Wiley & Sons Ltd/CNRS.

  10. Modeled and measured linkages between glaciers, permafrost and hydrology in a subarctic watershed, Interior Alaska

    Science.gov (United States)

    Gaedeke, A.; Liljedahl, A. K.; O'Neel, S.; Douglas, T. A.; Gatesman, T.; Daanen, R. P.; Zhang, J.; Campbell, S. W.

    2016-12-01

    Hydrological processes in subarctic, mountainous, glacierized watersheds are highly variable (seasonally and spatially) and are particularly vulnerable to climate change. Here, we combine field measurements and hydrological modeling to address the effects of altered glacier melt on lowland runoff, regional groundwater recharge/storage and permafrost distribution. Jarvis Creek watershed (630 km2), a headwater basin of the Tanana River (12,000 km2), in semi-arid Interior Alaska serves as our study area. The process-based, spatially distributed hydrological model WaSiM was utilized to simulate all aspects of the water cycle, including glacier melt, dynamic glacier coverage, seasonal soil freeze and thaw and permafrost. Downscaled regional climate scenarios force WaSiM for long-term climate change impact assessment. Field measurements (differential runoff, glacier mass balance, end-of-winter snow depths, soil temperature, and meteorology) are used to parameterize, calibrate and validate WaSiM. Our field measurements and modeling results indicate that Jarvis Creek, which is fed by on average 1/3 glacier runoff during summer, loses considerable amount of runoff to the regional aquifer. The aquifer, in turn, feeds the larger scale river system (Tanana River) throughout the year, which is especially prominent during winter when all overland runoff ceases and surface waters are covered with ice. Measured annual runoff increased from the nearby Gulkana Glacier during the last 50 years, which is consistent with an 11% decrease in glacier coverage (1950-2010) within the Tanana River basin. Glacier runoff is likely to continue to increase until glaciers recede to higher and cooler elevation. The changes in glacier runoff do not only affect the headwater streams (Jarvis Creek), but also the larger scale hydrological regime such as aquifer storage and release, long-term trends in winter baseflow of Tanana River and permafrost distribution.

  11. Environment

    DEFF Research Database (Denmark)

    Valentini, Chiara

    2017-01-01

    The term environment refers to the internal and external context in which organizations operate. For some scholars, environment is defined as an arrangement of political, economic, social and cultural factors existing in a given context that have an impact on organizational processes and structures....... For others, environment is a generic term describing a large variety of stakeholders and how these interact and act upon organizations. Organizations and their environment are mutually interdependent and organizational communications are highly affected by the environment. This entry examines the origin...... and development of organization-environment interdependence, the nature of the concept of environment and its relevance for communication scholarships and activities....

  12. pH gradients in the diffusive boundary layer of subarctic macrophytes

    KAUST Repository

    Hendriks, Iris E.

    2017-06-20

    Highly productive macrophytes produce diurnal and seasonal cycles in CO concentrations modulated by metabolic activity, which cause discrepancies between pH in the bulk water and near seaweed blades, especially when entering the diffusion boundary layer (DBL). Calcifying epiphytic organisms living in this environment are therefore exposed to a different pH environment than that of the water column. To evaluate the actual pH environment on blade surfaces, we measured the thickness of the DBL and pH gradients within it for six subarctic macrophytes: Fucus vesiculosus, Ascophyllum nodosum, Ulva lactuca, Zostera marina, Saccharina longicruris, and Agarum clathratum. We measured pH under laboratory conditions at ambient temperatures (2–3 °C) and slow, stable flow over the blade surface at five light intensities (dark, 30, 50, 100 and 200 µmol photons m s). Boundary layer thickness ranged between 511 and 1632 µm, while the maximum difference in pH (∆pH) between the blade surface and the water column ranged between 0.4 ± 0.14 (average ± SE; Zostera) and 1.2 ± 0.13 (average ± SE; Ulva) pH units. These differences in pH are larger than predictions for pH changes in the bulk water by the end of the century. A simple quadratic model best described the relationship between light intensity and maximum ∆pH, pointing at relatively low optimum PAR of between 28 and 139 µmol photons m s to reach maximum ∆pH. Elevated pH at the blade surface may provide chemical “refugia” for calcifying epiphytic organisms, especially during summer at higher latitudes where photoperiods are long.

  13. Prokaryotic Community Composition in Arctic Kongsfjorden and Sub-Arctic Northern Bering Sea Sediments As Revealed by 454 Pyrosequencing

    Directory of Open Access Journals (Sweden)

    Yin-Xin Zeng

    2017-12-01

    Full Text Available Fjords and continental shelves represent distinct marine ecosystems in the pan-arctic region. Kongsfjorden is a glacial fjord that is located on the west coast of Svalbard, and is influenced by both Atlantic and Arctic water masses. The Bering Sea consists of a huge continental shelf in the northeast and a deep ocean basin in the southwest, and is influenced by Pacific water. Microbial community compositions of Arctic sediment samples BJ4 from outer basin and BJ36 from inner basin of Kongsfjorden and sub-Arctic samples NEC5 from shallow shelf and DBS1 from deep basin region of the northern Bering Sea were investigated using 454 pyrosequencing of archaeal and bacterial 16S rRNA genes. Most archaeal sequences in the sediments were related to Thaumarchaeota, though Euryarchaeota were more abundant in the Arctic glacier-influencing inner basin sediment BJ36. Thaumarchaeota Group C3 was the dominant archaeal population in all samples. Proteobacteria and Bacteroidetes dominated the sediment bacterial communities. Acidobacteria and Actinobacteria were also dominant in the northern Bering Sea samples. Alphaproteobacteria and Epsilonproteobacteria were the two main classes in Kongsfjorden sediment bacterial communities while Deltaproteobacteria and Gammaproteobacteria were dominant in the northern Bering Sea sediments. Differences in the presence and abundance of other dominant archaeal and bacterial populations were observed among sediment samples. In contrast to archaeal community differences that the Arctic BJ36 archaeal community was distinct from the sub-Arctic sediments and the Arctic outer basin sediment BJ4, cluster analysis based on bacterial OTU (operational taxonomic unit distributions indicated that the Arctic and sub-Arctic bacterial communities segregated from one another. These results suggest that the sediment archaeal and bacterial community compositions can be driven by different environmental factors. Differences in the presence and

  14. Pacific Northwest Laboratory annual report for 1979 to the DOE Assistant Secretary for Environment. Part 5. Environmental assessment, control, health, and safety

    Energy Technology Data Exchange (ETDEWEB)

    Baalman, R.W.; Dotson, C.W. (eds.)

    1980-02-01

    Part 5 of the 1979 Annual Report to the Department of Energy Assistant Secretary for the Environment presents Pacific Northwest Laboratory's progress on work performed for the Office of Technology Impacts, the Office of Environmental Compliance and Overview, and the Office of Health and Environmental Research. The report is in four sections, corresponding to the program elements: technology impacts, environmental control engineering, operational and environmental compliance, and human health studies. In each section, articles describe progress made during FY 1979 on individual projects.

  15. Diazotrophy in alluvial meadows of subarctic river systems.

    Science.gov (United States)

    DeLuca, Thomas H; Zackrisson, Olle; Bergman, Ingela; Díez, Beatriz; Bergman, Birgitta

    2013-01-01

    There is currently limited understanding of the contribution of biological N2 fixation (diazotrophy) to the N budget of large river systems. This natural source of N in boreal river systems may partially explain the sustained productivity of river floodplains in Northern Europe where winter fodder was harvested for centuries without fertilizer amendments. In much of the world, anthropogenic pollution and river regulation have nearly eliminated opportunities to study natural processes that shaped early nutrient dynamics of large river systems; however, pristine conditions in northern Fennoscandia allow for the retrospective evaluation of key biochemical processes of historical significance. We investigated biological N2 fixation (diazotrophy) as a potential source of nitrogen fertility at 71 independent floodplain sites along 10 rivers and conducted seasonal and intensive analyses at a subset of these sites. Biological N2 fixation occurred in all floodplains, averaged 24.5 kg N ha(-1) yr(-1) and was down regulated from over 60 kg N ha(-1) yr(-1) to 0 kg N ha(-1) yr(-1) by river N pollution. A diversity of N2-fixing cyanobacteria was found to colonize surface detritus in the floodplains. The data provide evidence for N2 fixation to be a fundamental source of new N that may have sustained fertility at alluvial sites along subarctic rivers. Such data may have implications for the interpretation of ancient agricultural development and the design of contemporary low-input agroecosystems.

  16. Diazotrophy in alluvial meadows of subarctic river systems.

    Directory of Open Access Journals (Sweden)

    Thomas H DeLuca

    Full Text Available There is currently limited understanding of the contribution of biological N2 fixation (diazotrophy to the N budget of large river systems. This natural source of N in boreal river systems may partially explain the sustained productivity of river floodplains in Northern Europe where winter fodder was harvested for centuries without fertilizer amendments. In much of the world, anthropogenic pollution and river regulation have nearly eliminated opportunities to study natural processes that shaped early nutrient dynamics of large river systems; however, pristine conditions in northern Fennoscandia allow for the retrospective evaluation of key biochemical processes of historical significance. We investigated biological N2 fixation (diazotrophy as a potential source of nitrogen fertility at 71 independent floodplain sites along 10 rivers and conducted seasonal and intensive analyses at a subset of these sites. Biological N2 fixation occurred in all floodplains, averaged 24.5 kg N ha(-1 yr(-1 and was down regulated from over 60 kg N ha(-1 yr(-1 to 0 kg N ha(-1 yr(-1 by river N pollution. A diversity of N2-fixing cyanobacteria was found to colonize surface detritus in the floodplains. The data provide evidence for N2 fixation to be a fundamental source of new N that may have sustained fertility at alluvial sites along subarctic rivers. Such data may have implications for the interpretation of ancient agricultural development and the design of contemporary low-input agroecosystems.

  17. Impact of special early harvest seasons on subarctic-nesting and temperate-nesting Canada geese

    Science.gov (United States)

    Sheaffer, S.E.; Kendall, W.L.; Bowers, E. Frank

    2005-01-01

    Dramatic changes in wintering distributions of Canada geese (Branta canadensis) have occurred over the past 50 years in eastern North America. Declines in numbers of subarctic-nesting geese wintering in southern states, and increases in numbers wintering in northern regions, have resulted in a northern shift in winter distributions. In contrast, numbers of temperate-nesting geese have increased throughout eastern North America. Management efforts to control overabundant temperate-nesting flocks have included the establishment of special early harvest seasons in September. However, the effect of early seasons on survival and harvest of subarctic-nesting populations has not been documented. Understanding the timing of migration movements and the fidelity of subarctic-nesting flocks to terminal winter refuges in the Southeast also is necessary to design early harvest seasons that target temperate-nesting flocks and protect subarctic-nesting populations. We used recoveries of marked geese to estimate survival and harvest rates before and after implementation of early harvest seasons within the Mississippi Flyway during 1976-1999. In addition, we used observations of neck-banded geese from the Southern James Bay Population (SJBP) to evaluate the hypothesis that subarctic-nesting geese arriving prior to mid-December on several key terminal winter refuges in the Southeast (early arriving migrants) were more likely to return to those refuges in subsequent years than were migrants, arriving after mid-December (late arriving migrants). September seasons during 1987-1994 were a minor source of mortality for subarctic-nesting populations and accounted for migrants had higher survival and higher return probabilities than did late arriving migrants or geese that failed to return, numbers of geese wintering on southeastern refuges likely declined because < 60% of the surviving geese affiliated with the refuges would return in a given year and because of lower survival for geese

  18. Constraints to obtaining consistent annual yields in perennials. II: Environment and fruit load affect induction of flowering.

    Science.gov (United States)

    Samach, Alon; Smith, Harley M

    2013-06-01

    In many commercial fruit crop species, high fruit load inhibits vegetative growth and floral induction. As a result, trees that had a high fruit load will bear few flowers and fruit the following year, along with abundant vegetative growth. We previously discussed how high fruit load interferes with concurrent shoot growth. Here we focus on how high fruit load impacts the process of flowering. Ascertaining the precise time at which specific buds begin the floral transition in each species is challenging. The use of indirect approaches to determine time of floral induction or evocation may lead to questionable conclusions. Annual and perennial plants appear to use conserved proteins for flowering induction and initiation. The accumulation or reduction of transcripts encoding proteins similar to Arabidopsis (annual) FLOWERING LOCUS T (FT) and TERMINAL FLOWER1 (TFL1), respectively, correlates well with flower induction in several diverse species. The recent use of such markers provides a means to formulate an accurate timeframe for floral induction in different species and holds promise in providing new insight into this important developmental event. A role for hormones in modulating the inhibitory effect of fruit load on floral induction is also discussed. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  19. Hydrological role of large icings within glacierized Sub-Arctic watershed: case study in Upper Duke River valley, Yukon, Canada.

    Science.gov (United States)

    Chesnokova, Anna; Baraer, Michel

    2017-04-01

    Sub-Arctic glacierized catchments are complex hydrological systems of paramount importance for water resources management as well as for various ecosystem services. Such systems host many climate-sensitive water sources. Among those, icing is an important component as they provide substantial amount of water during the melt season. Moreover, collecting water of different origins during their formation, icings can be seen as an indicator for different water sources and water pathways that remain active during the freezing period. The present study focuses on genesis and dynamics of large icings within both proglacial field and neighboring alpine meadow in Upper Duke River valley, Yukon, in order to i) provide new insights on water sources and pathways within Sub-Arctic glacierized watersheds, and ii) to quantify contribution of icings to the total runoff of those hydrological systems. A multi-approach technique was applied to cope with the high hydrological complexity met in Sub-Arctic mountainous environments. Time series of positions of large river icings within the study area were obtained using Landsat images for the period 1980-2016. Four time-lapse cameras (TLC) were installed in the watershed targeting two proglacial fields and two alpine meadows in order to monitor icing dynamics all year long. Meteorological data was measured by an Automatic Weather Station in the main valley. In addition air temperature and relative humidity were measured at the location of each TLC. Finally, four icings along the Duke River valley, as well as 2 icings in its main tributary were sampled for stable water isotopes, solutes concentrations and total organic carbon. In addition, samples of freezing exclusion precipitates from icing surfaces were taken. Remote sensing data shows the persistence of large icing complexes in the area during last 30 years: icing within proglacial field appear with almost constant position relative to main glacier tongue on the 30 years long period

  20. Krill community composition and grazing biology in a sub-Arctic Greenlandic fjord

    DEFF Research Database (Denmark)

    Teglhus, Frederik Wolff; Agersted, Mette Dalgaard; Arendt, Kristine Engel

    of organic material, i.e. the biological pump. Our aim is to improve the understanding and knowledge about the role of krill in a sub-Arctic fjord. During multiple cruises in the Godthåbsfjord, Southwest Greenland, krill abundance, distribution and grazing biology have been investigated trough field....... The present novel knowledge about krill abundance and grazing biology will provide the basis for a discussion of the role of krill in the pelagic food web of the sub-Arctic Godthåbsfjord...

  1. Active Layer Monitoring, Arctic and Subarctic Canada, Version 6

    Data.gov (United States)

    National Aeronautics and Space Administration — This project involves measuring regional and site variability in maximum annual active layer development and vertical surface movement over permafrost, and...

  2. Performance of insulated pipelines in sub-Arctic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, M. [Garneau Inc., Calgary, AB (Canada); D' Agostino, C. [Nova Chemicals, Calgary, AB (Canada)

    2000-07-01

    A systematic investigation was conducted to determine the main reasons why the insulating value of a pipeline overcoated with extruded polyethylene might fail, particularly in sub-Arctic regions. An insulated pipeline should have excellent insulation values as well as perfect anti-corrosion barrier coatings and an excellent adhesion between the anti-corrosion coating and the polyurethane foam. An insulated pipeline should also be bendable at the ambient construction temperature without damage to the foam or other components of the system. It should also be protected by an outer coating to withstand high mechanical impact. Three types of anti-corrosion barrier coatings are fusion bond epoxy, polyethylene tape, and three layer polyolefin. Polyurethane foam is one of the best heat insulating materials available with an average thermal conductivity of 0.22 W/mK, but it possesses very little mechanical strength. Therefore, it must be overcoated by an external jacket of either polyethylene pipeline tape, extruded polyethylene or spray applied elastomeric polyurethane coatings. An extensive laboratory testing program was initiated to respond to field failures of insulated pipe and low temperatures. The objective was to verify the mechanical properties of insulated pipe at different temperatures. It was shown that at low temperatures, high density polyethylene (HDPE) had significantly reduced elongation properties and its tensile strength increased. It was also determined that double and triple outer jackets provided better impact resistance at low temperature than the single jacket of equivalent thickness. Comparison tests were also conducted with low density polyethylenes. Linear low density polyethylene (LLDPE) was found to be particularly resistant to low temperature damage. In addition, a black jacket proved to be much warmer than a white jacket. On sunny days, the temperature difference could be as high as 15 degrees C. 5 tabs.

  3. Temporal changes in soil bacterial diversity and humic substances degradation in subarctic tundra soil.

    Science.gov (United States)

    Park, Ha Ju; Chae, Namyi; Sul, Woo Jun; Lee, Bang Yong; Lee, Yoo Kyung; Kim, Dockyu

    2015-04-01

    Humic substances (HS), primarily humic acids (HA) and fulvic acids (FA), are the largest constituent of soil organic matter. In microcosm systems with subarctic HS-rich tundra soil (site AK 1-75; approximately 5.6 °C during the thawing period) from Council, Alaska, the HA content significantly decreased to 48% after a 99-day incubation at 5 °C as part of a biologically mediated process. Accordingly, levels of FA, a putative byproduct of HA degradation, consistently increased to 172% during an identical incubation process. Culture-independent microbial community analysis showed that during the microcosm experiments, the relative abundance of phyla Proteobacteria (bacteria) and Euryarchaeota (archaea) largely increased, indicating their involvement in HS degradation. When the indigenous bacteria in AK 1-75 were enriched in an artificial mineral medium spiked with HA, the changes in relative abundance were most conspicuous in Proteobacteria (from 60.2 to 79.0%), specifically Betaproteobacteria-related bacteria. One hundred twenty-two HA-degrading bacterial strains, primarily from the genera Paenibacillus (phylum Firmicutes) and Pseudomonas (class Gammaproteobacteria), were cultivated from AK 1-75 and nearby sites. Through culture-dependent analysis with these bacterial isolates, we observed increasing HS-degradation rates in parallel with rising temperatures in a range of 0 °C to 20 °C, with the most notable increase occurring at 8 °C compared to 6 °C. Our results indicate that, although microbial-mediated HS degradation occurs at temperature as low as 5 °C in tundra ecosystems, increasing soil temperature caused by global climate change could enhance HS degradation rates. Extending the thawing period could also increase degradation activity, thereby directly affecting nearby microbial communities and rhizosphere environments.

  4. FZR annual report 2003: Research for men and environment; FZR-Jahresbericht 2003: Forschung fuer Mensch und Umwelt

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-03-01

    The following topics are dealt with: A multi-purpose experimental facility for the model development of two-phase flows, the first nuclear-physics experiments with bremsstrahlung at the ELBE accelerator, the molecular mechanisms of vision and general principles of the cellular signal processing, colloids in environment, protein oxidation and sickness, nondestructive study on glass pretiosa using proton beams. (HSI)

  5. Fluxes of Methane and Carbon Dioxide from a Subarctic Lake

    DEFF Research Database (Denmark)

    Jammet, Mathilde Manon

    . This prevents in particular accurate estimates of the total emission of CH4 and CO2 from seasonally ice-covered lakes. This thesis aims to address these spatial and temporal issues to improve quantification and understanding of surface-atmosphere exchange of CH4 and CO2 by using the eddy covariance method...... of an ice lid in winter over the lake surface likely prevents gas exchange with the atmosphere and allows buildup of CH4 in the anoxic bottom. Although the contribution of winter and spring to annual emissions of CH4 and CO2 was significant for both ecosystems, spring season emissions were disproportionally...... important for the lake annual emissions compared to the length of the period, as it turned the lake from a small summer CO2 sink into an annual source. Annual inter-annual variability was notable in the magnitude of the CH4 spring release and needs further investigation. The high temporal resolution...

  6. Replacement cost valuation of Northern Pintail (Anas acuta) subsistence harvest in Arctic and sub-Arctic North America

    Science.gov (United States)

    Goldstein, Joshua H.; Thogmartin, Wayne E.; Bagstad, Kenneth J.; Dubovsky, James A.; Mattsson, Brady J.; Semmens, Darius J.; López-Hoffman, Laura; Diffendorfer, James E.

    2014-01-01

    Migratory species provide economically beneficial ecosystem services to people throughout their range, yet often, information is lacking about the magnitude and spatial distribution of these benefits at regional scales. We conducted a case study for Northern Pintails (hereafter pintail) in which we quantified regional and sub-regional economic values of subsistence harvest to indigenous communities in Arctic and sub-Arctic North America. As a first step, we used the replacement cost method to quantify the cost of replacing pintail subsistence harvest with the most similar commercially available protein (chicken). For an estimated annual subsistence harvest of ˜15,000 pintail, our mean estimate of the total replacement cost was ˜$63,000 yr−1 ($2010 USD), with sub-regional values ranging from \\$263 yr−1 to \\$21,930 yr−1. Our results provide an order-of-magnitude, conservative estimate of one component of the regional ecosystem-service values of pintails, providing perspective on how spatially explicit values can inform migratory species conservation.

  7. Hazardous materials in aquatic environments of the Mississippi River Basin. Annual technical report, December 30, 1992--December 29, 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-31

    Tulane and Xavier Universities have singled out the environment as a major strategic focus for research and training for now and by the year 2000. In December, 1992, the Tulane/Xavier CBR was awarded a five year grant to study pollution in the Mississippi River system. The ``Hazardous Materials in Aquatic Environments of the Mississippi River Basin`` project is a broad research and education program aimed at elucidating the nature and magnitude of toxic materials that contaminate aquatic environments of the Mississippi River Basin. Studies include defining the complex interactions that occur during the transport of contaminants, the actual and potential impact on ecological systems and health, and the mechanisms through which these impacts might be remediated. The Mississippi River Basin represents a model system for analyzing and solving contamination problems that are found in aquatic systems world-wide. These research and education projects are particularly relevant to the US Department of Energy`s programs aimed at addressing aquatic pollution problems associated with DOE National Laboratories. First year funding supported seven collaborative cluster projects and twelve initiation projects. This report summarizes research results for period December 1992--December 1993.

  8. Hazardous materials in aquatic environments of the Mississippi River Basin. Annual technical report, 30 December 1992--29 December 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-31

    Tulane and Xavier Universities have singled out the environment as a major strategic focus for research and training for now and beyond the year 2000. In 1989, the Tulane/Xavier Center for Bioenvironmental Research (CBR) was established as the umbrella organization which coordinates environmental research at both universities. In December, 1992, the Tulane/Xavier DBR was awarded a five year grant to study pollution in the Mississippi River system. The ``Hazardous Materials in Aquatic Environments of the Mississippi River Basin`` project is a broad research and education program aimed at elucidating the nature and magnitude of toxic materials that contaminate aquatic environments of the Mississippi River Basin. Studies include defining the complex interactions that occur during the transport of contaminants, the actual and potential impact on ecological systems and health, and the mechanisms through which these impacts might be remediated. The Mississippi River Basin represents a model system for analyzing and solving contamination problems that are found in aquatic systems world-wide. Individual papers have been processed separately for inclusion in the appropriate data bases.

  9. Molecular analyses reveal high species diversity of trematodes in a sub-Arctic lake.

    Science.gov (United States)

    Soldánová, Miroslava; Georgieva, Simona; Roháčová, Jana; Knudsen, Rune; Kuhn, Jesper A; Henriksen, Eirik H; Siwertsson, Anna; Shaw, Jenny C; Kuris, Armand M; Amundsen, Per-Arne; Scholz, Tomáš; Lafferty, Kevin D; Kostadinova, Aneta

    2017-05-01

    To identify trematode diversity and life-cycles in the sub-Arctic Lake Takvatn, Norway, we characterised 120 trematode isolates from mollusc first intermediate hosts, metacercariae from second intermediate host fishes and invertebrates, and adults from fish and invertebrate definitive hosts, using molecular techniques. Phylogenies based on nuclear and/or mtDNA revealed high species richness (24 species or species-level genetic lineages) and uncovered trematode diversity (16 putative new species) from five families typical in lake ecosystems (Allocreadiidae, Diplostomidae, Plagiorchiidae, Schistosomatidae and Strigeidae). Sampling potential invertebrate hosts allowed matching of sequence data for different stages, thus achieving molecular elucidation of trematode life-cycles and exploration of host-parasite interactions. Phylogenetic analyses also helped identify three major mollusc intermediate hosts (Radix balthica, Pisidium casertanum and Sphaerium sp.) in the lake. Our findings increase the known trematode diversity at the sub-Arctic Lake Takvatn, showing that digenean diversity is high in this otherwise depauperate sub-Arctic freshwater ecosystem and indicating that sub-Arctic and Arctic ecosystems may be characterised by unique trematode assemblages. Copyright © 2017 Australian Society for Parasitology. All rights reserved.

  10. Youth Environmental Science Outreach in the Mushkegowuk Territory of Subarctic Ontario, Canada

    Science.gov (United States)

    Karagatzides, Jim D.; Kozlovic, Daniel R.; De Iuliis, Gerry; Liberda, Eric N.; General, Zachariah; Liedtke, Jeff; McCarthy, Daniel D.; Gomez, Natalya; Metatawabin, Daniel; Tsuji, Leonard J. S.

    2011-01-01

    We connected youth of the Mushkegowuk Territory (specifically Fort Albany First Nation) with environmental science and technology mentors in an outreach program contextualized to subarctic Ontario that addressed some of the environmental concerns identified by members of Fort Albany First Nation. Most activities were community-based centering on…

  11. Trophic role and top-down control of a subarctic protozooplankton community

    DEFF Research Database (Denmark)

    Riisgaard, Karen; Swalethorp, Rasmus; Kjellerup, Sanne

    2014-01-01

    Plankton succession was investigated in the subarctic Godthåbsfjord, Western Greenland, from March to August 2010. The trophic role of protozooplankton (ciliates and heterotrophic dinoflagellates) was evaluated with emphasis on their seasonal succession and as prey for the copepod community. The ...

  12. Molecular analyses reveal high species diversity of trematodes in a sub-Arctic lake

    Science.gov (United States)

    Soldánová, Miroslava; Georgieva, Simona; Roháčováa, Jana; Knudsen, Rune; Kuhn, Jesper A.; Henriksen, Eirik H.; Siwertsson, Anna; Shaw, Jenny C.; Kuris, Armand M.; Amundsen, Per-Arne; Scholz, Tomáš; Lafferty, Kevin D.; Kostadinova, Aneta

    2017-01-01

    To identify trematode diversity and life-cycles in the sub-Arctic Lake Takvatn, Norway, we characterised 120 trematode isolates from mollusc first intermediate hosts, metacercariae from second intermediate host fishes and invertebrates, and adults from fish and invertebrate definitive hosts, using molecular techniques. Phylogenies based on nuclear and/or mtDNA revealed high species richness (24 species or species-level genetic lineages), and uncovered trematode diversity (16 putative new species) from five families typical in lake ecosystems (Allocreadiidae, Diplostomidae, Plagiorchiidae, Schistosomatidae and Strigeidae). Sampling potential invertebrate hosts allowed matching of sequence data for different stages, thus achieving molecular elucidation of trematode life-cycles and exploration of host-parasite interactions. Phylogenetic analyses also helped identify three major mollusc intermediate hosts (Radix balthica, Pisidium casertanum and Sphaerium sp.) in the lake. Our findings increase the known trematode diversity at the sub-Arctic Lake Takvatn, showing that digenean diversity is high in this otherwise depauperate sub-Arctic freshwater ecosystem, and indicating that sub-Arctic and Arctic ecosystems may be characterised by unique trematode assemblages.

  13. Role of predation in biological communities in naturally eutrophic sub-Arctic Lake Myvatn, Iceland

    DEFF Research Database (Denmark)

    Canedo-Argueles, Miguel; Sgarzi, Serena; Arranz, Ignasi

    2017-01-01

    . To study this, we conducted a 3-month in situ-controlled experiment in sub-Arctic Lake MA 1/2 vatn, Iceland. We used the planktivorous fish three-spined sticklebacks (Gasterosteus aculeatus) as the main top predator. The cladocerans Eurycercus lamellatus and Acroperus harpae were significantly associated...

  14. Long-term warming and litter addition affects nitrogen fixation in a subarctic heath

    DEFF Research Database (Denmark)

    Sørensen, Pernille Lærkedal; Michelsen, Anders

    2011-01-01

    the effects of anticipated global climate change on N fixation rates in a subarctic moist heath, a field experiment was carried out in Northern Sweden. Warming was induced by plastic tents, and in order to simulate the effects of future increased tree cover, birch litter was added each fall for 9 years before...

  15. Pacific Northwest Laboratory annual report for 1979 to the DOE Assistant Secretary for Environment. Part 2. Ecological sciences

    Energy Technology Data Exchange (ETDEWEB)

    Vaughan, B.E.

    1980-02-01

    Research in Environment, Health, and Safety conducted during fiscal year 1979 is reported. This volume consists of project reports from the Ecological Sciences research department. The reports are grouped under the following subject areas: National Environmental Research Park and land use; Alaskan resource research; shale oil; synfuels; nuclear waste; fission; marine research programs; statistical development of field research; nuclear fusion; pumped storage and hydroelectric development; pathways modelling, assessment and Hanford project support; electric field and microwave research; and energy research for other agencies. (ACR)

  16. Mapping the reduction in gross primary productivity in subarctic birch forests due to insect outbreaks

    Science.gov (United States)

    Olsson, Per-Ola; Heliasz, Michal; Jin, Hongxiao; Eklundh, Lars

    2017-03-01

    It is projected that forest disturbances, such as insect outbreaks, will have an increasingly negative impact on forests with a warmer climate. These disturbance events can have a substantial impact on forests' ability to absorb atmospheric CO2, and may even turn forests from carbon sinks into carbon sources; hence, it is important to develop methods both to monitor forest disturbances and to quantify the impact of these disturbance events on the carbon balance. In this study we present a method to monitor insect-induced defoliation in a subarctic birch forest in northern Sweden, and to quantify the impact of these outbreaks on gross primary productivity (GPP). Since frequent cloud cover in the study area requires data with high temporal resolution and limits the use of finer spatial resolution sensors such as Landsat, defoliation was mapped with remote sensing data from the MODIS sensor with 250 m × 250 m spatial resolution. The impact on GPP was estimated with a light use efficiency (LUE) model that was calibrated with GPP data obtained from eddy covariance (EC) measurements from 5 years with undisturbed birch forest and 1 year with insect-induced defoliation. Two methods were applied to estimate the impact on GPP: (1) applying a GPP reduction factor derived from EC measured GPP to estimate GPP loss, and (2) running a LUE model for both undisturbed and defoliated forest and deriving the differences in modelled GPP. In the study area of 100 km2 the results suggested a substantial setback to the carbon uptake: an average decrease in regional GPP over the three outbreak years (2004, 2012, and 2013) was estimated to 15 ± 5 Gg C yr-1, compared to the mean regional GPP of 40 ± 12 Gg C yr-1 for the 5 years without defoliation, i.e. 38 %. In the most severe outbreak year (2012), 76 % of the birch forests were defoliated, and annual regional GPP was merely 50 % of GPP for years without disturbances. The study has generated valuable data on GPP reduction, and

  17. Carbon dioxide balance of subarctic tundra from plot to regional scales

    Directory of Open Access Journals (Sweden)

    M. E. Marushchak

    2013-01-01

    Full Text Available We report here the carbon dioxide (CO2 budget of a 98.6 km2 subarctic tundra area in northeast European Russia based on measurements at two different scales and two independent upscaling approaches. Plot-scale measurements (chambers on terrestrial surfaces, gas gradient method and bubble collectors on lakes were carried out from July 2007 to October 2008. The landscape-scale eddy covariance (EC measurements covered the snow-free period of 2008. The annual net ecosystem exchange (NEE of different land cover types ranged from −251 to 84 g C m−2. Leaf area index (LAI was an excellent predictor of the spatial variability in gross photosynthesis (GP, NEE and ecosystem respiration (ER. The plot-scale CO2 fluxes were first scaled up to the EC source area and then to the whole study area using two data sets: a land cover classification and a LAI map, both based on field data and a 2.4 m pixel-sized QuickBird satellite image. The good agreement of the CO2 balances for the EC footprint based on the different measuring techniques (−105 to −81 g C m−2 vs. −79 g C m−2; growing season 2008 justified the integration of the plot-scale measurements over the larger area. The regional CO2 balance based on area-integrated plot-scale measurements was −41 or −79 g C m−2 yr−1 according to the two upscaling methods, the land cover classification and the LAI map, respectively. Due to the heterogeneity of tundra, the effect of climate change on CO2 uptake will vary strongly according to the land cover type and, moreover, likely changes in their relative coverage in the future will have great impact on the regional CO2 balance.

  18. Optimal Sleep Duration in the Subarctic with Respect to Obesity Risk Is 8-9 Hours: e56756

    National Research Council Canada - National Science Library

    May Trude Johnsen; Rolf Wynn; Trond Bratlid

    2013-01-01

    ...) and abdominal obesity. The optimal sleep duration regarding BMI has previously been found to be 7-8 hours, but these studies have not been carried out in the subarctic or have lacked some central variables...

  19. Exascale Co-Design Center for Materials in Extreme Environments (ExMatEx) Annual Report - Year 2

    Energy Technology Data Exchange (ETDEWEB)

    Germann, T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Richards, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); McPherson, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Belak, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2013-11-25

    All activities of the Exascale Co-design Center for Materials in Extreme Environments (Ex- MatEx) are focused on the two ultimate goals of the project: (1) demonstrating and delivering a prototype scale-bridging materials science application based upon adaptive physics refinement, and (2) identifying the requirements for the exascale ecosystem that are necessary to perform computational materials science simulations (both single- and multi-scale). During the first year of ExMatEx, our focus was on establishing how we do computational materials science, by developing an initial suite of flexible proxy applications. These “proxy apps” are the primary vehicle for the co-design process, involving assessments and tradeoff evaluations both within the ExMatEx team, and with the entire exascale ecosystem. These interactions have formed the basis of our second year activities. The set of artifacts from these co-design interactions are the lessons learned, that are used to re-express the applications and algorithms within the context of emerging architectures, programming models, and runtime systems.

  20. Annual Energy Review, 2008

    Energy Technology Data Exchange (ETDEWEB)

    None

    2009-06-01

    The Annual Energy Review (AER) is the Energy Information Administration's (EIA) primary report of annual historical energy statistics. For many series, data begin with the year 1949. Included are statistics on total energy production, consumption, trade, and energy prices; overviews of petroleum, natural gas, coal, electricity, nuclear energy, renewable energy, and international energy; financial and environment indicators; and data unit conversions.

  1. Genomics Encyclopedia of Bacteria and Archaea-Root Nodule Bacteria (GEBA-RNB): a resource for microsymbiont genomes (2013 DOE JGI Genomics of Energy and Environment 8th Annual User Meeting)

    Energy Technology Data Exchange (ETDEWEB)

    Reeve, Wayne [Murdoch University

    2013-03-01

    Wayne Reeve of Murdoch University on "Genomics Encyclopedia of Bacteria and Archaea-Root Nodule Bacteria (GEBA-RNB): a resource for microsymbiont genomes" at the 8th Annual Genomics of Energy & Environment Meeting on March 27, 2013 in Walnut Creek, Calif.

  2. Doubled volatile organic compound emissions from subarctic tundra under simulated climate warming

    DEFF Research Database (Denmark)

    Faubert, Patrick; Tiiva, Paivi; Rinnan, Åsmund

    2010-01-01

    • Biogenic volatile organic compound (BVOC) emissions from arctic ecosystems are important in view of their role in global atmospheric chemistry and unknown feedbacks to global warming. These cold ecosystems are hotspots of climate warming, which will be more severe here than averaged over...... the globe. We assess the effects of climatic warming on non-methane BVOC emissions from a subarctic heath. • We performed ecosystem-based chamber measurements and gas chromatography-mass spectrometry (GC-MS) analyses of the BVOCs collected on adsorbent over two growing seasons at a wet subarctic tundra...... of a focus on BVOC emissions during climate change. The observed changes have implications for ecological interactions and feedback effects on climate change via impacts on aerosol formation and indirect greenhouse effects....

  3. Barcoding the Collembola of Churchill: a molecular taxonomic reassessment of species diversity in a sub-Arctic area.

    Science.gov (United States)

    Porco, David; Skarżyński, Dariusz; Decaëns, Thibaud; Hebert, Paul D N; Deharveng, Louis

    2014-03-01

    Although their functional importance in ecosystems is increasingly recognized, soil-dwelling micro-arthropods are usually poorly known in comparison with their above-ground counterparts. Collembola constitute a significant and species-rich component of the soil biodiversity, but it remains a woefully understudied group because of the taxonomic impediment. The ever-increasing use of molecular taxonomic tools, such as DNA barcoding, provides a possible solution. Here, we test the use of this approach through a diversity survey of Collembola from the vicinity of Churchill, Manitoba, Canada, and compare the results with previous surveys in the same area and in other sub-Arctic regions. The systematic barcoding campaign at Churchill revealed a diverse collembolan fauna consisting of 97 species-level MOTUs in six types of habitats. If all these MOTUs are confirmed as species, this richness would be far higher than prior records for Arctic Canada and could lead to reconsider the actual diversity of the group in Arctic environments. © 2013 John Wiley & Sons Ltd.

  4. Extensive forest leaf area survey aiming at detection of vegetation change in subarctic-boreal zone

    OpenAIRE

    Kusakabe,Tomoko; Tsuzuki,Hayato; Hughes,Gary; Sweda,Tatsuo

    2000-01-01

    The warming resulting from increasing anthropogenic carbon dioxide and other greenhouse gasses is expected to be most prominent in the subarctic-boreal region of the Northern Hemisphere. With the objective of setting up a baseline to monitor possible vegetation change in this region, a continuous vegetation profile extending 600km from Edmonton, Alberta to Cluff Lake, Saskatchewan, Canada was measured using an airborne infrared laser altimeter mounted on a helicopter. Then the distribution of...

  5. Recent changes in aquatic biota in subarctic Fennoscandia - the role of global and local environmental variables

    Science.gov (United States)

    Weckström, Jan; Leppänen, Jaakko; Sorvari, Sanna; Kaukolehto, Marjut; Weckström, Kaarina; Korhola, Atte

    2013-04-01

    The Arctic, representing a fifth of the earth's surface, is highly sensitive to the predicted future warming and it has indeed been warming up faster than most other regions. This makes the region critically important and highlights the need to investigate the earliest signals of global warming and its impacts on the arctic and subarctic aquatic ecosystems and their biota. It has been demonstrated that many Arctic freshwater ecosystems have already experienced dramatic and unpreceded regime shifts during the last ca. 150 years, primarily driven by climate warming. However, despite the indisputable impact of climate-related variables on freshwater ecosystems other, especially local-scale catchment related variables (e.g. geology, vegetation, human activities) may override the climate signal and become the primary factor in shaping the structure of aquatic ecosystems. Although many studies have contributed to an improved understanding of limnological and hydrobiological features of Artic and subarctic lakes, much information is still needed especially on the interaction between the biotic and abiotic components, i.e. on factors controlling the food web dynamics in these sensitive aquatic ecosystems. This is of special importance as these lakes are of great value in water storage, flood prevention, and maintenance of biodiversity, in addition to which they are vital resources for settlement patterns, food production, recreation, and tourism. In this study we compare the pre-industrial sediment assemblages of primary producers (diatoms and Pediastrum) and primary consumers (cladoceran and chironomids) with their modern assemblages (a top-bottom approach) from 50 subarctic Fennoscandian lakes. We will evaluate the recent regional pattern of changes in aquatic assemblages, and assess how coherent the lakes' responses are across the subarctic area. Moreover, the impact of global (e.g. climate, precipitation) and local (e.g. lake and its catchment characteristics) scale

  6. Enhanced subarctic Pacific stratification and nutrient utilization during glacials over the last 1.2 Myr

    Science.gov (United States)

    Knudson, Karla P.; Ravelo, Ana Christina

    2015-11-01

    The relationship between climate, biological productivity, and nutrient flux is of considerable interest in the subarctic Pacific, which represents an important high-nitrate, low-chlorophyll region. While previous studies suggest that changes in iron supply and/or physical ocean stratification could hypothetically explain orbital-scale fluctuations in subarctic Pacific nutrient utilization and productivity, previous records of nutrient utilization are too short to evaluate these relationships over many glacial-interglacial cycles. We present new, high-resolution records of sedimentary δ15N, which offer the first opportunity to evaluate systematic, orbital-scale variations in subarctic Pacific nitrate utilization from 1.2 Ma. Nitrate utilization was enhanced during all glacials, varied with orbital-scale periodicity since the mid-Pleistocene transition, was strongly correlated with enhanced aeolian dust and low atmospheric CO2, but was not correlated with productivity. These results suggest that glacial stratification, rather than iron fertilization, systematically exerted an important regional control on nutrient utilization and air-sea carbon flux.

  7. Foliar Expression of Parent Lithologic Composition in the Sub-Arctic: Examples from Heath Ecosystems of Abisko, Sweden.

    Science.gov (United States)

    Heim, E. W.; Tomczyk, N.; Remiszewski, K.; Bryce, J. G.; Frey, S. D.; Prado, M. F.; Varner, R. K.

    2014-12-01

    Climatic evolution and its effect on ecosystem stability through macronutrient acquisition is of particular interest in the fringe ecosystems of the Arctic and Sub-Arctic, regions predicted to face the most extreme temperature increases in Earth's changing climate. Accordingly enhanced understanding of climate change impacts on nutrient mobilization in recently glaciated terrains will factor importantly into accurate predictive models for future ecosystem health. Lithologic variation can lead to differences in geomorphic processes and thus influence landscape evolution [1]. Heath ecosystems in the region are developed on thin soils which place them close to parent material bedrock. Given the abundance of thin soils mantling bedrock, we assessed how bedrock geochemical content links with foliar composition of key macronutrients. We focused our studies on four sites near Abisko, Sweden (68°21'N 19°02'E) in metamorphosed sedimentary bedrock. In our sites the average annual air temperature has crossed the 0o threshold and has been linked to many cryospheric and ecological impacts [2]. Sites were chosen at the same elevation (700 m absl) and shared similar vegetation coverage. Three dominant species across our sampling sites include Betula nana, Empetrum nigrum, and Salix lapponum. E. Nigrum had consistent concentrations of foliar magnesium (Mg) and phosphorus (P) across the bedrock compositional gradients. B. nana and S. lapponum had consistently higher foliar Mg and P concentrations than E. nigrum across the gradients. Across a soil calcium (Ca) gradient, dominant species had a weak correlation between soil Ca and foliar Ca contents, R2 = 0.106. Soil Mg and P gradients were similarly poorly correlated with foliar abundances, R2 = -0.0228, and R2= -0.034 respectively. Expansion of our work into other lithologies will contribute towards improved predictive biogeochemical models of macronutrient acquisition and ecological evolution across changing Arctic ecosystems.

  8. Remediation of metal-contaminated land for plant cultivation in the Arctic/subarctic region

    Science.gov (United States)

    Kikuchi, Ryunosuke; Gorbacheva, Tamara T.; Ferreira, Carla S.

    2017-04-01

    Hazardous activities and/or industries involve the use, storage or disposal of hazardous substances. These substances can sometimes contaminate the soil, which can remain contaminated for many years. The metals can have severe effects of on ecosystems. In the Arctic/subarctic regions, the Kola Peninsula (66-70°N and 28°30'-41°30'E) in Russia is one of the seriously polluted regions: close to the nickel-copper smelters, the deposition of metal pollutants has severely damaged the soil and ground vegetation, resulting in a desert area. An area of 10-15 km around the smelters on the Kola Peninsula is today dry sandy and stony ground. A great amount of financial aid is usually required to recover theland. Considering cost performance, a pilot-scale (4ha) field test was carried out to investigate how to apply municipal sewage sludge for rehabilitation of degraded land near the Ni-Cu smelter complex on the Kola Peninsula. The above-mentioned field test for soil rehabilitation was performed while smelting activities were going on; thus, the survey fields were suffering from pollution emitted by the metallurgical industry, and may continue to suffer in the future. After the composting of sewage sludge, the artificial substratum made from the compost was introduced to the test field for the polluted-land remediation, and then willows, birches and grasses were planted on the substratum. The following remarkable points in pollution load were observed between the background field and the rehabilitation test field (e.g. polluted land): (i) the annual precipitation amount of SO42- (5668 g/ha) in the rehabilitation test field was over 5 times greater than that in the background field; (ii) the Pb amount (1.5 g/ha) in the rehabilitation test field was 29 times greater than that in the background field; (iii) the Co amount (10.9 g/ha) in the rehabilitation test field was 54 times greater than that in the background field; (iv) the Cu amount (752 g/ha) in the rehabilitation field

  9. Radioactive foodchains in the subarctic environment. Progress report, November 15, 1977--November 14, 1978. [Leading abstract

    Energy Technology Data Exchange (ETDEWEB)

    Miettinen, J K

    1978-08-01

    Separate abstracts were prepared for seven of the eight sections in this report. The eighth section is an introductory paper discussing the nature of the investigations and the data presented in the other seven papers. (ERB)

  10. Terrigenous fluxes of pollen, insect scale and land plant palynodebris observed by sediment traps deployed in the subarctic Pacific

    Science.gov (United States)

    Tsutsui, H.; Takahashi, K.; Matsuoka, K.; Jordan, R. W.; Yamamoto, S.

    2016-02-01

    From 1990 to 2009, sediment traps were deployed and recovered in the subarctic Pacific (Station SA; 49°N, 174°W) during each summer, allowing the long-term observation of particle fluxes. As the Pacific Decadal Oscillation index changed in 1999 while air temperatures cooled, this study focused on pollen, land plant debris and insect scale fluxes during 1994 to 2009 at Station SA. The maximum pollen and fern spores flux was 644 grains m2 d-1, with a mean of 74 grains m2 d-1and the following details: 65% of the total pollen counts represented by wind-pollinated trees (e.g., alder, birch and pine), 24% by the herbaceous plants, and 11% by fern spores. Spore, herbaceous and wind-pollinated tree pollen fluxes peaked primarily in May (and sporadically also in April and June) and September-October. The annual flux peaks of insect scales (of unknown origin) and land-plant debris were in May and September, but over the entire study period the maximum insect scale flux of 161 scales m2 d-1 was in August 2002, with a mean of 16 scales m2 d-1. Furthermore, the maximum (in August 2004) and mean land-plant debris fluxes were 107 and 10 plant fragments m2 d-1, respectively. The sediment traps were situated at southern side of the Aleutian Islands, where snow and ice occurred for six months from October to May. The ice-snow season accounts for 25% of the total annual particle flux, with 75% throughout the rest of the year. The correlation coefficient among pollen, insect scales and land plant debris are: 1) 0.58 (probability <1%) between wind-pollinated plant pollen and insect scales, and 2) 0.75 (probability <5%) between herbaceous plant pollen and land plant debris. The production locations, residence time, routes and mode of transport of the particles are important factors. The pollen fluxes observed during April to June appeared to have originated from the Western Alaska, but during the rest of years they appeared to have been from the eastern Russia. That pollen and other

  11. Radiocesium in the western subarctic area of the North Pacific Ocean, Bering Sea, and Arctic Ocean in 2013 and 2014.

    Science.gov (United States)

    Kumamoto, Yuichiro; Aoyama, Michio; Hamajima, Yasunori; Nishino, Shigeto; Murata, Akihiko; Kikuchi, Takashi

    2017-08-01

    We measured radiocesium ( 134 Cs and 137 Cs) in seawater from the western subarctic area of the North Pacific Ocean, Bering Sea, and Arctic Ocean in 2013 and 2014. Fukushima-derived 134 Cs in surface seawater was observed in the western subarctic area and Bering Sea but not in the Arctic Ocean. Vertical profile of 134 Cs in the Canada Basin of the Arctic Ocean implies that Fukushima-derived 134 Cs intruded into the basin from the Bering Sea through subsurface (150m depth) in 2014. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Optimal sleep duration in the subarctic with respect to obesity risk is 8-9 hours.

    Directory of Open Access Journals (Sweden)

    May Trude Johnsen

    Full Text Available INTRODUCTION: Sleep duration, chronotype and social jetlag have been associated with body mass index (BMI and abdominal obesity. The optimal sleep duration regarding BMI has previously been found to be 7-8 hours, but these studies have not been carried out in the subarctic or have lacked some central variables. The aims of our study were to examine the associations between sleep variables and body composition for people living in the subarctic, taking a range of variables into consideration, including lifestyle variables, health variables and biological factors. METHODS: The cross sectional population Tromsø Study was conducted in northern Norway, above the Arctic Circle. 6413 persons aged 30-65 years completed questionnaires including self-reported sleep times, lifestyle and health. They also measured height, weight, waist and hip circumference, and biological factors (non-fasting serum level of cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides and glucose. The study period was from 1 October 2007 to 19 December 2008. RESULTS: The optimal sleep length regarding BMI and waist circumference was found to be 8-9 hours. Short sleepers (<6 h had about 80% increased risk of being in the BMI≥25 kg/m2 group and male short sleepers had doubled risk of having waist circumference ≥102 cm compared to 8-9 hours sleepers. We found no impact of chronotype or social jetlag on BMI or abdominal obesity after controlling for health, lifestyle, and biological parameters. CONCLUSIONS: In our subarctic population, the optimal sleep duration time regarding risk of overweight and abdominal obesity was 8-9 hours, which is one hour longer compared to findings from other studies. Short sleepers had 80% increased risk of being overweight, and men had a doubled risk of having abdominal obesity. We found no associations between chronotype or social jetlag and BMI or abdominal obesity, when we took a range of life-style, health and biological variables into

  13. Tolerance of an expanding subarctic shrub, Betula glandulosa, to simulated caribou browsing.

    Directory of Open Access Journals (Sweden)

    Emilie Champagne

    Full Text Available Densification of the shrub layer has been reported in many subarctic regions, raising questions about the implication for large herbivores and their resources. Shrubs can tolerate browsing and their level of tolerance could be affected by browsing and soils productivity, eventually modifying resource availability for the caribou. Our objective was to assess the compensatory growth potential of a subarctic shrub, Betula glandulosa Michx., in relation with caribou browsing and nutriment availability for the plants. We used a simulated browsing (0, 25 and 75% of available shoots and nitrogen-fertilisation (0 and 10 g m(-2 experiment to test two main hypotheses linking tolerance to resource availability, the Compensatory Continuum Hypothesis and the Growth Rate Hypothesis as well as the predictions from the Limiting Resource Model. We seek to explicitly integrate the relative browsing pressure in our predictions since the amount of tissues removed could affect the capacity of long-lived plants to compensate. Birches fully compensated for moderate browsing with an overall leaf biomass similar to unbrowsed birches but undercompensated under heavy browsing pressure. The main mechanism explaining compensation appears to be the conversion of short shoots into long shoots. The leaf area increased under heavy browsing pressure but only led to undercompensation. Fertilisation for two consecutive years did not influence the response of birch, thus we conclude that our results support the LRM hypothesis of equal tolerance under both high and low nitrogen availability. Our results highlight that the potential for compensatory growth in dwarf birch is surpassed under heavy browsing pressure independently of the fertilisation regime. In the context of the worldwide decline in caribou herds, the reduction in browsing pressure could act synergistically with global climate change to promote the current shrub expansion reported in subarctic regions.

  14. Tolerance of an Expanding Subarctic Shrub, Betula glandulosa, to Simulated Caribou Browsing

    Science.gov (United States)

    Champagne, Emilie; Tremblay, Jean-Pierre; Côté, Steeve D.

    2012-01-01

    Densification of the shrub layer has been reported in many subarctic regions, raising questions about the implication for large herbivores and their resources. Shrubs can tolerate browsing and their level of tolerance could be affected by browsing and soils productivity, eventually modifying resource availability for the caribou. Our objective was to assess the compensatory growth potential of a subarctic shrub, Betula glandulosa Michx., in relation with caribou browsing and nutriment availability for the plants. We used a simulated browsing (0, 25 and 75% of available shoots) and nitrogen-fertilisation (0 and 10 g m−2) experiment to test two main hypotheses linking tolerance to resource availability, the Compensatory Continuum Hypothesis and the Growth Rate Hypothesis as well as the predictions from the Limiting Resource Model. We seek to explicitly integrate the relative browsing pressure in our predictions since the amount of tissues removed could affect the capacity of long-lived plants to compensate. Birches fully compensated for moderate browsing with an overall leaf biomass similar to unbrowsed birches but undercompensated under heavy browsing pressure. The main mechanism explaining compensation appears to be the conversion of short shoots into long shoots. The leaf area increased under heavy browsing pressure but only led to undercompensation. Fertilisation for two consecutive years did not influence the response of birch, thus we conclude that our results support the LRM hypothesis of equal tolerance under both high and low nitrogen availability. Our results highlight that the potential for compensatory growth in dwarf birch is surpassed under heavy browsing pressure independently of the fertilisation regime. In the context of the worldwide decline in caribou herds, the reduction in browsing pressure could act synergistically with global climate change to promote the current shrub expansion reported in subarctic regions. PMID:23272191

  15. The Atmosphere's Imprint on the Hydrologic and Carbon Cycle in the Alaskan Arctic and Subarctic

    Science.gov (United States)

    Nichols, J. E.; Peteet, D. M.; Moy, C. M.

    2011-12-01

    The Alaskan arctic and subarctic is a region rich with terrestrial carbon stored in peatlands which have been accumulating thoughout the Holocene. Such peatlands are important players in the terrestrial carbon cycle. One major influence on the amount of carbon stored in peatlands is the amount and seasonality of precipitation, which is controlled, in turn, by changes in atmospheric circulation. The Holocene changes in atmospheric circulation over the North Pacific, and the Gulf of Alaska in particular is poorly understood. In the case of the Alaskan subarctic, for example, the Aleutian Low is an important driver of moisture balance change. Further, changes in the Aleutian low also control fluxes of important micronutrients such as iron from the land surface to the Gulf of Alaska, an area of the ocean where phytoplankton growth is iron limited. We reconstructed the hydrogen isotopes of precipitation, the amount of surface evaporation, and the overall moisture balance through the Holocene at three peatland sites in the Alaskan arctic and subarctic: Goldmine Bog, Fairbanks, (65°N, 147°W), Phalarope Bog, Kodiak (57°N, 154°W), and Bear Bog, Cordova (60°N, 145°W). These data reveal large, regionally consistent changes in atmospheric circulation throughout the Holocene that play an important role in changing the amount of carbon stored in peatlands. Understanding the relationships among atmospheric circulation, the hydrologic cycle, and the carbon cycle in the past provide an important guide for predicting the carbon cycle changes that will result from future climate warming.

  16. Both seed germination and seedling mortality increase with experimental warming and fertilization in a subarctic tundra

    Science.gov (United States)

    Vandeplas, Nicolas; Kockelbergh, Fred; Nijs, Ivan

    2017-01-01

    Abstract Climate change is expected to force many species in arctic regions to migrate and track their climatic niche. This requires recruitment from seed, which currently shows very low rates in arctic regions, where long-lived and vegetatively reproducing plants dominate. Therefore, we pose the question whether recruitment (germination and seedling establishment) in arctic regions will significantly improve in a warmer world, and thus allow species to follow their climatic niche. We used a full factorial experiment to examine if realistic warmer temperatures (+3 °C; infrared radiation) and increased nitrogen availability (+1.4 g N m−2 year−1) affected germination, seedling survival and above- and below-ground seedling biomass in five species common in subarctic regions (Anthoxanthum odoratum, Betula nana, Pinus sylvestris, Solidago virgaurea, Vaccinium myrtillus). We found that warming increased seedling emergence in all species, but that subsequent mortality also increased, resulting in no net warming effect on seedling establishment. Warming slightly increased above-ground seedling biomass. Fertilization, on the other hand, did not influence seedling biomass, but it increased seedling establishment in B. nana while it reduced establishment in V. myrtillus. This may help B. nana dominate over V. myrtillus in warmer tundra. Surprisingly, no interactive effects between warming and fertilization were found. The lack of a general positive response of seedling establishment to warmer and more nutrient-rich conditions suggests that (sub)arctic species may experience difficulties in tracking their climatic niche. Predictions of future species distributions in arctic regions solely based on abiotic factors may therefore overestimate species’ ranges due to their poor establishment. Also, the opposite response to fertilization of two key (sub)arctic dwarf shrubs, i.e. B. nana and V. myrtillus, could have important implications for the future development of arctic

  17. Geographic Distribution of Ammonia-Oxidizing Archaea along the Kuril Islands in the Western Subarctic Pacific

    Directory of Open Access Journals (Sweden)

    Hongmei Jing

    2017-06-01

    Full Text Available Community composition and abundance of ammonia-oxidizing archaea (AOA in the ocean were affected by different physicochemical conditions, but their responses to physical barriers (such as a chain of islands were largely unknown. In our study, geographic distribution of the AOA from the surface photic zone to the deep bathypelagic waters in the western subarctic Pacific adjacent to the Kuril Islands was investigated using pyrosequencing based on the ammonia monooxygenase subunit A (amoA gene. Genotypes of clusters A and B dominated in the upper euphotic zone and the deep waters, respectively. Quantitative PCR assays revealed that the occurrence and ammonia-oxidizing activity of ammonia-oxidizing archaea (AOA reached their maxima at the depth of 200 m, where a higher diversity and abundance of actively transcribed AOA was observed at the station located in the marginal sea exposed to more terrestrial input. Similar community composition of AOA observed at the two stations adjacent to the Kuril Islands maybe due to water exchange across the Bussol Strait. They distinct from the station located in the western subarctic gyre, where sub-cluster WCAII had a specific distribution in the surface water, and this sub-cluster seemed having a confined distribution in the western Pacific. Habitat-specific groupings of different WCB sub-clusters were observed reflecting the isolated microevolution existed in cluster WCB. The effect of the Kuril Islands on the phylogenetic composition of AOA between the Sea of Okhotsk and the western subarctic Pacific is not obvious, possibly because our sampling stations are near to the Bussol Strait, the main gateway through which water is exchanged between the Sea of Okhotsk and the Pacific. The vertical and horizontal distribution patterns of AOA communities among stations along the Kuril Islands were essentially determined by the in situ prevailing physicochemical gradients along the two dimensions.

  18. Optimal sleep duration in the subarctic with respect to obesity risk is 8-9 hours.

    Science.gov (United States)

    Johnsen, May Trude; Wynn, Rolf; Bratlid, Trond

    2013-01-01

    Sleep duration, chronotype and social jetlag have been associated with body mass index (BMI) and abdominal obesity. The optimal sleep duration regarding BMI has previously been found to be 7-8 hours, but these studies have not been carried out in the subarctic or have lacked some central variables. The aims of our study were to examine the associations between sleep variables and body composition for people living in the subarctic, taking a range of variables into consideration, including lifestyle variables, health variables and biological factors. The cross sectional population Tromsø Study was conducted in northern Norway, above the Arctic Circle. 6413 persons aged 30-65 years completed questionnaires including self-reported sleep times, lifestyle and health. They also measured height, weight, waist and hip circumference, and biological factors (non-fasting serum level of cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides and glucose). The study period was from 1 October 2007 to 19 December 2008. The optimal sleep length regarding BMI and waist circumference was found to be 8-9 hours. Short sleepers (hours sleepers. We found no impact of chronotype or social jetlag on BMI or abdominal obesity after controlling for health, lifestyle, and biological parameters. In our subarctic population, the optimal sleep duration time regarding risk of overweight and abdominal obesity was 8-9 hours, which is one hour longer compared to findings from other studies. Short sleepers had 80% increased risk of being overweight, and men had a doubled risk of having abdominal obesity. We found no associations between chronotype or social jetlag and BMI or abdominal obesity, when we took a range of life-style, health and biological variables into consideration.

  19. Fatal hypothermia: an analysis from a sub-arctic region

    Directory of Open Access Journals (Sweden)

    Helge Brändström

    2012-05-01

    Full Text Available Objectives. To determine the incidence as well as contributing factors to fatal hypothermia. Study design. Retrospective, registry-based analysis. Methods. Cases of fatal hypothermia were identified in the database of the National Board of Forensic Medicine for the 4 northernmost counties of Sweden and for the study period 1992–2008. Police reports, medical records and autopsy protocols were studied. Results. A total of 207 cases of fatal hypothermia were noted during the study period, giving an annual incidence of 1.35 per 100,000 inhabitants. Seventy-two percent occurred in rural areas, and 93% outdoors. Many (40% were found within approximately 100 meters of a building. The majority (75% occurred during the colder season (October to March. Some degree of paradoxical undressing was documented in 30%. Ethanol was detected in femoral vein blood in 43% of the victims. Contributing co-morbidity was common and included heart disease, earlier stroke, dementia, psychiatric disease, alcoholism, and recent trauma. Conclusions. With the identification of groups at high risk for fatal hypothermia, it should be possible to reduce risk through thoughtful interventions, particularly related to the highest risk subjects (rural, living alone, alcohol-imbibing, and psychiatric diagnosis-carrying citizens.

  20. Animistic pragmatism and native ways of knowing: adaptive strategies for overcoming the struggle for food in the sub-Arctic

    Directory of Open Access Journals (Sweden)

    Raymond Anthony

    2013-08-01

    Full Text Available Background. Subsistence norms are part of the “ecosophy” or ecological philosophy of Alaska Native Peoples in the sub-Arctic, such as the Inupiat of Seward Peninsula. This kind of animistic pragmatism is a special source of practical wisdom that spans over thousands of years and which has been instrumental in the Iñupiat’s struggle to survive and thrive in harsh and evolving environments. Objective. I hope to show how narrative in relationship to the “ecosophy” of Alaska Native peoples can help to promote a more ecological orientation to address food insecurity in rural communities in Alaska. Alaska Native ecosophy recommends central values and virtues necessary to help address concerns in Alaska’s rural communities. Design. Here, I will tease out the nature of this “ecosophy” in terms of animistic pragmatism and then show why this form of pragmatism can be instrumental for problematizing multi-scalar, intergenerational, uncertain and complex environmental challenges like food security. Results. Native elders have been the embodiment of trans-generational distributed cognition,1 for example, collective memory, norms, information, knowledge, technical skills and experimental adaptive strategies. They are human “supercomputers,” historical epistemologists and moral philosophers of a sort who use narrative, a form of moral testimony, to help their communities face challenges and seize opportunities in the wake of an ever-changing landscape. Conclusions. The “ecosophy” of the Iñupiat of Seward Peninsula offers examples of “focal practices”, which are essential for environmental education. These focal practices instil key virtues, namely humility, gratitude, self-reliance, attentiveness, responsibility and responsiveness, that are necessary for subsistence living.

  1. Feeding ecology of mesopelagic zooplankton of the subtropical and subarctic North Pacific Ocean determined with fatty acid biomarkers

    Science.gov (United States)

    Wilson, S. E.; Steinberg, D. K.; Chu, F.-L. E.; Bishop, J. K. B.

    2010-10-01

    Mesopelagic zooplankton may meet their nutritional and metabolic requirements in a number of ways including consumption of sinking particles, carnivory, and vertical migration. How these feeding modes change with depth or location, however, is poorly known. We analyzed fatty acid (FA) profiles to characterize zooplankton diet and large particle (>51 μm) composition in the mesopelagic zone (base of euphotic zone -1000 m) at two contrasting time-series sites in the subarctic (station K2) and subtropical (station ALOHA) Pacific Ocean. Total FA concentration was 15.5 times higher in zooplankton tissue at K2, largely due to FA storage by seasonal vertical migrators such as Neocalanus and Eucalanus. FA biomarkers specific to herbivory implied a higher plant-derived food source at mesotrophic K2 than at oligotrophic ALOHA. Zooplankton FA biomarkers specific to dinoflagellates and diatoms indicated that diatoms, and to a lesser extent, dinoflagellates were important food sources at K2. At ALOHA, dinoflagellate FAs were more prominent. Bacteria-specific FA biomarkers in zooplankton tissue were used as an indicator of particle feeding, and peaks were recorded at depths where known particle feeders were present at ALOHA (e.g., ostracods at 100-300 m). In contrast, depth profiles of bacterial FA were relatively constant with depth at K2. Diatom, dinoflagellate, and bacterial biomarkers were found in similar proportions in both zooplankton and particles with depth at both locations, providing additional evidence that mesopelagic zooplankton consume sinking particles. Carnivory indices were higher and increased significantly with depth at ALOHA, and exhibited distinct peaks at K2, representing an increase in dependence on other zooplankton for food in deep waters. Our results indicate that feeding ecology changes with depth as well as by location. These changes in zooplankton feeding ecology from the surface through the mesopelagic zone, and between contrasting environments

  2. Estimate of the trophic status of subarctic Imandra Lake

    Directory of Open Access Journals (Sweden)

    Terent'eva I. A.

    2017-03-01

    Full Text Available The object of study is Imandra Lake – the largest reservoir of the Murmansk region. The lake is being influenced by the long-term and multi-factorial activities of mining and ore processing industries, air pollution and energetics. Moreover, the drain of municipal sewage from the large settlements situated on the lake's watershed makes a serious contribution to water pollution. As a result the lake has accumulated a significant amount of pollutants and nutrients that resulted currently in an increase of the toxic load on the lake system. One of the main ecological problems also is the intensification of the anthropogenic eutrophication processes. The aim of this study is to evaluate the current trophic status of Imandra Lake using the trophic index (TSI with the average annual values of the parameters: chlorophyll, total nitrogen, total phosphorus, and total organic carbon and to find the dynamics of these parameters' changes during more than 20-year period. The study of the trophic status of Imandra Lake has been performed for the period 1991–2013 yrs. using the trophic state index developed by Carlson, Kratzer and Bresonik, Dunalska. According to the calculated values of the indexes Bolshaja Imandra Lake corresponds to eutrophic-mesotrophic trophic status, Yokostrovskaya Imandra Lake could be described as mesotrophic. Babinskaja Imandra Lake that subjected to essential nutrient loading is close to the oligotrophic trophic status. However, some parts of Babinskaja Imandra Lake refer to the mesotrophic state due to influence of industrial, household and heated water of the Kola atomic power station. Thus, this part of Imadra Lake could be considered as a meso-oligotrophic status. It has been established that currently nitrogen is a limiting factor for development of algae in Imandra Lake. Based on the mathematical Vollenweider model the critical phosphorus loading values to control such an important nutrient element as phosphorus have been

  3. Acceleration of cyanobacterial dominance in north temperate-subarctic lakes during the Anthropocene.

    Science.gov (United States)

    Taranu, Zofia E; Gregory-Eaves, Irene; Leavitt, Peter R; Bunting, Lynda; Buchaca, Teresa; Catalan, Jordi; Domaizon, Isabelle; Guilizzoni, Piero; Lami, Andrea; McGowan, Suzanne; Moorhouse, Heather; Morabito, Giuseppe; Pick, Frances R; Stevenson, Mark A; Thompson, Patrick L; Vinebrooke, Rolf D

    2015-04-01

    Increases in atmospheric temperature and nutrients from land are thought to be promoting the expansion of harmful cyanobacteria in lakes worldwide, yet to date there has been no quantitative synthesis of long-term trends. To test whether cyanobacteria have increased in abundance over the past ~ 200 years and evaluate the relative influence of potential causal mechanisms, we synthesised 108 highly resolved sedimentary time series and 18 decadal-scale monitoring records from north temperate-subarctic lakes. We demonstrate that: (1) cyanobacteria have increased significantly since c. 1800 ce, (2) they have increased disproportionately relative to other phytoplankton, and (3) cyanobacteria increased more rapidly post c. 1945 ce. Variation among lakes in the rates of increase was explained best by nutrient concentration (phosphorus and nitrogen), and temperature was of secondary importance. Although cyanobacterial biomass has declined in some managed lakes with reduced nutrient influx, the larger spatio-temporal scale of sedimentary records show continued increases in cyanobacteria throughout the north temperate-subarctic regions. © 2015 John Wiley & Sons Ltd/CNRS.

  4. Unexpected differences in the population genetics of phasmavirids (Bunyavirales) from subarctic ponds.

    Science.gov (United States)

    Ballinger, Matthew J; Medeiros, Andrew S; Qin, Jie; Taylor, Derek J

    2017-01-01

    Little is known of the evolution of RNA viruses in aquatic systems. Here, we assess the genetic connectivity of two bunyaviruses (Kigluaik phantom orthophasmavirus or KIGV and Nome phantom orthophasmavirus or NOMV) with zooplanktonic hosts from subarctic ponds. We expected weak genetic structure among populations as the hosts (phantom midges) have a terrestrial winged dispersal stage. To test whether their respective viruses mirror this structure, we collected and analyzed population datasets from 21 subarctic freshwater ponds and obtained sequences from all four genes in the viral genomes. Prevalence averaged 66 per cent for 514 host specimens and was not significantly different between recently formed thaw ponds and glacial ponds. Unexpectedly, KIGV from older ponds showed pronounced haplotype divergence with little evidence of genetic connectivity. However, KIGV populations from recent thaw ponds appeared to be represented by a closely related haplotype group, perhaps indicating a genotypic dispersal bias. Unlike KIGV, NOMV had modest structure and diversity in recently formed thaw ponds. For each virus, we found elevated genetic diversity relative to the host, but similar population structures to the host. Our results suggest that non-random processes such as virus-host interactions, genotypic bias, and habitat effects differ among polar aquatic RNA viruses.

  5. Evidences of Seasonal Variation in Altimetry Derived Ocean Tides in the Subarctic Ocean

    Directory of Open Access Journals (Sweden)

    Hok Sum Fok

    2013-01-01

    Full Text Available While the barotropic ocean tides in the deep ocean are well modeled to ~2 cm RMS, accurate tidal prediction in the ice-covered polar oceans and near coastal regions remain elusive. A notable reason is that the most accurate satellite altimeters (TOPEX/Jason-1/-2, whose orbits are optimized to minimize the tidal aliasing effect, have spatial coverage limited to largely outside of the polar ocean. Here, we update the assessment of tidal models using 7 contemporary global and regional models, and show that the altimetry sea surface height (SSH anomaly residual after tidal correction is 9 - 12 cm RMS in the Subarctic Ocean. We then address the hypothesis whether plausible evidence of variable tidal signals exist in the seasonally ice-covered Subarctic Ocean, where the sea ice cover is undergoing rapid thinning. We first found a difference in variance reduction for multi-mission altimeter SSH anomaly residuals during the summer and winter seasons, with the residual during winter season 15 - 30% larger than that during the summer season. Experimental seasonal ocean tide solutions derived from satellite altimetry reveals that the recovered winter and summer tidal constituents generally differ by a few cm in amplitude and tens of degrees in phase. Relatively larger seasonal tidal patterns, in particular for M2, S2 and K1 tides, have been identified in the Chukchi Sea study region near eastern Siberia, coincident with the seasonal presence and movement of sea ice.

  6. Population dynamics and life history strategies of the dominant copepods in a sub-arctic Greenlandic fjord

    DEFF Research Database (Denmark)

    Kjellerup, Sanne; Nielsen, Torkel Gissel

    Investigations of the Arctic and Sub-Arctic pelagic food web have previously focused on the copepod genus Calanus, as they often dominate the mesozooplankton community and serve as a lipid rich food source for higher trophic levels. However, if night samples are considered a different food web mi...

  7. Population dynamics and production of the small copepod Oithona spp. in a subarctic fjord of West Greenland

    DEFF Research Database (Denmark)

    Zamora-Terol, Sara; Kjellerup, Sanne; Swalethorp, Rasmus

    2014-01-01

    The small cyclopoid copepod Oithona is widely occurring in polar areas; however, knowledge of its biology and ecology is very limited. Here, we investigate the population dynamics, vertical distribution, and reproductive characteristics of Oithona spp. from late winter to summer, in a subarctic f...

  8. Variation in genetic traits of the Baltic clam Macoma balthica from a tidal gradient in the subarctic

    NARCIS (Netherlands)

    Hummel, H.; Gunther, C.P.; Bogaards, R.H.; Fedyakov, V.

    1998-01-01

    In a subarctic tidal gradient, strong heterogeneity in genetic traits of the Baltic clam Macoma balthica was found. The heterogeneity was stronger within the intertidal gradient, over a distance of only about GO mi than along a horizontal gradient over a distance of 1200 km in clams from the west

  9. Freeze-thaw regime effects on carbon and nitrogen dynamics in sub-arctic heath tundra mesocosms

    DEFF Research Database (Denmark)

    Grogan, P.; Michelsen, A.; Ambus, P.

    2004-01-01

    of which is realistic of in situ spatial and temporal variation in field conditions, on C and N dynamics in sub-arctic heath tundra mesocosms. In addition, N-15 isotopic label was used to follow the partitioning of a labile N pool between major ecosystem components, both during the freeze-thaw treatments...

  10. Changing times, changing stories: Generational differences in climate change perspectives from four remote indigenous communities in Subarctic Alaska

    Science.gov (United States)

    Nicole M. Herman-Mercer; Elli Matkin; Melinda J. Laituri; Ryan C. Toohey; Maggie Massey; Kelly Elder; Paul F. Schuster; Edda A. Mutter

    2016-01-01

    Indigenous Arctic and Subarctic communities currently are facing a myriad of social and environmental changes. In response to these changes, studies concerning indigenous knowledge (IK) and climate change vulnerability, resiliency, and adaptation have increased dramatically in recent years. Risks to lives and livelihoods are often the focus of adaptation...

  11. Experimentally increased nutrient availability at the permafrost thaw front selectively enhances biomass production of deep-rooting subarctic peatland species

    NARCIS (Netherlands)

    Keuper, Frida; Dorrepaal, Ellen; van Bodegom, Peter M.; van Logtestijn, Richard; Venhuizen, Gemma; van Hal, Jurgen; Aerts, Rien

    2017-01-01

    Climate warming increases nitrogen (N) mineralization in superficial soil layers (the dominant rooting zone) of subarctic peatlands. Thawing and subsequent mineralization of permafrost increases plant-available N around the thaw-front. Because plant production in these peatlands is N-limited, such

  12. Annotated bibliography on soil erosion and erosion control in subarctic and high-latitude regions of North America.

    Science.gov (United States)

    C.W. Slaughter; J.W. Aldrich

    1989-01-01

    This annotated bibliography emphasizes the physical processes of upland soil erosion, prediction of soil erosion and sediment yield, and erosion control. The bibliography is divided into two sections: (1) references specific to Alaska, the Arctic and subarctic, and similar high-latitude settings; and (2) references relevant to understanding erosion, sediment production...

  13. Challenges in modelling isoprene and monoterpene emission dynamics of Arctic plants: a case study from a subarctic tundra heath

    Science.gov (United States)

    Tang, Jing; Schurgers, Guy; Valolahti, Hanna; Faubert, Patrick; Tiiva, Päivi; Michelsen, Anders; Rinnan, Riikka

    2016-12-01

    The Arctic is warming at twice the global average speed, and the warming-induced increases in biogenic volatile organic compounds (BVOCs) emissions from Arctic plants are expected to be drastic. The current global models' estimations of minimal BVOC emissions from the Arctic are based on very few observations and have been challenged increasingly by field data. This study applied a dynamic ecosystem model, LPJ-GUESS, as a platform to investigate short-term and long-term BVOC emission responses to Arctic climate warming. Field observations in a subarctic tundra heath with long-term (13-year) warming treatments were extensively used for parameterizing and evaluating BVOC-related processes (photosynthesis, emission responses to temperature and vegetation composition). We propose an adjusted temperature (T) response curve for Arctic plants with much stronger T sensitivity than the commonly used algorithms for large-scale modelling. The simulated emission responses to 2 °C warming between the adjusted and original T response curves were evaluated against the observed warming responses (WRs) at short-term scales. Moreover, the model responses to warming by 4 and 8 °C were also investigated as a sensitivity test. The model showed reasonable agreement to the observed vegetation CO2 fluxes in the main growing season as well as day-to-day variability of isoprene and monoterpene emissions. The observed relatively high WRs were better captured by the adjusted T response curve than by the common one. During 1999-2012, the modelled annual mean isoprene and monoterpene emissions were 20 and 8 mg C m-2 yr-1, with an increase by 55 and 57 % for 2 °C summertime warming, respectively. Warming by 4 and 8 °C for the same period further elevated isoprene emission for all years, but the impacts on monoterpene emissions levelled off during the last few years. At hour-day scale, the WRs seem to be strongly impacted by canopy air T, while at the day-year scale, the WRs are a combined

  14. Responses of non-methane biogenic volatile organic compound emissions to climate change in boreal and subarctic ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Faubert, P.

    2010-07-01

    Non-methane biogenic volatile organic compound emissions (BVOCs) have important roles in the global atmospheric chemistry but their feedbacks to climate change are still unknown. This thesis reports one of the first estimates of BVOC emissions from boreal and subarctic ecosystems. Most importantly, this thesis assesses the BVOC emission responses to four effects of climate change in these ecosystems: (1) the direct effect of warming, and its indirect effects via (2) water table drawdown, (3) change in the vegetation composition, and (4) enhanced UV-B radiation. BVOC emissions were measured using a conventional chamber method in which the compounds were collected on adsorbent and later analyzed by gas chromatography-mass spectrometry. On a subarctic heath, warming by only 1.9-2.5 degC doubled the monoterpene and sesquiterpene emissions. Such a high increase of BVOC emissions under a conservative warming cannot be predicted by the current models, which underlines the importance of a focus on BVOC emissions from the Subarctic under climate change. On a subarctic peatland, enhanced UV-B did not affect the BVOC emissions but the water table level exerted the major effect. The water table drawdown experimentally applied on boreal peatland microcosms decreased the emissions of monoterpenes and other VOCs (BVOCs with a lifetime>1 d) for the hollows (wet microsites) and that of all BVOC groups for the lawns (moderately wet microsites). The warming treatment applied on the lawn microcosms decreased the isoprene emission. The removal of vascular plants in the hummock (dry microsites) microcosms decreased the emissions of monoterpenes while the emissions between the microcosms covered with Sphagnum moss and bare peat were not different. In conclusion, the results presented in this thesis indicate that climate change has complex effects on the BVOC emissions. These results make a significant contribution to improving the modeling of BVOC emissions for a better understanding of

  15. PICES members endure aftershocks at Third Annual Meeting

    Science.gov (United States)

    Wooster, W. S.

    On October 15-24, 1994, little more than a week after a major earthquake (8.2) struck just 90 km to the east, the North Pacific Marine Science Organization (PICES) held its Third Annual Meeting in Nemuro, northern Hokkaido, Japan. The conference center where the meeting was to be held suffered significant damage, but thanks to the prodigious efforts of the people of Nemuro, we convened in the city library and neighboring buildings. More than 200 participants from Canada, China, Japan, Korea, Mexico, Russia, and the United States experienced daily aftershocks, as they discussed major scientific questions of the subarctic Pacific ocean. Many of the papers presented concerned the impact of climate-scale variations in atmospheric and oceanic conditions on ecosystems of the region. A series of review papers on oceanography of the subarctic Pacific introduced a workshop, cosponsored by the Science and Technology Agency of Japan, that led to recommendations for monitoring changes in both physical forcing and ecosystem response.

  16. We adapt… but is it good or bad? Locating the political ecology and social-ecological systems debate in reindeer herding in the Swedish Sub-Arctic.

    NARCIS (Netherlands)

    Gallardo, Gloria; Saunders, Fred; Sokolova, Tatiana; Börebäck, Kristina; van Laerhoven, F.S.J.; Kokko, Suvi; Tuvendal, Magnus

    2017-01-01

    Abstract Reindeer herding (RDH) is a livelihood strategy deeply connected to Sami cultural tradition. This article explores the implications of two theoretical and methodological approaches for grasping complex socioenvironmental relationships of RDH in Subarctic Sweden. Based on joint fieldwork,

  17. Organic matter control on the distribution of arsenic in lake sediments impacted by ~65years of gold ore processing in subarctic Canada.

    Science.gov (United States)

    Galloway, Jennifer M; Swindles, Graeme T; Jamieson, Heather E; Palmer, Michael; Parsons, Michael B; Sanei, Hamed; Macumber, Andrew L; Timothy Patterson, R; Falck, Hendrik

    2017-10-27

    Climate change is profoundly affecting seasonality, biological productivity, and hydrology in high northern latitudes. In sensitive subarctic environments exploitation of mineral resources led to contamination and it is not known how cumulative effects of resource extraction and climate warming will impact ecosystems. Gold mines near Yellowknife, Northwest Territories, subarctic Canada, operated from 1938 to 2004 and released >20,000t of arsenic trioxide (As2O3) to the environment through stack emissions. This release resulted in elevated arsenic concentrations in lake surface waters and sediments relative to Canadian drinking water standards and guidelines for the protection of aquatic life. A meta-analytical approach is used to better understand controls on As distribution in lake sediments within a 30-km radius of historic mineral processing activities. Arsenic concentrations in the near-surface sediments range from 5mg·kg-1 to over 10,000mg·kg-1 (median 81mg·kg-1; n=105). Distance and direction from the historic roaster stack are significantly (p<0.05) related to sedimentary As concentration, with highest As concentrations in sediments within 11km and lakes located downwind. Synchrotron-based μXRF and μXRD confirm the persistence of As2O3 in near surface sediments of two lakes. Labile organic matter (S1) is significantly (p<0.05) related to As and S concentrations in sediments and this relationship is greatest in lakes within 11km from the mine. These relations are interpreted to reflect labile organic matter acting as a substrate for microbial growth and mediation of authigenic precipitation of As-sulphides in lakes close to the historic mine where As concentrations are highest. Continued climate warming is expected to lead to increased biological productivity and changes in organic geochemistry of lake sediments that are likely to play an important role in the mobility and fate of As in aquatic ecosystems. Copyright © 2017 Elsevier B.V. All rights

  18. Monitoring of the invasive diatom Didymosphenia geminata in the subarctic and in alpine areas of southern Europe

    Science.gov (United States)

    Finger, David C.; Jónsson, Ingi R.; Cypaité, Vaiva; Ognjanova, Nadja; Ólafsson, Jón S.; Trichkova, Teodora

    2016-04-01

    In recent decades invasive species have been spreading across Europe. Although the perceptions of invasive species are divergent among researchers there is a general consent that invasive species endanger the diversity of native biota and hence should be monitored to initiate appropriate counter measures in drastic cases. Anthropogenic activities and climate change are the main cause for the enhanced spreading of non-native species to new environments. In this presentation we will present preliminary results from two aquatic case studies, one located in subarctic Iceland (River Elliðaár) and one in the high mountains of Bulgaria (the Seven Rila lakes), focusing on the freshwater diatom Didymosphenia geminata (Didymo). The diatom is a single cell algae which's natural habitat is cold fresh water environments with low nutrient content, i.e. mountainous areas in Europe, Asia and North America. In the last decades Didymo has been increasingly observed in new areas, e.g. Iceland, North America and New Zealand. Within the ESENIAS-TOOLS project two field excursions will identify the existence of Didymo in the two study sites and compare current abundance to previous observations. The preliminary results in the Rila Mountains, including both fossil and recent records, confirm that the occurrence of Didymo is restricted to Lake Bliznaka, the largest of the seven lakes located at lower altitude. In River Elliðaár preliminary results indicate a high abundance of Didymo along all sampling locations, confirming the invasive proliferation described in previous studies. The upscaling of the preliminary results from Elliðaár and Rila Mountains can help us to formulate general conclusions about the spreading of this invasive species. Furthermore, this bilateral cooperation can be further extended to other countries and hence contribute to a better management of invasive alien species in Europe. Acknowledgement: This study is part of ESENIAS - The East and South European

  19. Mineralization and carbon turnover in subarctic heath soil as affected by warming and additional litter

    DEFF Research Database (Denmark)

    Rinnan, Riikka; Michelsen, Anders; Baath, Erland

    2007-01-01

    Arctic soil carbon (C) stocks are threatened by the rapidly advancing global warming. In addition to temperature, increasing amounts of leaf litter fall following from the expansion of deciduous shrubs and trees in northern ecosystems may alter biogeochemical cycling of C and nutrients. Our aim...... was to assess how factorial warming and litter addition in a long-term field experiment on a subarctic heath affect resource limitation of soil microbial communities (measured by thymidine and leucine incorporation techniques), net growing-season mineralization of nitrogen (N) and phosphorus (P), and carbon...... the field incubation. The added litter did not affect the carbon content, but it was a source of nutrients to the soil, and it also tended to increase bacterial growth rate and net mineralization of P. The inorganic N pool decreased during the field incubation of soil cores, especially in the separate...

  20. Switching predominance of organic versus inorganic carbon exports from an intermediate-size subarctic watershed

    Science.gov (United States)

    Dornblaser, Mark M.; Striegl, Robert G.

    2015-01-01

    Hydrologic exports of dissolved inorganic and organic carbon (DIC, DOC) reflect permafrost conditions in arctic and subarctic river basins. DIC yields in particular, increase with decreased permafrost extent. We investigated the influence of permafrost extent on DIC and DOC yield in a tributary of the Yukon River, where the upper watershed has continuous permafrost and the lower watershed has discontinuous permafrost. Our results indicate that DIC versus DOC predominance switches with interannual changes in water availability and flow routing in intermediate-size watersheds having mixed permafrost coverage. Large water yield and small concentrations from mountainous headwaters and small water yield and high concentrations from lowlands produced similar upstream and downstream carbon yields. However, DOC export exceeded DIC export during high-flow 2011 while DIC predominated during low-flow 2010. The majority of exported carbon derived from near-surface organic sources when landscapes were wet or frozen and from mineralized subsurface sources when infiltration increased.

  1. Chemical pollution in the Arctic and Sub-Arctic marine ecosystems: an overview of current knowledge

    Energy Technology Data Exchange (ETDEWEB)

    Savinova, T.N.; Gabrielsen, G.W.; Falk-Petersen, S.

    1995-02-01

    This report is part of a research project in the framework of the Norwegian-Russian Environmental Cooperation, which was initiated in 1991 to elucidate the present status of environmental contaminants in the highly sensitive Arctic aquatic ecosystem, with special focus on sea birds. Although these ecosystems are the least polluted areas in the world, they are contaminated. The main pathways of contamination into Arctic and sub-Arctic marine ecosystems are atmospheric transport, ocean currents and rivers and in some areas, dumping and ship accidents. A literature survey reveals: (1) there is a lack of data from several trophic levels, (2) previous data are difficult to compare with recent data because of increased quality requirement, (3) not much has been done to investigate the effects of contaminants on the cellular level, at individual or population levels. 389 refs., 7 figs., 32 tabs.

  2. Nonvascular contribution to ecosystem NPP in a subarctic heath during early and late growing season

    DEFF Research Database (Denmark)

    Campioli, Matteo; Samson, Roeland; Michelsen, Anders

    2009-01-01

    Bryophytes and lichens abound in many arctic ecosystems and can contribute substantially to the ecosystem net primary production (NPP). Because of their growth seasonality and their potential for growth out of the growing season peak, bryophyte and lichen contribution to NPP may be particularly...... significant when vascular plants are less active and ecosystems act as a source of carbon (C). To clarify these dynamics, nonvascular and vascular aboveground NPP was compared for a subarctic heath during two contrasting periods of the growing season, viz. early-mid summer and late summer-early autumn....... Nonvascular NPP was determined by assessing shoot biomass increment of three moss species (Hylocomium splendens, Pleurozium schreberi and Dicranum elongatum) and by scaling to ecosystem level using average standing crop. For D. elongatum, these estimates were compared with production estimates obtained from...

  3. Phenological responses of Icelandic subarctic grasslands to short-term and long-term natural soil warming.

    Science.gov (United States)

    Leblans, Niki I W; Sigurdsson, Bjarni D; Vicca, Sara; Fu, Yongshuo; Penuelas, Josep; Janssens, Ivan A

    2017-11-01

    The phenology of vegetation, particularly the length of the growing season (LOS; i.e., the period from greenup to senescence), is highly sensitive to climate change, which could imply potent feedbacks to the climate system, for example, by altering the ecosystem carbon (C) balance. In recent decades, the largest extensions of LOS have been reported at high northern latitudes, but further warming-induced LOS extensions may be constrained by too short photoperiod or unfulfilled chilling requirements. Here, we studied subarctic grasslands, which cover a vast area and contain large C stocks, but for which LOS changes under further warming are highly uncertain. We measured LOS extensions of Icelandic subarctic grasslands along natural geothermal soil warming gradients of different age (short term, where the measurements started after 5 years of warming and long term, i.e., warmed since ≥50 years) using ground-level measurements of normalized difference vegetation index. We found that LOS linearly extended with on average 2.1 days per °C soil warming up to the highest soil warming levels (ca. +10°C) and that LOS had the potential to extend at least 1 month. This indicates that the warming impact on LOS in these subarctic grasslands will likely not saturate in the near future. A similar response to short- and long-term warming indicated a strong physiological control of the phenological response of the subarctic grasslands to warming and suggested that genetic adaptations and community changes were likely of minor importance. We conclude that the warming-driven extension of the LOSs of these subarctic grasslands did not saturate up to +10°C warming, and hence that growing seasons of high-latitude grasslands are likely to continue lengthening with future warming (unless genetic adaptations or species shifts do occur). This persistence of the warming-induced extension of LOS has important implications for the C-sink potential of subarctic grasslands under climate

  4. A systems approach to understanding subarctic critical zone changes in a warming climate (Invited)

    Science.gov (United States)

    Rich, V. I.; McCalley, C. K.; Woodcroft, B. J.; Kim, E.; Hodgkins, S. B.; Tfaily, M. M.; Wehr, R. A.; Logan, T.; Jones, R.; Mondav, R.; Hurst, G.; Verberkmoes, N.; Li, C.; Frolking, S. E.; Crill, P. M.; Chanton, J.; Saleska, S. R.; Tyson, G. W.

    2013-12-01

    Climate change is dramatically altering the subarctic and Arctic Critical Zone. Permafrost, which currently holds approximately one third of global soil carbon in a relatively unavailable form, is predicted to be virtually eliminated by the end of the century. One endpoint for permafrost habitat thaw is wetlands, which are a major source of the microbially-produced greenhouse gas methane. This creates a potentially large positive feedback to climate change. Our team is using a systems approach spanning diverse geochemical (high-resolution greenhouse gas isofluxes and soil/peat geochemistry) and molecular (16S rRNA gene amplicon, metagenomic and metaproteomic sequencing) measurements to track parallel changes in carbon cycling and in situ microbiology across a natural permafrost thaw gradient. Thaw at this site results in a three-stage habitat shift from ericaceous shrubs, to peat moss, to sedges, concomitant with a substantial increase in methane emissions. Isotopically, emitted methane shifts along the thaw gradient away from hydrogenotrophic methane production, in parallel with the appearance of acetoclastic methanogens in the microbial community. Community data have also revealed the presence of a novel, highly-active methanogen from the euryarchaeal lineage Rice Cluster-II, dubbed Candidatus Methanoflorens stordalenmirensis. Its ';species' is present in numerous other global wetland datasets, has the genomic capacity (inferred from its population genome) for hydrogenotrophic methanogenesis, and was the highest environmental correlate of emitted methane's isotopic signature. In situ community global protein expression profiles (i.e. metaproteomes) revealed that it strongly expresses its hydrogentrophic methanogensis genes, and that methanogenesis is a dominant signal in the overall community proteome. As we generate a portrait of how thaw impacts this major subarctic critical zone habitat, we are working with ecosystem process modelers to integrate new

  5. Functional Redundancy Facilitates Resilience of Subarctic Phytoplankton Assemblages toward Ocean Acidification and High Irradiance

    Directory of Open Access Journals (Sweden)

    Clara J. M. Hoppe

    2017-07-01

    Full Text Available In order to understand how ocean acidification (OA and enhanced irradiance levels might alter phytoplankton eco-physiology, productivity and species composition, we conducted an incubation experiment with a natural plankton assemblage from sub-surface Subarctic waters (Davis Strait, 63°N. The phytoplankton assemblage was exposed to 380 and 1,000 μatm pCO2 at both 15 and 35% surface irradiance over 2 weeks. The incubations were monitored and characterized in terms of their photo-physiology, biomass stoichiometry, primary production and dominant phytoplankton species. We found that the phytoplankton assemblage exhibited pronounced high-light stress in the first days of the experiment (20–30% reduction in photosynthetic efficiency, Fv/Fm. This stress signal was more pronounced when grown under OA and high light, indicating interactive effects of these environmental variables. Primary production in the high light treatments was reduced by 20% under OA compared to ambient pCO2 levels. Over the course of the experiment, the assemblage fully acclimated to the applied treatments, achieving similar bulk characteristics (e.g., net primary production and elemental stoichiometry under all conditions. We did, however, observe a pCO2-dependent shift in the dominant diatom species, with Pseudonitzschia sp. dominating under low and Fragilariopsis sp. under high pCO2 levels. Our results indicate an unexpectedly high level of resilience of Subarctic phytoplankton to OA and enhanced irradiance levels. The co-occurring shift in dominant species suggests functional redundancy to be an important, but so-far largely overlooked mechanism for resilience toward climate change.

  6. Utilization of iron bound to strong organic ligands by plankton communities in the subarctic Pacific Ocean

    Science.gov (United States)

    Maldonado, Maria T.; Price, Neil M.

    1999-11-01

    Experiments were conducted along a coastal-oceanic transect in the NE subarctic Pacific to examine acquisition of organically complexed Fe by autotrophic and heterotrophic plankton. During short-term experiments, plankton took up Fe bound to the siderophores desferrioxamine B and E, microbial Fe chelates with a high affinity for Fe. Uptake occurred in all size fractions: 0.2-1, 1-3, and >3 μm. Heterotrophic bacteria had higher Fe : C ratios (1.5 to 2 times) than phytoplankton, and accounted for 70±8% of the total Fe uptake by the community (mol Fe ml -1 h -1). This latter result was partially explained by the higher C biomass of bacteria, but was not related to their productivity. Carbon-specific uptake rates of Fe were also faster (1.6±1.5 times) in bacteria than phytoplankton. When the rates were normalized per cell surface area, however, phytoplankton were observed to transport Fe at a rate more than 30 times that of bacteria. Large phytoplankton greater than 3 μm reduced Fe bound to organic ligands extracellularly. Their Fe : C ratios and rates of uptake and reduction of organically bound Fe were very similar at all stations along the transect and were characteristic of Fe-stressed phytoplankton. A strong seasonal trend of Fe uptake and reduction was apparent. The results suggest that heterotrophic bacteria are responsible for a large fraction of dissolved Fe uptake and that the indigenous plankton of the subarctic Pacific are able to acquire Fe bound to strong organic ligands, the predominant form of dissolved Fe in the sea.

  7. The transformation and fate of sub-Arctic microphytobenthos carbon revealed through 13C-labeling

    DEFF Research Database (Denmark)

    Oakes, Joanne M.; Rysgaard, Søren; Glud, Ronnie N.

    2016-01-01

    Cm(-2)h(-1)) was comparable to that reported for temperate regions. Some of the C-13 fixed by sub-Arctic MPB was rapidly (within 0.5 d) transferred to deeper sediments (below 2 cm), but most was retained within surface sediments (>70.2% of the C-13 present at any time during the study). At any time, MPB...... accounted for49.8% of this C-13. The C-13 content of sediment organic carbon declined over time, but>31% of the C-13 fixed within the first tidal cycle remained after 31 d, suggesting that sub-Arctic MPB may contribute to coastal carbon retention during the productive season. Over 21 d, 10.6% of the fixed C...... conditions are more important than climate differences for determining the processing and fate of MPB-C....

  8. Analysis of the boreal forest-tundra ecotone: A test of AVIRIS capabilities in the Eastern Canadian subarctic

    Science.gov (United States)

    Goward, Samuel N.; Petzold, Donald E.

    1989-01-01

    A comparison was conducted between ground reflectance spectra collected in Schefferville, Canada and imaging spectrometer observations acquired by the AVIRIS sensor in a flight of the ER-2 Aircraft over the same region. The high spectral contrasts present in the Canadian Subarctic appeared to provide an effective test of the operational readiness of the AVIRIS sensor. Previous studies show that in this location various land cover materials possess a wide variety of visible/near infrared reflectance properties. Thus, this landscape served as an excellent test for the sensing variabilities of the newly developed AVIRIS sensor. An underlying hypothesis was that the unique visible/near infrared spectral reflectance patterns of Subarctic lichens could be detected from high altitudes by this advanced imaging spectrometer. The relation between lichen occurrence and boreal forest-tundra ecotone dynamics was investigated.

  9. Atmospheric controls on methane emissions from a subarctic bog in northern Quebec, Canada, using an open-path eddy covariance system

    Science.gov (United States)

    Rousseau, A. N.; Nadeau, D. F.; Parlange, M. B.; Coursolle, C.; Margolis, H. A.

    2012-12-01

    Wetlands are the largest natural source of atmospheric methane, a powerful greenhouse gas. Over such environments, methane fluxes are traditionally quantified with static or dynamic chambers and gas chromatography. Although inexpensive and portable, this method does not allow for continuous measurements besides not capturing the effect of atmospheric turbulence on methane emissions. An alternative is closed-path eddy covariance systems, but these usually require high power consumption and regular maintenance, both of which are difficult to supply in highly remote areas where most Canadian wetlands are found. In this study we deployed the new open-path methane analyzer (model Li-7700) from Li-Cor inc. along with surface energy budget sensors over a 60-ha subarctic bog from June to September 2012. The field site (53.7°N, 78.2°W) is located near James Bay within the La Grande Rivière watershed. This work discusses the presence of diurnal patterns in turbulent methane fluxes, and analyzes the effect of atmospheric stability, turbulence intensity and other atmospheric controls on fluxes magnitude and timing. Methane emissions are also quantified at the daily scale and compared to previously reported values over similar sites with other methods. A more technical discussion is also included in which advantages, drawbacks and optimal setup configuration of the instrument are presented.

  10. Potential macro-detritivore range expansion into the subarctic stimulates litter decomposition: a new positive feedback mechanism to climate change?

    Science.gov (United States)

    van Geffen, Koert G; Berg, Matty P; Aerts, Rien

    2011-12-01

    As a result of low decomposition rates, high-latitude ecosystems store large amounts of carbon. Litter decomposition in these ecosystems is constrained by harsh abiotic conditions, but also by the absence of macro-detritivores. We have studied the potential effects of their climate change-driven northward range expansion on the decomposition of two contrasting subarctic litter types. Litter of Alnus incana and Betula pubescens was incubated in microcosms together with monocultures and all possible combinations of three functionally different macro-detritivores (the earthworm Lumbricus rubellus, isopod Oniscus asellus, and millipede Julus scandinavius). Our results show that these macro-detritivores stimulated decomposition, especially of the high-quality A. incana litter and that the macro-detritivores tested differed in their decomposition-stimulating effects, with earthworms having the largest influence. Decomposition processes increased with increasing number of macro-detritivore species, and positive net diveristy effects occurred in several macro-detritivore treatments. However, after correction for macro-detritivore biomass, all interspecific differences in macro-detritivore effects, as well as the positive effects of species number on subarctic litter decomposition disappeared. The net diversity effects also appeared to be driven by variation in biomass, with a possible exception of net diversity effects in mass loss. Based on these results, we conclude that the expected climate change-induced range expansion of macro-detritivores into subarctic regions is likely to result in accelerated decomposition rates. Our results also indicate that the magnitude of macro-detritivore effects on subarctic decomposition will mainly depend on macro-detritivore biomass, rather than on macro-detritivore species number or identity.

  11. Potential macro-detritivore range expansion into the subarctic stimulates litter decomposition: a new positive feedback mechanism to climate change?

    OpenAIRE

    Geffen, van, LCMM; Berg, M.P.; Aerts, R.

    2011-01-01

    As a result of low decomposition rates, high-latitude ecosystems store large amounts of carbon. Litter decomposition in these ecosystems is constrained by harsh abiotic conditions, but also by the absence of macro-detritivores. We have studied the potential effects of their climate change-driven northward range expansion on the decomposition of two contrasting subarctic litter types. Litter of Alnus incana and Betula pubescens was incubated in microcosms together with monocultures and all pos...

  12. Changing times, changing stories: Generational differences in climate change perspectives from four remote indigenous communities in Subarctic Alaska

    Science.gov (United States)

    Herman-Mercer, Nicole M.; Matkin, Elli; Laituri, Melinda J.; Toohey, Ryan C; Massey, Maggie; Kelly Elder,; Schuster, Paul F.; Mutter, Edda A.

    2016-01-01

    Indigenous Arctic and Subarctic communities currently are facing a myriad of social and environmental changes. In response to these changes, studies concerning indigenous knowledge (IK) and climate change vulnerability, resiliency, and adaptation have increased dramatically in recent years. Risks to lives and livelihoods are often the focus of adaptation research; however, the cultural dimensions of climate change are equally important because cultural dimensions inform perceptions of risk. Furthermore, many Arctic and Subarctic IK climate change studies document observations of change and knowledge of the elders and older generations in a community, but few include the perspectives of the younger population. These observations by elders and older generations form a historical baseline record of weather and climate observations in these regions. However, many indigenous Arctic and Subarctic communities are composed of primarily younger residents. We focused on the differences in the cultural dimensions of climate change found between young adults and elders. We outlined the findings from interviews conducted in four indigenous communities in Subarctic Alaska. The findings revealed that (1) intergenerational observations of change were common among interview participants in all four communities, (2) older generations observed more overall change than younger generations interviewed by us, and (3) how change was perceived varied between generations. We defined “observations” as the specific examples of environmental and weather change that were described, whereas “perceptions” referred to the manner in which these observations of change were understood and contextualized by the interview participants. Understanding the differences in generational observations and perceptions of change are key issues in the development of climate change adaptation strategies.

  13. Changing times, changing stories: generational differences in climate change perspectives from four remote indigenous communities in Subarctic Alaska

    Directory of Open Access Journals (Sweden)

    Nicole M. Herman-Mercer

    2016-09-01

    Full Text Available Indigenous Arctic and Subarctic communities currently are facing a myriad of social and environmental changes. In response to these changes, studies concerning indigenous knowledge (IK and climate change vulnerability, resiliency, and adaptation have increased dramatically in recent years. Risks to lives and livelihoods are often the focus of adaptation research; however, the cultural dimensions of climate change are equally important because cultural dimensions inform perceptions of risk. Furthermore, many Arctic and Subarctic IK climate change studies document observations of change and knowledge of the elders and older generations in a community, but few include the perspectives of the younger population. These observations by elders and older generations form a historical baseline record of weather and climate observations in these regions. However, many indigenous Arctic and Subarctic communities are composed of primarily younger residents. We focused on the differences in the cultural dimensions of climate change found between young adults and elders. We outlined the findings from interviews conducted in four indigenous communities in Subarctic Alaska. The findings revealed that (1 intergenerational observations of change were common among interview participants in all four communities, (2 older generations observed more overall change than younger generations interviewed by us, and (3 how change was perceived varied between generations. We defined "observations" as the specific examples of environmental and weather change that were described, whereas "perceptions" referred to the manner in which these observations of change were understood and contextualized by the interview participants. Understanding the differences in generational observations and perceptions of change are key issues in the development of climate change adaptation strategies.

  14. Relationships between ecosystem metabolism, benthic macroinvertebrate densities, and environmental variables in a sub-arctic Alaskan river

    Science.gov (United States)

    Benson, Emily R.; Wipfli, Mark S.; Clapcott, Joanne E.; Hughes, Nicholas F.

    2013-01-01

    Relationships between environmental variables, ecosystem metabolism, and benthos are not well understood in sub-arctic ecosystems. The goal of this study was to investigate environmental drivers of river ecosystem metabolism and macroinvertebrate density in a sub-arctic river. We estimated primary production and respiration rates, sampled benthic macroinvertebrates, and monitored light intensity, discharge rate, and nutrient concentrations in the Chena River, interior Alaska, over two summers. We employed Random Forests models to identify predictor variables for metabolism rates and benthic macroinvertebrate density and biomass, and calculated Spearman correlations between in-stream nutrient levels and metabolism rates. Models indicated that discharge and length of time between high water events were the most important factors measured for predicting metabolism rates. Discharge was the most important variable for predicting benthic macroinvertebrate density and biomass. Primary production rate peaked at intermediate discharge, respiration rate was lowest at the greatest time since last high water event, and benthic macroinvertebrate density was lowest at high discharge rates. The ratio of dissolved inorganic nitrogen to soluble reactive phosphorus ranged from 27:1 to 172:1. We found that discharge plays a key role in regulating stream ecosystem metabolism, but that low phosphorous levels also likely limit primary production in this sub-arctic stream.

  15. Export production in the subarctic North Pacific over the last 800 kyrs: No evidence for iron fertilization?

    Science.gov (United States)

    Kienast, S.S.; Hendy, I.L.; Crusius, J.; Pedersen, Thomas F.; Calvert, S.E.

    2004-01-01

    The subarctic North Pacific is a high nitrate-low chlorophyll (HNLC) region, where phytoplankton growth rates, especially those of diatoms, are enhanced when micro-nutrient Fe is added. Accordingly, it has been suggested that glacial Fe-laden dust might have increased primary production in this region. This paper reviews published palaeoceanographic records of export production over the last 800 kyrs from the open North Pacific (north of ???35??N). We find different patterns of export production change over time in the various domains of the North Pacific (NW and NE subarctic gyres, the marginal seas and the transition zone). However, there is no compelling evidence for an overall increase in productivity during glacials in the subarctic region, challenging the paradigm that dust-born Fe fertilization of this region has contributed to the glacial draw down of atmospheric CO2. Potential reasons for the lack of increased glacial export production include the possibility that Fe-fertilization rapidly drives the ecosystem towards limitation by another nutrient. This effect would have been exacerbated by an even more stable mixed layer compared to today. ?? The Oceanographic Society of Japan.

  16. Expectancy Theory as a Predictor of Grade-Point Averages, Satisfaction, and Participation in the College Environment. ASHE 1983 Annual Meeting Paper.

    Science.gov (United States)

    Lincoln, Yvonna S.; And Others

    The ability of Vroom's expectancy motivation theory to predict student satisfaction with the college environment, student participation at school, and student academic performance was studied. Specific objectives of the study were as follows: to test the ability of Vroom's valence model to predict student satisfaction, to test the ability of…

  17. 6. annual report, research programme ``Environment and health``. Conference programme and abstracts; 6. Statuskolloquium des Projektes Umwelt und Gesundheit (PUG). Programm und Kurzfassung der Vortraege

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The document contains the abstracts of papers and the contributions to the discussion forums of the 6th status colloquium of the ``Environment and Health`` project, held on 3. and 4. March 1997 at Karlsruhe Research Center, Fortbildungszentrum fuer Technik und Umwelt. The session subjects are: Air pollution and respiratory system diseases (LUVA session); Diseases caused by anthropogenic trace substances in the environment (UTOX session); Food-induced allergies and intolerance phenomena (PAUL session). (VHE) [Deutsch] Im vorliegenden Band werden die Abstracts der Vortraege und der Beitraege der Diskussionskreise des 6. Statuskolloquiums des Projektes `Umwelt und Gesundheit` im Fortbildungszentrum fuer Technik und Umwelt des Forschungszentrums Karlsruhe vom 03. und 04.03.1997 vorgestellt. Themen waren `Luftverunreinigungen und Atemwegserkrankungen` (LUVA), `Erkrankungen durch zivilisationsbedingte Spurenstoffe in der Umwelt` (UTOX) sowie `Allergien und Unvertraeglichkeitsreaktionen durch Lebensmittel` (PAUL). (VHE)

  18. Reproductive allocation and output in herbaceous annuals of the genera Polygonum, Ipomoea, and Cassia in elevated CO[sub 2] environments

    Energy Technology Data Exchange (ETDEWEB)

    Farnsworth, E.J.; Bazzaz, F.A. (Harvard Univ., Cambridge, MA (United States))

    1994-06-01

    In assessing the capacity of plants to adapt to rapidly changing global climate, we must elucidate the impacts of elevated carbon dioxide on reproduction, fitness and evolution. We investigated how elevated CO[sub 2] influenced reproduction and growth of plants exhibiting a range of floral displays, the implications of shifts in allocation for fitness in these species, and whether related taxa would show similar patterns of response. Three herbaceous, annual species each of the genera Polygonum, Ipomoea, and Cassia were grown under 350 or 700 ppm CO[sub 2]. Vegetative growth and reproductive output were non-destructively measured throughout the full life span, and biomass calibrated with a subsample harvest at first flowering. Viability and germination studies of seed progeny were conducted to more precisely characterize fitness. Timecourse and numbers of floral buds, flowers, unripe and abscised fruits differed between CO[sub 2] treatments. Genera differed significantly in their phenological responses to elevated CO[sub 2], Polygonum and Cassia species (but not Ipomoea) showed accelerated, enhanced reproduction. Elevated CO[sub 2] ameliorated trade-offs between vegetative and floral production. However, seed [open quotes]quality[close quotes] and fitness were not always directly correlated with quantity produced. Species within general responded more consistently to CO[sub 2], indicating that phylogeny and life form may be general predictors of performance under global change.

  19. Association of climatic factors with infectious diseases in the Arctic and subarctic region – a systematic review

    Directory of Open Access Journals (Sweden)

    Christina Hedlund

    2014-07-01

    Full Text Available Background: The Arctic and subarctic area are likely to be highly affected by climate change, with possible impacts on human health due to effects on food security and infectious diseases. Objectives: To investigate the evidence for an association between climatic factors and infectious diseases, and to identify the most climate-sensitive diseases and vulnerable populations in the Arctic and subarctic region. Methods: A systematic review was conducted. A search was made in PubMed, with the last update in May 2013. Inclusion criteria included human cases of infectious disease as outcome, climate or weather factor as exposure, and Arctic or subarctic areas as study origin. Narrative reviews, case reports, and projection studies were excluded. Abstracts and selected full texts were read and evaluated by two independent readers. A data collection sheet and an adjusted version of the SIGN methodology checklist were used to assess the quality grade of each article. Results: In total, 1953 abstracts were initially found, of which finally 29 articles were included. Almost half of the studies were carried out in Canada (n=14, the rest from Sweden (n=6, Finland (n=4, Norway (n=2, Russia (n=2, and Alaska, US (n=1. Articles were analyzed by disease group: food- and waterborne diseases, vector-borne diseases, airborne viral- and airborne bacterial diseases. Strong evidence was found in our review for an association between climatic factors and food- and waterborne diseases. The scientific evidence for a link between climate and specific vector- and rodent-borne diseases was weak due to that only a few diseases being addressed in more than one publication, although several articles were of very high quality. Air temperature and humidity seem to be important climatic factors to investigate further for viral- and bacterial airborne diseases, but from our results no conclusion about a causal relationship could be drawn. Conclusions: More studies of high quality

  20. Fine-scale spatial and interannual cadmium isotope variability in the subarctic northeast Pacific

    Science.gov (United States)

    Janssen, D. J.; Abouchami, W.; Galer, S. J. G.; Cullen, J. T.

    2017-08-01

    We present dissolved cadmium (Cd) concentrations, [Cd], and stable isotope compositions, ε 112 / 110Cd, in high-resolution depth profiles from five stations along the Line P transect in the subarctic northeast Pacific Ocean. In addition to profiles collected in 2012, subsurface isopycnal samples and surface samples were collected in 2013 and 2014 respectively, providing both temporal and spatial coverage. Surface waters are characterized by Cd depletion relative to phosphate (4 3-PO) compared to deepwater 4 -3Cd:PO, and high inferred remineralization ratios in the nutricline (0.45nmolμmol-1) are observed, consistent with Cd enrichment relative to phosphorus (P) in surface-derived biogenic particles. The correlation between Cd and 4 3-PO weakens at depths where oxygen is highly depleted as shown by local minima in dissolved [Cd] and the tracer Cd*. The decoupling, which is driven by a deficit of Cd relative to 4 3-PO, appears consistent with the recent hypothesis of dissolved Cd removal in oxygen-depleted regions by insoluble metal sulfide formation. Dissolved ε 112 / 110Cd indicates a biologically driven fractionation in surface waters with more positive (heavy) values in the upper water column and lower (light) values in deeper waters. The highest ε 112 / 110Cd observed in our sample set (5.19 ± 0.23) is comparable to observations from the Southern Ocean but is significantly lighter than maximum reported surface values from the subtropical North Pacific of ε 112 / 110Cd ≥ 15. A global compilation of low [Cd] surface water shows similar differences in maximum ε 112 / 110Cd. A surface water intercalibration should be prioritized to help determine if these differences at low [Cd] reflect true physical or biological variability or are due to analytical artefacts. Surface samples from the 2012 sampling campaign fit a closed-system Rayleigh fractionation model; however, surface waters sampled in 2014 had much lower [Cd] with relatively constant ε 112 / 110Cd

  1. Tulane/Xavier University hazardous materials in aquatic environments of the Mississippi River Basin. Annual technical report, January 1--December 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-05-02

    Tulane and Xavier Universities have singled out the environment as a major strategic focus for research and training for now and beyond the year 2000. In 1989, the Tulane/Xavier Center for Bioenvironmental Research (CBR) was established as the umbrella organization which coordinates environmental research at both universities. In December, 1992, the Tulane/Xavier CBR was awarded a five year grant to study pollution in the Mississippi River system. The Hazardous Materials in Aquatic Environments of the Mississippi River Basin project is a broad research and education program aimed at elucidating the nature and magnitude of toxic materials that contaminate aquatic environments of the Mississippi River Basin. Studies include defining the complex interactions that occur during the transport of contaminants, the actual and potential impact on ecological systems and health, and the mechanisms through which these impacts might be remediated. The Mississippi River Basin represents a model system for analyzing and solving contamination problems that are found in aquatic systems world-wide. Summaries which describe objectives, goals, and accomplishments are included on ten collaborative cluster projects, two education projects, and six initiation projects. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  2. Complex population structure of Lyme borreliosis group spirochete Borrelia garinii in subarctic Eurasia.

    Science.gov (United States)

    Comstedt, Pär; Asokliene, Loreta; Eliasson, Ingvar; Olsen, Björn; Wallensten, Anders; Bunikis, Jonas; Bergström, Sven

    2009-06-09

    Borrelia garinii, a causative agent of Lyme borreliosis in Europe and Asia, is naturally maintained in marine and terrestrial enzootic cycles, which primarily involve birds, including seabirds and migratory passerines. These bird groups associate with, correspondingly, Ixodes uriae and Ixodes ricinus ticks, of which the latter species may bite and transmit the infection to humans. Studies of the overlap between these two natural cycles of B. garinii have been limited, in part due to the absence of representative collections of this spirochete's samples, as well as of the lack of reliable measure of the genetic heterogeneity of its strains. As a prerequisite for understanding the epidemiological correlates of the complex maintenance of B. garinii, the present study sought to assess the diversity and phylogenetic relationships of this species' strains from its natural hosts and patients with Lyme borreliosis from subarctic Eurasia. We used sequence typing of the partial rrs-rrl intergenic spacer (IGS) of archived and prospective samples of B. garinii from I. uriae ticks collected predominantly on Commander Islands in North Pacific, as well as on the islands in northern Sweden and arctic Norway. We also typed B. garinii samples from patients with Lyme borreliosis and I. ricinus ticks infesting migratory birds in southern Sweden, or found questing in selected sites on the islands in the Baltic Sea and Lithuania. Fifty-two (68%) of 77 B. garinii samples representing wide geographical range and associated with I. ricinus and infection of humans contributed 12 (60%) of total 20 identified IGS variants. In contrast, the remaining 25 (32%) samples recovered from I. uriae ticks from a few islands accounted for as many as 10 (50%) IGS types, suggesting greater local diversity of B. garinii maintained by seabirds and their ticks. Two IGS variants of the spirochete in common for both tick species were found in I. ricinus larvae from migratory birds, an indication that B

  3. Complex population structure of Lyme borreliosis group spirochete Borrelia garinii in subarctic Eurasia.

    Directory of Open Access Journals (Sweden)

    Pär Comstedt

    Full Text Available Borrelia garinii, a causative agent of Lyme borreliosis in Europe and Asia, is naturally maintained in marine and terrestrial enzootic cycles, which primarily involve birds, including seabirds and migratory passerines. These bird groups associate with, correspondingly, Ixodes uriae and Ixodes ricinus ticks, of which the latter species may bite and transmit the infection to humans. Studies of the overlap between these two natural cycles of B. garinii have been limited, in part due to the absence of representative collections of this spirochete's samples, as well as of the lack of reliable measure of the genetic heterogeneity of its strains. As a prerequisite for understanding the epidemiological correlates of the complex maintenance of B. garinii, the present study sought to assess the diversity and phylogenetic relationships of this species' strains from its natural hosts and patients with Lyme borreliosis from subarctic Eurasia. We used sequence typing of the partial rrs-rrl intergenic spacer (IGS of archived and prospective samples of B. garinii from I. uriae ticks collected predominantly on Commander Islands in North Pacific, as well as on the islands in northern Sweden and arctic Norway. We also typed B. garinii samples from patients with Lyme borreliosis and I. ricinus ticks infesting migratory birds in southern Sweden, or found questing in selected sites on the islands in the Baltic Sea and Lithuania. Fifty-two (68% of 77 B. garinii samples representing wide geographical range and associated with I. ricinus and infection of humans contributed 12 (60% of total 20 identified IGS variants. In contrast, the remaining 25 (32% samples recovered from I. uriae ticks from a few islands accounted for as many as 10 (50% IGS types, suggesting greater local diversity of B. garinii maintained by seabirds and their ticks. Two IGS variants of the spirochete in common for both tick species were found in I. ricinus larvae from migratory birds, an indication

  4. Annual Interviews

    CERN Multimedia

    Human Resources Department

    2005-01-01

    Annex II, page 1, Section 3 of the Administrative Circular no. 26 (Rev. 5) states that "The annual interview shall usually take place between 15 November of the reference year and 15 February of the following year." Following the meeting of the Executive Board on 7 December 2004 and the meeting of the Standing Concertation Committee on 19 January 2005, it has been decided, for the advancement exercise of 2005, to extend this period until 15 March 2005. Human Resources Department Tel. 73566

  5. Feasibility analysis of a smart grid photovoltaics system for the subarctic rural region in Alaska

    Science.gov (United States)

    Yao, Lei

    A smart grid photovoltaics system was developed to demonstrate that the system is feasible for a similar off-grid rural community in the subarctic region in Alaska. A system generation algorithm and a system business model were developed to determine feasibility. Based on forecasts by the PV F-Chart software, a 70° tilt angle in winter, and a 34° tilt angle in summer were determined to be the best angles for electrical output. The proposed system's electricity unit cost was calculated at 32.3 cents/kWh that is cheaper than current unsubsidized electricity price (46.8 cents/kWh) in off-grid rural communities. Given 46.8 cents/kWh as the electricity unit price, the system provider can break even when 17.3 percent of the total electrical revenue through power generated by the proposed system is charged. Given these results, the system can be economically feasible during the life-cycle period. With further incentives, the system may have a competitive advantage.

  6. Food web topology and parasites in the pelagic zone of a subarctic lake

    Science.gov (United States)

    Amundsen, Per-Arne; Lafferty, K.D.; Knudsen, R.; Primicerio, R.; Klemetsen, A.; Kuris, A.M.

    2009-01-01

    Parasites permeate trophic webs with their often complex life cycles, but few studies have included parasitism in food web analyses. Here we provide a highly resolved food web from the pelagic zone of a subarctic lake and explore how the incorporation of parasites alters the topology of the web. 2. Parasites used hosts at all trophic levels and increased both food-chain lengths and the total number of trophic levels. Their inclusion in the network analyses more than doubled the number of links and resulted in an increase in important food-web characteristics such as linkage density and connectance. 3. More than half of the parasite taxa were trophically transmitted, exploiting hosts at multiple trophic levels and thus increasing the degree of omnivory in the trophic web. 4. For trophically transmitted parasites, the number of parasite-host links exhibited a positive correlation with the linkage density of the host species, whereas no such relationship was seen for nontrophically transmitted parasites. Our findings suggest that the linkage density of free-living species affects their exposure to trophically transmitted parasites, which may be more likely to adopt highly connected species as hosts during the evolution of complex life cycles. 5. The study supports a prominent role for parasites in ecological networks and demonstrates that their incorporation may substantially alter considerations of food-web structure and functioning. ?? 2009 British Ecological Society.

  7. Impact of early and late winter icing events on sub-arctic dwarf shrubs.

    Science.gov (United States)

    Preece, C; Phoenix, G K

    2014-01-01

    Polar regions are predicted to undergo large increases in winter temperature and an increased frequency of freeze-thaw cycles, which can cause ice layers in the snow pack and ice encasement of vegetation. Early or late winter timing of ice encasement could, however, modify the extent of damage caused to plants. To determine impacts of the date of ice encasement, a novel field experiment was established in sub-arctic Sweden, with icing events simulated in January and March 2008 and 2009. In the subsequent summers, reproduction, phenology, growth and mortality, as well as physiological indicators of leaf damage were measured in the three dominant dwarf shrubs: Vaccinium uliginosum, Vaccinium vitis-idaea and Empetrum nigrum. It was hypothesised that January icing would be more damaging compared to March icing due to the longer duration of ice encasement. Following 2 years of icing, E. nigrum berry production was 83% lower in January-iced plots compared to controls, and V. vitis-idaea electrolyte leakage was increased by 69%. Conversely, electrolyte leakage of E. nigrum was 25% lower and leaf emergence of V. vitis-idaea commenced 11 days earlier in March-iced plots compared to control plots in 2009. There was no effect of icing on any of the other parameters measured, indicating that overall these study species have moderate to high tolerance to ice encasement. Even much longer exposure under the January icing treatment does not clearly increase damage. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.

  8. Paleoclimatic significance of chemical weathering in loess-derived paleosols of subarctic central Alaska

    Science.gov (United States)

    Muhs, D.R.; Ager, T.A.; Skipp, G.; Beann, J.; Budahn, J.; McGeehin, J.P.

    2008-01-01

    Chemical weathering in soils has not been studied extensively in high-latitude regions. Loess sequences with modern soils and paleosols are present in much of subarctic Alaska, and allow an assessment of present and past chemical weathering. Five sections were studied in detail in the Fairbanks, Alaska, area. Paleosols likely date to mid-Pleistocene interglacials, the last interglacial, and early-to-mid-Wisconsin interstadiale. Ratios of mobile (Na, Ca, Mg, Si) to immobile (Ti or Zr) elements indicate that modern soils and most interstadial and interglacial paleosols are characterized by significant chemical weathering. Na2O/TiO2 is lower in modern soils and most paleosols compared to parent loess, indicating depletion of plagioclase. In the clay fraction, smectite is present in Tanana and Yukon River source sediments, but is absent or poorly expressed in modern soils and paleosols, indicating depletion of this mineral also. Loss of both plagioclase and smectite is well expressed in soils and paleosols as lower SiO 2/TiO2. Carbonates are present in the river source sediments, but based on CaO/TiO2, they are depleted in soils and most paleosols (with one exception in the early-to-mid-Wisconsin period). Thus, most soil-forming intervals during past interglacial and interstadial periods in Alaska had climatic regimes that were at least as favorable to mineral weathering as today, and suggest boreal forest or acidic tundra vegetation. ?? 2008 Regents of the University of Colorado.

  9. The relative contributions of biological and abiotic processes to carbon dynamics in subarctic sea ice

    DEFF Research Database (Denmark)

    Søgaard, Dorte Haubjerg; Thomas, David N.; Rysgaard, Søren

    2013-01-01

    Knowledge on the relative effects of biological activity and precipitation/dissolution of calcium carbonate (CaCO3) in influencing the air-ice CO2 exchange in sea-ice-covered season is currently lacking. Furthermore, the spatial and temporal occurrence of CaCO3 and other biogeochemical parameters...... in sea ice are still not well described. Here we investigated autotrophic and heterotrophic activity as well as the precipitation/dissolution of CaCO3 in subarctic sea ice in South West Greenland. Integrated over the entire ice season (71 days), the sea ice was net autotrophic with a net carbon fixation...... of 56 mg C m(-2), derived from a sea-ice-related gross primary production of 153 mg C m(-2) and a bacterial carbon demand of 97 mg C m(-2). Primary production contributed only marginally to the TCO2 depletion of the sea ice (7-25 %), which was mainly controlled by physical export by brine drainage...

  10. The Recovery of Two Polluted Subarctic Lakes—Towards Nutrient Management or a Pristine State?

    Directory of Open Access Journals (Sweden)

    Erik Grönlund

    2012-10-01

    Full Text Available Two small subarctic lakes were eutrophicated due to wastewater discharge from 1964. In 1975, a wastewater treatment plant was built and a recovery process started. This paper will: (1 compile the 1972–1974, 1978–1980 and 1985–1988 investigation data regarding phosphorous and microalgae for one of the lakes; (2 complement with unpublished data from 1985 and 2003; and (3 introduce a discussion regarding three alternatives for future development of the lakes in their last phase of recovery. In the latest investigation, 2003, the lakes were assessed as almost recovered. They had returned to an oligotrophic state, but not fully to a pre-sewage situation. In the upper lake, more heavily polluted, the total phosphorous levels had decreased from an average of 168 µg P/L in 1972–1974 to an average of 12 µg P/L in 2003. The phytoplankton biomass had decreased twentyfold during the same period, from 11.2 mg/L to 0.6 mg/L. The Secchi depth had increased from 1.3 m to 2.8 m. The low oxygen level in late winter was still not recovered, thereby profoundly affecting residential organisms in the lakes. The low winter oxygen is assumed to remain so for a long time due to phosphorus release from sediments in the lakes.

  11. Multi-trophic level response to extreme metal contamination from gold mining in a subarctic lake.

    Science.gov (United States)

    Thienpont, Joshua R; Korosi, Jennifer B; Hargan, Kathryn E; Williams, Trisha; Eickmeyer, David C; Kimpe, Linda E; Palmer, Michael J; Smol, John P; Blais, Jules M

    2016-08-17

    Giant Mine, located in the city of Yellowknife (Northwest Territories, Canada), is a dramatic example of subarctic legacy contamination from mining activities, with remediation costs projected to exceed $1 billion. Operational between 1948 and 2004, gold extraction at Giant Mine released large quantities of arsenic and metals from the roasting of arsenopyrite ore. We examined the long-term ecological effects of roaster emissions on Pocket Lake, a small lake at the edge of the Giant Mine lease boundary, using a spectrum of palaeoenvironmental approaches. A dated sedimentary profile tracked striking increases (approx. 1700%) in arsenic concentrations coeval with the initiation of Giant Mine operations. Large increases in mercury, antimony and lead also occurred. Synchronous changes in biological indicator assemblages from multiple aquatic trophic levels, in both benthic and pelagic habitats, indicate dramatic ecological responses to extreme metal(loid) contamination. At the peak of contamination, all Cladocera, a keystone group of primary consumers, as well as all planktonic diatoms, were functionally lost from the sediment record. No biological recovery has been inferred, despite the fact that the bulk of metal(loid) emissions occurred more than 50 years ago, and the cessation of all ore-roasting activities in Yellowknife in 1999. © 2016 The Author(s).

  12. Spatial distribution of aquatic marine fungi across the western Arctic and sub-arctic.

    Science.gov (United States)

    Hassett, Brandon T; Ducluzeau, Anne-Lise L; Collins, Roy E; Gradinger, Rolf

    2017-02-01

    Fungi are important parasites of primary producers and nutrient cyclers in aquatic ecosystems. In the Pacific-Arctic domain, fungal parasitism is linked to light intensities and algal stress that can elevate disease incidence on algae and reduce diatom concentrations. Fungi are vastly understudied in the marine realm and knowledge of their function is constrained by the current understanding of fungal distribution and drivers on global scales. To investigate the spatial distribution of fungi in the western Arctic and sub-Arctic, we used high throughput methods to sequence 18S rRNA, cloned and sequenced 28S rRNA and microscopically counted chytrid-infected diatoms. We identified a broad distribution of fungal taxa predominated by Chytridiomycota and Dikarya. Phylogenetic analysis of our Chytridiomycota clones placed Arctic marine fungi sister to the order Lobulomycetales. This clade of fungi predominated in fungal communities under ice with low snowpack. Microscopic examination of fixed seawater and sea ice samples revealed chytrids parasitizing diatoms collected across the Arctic that notably infected 25% of a single diatom species in the Bering Sea. The Pezizomycotina comprised > 95% of eukaryotic sequence reads in Greenland, providing preliminary evidence for osmotrophs being a substitute for algae as the base of food webs. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

  13. UAV Remote Sensing Surveillance of a Mine Tailings Impoundment in Sub-Arctic Conditions

    Directory of Open Access Journals (Sweden)

    Anssi Rauhala

    2017-12-01

    Full Text Available Mining typically involves extensive areas where environmental monitoring is spatially sporadic. New remote sensing techniques and platforms such as Structure from Motion (SfM and unmanned aerial vehicles (UAVs may offer one solution for more comprehensive and spatially continuous measurements. We conducted UAV campaigns in three consecutive summers (2015–2017 at a sub-Arctic mining site where production was temporarily suspended. The aim was to monitor a 0.5 km2 tailings impoundment and measure potential subsidence of tailings. SfM photogrammetry was used to produce yearly topographical models of the tailings surface, which allowed the amount of surface displacement between years to be tracked. Ground checkpoints surveyed in stable areas of the impoundment were utilized in assessing the vertical accuracy of the models. Observed surface displacements were linked to a combination of erosion, tailings settlement, and possible compaction of the peat layer underlying the tailings. The accuracy obtained indicated that UAV-assisted monitoring of tailings impoundments is sufficiently accurate for supporting impoundment management operations and for tracking surface displacements in the decimeter range.

  14. Residency times and patterns of movement of postbreeding dunlin on a subarctic staging area in Alaska

    Science.gov (United States)

    Warnock, Nils; Handel, Colleen M.; Gill, Robert E.; McCaffery, Brian J.

    2013-01-01

    Understanding how individuals use key resources is critical for effective conservation of a population. The Yukon-Kuskokwim Delta (YKD) in western Alaska is the most important postbreeding staging area for shorebirds in the subarctic North Pacific, yet little is known about movements of shorebirds there during the postbreeding period. To address this information gap, we studied residency times and patterns of movement of 17 adult and 17 juvenile radio-marked Dunlin (Calidris alpina) on the YKD between early August and early October 2005. Throughout this postbreeding period, during which Dunlin were molting, most birds were relocated within a 130 km radius of their capture site on the YKD, but three birds were relocated more than 600 km to the south at estuaries along the Alaska Peninsula. On average, juvenile Dunlin were relocated farther away from the banding site (median relocation distance = 36.3 km) than adult Dunlin (median relocation distance = 8.8 km). Post-capture, minimum lengths of stay by Dunlin on the YKD were not significantly different between juveniles (median = 19 days) and adults (median = 23 days), with some birds staging for more than 50 days. Body mass at time of capture was the best single variable explaining length of stay on the YKD, with average length of stay decreasing by 2.5 days per additional gram of body mass at time of capture. Conservation efforts for postbreeding shorebirds should consider patterns of resource use that may differ not only by age cohort but also by individual condition.

  15. The Biogeochemical Response to Inter-decadal Atmospheric Forcing Across Watershed Scales in Canada's Subarctic

    Science.gov (United States)

    Spence, C.

    2016-12-01

    Rapid landscape changes in the circumpolar north have been documented, including degradation of permafrost and alteration of vegetation communities. These are widely expected to have profound impacts on the freshwater fluxes of solutes, carbon and nitrogen across the Arctic domain. However, there have been few attempts to document trends across the diversity of landscapes in the circumpolar north, mostly due to a dearth of long term data. Some of the fastest rates of warming over the last thirty years have occurred in Canada's Northwest Territories, so this region should already exhibit changes in aquatic chemistry. Observations of chemical loads in streams draining the ice-poor discontinuous permafrost subarctic Canadian Shield region were analyzed with the goal of determining how basins across scales have responded to changes in atmospheric forcing. Smaller streams, with much closer linkages to terrestrial processes, experienced a synchrony among hydrological and biogeochemical processes that enhanced chemical flux above that in their larger counterparts. This demonstrates that there are differences in resiliency and resistance across scales to climate change. These results highlight the importance of biogeochemical process understanding to properly explain and predict how chemical loading scales from headwaters to river mouths. This is important information if society is to properly adapt policies for effluent discharge, nearshore marine management, among others.

  16. Annual Energy Review 2007

    Energy Technology Data Exchange (ETDEWEB)

    Seiferlein, Katherine E. [USDOE Energy Information Administration (EIA), Washington, DC (United States)

    2008-06-01

    The Annual Energy Review (AER) is the Energy Information Administration's (EIA) primary report of annual historical energy statistics. For many series, data begin with the year 1949. Included are data on total energy production, consumption, and trade; overviews of petroleum, natural gas, coal, electricity, nuclear energy, renewable energy, international energy, as well as financial and environment indicators; and data unit conversion tables. Publication of this report is required under Public Law 95–91 (Department of Energy Organization Act), Section 205(c), and is in keeping with responsibilities given to the EIA under Section 205(a)(2), which states: “The Administrator shall be responsible for carrying out a central, comprehensive, and unified energy data and information program which will collect, evaluate, assemble, analyze, and disseminate data and information....”

  17. Late Holocene climate and chemical change at high latitudes: case studies from contaminated sites in subarctic and arctic Canada

    Science.gov (United States)

    Galloway, Jennifer M.; Cooney, Darryl; Crann, Carley; Falck, Hendrik; Howell, Dana; Jamieson, Heather; Macumber, Andrew; Nasser, Nawaf; Palmer, Michael; Patterson, R. Timothy; Parsons, Michael; Roe, Helen M.; Sanei, Hamed; Spence, Christopher; Stavinga, Drew; Swindles, Graeme T.

    2015-04-01

    Climate variability is occurring at unprecedented rates in northern regions of the Earth, yet little is known about the nature of this variability or its influence on chemical cycling in the environment, particularly in areas with a legacy of contamination from past resource development. We use a paleolimnological approach to reconstruct climate and chemical change over centuries and millennia at two sites in the mineral-rich Slave Geologic Province in Northern Canada heavily impacted by gold mining. Such an approach is necessary to define the cumulative effects of climate change on metal loading and can be used to define anthropogenic release of contaminants to support policy and regulation due to a paucity of long-term monitoring data. The Seabridge Gold Inc. Courageous Lake project is a gold exploration project 240 km north of Yellowknife in the central Northwest Territories, Arctic Canada. Mining operations took place within the claim area at the Tundra (1964-1968) and Salmita (1983-1987) mines. Giant Mine is located in the subarctic near the City of Yellowknife and mining at this site represents the longest continuous gold mining operation in Canada (1938 to 2002). Due to the refractory mineralogy of ore, gold was extracted from arsenopyrite by roasting, which resulted in release of substantial quantities of highly toxic arsenic trioxide to the environment. Arsenic (As) is also naturally elevated at these sites due its occurrence in Yellowknife Supergroup greenstone belts and surficial geologic deposits. To attempt to distinguish between geogenic and anthropogenic sources of As and characterize the role of climate change on metalloid mobility we used a freeze coring technology to capture lake sediments from the properties. Sediments were analyzed for sedimentary grain size and bulk geochemistry using ICP-MS to reconstruct climate and chemical change. Micropaleontological analyses are on-going. Interpretations of the physical, chemical, and biological archive

  18. Seasonal calcareous nannoplankton and other biogenic particle fluxes for 1990-2009: twenty-year long records from the central subarctic Pacific Ocean and the Bering Sea

    Science.gov (United States)

    Takahashi, Kozo; Tsutsui, Hideto

    2017-04-01

    and NOAA, it appears likely that siliceous phytoplankton such as diatoms and silicoflagellates is more dependent on high nutrient conditions than calcareous nannoplankton requires. Calcareous nannoplankton, on the other hand, appears to require rather narrow own species range of temperatures while nutrient requirement may not be as strict as those by siliceous microplankton. Within the two calcareous nannoplankton taxa, it is clear that C. pelagicus has higher nutrient dependency than E. huxleyi. Essentially, calcareous nannoplankton can still produce in November [actual production in surface water in October] when solar intensity decreases significantly, as long as temperatures are still appropriate. By this time of the year most siliceous phytoplankton had more or less completed bulk of their annual production. Exceptions for this are rather limited characteristic species that are adapted in dim light but high nutrients such as Coscinodiscus marginatus (diatom) and Dictyocha mandarai (silicoflagellate) in the subarctic Pacific (Takahashi et al., 1989).

  19. Plutonium and cesium radionuclides in the Hudson River Estuary and other environments. Annual technical progress report, 1 December 1977--30 November 1978

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, H. J.; Trier, R. M.

    1978-01-01

    Radionuclide activities were measured in a large number of sediment cores and suspended particle samples throughout the salinity range of the Hudson River estuary. Activities of /sup 137/Cs, /sup 134/Cs, and /sup 60/Co determined by gamma spectrometry and /sup 239/,/sup 240/Pu and /sup 238/Pu determined by alpha spectrometry indicate reasonably rapid accumulation rates in the sediments of marginal cove areas, and very rapid deposition in the harbor region adjacent to New York City. General distributions of /sup 137/Cs and /sup 239/,/sup 240/Pu are similar in surface sediments and with depth in cores, but there are deviations from the fallout ratio due to (1) addition of reactor /sup 137/Cs and (2) loss of /sup 137/Cs from the particle phases at higher salinities. Measurable amounts of reactor-derived /sup 134/Cs and /sup 60/Co are found in nearly all sediment samples containing appreciable /sup 137/Cs between 15 Km upstream of Indian Point and 70 Km south of the reactor. Accumulations of /sup 239/,/sup 240/Pu in New York harbor sediments are more than an order of magnitude greater than the fallout delivery rate. Depth profiles of radionuclides and variations of activities with particle size at low salinities in the Hudson indicate the importance of organic phases, including large flocculent particles greater than 180..mu.., in binding plutonium, and no evidence of significant chemical migration within the sediments. Measurements of water column fallout /sup 239/,/sup 240/Pu in a saline lake with a high carbonate ion concentration yielded activities about two orders of magnitude greater than has been found for fallout plutonium in other continental waters, indicating extensive mobility in some natural water environments.

  20. Plutonium, cesium and uranium series radionuclides in the Hudson River estuary and other environments. Annual technical progress report, December 1, 1979-November 30, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, H. J.; Trier, R. M.; Olsen, C. R.

    1980-01-01

    Radionuclide activities were measured in a large number of sediment cores and suspended particle samples throughout the salinity range of the Hudson River estuary. Activities of /sup 137/Cs, /sup 134/Cs and /sup 60/Co determined by gamma spectrometry and /sup 239/ /sup 240/Pu and /sup 238/Pu determined by alpha spectrometry indicate reasonably rapid accumulation rates in the sediments of marginal cove areas, and very rapid deposition in the harbor region adjacent to New York City, resulting in /sup 239/ /sup 240/Pu accumulations there more than an order of magnitude greater than the fallout delivery rate. Measurable amounts of reactor-derived /sup 134/Cs and /sup 60/Co are found in nearly al sediment samples containing appreciable /sup 137/Cs between 15 km upstream of Indian Point and the downstream extent of our sampling about 70 km south of the reactor. Fallout /sup 239/ /sup 240/Pu reaching the Hudson appears to be almost completely retained within the systems by particle deposition, while 70 to 90% of the /sup 137/Cs derived from both reactor releases and fallout has been exported to the coastal waters in solution. Activity levels of /sup 239/ /sup 240/Pu in New York harbor sediments indicate a significant source in addition to suspended particles carried down the Hudson. The most likely cause appears to be transport into the estuary of particles from offshore waters having higher specific activities of /sup 239/ /sup 240/Pu. Measurements of fallout /sup 239/ /sup 240/Pu in a saline lake with a high carbonate ion concentration yielded water column activities about two orders of magnitude greater than has been found for fallout plutonium in other continental waters, indicating extensive mobility in some natural water environments. Experiments using lake water suggest that carbonate ion may indeed be a critical factor in regulating plutonium solubility and that low molecular weight complexes are primarily responsible for enhanced plutonium solubility.

  1. What matters 2013. Construction and housing: Homes of tomorrow and beyond. Noise: Leaf blowers and engines. Protection of the marine environment: A blue economy - Threat or opportunity for the oceans? Annual report of the Federal Environment Agency

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-11-01

    As of 2011, more people worldwide live in cities than in the country. The global consumption of resources, energy of heating, cooling or light, and daily environmental conditions such as air and noise pollution are very much characterised by the way we organise our cities. Although at the beginning of the industrial age, cities often were hostile, dirty and noisy places, they appealed greatly to the rural population. Today, the environmental quality of urban spaces in highly-developed countries has improved immensely. Hence, even in German, urban areas have been able to show a small population increase in the past few years. Under this aspect, the paper under consideration consists of the following contributions: (a) The EU and the two-degree limit (The many advantages of Germany's pioneering role); (b) Homes of tomorrow and beyond (A central sector for climate and site protection, the energy revolution and health); (c) Leaf blowers and engines (The struggle against noise pollution must include people); (d) A blue economy - threat or opportunity for the oceans? (Overfishing, enthrophication, contaminants and litter are threatening the oceans, but there are solutions); (e) Certificate for renewable energy (Te Federal Environment Agency's proof of origin); (f) On the gas trail (Our air monitoring network records air pollution, across borders and globally); (g) the environmental specimen bank (Environmental observation with samples from humans and the environment).

  2. Subarctic wintertime dissolved iron speciation driven by thermal constraints on Fe(II) oxidation, dissolved organic matter and stream reach

    Science.gov (United States)

    Morita, Yuichiroh; Yamagata, Kei; Oota, Atsuki; Ooki, Atsushi; Isoda, Yutaka; Kuma, Kenshi

    2017-10-01

    We studied the seasonal variations in Fe(II), Fe(III), humic-like dissolved organic matter (DOM), nitrate and nitrite (NO3 + NO2), and silicate (Si(OH)4) in river waters of three subarctic rivers flowing into Hakodate Bay in southwestern Hokkaido, Japan from May 2010 to February 2014. High Fe(II) concentrations were detected in winter at the sampling sites where the river bottom was comprised of sandy or silty sediment, primarily the lower and middle reaches of the rivers. Conversely, from early spring to late autumn Fe(II) levels were low or undetectable. We infer that soluble Fe(II) concentration in these subarctic river waters is driven by the balance between the influx of Fe(II) to the river and the Fe(II) oxidation rates that determines the dynamics in Fe(II) concentration in the river water. The Fe(II) may originate from reductive dissolution of Fe(III) in the river sediment or from Fe(II)-bearing groundwater. The latter seems to be the most likely source during winter time. The high Fe(II) concentrations during winter is predominantly attributed to the extremely slow oxidation rate of Fe(II) to Fe(III) at low water temperature rather than to an actual increase in the flux of reduced Fe(II). Nevertheless, we propose that the flux of reduced Fe(II) from river sediments and groundwater in lowland area of the catchment to overlying river waters might be the most important sources of iron in river waters. This provides an important insight into the role of river processes and the interaction between climate and river morphology in determining the inputs of iron to subarctic coastal marine waters.

  3. Measuring the relative resilience of subarctic lakes to global change: redundancies of functions within and across temporal scales

    Science.gov (United States)

    Angeler, David G.; Allen, Craig R.; Johnson, Richard K.

    2013-01-01

    1. Ecosystems at high altitudes and latitudes are expected to be particularly vulnerable to the effects of global change. We assessed the responses of littoral invertebrate communities to changing abiotic conditions in subarctic Swedish lakes with long-term data (1988–2010) and compared the responses of subarctic lakes with those of more southern, hemiboreal lakes. 2. We used a complex systems approach, based on multivariate time-series modelling, and identified dominant and distinct temporal frequencies in the data; that is, we tracked community change at distinct temporal scales. We determined the distribution of functional feeding groups of invertebrates within and across temporal scales. Within and cross-scale distributions of functions have been considered to confer resilience to ecosystems, despite changing environmental conditions. 3. Two patterns of temporal change within the invertebrate communities were identified that were consistent across the lakes. The first pattern was one of monotonic change associated with changing abiotic lake conditions. The second was one of showing fluctuation patterns largely unrelated to gradual environmental change. Thus, two dominant and distinct temporal frequencies (temporal scales) were present in all lakes analysed. 4. Although the contribution of individual feeding groups varied between subarctic and hemiboreal lakes, they shared overall similar functional attributes (richness, evenness, diversity) and redundancies of functions within and between the observed temporal scales. This highlights similar resilience characteristics in subarctic and hemiboreal lakes. 5. Synthesis and applications. The effects of global change can be particularly strong at a single scale in ecosystems. Over time, this can cause monotonic change in communities and eventually lead to a loss of important ecosystem services upon reaching a critical threshold. Dynamics at other spatial or temporal scales can be unrelated to environmental change

  4. Distributions and seasonal abundances of krill eggs and larvae in the sub-Arctic Godthåbsfjord, SW Greenland

    DEFF Research Database (Denmark)

    Teglhus, Frederik Wolff; Agersted, Mette Dalgaard; Akther, Hasna

    2015-01-01

    The larval krill community (Thysanoessa spp.) was investigated along the sub-Arctic Godthåbsfjord, SW Greenland, in June 2010. In addition, the progress of krill development from egg to furcilia was studied from March to August 2010 in a fjord branching off the Godthåbsfjord. Krill spawned from...... and furcilia stages lasted 22 and 63 d, respectively. The growth rate from metanauplius to calyptopis was 0.12 d−1, while the growth rate across all developmental stages was 0.05 d−1. Mortality rates were calculated as 25% from eggs to nauplii, 48% from eggs to calyptopes and 83% from eggs to furcilia. During...

  5. Wetland development, permafrost history and nutrient cycling inferred from late Holocene peat and lake sediment records in subarctic Sweden

    DEFF Research Database (Denmark)

    Kokfelt, U.; Reuss, N.; Struyf, E.

    2010-01-01

    -induced changes in hydrology may further have affected the inflow of alkaline water from the catchment. Elevated contents of biogenic silica and diatom pigments in lake sediments during periods of poor fen and bog expansion further indicate that terrestrial vegetation influenced the amount of nutrients entering...... insight into nutrient and permafrost dynamics in a subarctic wetland and imply that continued permafrost decay and related vegetation changes towards minerotrophy may increase carbon and nutrient storage of mire deposits and reduce nutrient fluxes in runoff. Rapid permafrost degradation may on the other...

  6. Institute annual report 2004

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    The mission of the ITU (Institute for Transuranium Elements) is to protect the European citizen against risk associated with the handling and storage of highly radioactive elements. The JRC (Joint Research Center) provide customer-driven scientific and technical support for the conception, development, implementation and monitoring of EU policies. In this framework this annual report presents the TU actions in: basic actinide research, spent fuel characterization, safety of nuclear fuels, partitioning and transmutation, alpha-immunotherapy/radiobiology, measurement of radioactivity in the environment, safeguards research and development. (A.L.B.)

  7. Ozone variability and halogen oxidation within the Arctic and sub-Arctic springtime boundary layer

    Directory of Open Access Journals (Sweden)

    J. B. Gilman

    2010-11-01

    Full Text Available The influence of halogen oxidation on the variabilities of ozone (O3 and volatile organic compounds (VOCs within the Arctic and sub-Arctic atmospheric boundary layer was investigated using field measurements from multiple campaigns conducted in March and April 2008 as part of the POLARCAT project. For the ship-based measurements, a high degree of correlation (r = 0.98 for 544 data points collected north of 68° N was observed between the acetylene to benzene ratio, used as a marker for chlorine and bromine oxidation, and O3 signifying the vast influence of halogen oxidation throughout the ice-free regions of the North Atlantic. Concurrent airborne and ground-based measurements in the Alaskan Arctic substantiated this correlation and were used to demonstrate that halogen oxidation influenced O3 variability throughout the Arctic boundary layer during these springtime studies. Measurements aboard the R/V Knorr in the North Atlantic and Arctic Oceans provided a unique view of the transport of O3-poor air masses from the Arctic Basin to latitudes as far south as 52° N. FLEXPART, a Lagrangian transport model, was used to quantitatively determine the exposure of air masses encountered by the ship to first-year ice (FYI, multi-year ice (MYI, and total ICE (FYI+MYI. O3 anti-correlated with the modeled total ICE tracer (r = −0.86 indicating that up to 73% of the O3 variability measured in the Arctic marine boundary layer could be related to sea ice exposure.

  8. Diurnal Variations of CH4 and CO2 Exchange in a Sub-Arctic Peatland Ecosystem

    Science.gov (United States)

    Berg, A.; Oquist, M. G.; Svensson, B. H.

    2003-04-01

    We investigated the diurnal variations of CH_4 and CO_2 fluxes from a sub-arctic peatland ecosystem in order to evaluate short-term controls on exchange dynamics and the importance of vascular plant photosynthetic activity. The study site was a semi-dry ombrotrophic habitat with a vascular plant community dominated by Eriophorum vaginatum L. and Carex rotundata Whalenb. Measurements were carried out at six sub-sites, three controls and three that were shaded with sack cloth in order to reduce the magnitude and extent of photosynthetic activity. Gas exchange rates, soil temperatures and porewater concentrations of methane and acetate were measured at 2--4 h intervals during a cloud-free diurnal cycle. During the day the variations in methane flux had the same temporal pattern as the gross photosynthetic rate and in combination with porewater acetate concentrations it could explain ca 60% of the variation. Average CH_4 emission rates tended to be higher during the night and correlated best with porewater CH_4 concentrations (r^2 > 0.9). When photosynthesis seized in the evening it was associated with an increase of acetate concentrations in the rhizosphere. This was followed by increases in porewater CH_4 concentrations and concomitant higher CH_4 flux rates with a lag of ca 2--4 h. The same pattern could be observed at both control and shaded sub-sites, but occurred earlier in the shaded, probably owing to an earlier decrease in light intensities. Apart from these substrate-based interactions we also found evidence confirming the importance of vascular plants in mediating CH_4 transport, and results suggest that this was linked to stomatal conductance. Our observations further stress the importance of vascular plant influence on CH_4 exchange dynamics from northern peatlands, and also add a new dimension to the complexities involved in these interactions.

  9. Future stratospheric ozone depletion will affect a subarctic dwarf shrub ecosystem

    Energy Technology Data Exchange (ETDEWEB)

    Johanson, Ulf

    1997-02-01

    The stratospheric ozone depletion and the concomitant increase in ultraviolet-B (UV-B, 280-320 nm) radiation is of global concern due to the effects of UV-B on living organisms. To investigate the effects of increased levels of UV-B, a field irradiation system was established at a subarctic dwarf shrub heath in Northern Sweden (68 deg N). An ozone depletion of 15% under clear sky conditions was simulated over a naturally growing ecosystem. The response of both individual components and processes was studied to reveal changes in ecosystem structure and function. Species with different life strategies (evergreen or deciduous) responded differently both in magnitude and direction. The evergreen species were more responsive to UV-B regarding shoot growth, which could be due to cumulative effects in long-lived tissues, since the retardation in relative growth increased over time of exposure. Leaves of evergreen species became thicker under enhanced UV-B, while leaves of deciduous species became thinner. Decomposition studies (laboratory and in situ) showed that indirect effects of UV-B, due to changes in leaf tissue chemistry affected microbial activity and slowed down the decomposition rate. More directly, UV-B decreased the abundance of some fungal species and hence the composition of species. However, no altered decomposition rate was found when decomposition progressed under high UV-B even if the microorganisms were fewer. This could be due to the increased direct photo degradation of litter that compensates for lower microbial activity. The decomposition rate is therefore strongly dependent on the interception of UV-B at the litter layer. This research has shown that ecosystem components and processes are affected in a number of ways and that there are indications of changes in species composition in a long-term perspective due to differences in responsiveness between the different species. 128 refs, 7 figs

  10. Nitrogen isotope variations in the subarctic northeast Pacific: relationships to nitrate utilization and trophic structure

    Science.gov (United States)

    Wu, Jinping; Calvert, S. E.; Wong, C. S.

    1997-02-01

    The isotopic composition of dissolved nitrate, size-fractionated suspended particulate organic matter (SPOM) and zooplankton was determined on a transect (Line P) between a coastal upwwelling domain and Station Papa in the subarctic northeast Pacific. Station Papa lies in one of the three extensive high-nutrient low-chlorophyll (HNLC) domains of the open ocean, where plankton standing stocks are seasonally uniform and production is lower than the potential production based on available nutrients. In spring 1993, surface water δ15NO 3- decreased from east to west along the transect, from ca 12%. in the coastal domain to 8%. at Station Papa, while nitrate concentration ([N0 3-) increased from 3 to 12 μM in the same direction. Concurrently, δ15NO 3- at 400 m depth showed a much smaller change, from 5.3 to 3.1%., indicating a larger δ15N difference between deep and surface waters at the coastal end of the transect. The isotopic trend for SPOM was similar, from approximately 11 to 3%. for bulk SPOM, 8.5 to 3%. for the ocean where [NO 3-] > 7 μM, it increases rapidly where nitrate utilization is high (that is, where biological uptake is greater than physical supply), and it decreases during upwelling events when physical supply of nutrients overwhelms the biological uptake rate. Finally, the nitrogen isotopes show the expected trophic enrichment 15N, with bulk zooplankton being isotopically heavier than SPOM by 3.9%. at Station Papa and 2.2%. in the coastal domain. This difference possibly reflects the existence of a relatively short food chain in the coastal domain and a longer food chain, involving microzooplanktonic grazers, at Station Papa. The range of δ15N among seven zooplankton groups was 3.7%., the data suggesting an increasing trophic hierarchy: pteropods, salps, euphausiids, copepods-medusaeamphipods, chaetognaths.

  11. The emission of carbon dioxide from soils of the Pasvik nature reserve in the Kola Subarctic

    Science.gov (United States)

    Kadulin, M. S.; Smirnova, I. E.; Koptsyk, G. N.

    2017-09-01

    The emission of carbon dioxide (CO2) from podzols (Albic Podzols (Arenic)) and the factors controlling its spatiotemporal variability in the forest ecosystems of the Pasvik Reserve in the Kola Subarctic are characterized. Relatively favorable climatic conditions beyond the polar circle in summer are responsible for intensive soil respiration. The type of forest affects the emission of CO2 from the soil surface. The lowest rate of the CO2 emission is typical of the soils under lichen pine forest (105-220 mg C/(m2 h) or 180 g C/m2 during the summertime). Higher rates are observed for the soils under green moss pine (170-385 mg C/(m2 h) or 360 g C/m2 during the summertime) and birch (190-410 mg C/(m2 h) or 470 g C/m2 during the summertime) forests. This may related to a higher contribution of root respiration (44, 88, and 67%, respectively). Soil respiration and the contribution of root respiration to it increase with an increase in the canopy density; mass of small roots; microbial biomass; depth of the stony layer; soil moistening; and the contents of available carbon, nitrogen, phosphorus, and potassium compounds. At the same time, they decrease with an increase in the portion of lichens in the ground cover. The seasonal dynamics are characterized by the CO2 emission maximums in the summer and fall and minimum in the spring. The daily dynamics are smoothed under conditions of the polar day.

  12. Performance of an experimental wastewater treatment high-rate algal pond in subarctic climate.

    Science.gov (United States)

    Grönlund, Erik; Hanaeus, Jörgen; Johansson, Erica; Falk, Stefan

    2010-01-01

    A pilot-scale experimental high-rate algal pond (HRAP) was investigated in the subarctic mid-Sweden region, at latitude 63 degrees N. During autumn 2002, conditions included temperatures below 10 degrees C and photosynthetic active radiation below 200 microE/m2 x s. Biochemical oxygen demand was reduced by approximately 90% (approximately 40 g/m3), chemical oxygen demand by 65% (approximately 80 g/m3), total phosphorus by 20% (approximately 1 g/m3), and total nitrogen by 46% (approximately 15 g/m3), at a retention time of approximately 2.5 days. During autumn 2003, the performance of the HRAP appeared better with a more dense microalgae culture; however, as a result of poor settling of the microalgae, the reduction was considerably lower. A major difference between the years was the microalgae composition. In 2002, the large green algae Coelastrum dominated with Chlamydomonas, Scenedesmus, Lagerheimia, and the Cryptophyte Rhodomonas. In 2003, there was a total dominance of the very small green algae Chlorella, known to be difficult to settle. In batch growth experiments during spring 2002, doubling times of 4 to 6 days were achieved. The period of temperatures above 10 degrees C and an insolation of more than approximately 270 uE/m2 x s (125 Langleys), which is well-documented as appropriate for HRAP function (Oswald, 1988a, 1988c), were measured to last for 4 to 4.5 months from early May to late September. However, the growth and treatment performance experiments indicated that a longer season may be possible-6.5 to 7 months, at best-from early April to late October.

  13. Winter Insulation By Snow Accumulation in a Subarctic Treeline Ecosystem Increases Summer Carbon Cycling Rates

    Science.gov (United States)

    Parker, T.; Subke, J. A.; Wookey, P. A.

    2014-12-01

    The effect of snow accumulation on soil carbon and nutrient cycling is attracting substantial attention from researchers. We know that deeper snow accumulation caused by high stature vegetation increases winter microbial activity and therefore carbon and nitrogen flux rates. However, until now the effect of snow accumulation, by buffering winter soil temperature, on subsequent summer soil processes, has scarcely been considered. We carried out an experiment at an alpine treeline in subarctic Sweden in which soil monoliths, contained within PVC collars, were transplanted between forest (deep winter snow) and tundra heath (shallow winter snow). We measured soil CO2efflux over two growing seasons and quantified soil microbial biomass after the second winter. We showed that respiration rates of transplanted forest soil were significantly reduced compared with control collars (remaining in the forest) as a consequence of colder, but more variable, winter temperatures. We hypothesised that microbial biomass would be reduced in transplanted forests soils but found there was no difference compared to control. We therefore further hypothesised that the similarly sized microbial pool in the control is assembled differently to the transplant. We believe that the warmer winters in forests foster more active consortia of decomposer microbes as a result of different abiotic selection pressures. Using an ecosystem scale experimental approach, we have identified a mechanism that influences summer carbon cycling rates based solely on the amount of snow that accumulates the previous winter. We conclude that modification of snow depth as a consequence of changes in vegetation structure is an important mechanism influencing soil C stocks in ecosystems where snow persists for a major fraction of the year.

  14. Cryoprotectants and extreme freeze tolerance in a subarctic population of the wood frog.

    Directory of Open Access Journals (Sweden)

    Jon P Costanzo

    Full Text Available Wood frogs (Rana sylvatica exhibit marked geographic variation in freeze tolerance, with subarctic populations tolerating experimental freezing to temperatures at least 10-13 degrees Celsius below the lethal limits for conspecifics from more temperate locales. We determined how seasonal responses enhance the cryoprotectant system in these northern frogs, and also investigated their physiological responses to somatic freezing at extreme temperatures. Alaskan frogs collected in late summer had plasma urea levels near 10 μmol ml-1, but this level rose during preparation for winter to 85.5 ± 2.9 μmol ml-1 (mean ± SEM in frogs that remained fully hydrated, and to 186.9 ± 12.4 μmol ml-1 in frogs held under a restricted moisture regime. An osmolality gap indicated that the plasma of winter-conditioned frogs contained an as yet unidentified osmolyte(s that contributed about 75 mOsmol kg-1 to total osmotic pressure. Experimental freezing to -8°C, either directly or following three cycles of freezing/thawing between -4 and 0°C, or -16°C increased the liver's synthesis of glucose and, to a lesser extent, urea. Concomitantly, organs shed up to one-half (skeletal muscle or two-thirds (liver of their water, with cryoprotectant in the remaining fluid reaching concentrations as high as 0.2 and 2.1 M, respectively. Freeze/thaw cycling, which was readily survived by winter-conditioned frogs, greatly increased hepatic glycogenolysis and delivery of glucose (but not urea to skeletal muscle. We conclude that cryoprotectant accrual in anticipation of and in response to freezing have been greatly enhanced and contribute to extreme freeze tolerance in northern R. sylvatica.

  15. Physical and chemical characteristics of lakes across heterogeneous landscapes in arctic and subarctic Alaska

    Science.gov (United States)

    Larsen, A. S.; O'Donnell, J. A.; Schmidt, J. H.; Kristenson, H. J.; Swanson, D. K.

    2017-04-01

    Lakes are an important component of high-latitude regions, providing habitat for fish and wildlife and playing a critical role in biogeochemical and global carbon cycles. High-latitude lakes are sensitive to climate change, in part due to their development within permafrost soils. Considerable heterogeneity exists across arctic and subarctic landscapes, yet little is known about how this landscape variability influences chemical and physical attributes of lakes. We investigated the physical and chemical limnology of 617 lakes in Alaska's boreal forest and boreal-arctic transition zone. We categorized lakes into 10 basin types based on parent material, topography, genesis, and permafrost characteristics. Physical parameters varied across lake basin types, with the deepest lakes occurring in ice-poor glacial deposits and ice-rich terrain, while the shallowest lakes were observed in floodplain deposits and coastal lowlands. Dissolved inorganic nitrogen (N) and phosphorous (P) concentrations were generally low across all landscapes, whereas total N and P were highest in lakes underlain by ice-rich Pleistocene loess. Total N and P concentrations were significantly correlated with chlorophyll a, indicating a possible colimitation of primary productivity in these systems. Base cation concentrations helped elucidate lake basin hydrology and the relative influence of shallow versus deep groundwater inputs to surface water. Using these results, we developed a simple conceptual model for each lake and landscape type based on differences in physical and chemical parameters. Overall, we expect that the vulnerability of lake ecosystems to climate change will vary across lake basin types and will be mediated by spatial patterns in permafrost characteristics and subsurface hydrology.

  16. Bioavailable soil phosphorus decreases with increasing elevation in a subarctic tundra landscape.

    Directory of Open Access Journals (Sweden)

    Andrea G Vincent

    Full Text Available Phosphorus (P is an important macronutrient in arctic and subarctic tundra and its bioavailability is regulated by the mineralization of organic P. Temperature is likely to be an important control on P bioavailability, although effects may differ across contrasting plant communities with different soil properties. We used an elevational gradient in northern Sweden that included both heath and meadow vegetation types at all elevations to study the effects of temperature, soil P sorption capacity and oxalate-extractable aluminium (Alox and iron (Feox on the concentration of different soil P fractions. We hypothesized that the concentration of labile P fractions would decrease with increasing elevation (and thus declining temperature, but would be lower in meadow than in heath, given that N to P ratios in meadow foliage are higher. As expected, labile P in the form of Resin-P declined sharply with elevation for both vegetation types. Meadow soils did not have lower concentrations of Resin-P than heath soils, but they did have 2-fold and 1.5-fold higher concentrations of NaOH-extractable organic P and Residual P, respectively. Further, meadow soils had 3-fold higher concentrations of Alox + Feox and a 20% higher P sorption index than did heath soils. Additionally, Resin-P expressed as a proportion of total soil P for the meadow was on average half that in the heath. Declining Resin-P concentrations with elevation were best explained by an associated 2.5-3.0 °C decline in temperature. In contrast, the lower P availability in meadow relative to heath soils may be associated with impaired organic P mineralization, as indicated by a higher accumulation of organic P and P sorption capacity. Our results indicate that predicted temperature increases in the arctic over the next century may influence P availability and biogeochemistry, with consequences for key ecosystem processes limited by P, such as primary productivity.

  17. Bioavailable soil phosphorus decreases with increasing elevation in a subarctic tundra landscape.

    Science.gov (United States)

    Vincent, Andrea G; Sundqvist, Maja K; Wardle, David A; Giesler, Reiner

    2014-01-01

    Phosphorus (P) is an important macronutrient in arctic and subarctic tundra and its bioavailability is regulated by the mineralization of organic P. Temperature is likely to be an important control on P bioavailability, although effects may differ across contrasting plant communities with different soil properties. We used an elevational gradient in northern Sweden that included both heath and meadow vegetation types at all elevations to study the effects of temperature, soil P sorption capacity and oxalate-extractable aluminium (Alox) and iron (Feox) on the concentration of different soil P fractions. We hypothesized that the concentration of labile P fractions would decrease with increasing elevation (and thus declining temperature), but would be lower in meadow than in heath, given that N to P ratios in meadow foliage are higher. As expected, labile P in the form of Resin-P declined sharply with elevation for both vegetation types. Meadow soils did not have lower concentrations of Resin-P than heath soils, but they did have 2-fold and 1.5-fold higher concentrations of NaOH-extractable organic P and Residual P, respectively. Further, meadow soils had 3-fold higher concentrations of Alox + Feox and a 20% higher P sorption index than did heath soils. Additionally, Resin-P expressed as a proportion of total soil P for the meadow was on average half that in the heath. Declining Resin-P concentrations with elevation were best explained by an associated 2.5-3.0 °C decline in temperature. In contrast, the lower P availability in meadow relative to heath soils may be associated with impaired organic P mineralization, as indicated by a higher accumulation of organic P and P sorption capacity. Our results indicate that predicted temperature increases in the arctic over the next century may influence P availability and biogeochemistry, with consequences for key ecosystem processes limited by P, such as primary productivity.

  18. American mastodon extirpation in the Arctic and Subarctic predates human colonization and terminal Pleistocene climate change.

    Science.gov (United States)

    Zazula, Grant D; MacPhee, Ross D E; Metcalfe, Jessica Z; Reyes, Alberto V; Brock, Fiona; Druckenmiller, Patrick S; Groves, Pamela; Harington, C Richard; Hodgins, Gregory W L; Kunz, Michael L; Longstaffe, Fred J; Mann, Daniel H; McDonald, H Gregory; Nalawade-Chavan, Shweta; Southon, John R

    2014-12-30

    Existing radiocarbon ((14)C) dates on American mastodon (Mammut americanum) fossils from eastern Beringia (Alaska and Yukon) have been interpreted as evidence they inhabited the Arctic and Subarctic during Pleistocene full-glacial times (∼ 18,000 (14)C years B.P.). However, this chronology is inconsistent with inferred habitat preferences of mastodons and correlative paleoecological evidence. To establish a last appearance date (LAD) for M. americanum regionally, we obtained 53 new (14)C dates on 36 fossils, including specimens with previously published dates. Using collagen ultrafiltration and single amino acid (hydroxyproline) methods, these specimens consistently date to beyond or near the ∼ 50,000 y B.P. limit of (14)C dating. Some erroneously "young" (14)C dates are due to contamination by exogenous carbon from natural sources and conservation treatments used in museums. We suggest mastodons inhabited the high latitudes only during warm intervals, particularly the Last Interglacial [Marine Isotope Stage (MIS) 5] when boreal forests existed regionally. Our (14)C dataset suggests that mastodons were extirpated from eastern Beringia during the MIS 4 glacial interval (∼ 75,000 y ago), following the ecological shift from boreal forest to steppe tundra. Mastodons thereafter became restricted to areas south of the continental ice sheets, where they suffered complete extinction ∼ 10,000 (14)C years B.P. Mastodons were already absent from eastern Beringia several tens of millennia before the first humans crossed the Bering Isthmus or the onset of climate changes during the terminal Pleistocene. Local extirpations of mastodons and other megafaunal populations in eastern Beringia were asynchrononous and independent of their final extinction south of the continental ice sheets.

  19. Cryoprotectants and extreme freeze tolerance in a subarctic population of the wood frog.

    Science.gov (United States)

    Costanzo, Jon P; Reynolds, Alice M; do Amaral, M Clara F; Rosendale, Andrew J; Lee, Richard E

    2015-01-01

    Wood frogs (Rana sylvatica) exhibit marked geographic variation in freeze tolerance, with subarctic populations tolerating experimental freezing to temperatures at least 10-13 degrees Celsius below the lethal limits for conspecifics from more temperate locales. We determined how seasonal responses enhance the cryoprotectant system in these northern frogs, and also investigated their physiological responses to somatic freezing at extreme temperatures. Alaskan frogs collected in late summer had plasma urea levels near 10 μmol ml-1, but this level rose during preparation for winter to 85.5 ± 2.9 μmol ml-1 (mean ± SEM) in frogs that remained fully hydrated, and to 186.9 ± 12.4 μmol ml-1 in frogs held under a restricted moisture regime. An osmolality gap indicated that the plasma of winter-conditioned frogs contained an as yet unidentified osmolyte(s) that contributed about 75 mOsmol kg-1 to total osmotic pressure. Experimental freezing to -8°C, either directly or following three cycles of freezing/thawing between -4 and 0°C, or -16°C increased the liver's synthesis of glucose and, to a lesser extent, urea. Concomitantly, organs shed up to one-half (skeletal muscle) or two-thirds (liver) of their water, with cryoprotectant in the remaining fluid reaching concentrations as high as 0.2 and 2.1 M, respectively. Freeze/thaw cycling, which was readily survived by winter-conditioned frogs, greatly increased hepatic glycogenolysis and delivery of glucose (but not urea) to skeletal muscle. We conclude that cryoprotectant accrual in anticipation of and in response to freezing have been greatly enhanced and contribute to extreme freeze tolerance in northern R. sylvatica.

  20. Climate change and mercury accumulation in Canadian high and subarctic lakes.

    Science.gov (United States)

    Kirk, Jane L; Muir, Derek C M; Antoniades, Dermot; Douglas, Marianne S V; Evans, Marlene S; Jackson, Togwell A; Kling, Hedy; Lamoureux, Scott; Lim, Darlene S S; Pienitz, Reinhard; Smol, John P; Stewart, Kailey; Wang, Xiaowa; Yang, Fan

    2011-02-01

    Mercury (Hg) profiles were compared to profiles of climate indicators including microfossil remains and algal-derived or S2 carbon (C) in dated sediment cores from 14 lakes spanning latitudinal and longitudinal gradients across the Canadian high and subarctic. Hg fluxes increased postindustrialization (post-∼1850) in 11 of these lakes (postindustrialization Hg fluxes (ΔHgF(F)) = 2-24 μg m(-2) y(-1)). Correction of HgF(F) for catchment contributions demonstrated that Hg deposition originating from catchment-independent factors, such as atmospheric deposition, increased since industrialization in all 14 lakes. Several of these lakes also showed postindustrial shifts in algal assemblages consistent with climate-induced changes. Eleven lakes showed post-1850s increases in S2F(F), suggesting that lake primary productivity has recently increased in the majority of our sites (ΔS2F(F) = 0.1-4 g m(-2) y(-1)). Other studies have interpreted significant relationships between Hg:S2 concentrations in Arctic sediment as support for the algal scavenging hypothesis, which postulates that Hg fluxes to Arctic sediments are largely driven by S2. However, in six of our lakes we observed no Hg:S2 relationship, and in one lake a significant negative Hg:S2 relationship was observed due to increased Hg and decreased S2 C deposition during the postindustrialization period. In six of the seven lakes where a significant positive Hg:S2 relationship was observed, algal assemblages either did not change through time or the timing of the shifts did not correspond to changes in Hg deposition. Our results demonstrate that, although Arctic lakes are experiencing a myriad of changes, including increased Hg and S2 deposition or changing algal assemblages, increased lake primary productivity does not appear to be driving changes in Hg fluxes to sediments.

  1. Geomorphic (de-) coupling of hillslope and channel systems within headwater catchments in two subarctic tributary valleys, Nordfjord, Western Norway

    Science.gov (United States)

    Laute, Katja; Beylich, Achim A.

    2010-05-01

    Hillslopes occupy large areas of the earth surface. Studying the characteristics, development and interaction of hillslopes as components of the geomorphic hillslope-channel coupling process-response system will improve the understanding of the complex response of mountain landscape formation. The rates of hillslope processes are exceptionally varied and affected by many influences of varying intensity. Hillslope-channel coupling and sediment storage within slopes are important factors that influence sediment delivery through catchments, especially in steep environments. Within sediment transfers from sources to sinks in drainage basins, hillslopes function as a key element concerning sediment storage, both for short term periods as between rainstorms as well as for longer periods in colluvial deposits. This PhD project is part of the NFR funded SedyMONT-Norway project within the ESF TOPO-EUROPE SedyMONT (Timescales of sediment dynamics, climate and topographic change in mountain landscapes) programme. The focus of this study is on geomorphic hillslope-channel coupling or de-coupling and sediment transport within four distinct headwater areas of the Erdalen and Bødalen catchments in the Nordfjord valley-fjord system (inner Nordfjord, Western Norway). Both catchments can be described as steep, U-shaped and glacier-fed, subarctic tributary valleys. Approximately 14% of the 49 km2 large headwater area of Erdalen is occupied by hillslope deposits; in Bødalen hillslope deposits occupy 12% of the 42 km2 large headwater area. The main aims of the study are to present preliminary findings on (i) the identification of possible sediment sources and delivery pathways within the headwater areas of the catchments, (ii) to analyze the development of hillslope-channel coupling / de-coupling from postglacial to contemporary timescales as well as (iii) to investigate the current degree of geomorphic hillslope-channel coupling within the different headwater catchments and (iv) to

  2. Long-Term Acid-Generating and Metal Leaching Potential of a Sub-Arctic Oil Shale

    Directory of Open Access Journals (Sweden)

    Kathryn A. Mumford

    2014-04-01

    Full Text Available Shales are increasingly being exploited for oil and unconventional gas. Exploitation of sub-arctic oil shales requires the creation of gravel pads to elevate workings above the heaving effects of ground ice. These gravel pads can potentially generate acidic leachate, which can enhance the mobility of metals from the shale. To examine this potential, pyrite-bearing shale originating from sub-Arctic gravel pad sites were subjected to leaching tests for 600 days at initial pH values ranging from 2 to 5, to simulate potential real world conditions. At set times over the 600 day experiment, pH, oxidation reduction potential (ORP, dissolved oxygen and temperature were recorded and small liquid samples withdrawn and analysed for elemental concentrations using total reflection X-ray fluorescence spectrometry (TRXRF. Six of eight shale samples were found to be acid generating, with pH declining and ORP becoming increasingly positive after 100 days. Two of the eight shale samples produced increasingly alkaline leachate conditions with relatively low ORP after 100 days, indicating an inbuilt buffering capacity. By 600 days the buffering capacity of all samples had been consumed and all leachate samples were acidic. TRXRF analyses demonstrated significant potential for the leaching of S, Fe, Ni, Cu, Zn and Mn with greatest concentrations found in reaction vessels with most acidic pH and highest ORP.

  3. Population dynamics of Empetrum hermaphroditum (Ericaceae) on a subarctic sand dune: Evidence of rapid colonization through efficient sexual reproduction.

    Science.gov (United States)

    Boudreau, Stéphane; Ropars, Pascale; Harper, Karen Amanda

    2010-05-01

    The importance of sexual reproduction for clonal plant species has long been underestimated, perhaps as a consequence of the difficulty in identifying individuals, preventing the study of their population dynamics. Such is the case for Empetrum hermaphroditum, an ericaceous species, which dominates the ground vegetation of subarctic ecosystems. Despite abundant seed production, seedlings are rarely observed. Therefore, prevalent seedling recruitment on a subarctic dune system provided an opportunity to study the population dynamics and spatial pattern of the colonization phase of this species. We established a 6-ha grid on the dune systems that extended from the shoreline to the fixed dunes and mapped and measured all E. hermaphroditum individuals in the grid. Moreover, we sampled 112 individuals just outside the grid to identify any allometric relationship between the size and age of the individuals, which allowed us to reconstruct population expansion. The overall size structure suggests that the population is still expanding. In the last 50 yr, E. hermaphroditum advanced more than 200 m in the dune system. Expansion started in the 1960s simultaneously at different distances from the shoreline. Colonization did not proceed gradually from the fixed dune toward the shoreline but instead individuals established earlier in the troughs between the dunes, with an increasingly clumped spatial pattern as the population filled in with time.

  4. CO2 and CH4 in sea ice from a subarctic fjord under influence of riverine input

    DEFF Research Database (Denmark)

    Crabeck, O.; Delille, B.; Thomas, D. N.

    2014-01-01

    We present CH4 concentration [CH4] and the partial pressure of CO2 (pCO2) in bulk sea ice from subarctic, land-fast sea ice in the Kapisillit fjord, Greenland. The bulk ice [CH4] ranged from 1.8 to 12.1 nmol L−1, which corresponds to a partial pressure range of 3 to 28 ppmv. This is markedly higher...... than the average atmospheric methane content of 1.9 ppmv. Most of the trapped methane within the sea ice was evidently contained inside bubbles, and only a minor portion was dissolved in the brine. The bulk ice pCO2 ranged from 60 to 330 ppmv showing that sea ice at temperatures above −4 °C is under......-saturated compared to the atmosphere (390 ppmv). Our study adds to the few existing studies of CH4 and CO2 in sea ice and concludes that sub-arctic sea can be a sink for atmospheric CO2, while being a net source of CH4. Processes related to the freezing and melting of sea ice represents large unknowns...

  5. Comparison of aerosol optical properties at the sub-arctic stations ALOMAR-Andenes, Abisko and Sodankylä in late spring and summer 2007

    NARCIS (Netherlands)

    Rodríguez, E.; Toledano, C.; Cachorro, V.; Leeuw, G. de; Frutos, A.de; Gausa, M.; Holben, B.

    2012-01-01

    Aerosol concentration and aerosol type, retrieved from observations with CIMEL sun-photometers at three sub-arctic locations at the Scandinavian Peninsula are presented. The observations were made at ALOMAR-Andenes in Norway, Abisko in Sweden and Sodankylä in Finland. This field campaign took place

  6. Soil warming and fertilization altered rates of nitrogen transformation processes and selected for adapted ammonia-oxidizing archaea in sub-arctic grassland soil

    NARCIS (Netherlands)

    Daebeler, Anne; Bodelier, Paul L.E.; Hefting, Mariet M.; Rütting, Tobias; Laanbroek, Hendrikus J.

    Abstract The balance of microbial nitrogen (N) transformation processes in sub-arctic terrestrial ecosystems is most likely affected by global change, with potential feedbacks to greenhouse gas emissions and eutrophication. Soil temperature and N availability – their global increases being two of

  7. CMS Annual Report 2004

    Energy Technology Data Exchange (ETDEWEB)

    de la Rubia, T D; Shang, S P; Rennie, G; Fluss, M; Westbrook, C

    2005-07-29

    Glance at the articles in this report, and you will sense the transformation that is reshaping the landscape of materials science and chemistry. This transformation is bridging the gaps among chemistry, materials science, and biology--ushering in a wealth of innovative technologies with broad scientific impact. The emergence of this intersection is reinvigorating our strategic investment into areas that build on our strength of interdisciplinary science. It is at the intersection that we position our strategic vision into a future where we will provide radical materials innovations and solutions to our national-security programs and other sponsors. Our 2004 Annual Report describes how our successes and breakthroughs follow a path set forward by our strategic plan and four organizing research themes, each with key scientific accomplishments by our staff and collaborators. We have organized this report into two major sections: research themes and our dynamic teams. The research-theme sections focus on achievements arising from earlier investments while addressing future challenges. The dynamic teams section illustrates the directorate's organizational structure of divisions, centers, and institutes that support a team environment across disciplinary and institutional boundaries. The research presented in this annual report gives substantive examples of how we are proceeding in each of these four theme areas and how they are aligned with our national-security mission. By maintaining an organizational structure that offers an environment of collaborative problem-solving opportunities, we are able to nurture the discoveries and breakthroughs required for future successes.

  8. Hazards Control Department 1995 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, G.W.

    1996-09-19

    This annual report of the Hazards Control Department activities in 1995 is part of the department`s efforts to foster a working environment at Lawrence Livermore National Laboratory (LLNL) where every person desire to work safely.

  9. Tracking the origins of Yakutian horses and the genetic basis for their fast adaptation to subarctic environments

    DEFF Research Database (Denmark)

    Librado, Pablo; Der Sarkissian, Clio; Ermini, Luca

    2015-01-01

    , likely due to the comparatively limited standing variation within gene bodies at the time the population was founded. Genes involved in hair development, body size, and metabolic and hormone signaling pathways represent an essential part of the Yakutian horse adaptive genetic toolkit. Finally, we find......Yakutia, Sakha Republic, in the Siberian Far East, represents one of the coldest places on Earth, with winter record temperatures dropping below −70 °C. Nevertheless, Yakutian horses survive all year round in the open air due to striking phenotypic adaptations, including compact body conformations...

  10. Energy and Environment Division annual report, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Camp, J.A. (ed.)

    1978-01-01

    Research activities of this Division are reported under nine separate programs, namely: Energy Analysis; Solar Energy; Energy-Efficient Buildings; Chemical Process Research and Development; Environmental Research; Atmospheric Aerosol Research; Oil Shale Research; Instrumentation Development; and Combustion Research. A separate abstract was prepared for each of the nine programs, each of which contained several individual research summaries, with responsible researchers listed. All of the abstracts will appear in Energy Research Abstracts (ERA), and five will appear in Energy Abstracts for Policy Analysis (EAPA).

  11. Using 67Cu to study the biogeochemical cycling of copper in the northeast subarctic Pacific Ocean

    Directory of Open Access Journals (Sweden)

    David M Semeniuk

    2016-06-01

    Full Text Available Microbial copper (Cu nutrition and dissolved Cu speciation were surveyed along Line P, a coastal to open ocean transect that extends from the coast of British Columbia, Canada, to the high-nutrient-low-chlorophyll (HNLC zone of the northeast subarctic Pacific Ocean. Steady-state size fractionated Cu uptake rates and Cu:C assimilation ratios were determined at in situ Cu concentrations and speciation using a 67Cu tracer method. The cellular Cu:C ratios that we measured (~30 µmol Cu mol C-1 are similar to recent estimates using synchrotron x-ray fluorescence (SXRF, suggesting that the 67Cu method can determine in situ metabolic Cu demands. We examined how environmental changes along the Line P transect influenced Cu metabolism in the sub-microplankton community. Cellular Cu:C assimilation ratios and uptake rates were compared with net primary productivity, bacterial abundance and productivity, total dissolved Cu, Cu speciation, and a suite of other chemical and biological parameters. Total dissolved Cu concentrations ([Cu]d were within a narrow range (1.46 to 2.79 nM, and Cu was bound to a ~5-fold excess of strong ligands with conditional stability constants ( of ~1014. Free Cu2+ concentrations were low (pCu 14.4 to 15.1, and total and size fractionated net primary productivity (NPPV; µg C L-1 d-1 were negatively correlated with inorganic Cu concentrations ([Cu′]. We suggest this is due to greater Cu′ drawdown by faster growing phytoplankton populations. Using the relationship between [Cu′] drawdown and NPPV, we calculated a regional photosynthetic Cu:C drawdown export ratio between 1.5 and 15 µmol Cu mol C-1, and a mixed layer residence time (2.5 to 8 years that is similar to other independent estimates (2-12 years. Total particulate Cu uptake rates were between 22 and 125 times faster than estimates of Cu export; this is possibly mediated by rapid cellular Cu uptake and efflux by phytoplankton and bacteria or the effects of grazers and

  12. [Impact of industrial pollution on emission of carbon dioxide by soils in the Kola Subarctic Region].

    Science.gov (United States)

    Koptsik, G N; Kadulin, M S; Zakharova, A I

    2015-01-01

    Soil emission of carbon dioxide, the key component of carbon cycle and the characteristic of soil biological activity, has been studied in background and polluted ecosystems in the Kola subarctic, the large industrial region of Russia. Long-term air pollution by emissions of "Pechenganikel" smelter, the largest source of sulphur dioxide and heavy metals in Northern Europe, has caused the technogenic digression of forest ecosystems. As a result of the digression, the tree layer was destructed, the number of plant species was diminished, the activity of soil biota was weakened, the soils were polluted and exhausted, biogeochemical cycles of elements were disturbed and productivity of ecosystems shrunk. Field investigations revealed the decrease of the in.situ soil respiration in average from 190-230 mg C-CO2/m2 x per h in background pine forests to 130-160, 100, and 20 mg C-CO2/m2.per h at the stages of pine defoliation, sparse pine forest and technogenic barrens of the technogenic succession, respectively. The soil respira- tion in birch forests was more intense than in pine forests and tended to decrease from about 290 mg C-CO2/m2 x per h in background forests to 210-220 and 170-190 mg C-CO2/m2 x per h in defoliating forests and technogenic sparse forests, respectively. Due to high spatial variability of soil respiration in both pine and birch forests significant differences from the background level were found only in technogenic sparse forests and barrens. Soil respiration represents total production of carbon dioxide by plant roots and soil microorganisms. The decrease in share of root respiration in the total soil respiration with the rise of pollution from 38-57% in background forests up to zero in technogenic barrens has been revealed for the first time for this region. This indicates that plants seem to be more sensitive to pollution as compared to relatively resistant microorganisms. Soil respiration and the contribution of roots to the total respiration

  13. Quantifying landscape-level methane fluxes in subarctic Finland using a multiscale approach.

    Science.gov (United States)

    Hartley, Iain P; Hill, Timothy C; Wade, Thomas J; Clement, Robert J; Moncrieff, John B; Prieto-Blanco, Ana; Disney, Mathias I; Huntley, Brian; Williams, Mathew; Howden, Nicholas J K; Wookey, Philip A; Baxter, Robert

    2015-10-01

    Quantifying landscape-scale methane (CH4 ) fluxes from boreal and arctic regions, and determining how they are controlled, is critical for predicting the magnitude of any CH4 emission feedback to climate change. Furthermore, there remains uncertainty regarding the relative importance of small areas of strong methanogenic activity, vs. larger areas with net CH4 uptake, in controlling landscape-level fluxes. We measured CH4 fluxes from multiple microtopographical subunits (sedge-dominated lawns, interhummocks and hummocks) within an aapa mire in subarctic Finland, as well as in drier ecosystems present in the wider landscape, lichen heath and mountain birch forest. An intercomparison was carried out between fluxes measured using static chambers, up-scaled using a high-resolution landcover map derived from aerial photography and eddy covariance. Strong agreement was observed between the two methodologies, with emission rates greatest in lawns. CH4 fluxes from lawns were strongly related to seasonal fluctuations in temperature, but their floating nature meant that water-table depth was not a key factor in controlling CH4 release. In contrast, chamber measurements identified net CH4 uptake in birch forest soils. An intercomparison between the aerial photography and satellite remote sensing demonstrated that quantifying the distribution of the key CH4 emitting and consuming plant communities was possible from satellite, allowing fluxes to be scaled up to a 100 km(2) area. For the full growing season (May to October), ~ 1.1-1.4 g CH4  m(-2) was released across the 100 km(2) area. This was based on up-scaled lawn emissions of 1.2-1.5 g CH4  m(-2) , vs. an up-scaled uptake of 0.07-0.15 g CH4  m(-2) by the wider landscape. Given the strong temperature sensitivity of the dominant lawn fluxes, and the fact that lawns are unlikely to dry out, climate warming may substantially increase CH4 emissions in northern Finland, and in aapa mire regions in general. © 2015 The

  14. Paleo-iron supply to the Western Subarctic Pacific since the last glaciation

    Science.gov (United States)

    Lam, P. J.; Robinson, L. F.; Blusztajn, J.; McManus, J. F.; Cook, M. S.; Keigwin, L. D.

    2011-12-01

    A strong and pervasive productivity peak has been observed in cores around the North Pacific during the Bølling-Allerød warm period of the last deglaciation. Recently, it has been hypothesized that this peak may have been caused by an influx of iron from the continental shelves as they were flooded during the deglaciation (1). Here, we examine this hypothesis by reconstructing the flux and sources of detrital material to a sediment core from the Detroit seamount (Vinogradov 19/4 GGC-37, 50.4°N, 167.7°E, 3300m) in the Western Subarctic Pacific since the last glacial maximum (LGM), and compare to several proxies of paleo-productivity. We use 230Th-normalization to reconstruct the flux of biogenic and detrital material, and the neodymium and strontium isotopic compositions to distinguish between volcanic margin and continental loess sources of detrital material. We find that total detrital flux is highest during the last glacial maximum and early deglacial periods, a time of relatively low productivity, with approximately equal contributions from the volcanic margin and from continental loess. Total detrital flux starts to decline around 16kya, but increases again to 80% of the glacial maximum flux around the time of the Bølling-Allerød productivity peak. The local deglacial maximum in detrital flux coincides with a maximum in authigenic uranium, and immediately precedes maxima in opal flux, carbonate flux, benthic foraminifera abundance, and excess 231Pa/230Th. While the local deglacial maximum in detrital flux is consistent with iron stimulation of productivity, we conclude that iron supply alone is not sufficient to explain the deglacial productivity peak, since glacial times exhibited low productivity despite high detrital flux. Further, the relative and absolute contributions of detrital material of volcanic origin is lower during the deglaciation than during the LGM, suggesting that loess may have contributed more iron during the deglacial productivity

  15. Effects of Permafrost Thaw on Net Ecosystem Carbon Balance in a Subarctic Peatland

    Science.gov (United States)

    Wang, Z.; Roulet, N. T.; Moore, T. R.

    2014-12-01

    This research is to assess changes in net ecosystem carbon balance (NECB) with permafrost thaw in northern peatland: in particular how changes in C biogeochemistry influence NECB. Thawed transects associated with varying stages of permafrost thaw: from palsas with intact permafrost (P), through edge of palsa (EP), dry lawn (DL), wet lawn (WL), edge of thawed pond (ET), pond sedges (PS), to several thawed ponds (TP) in a subarctic peatland in northern Quebec were sampled in the snow free seasons of 2013 and 2014. The exchange of CO2 and CH4, vegetation, dissolved organic C (DOC) concentration and biodegradability, active layer depth, air and peat temperatures, water table depth (WT), pH, and conductivity were measured. Peat temperatures were quite similar among different locations, but the WT decreased significantly along the transect creating varied environmental conditions that supporting different plant communities. From dry to wet area, vegetation abundance and biomass showed reductions of shrubs and lichens, and increases of Sphagnum, grasses and sedges. Pore water pH increased from dry to wet area, and conductivity slightly decreased. Wet thaw area WL, ET and PS had relatively higher season gross ecosystem production (GEP) and higher season ecosystem respiration (ER), but relative similar net ecosystem CO2 exchange (NEE). Only TP had a significant higher positive season NEE. Palsa was the only CH4 sink, and quite high CH4 emissions were found after it thawed. CH4-C release significantly increased from dry to wet in thawed area, which even several times bigger than total C exchange in ET and PS. Generally, wet area had higher DOC concentration and higher DOC biodegradability indicated by lower SUVA254 (except PS which received great influence from pond). All components in the NECB (GEP, ER, CH4, DOC) increased significantly in magnitude from palsa to wet thawed area, and ecosystem C sink turned into source as palsa thawed into PS and TP. These results

  16. Reindeer grazing in subarctic boreal forest - influences on the soil carbon dynamics

    Science.gov (United States)

    Koster, Kajar; Berninger, Frank; Köster, Egle; Pumpanen, Jukka

    2015-04-01

    Reindeer (Rangifer tarandus L.) are the most important large mammalian herbivores in the northern ecosystems , which have many effects on plant diversity, soil nutrient cycling and soil organic matter decomposition. Changes caused by reindeer in vegetation have indirect effects on physical features of the soil e.g. soil microclimate, root biomass and also on soil C dynamics. Earlier, the role of reindeer grazing in ground vegetation dynamics and in soil carbon (C) dynamics has been mostly investigated in open tundra heaths. The objectives of this study were to examine if and how the reindeer grazing (and the possible temperature changes in soil caused by heavy grazing) is affecting the soil C dynamics (CO2 efflux from the soil, C storage in soil, microbial biomass in the soil). In a field experiment in Finnish Lapland, in Värriö Strict Nature Reserve (67° 46' N, 29° 35' E) we have assessed the changes occurring in above- and belowground biomasses, and soil C dynamics (CO2 efflux, soil C content, soil microbial biomass C) among areas grazed and ungrazed by reindeer. Our study areas are located in the northern boreal subarctic coniferous forest at the zone of the last intact forest landscapes in Fennoscandia, where large areas of relatively undisturbed subarctic Scots pine (Pinus sylvestris L.) forests can still be found. The sample plots located in the Värriö Strict Nature Reserve (10 sample plots in total established in year 2013) are situated along the borderline between Finland and Russia, where the ungrazed area was excluded from the reindeer grazing already in 1918, to prevent the Finnish reindeer from going to the Russian side and there are not many reindeer on Russian side of the area. To characterize the stands we have established circular sample plots on areas with a radius of 11.28 m, where different tree characteristics were measured (diameter at 1.3 m, height, height of a tree, crown height, crown diameter, stand age, etc.). On every sample plot

  17. Plant performance and soil nitrogen mineralization in response to simulation climate change in subarctic dwarf shrub heath

    Energy Technology Data Exchange (ETDEWEB)

    Hartley, A.E.; Neill, C.; Melillo, J.M.; Crabtree, R.; Bowles, F.P. [Marine Biological Lab., Ecosystems Center, Woods Hole, MA (United States)

    1999-08-01

    To simulate a future, warmer climate, we subjected subarctic dwarf shrub heath to 5 deg. C direct soil warming for five consecutive growing seasons (1993-1997). Supplemental air warming treatments vere imposed on warmed soil by plastic tents in 1994 and open-top chambers in 1995. Plant responses to warming were assessed by changes in: (1) shrub phenology. (2) current-year aboveground biomass in the dominant shrubs (Empetrum hermaphroditum, Vaccinium myrtillus, V. uliginosum and V. vitis-idaea), and (3) vascular and nonvascular plant cover. We estimated warming effects on soil nitrogen (N) availability by in situ buried bag incubation of soils. Soil warming stimulated soil N cycling and shrub growth and development in the short term (2-3 yr). In the second lear, net N mineralization rates doubled in warmed soil (4.3 kg N ha{sup -1} season{sup -1} in untreated soil vs 9.2 kg ha{sup -1} season{sup -1}). Greater N availability likely contributed to the observed 62% increase in current-year growth of V. myrtillus the dominant deciduous shrub. In the third year, soil and air warming increased shoot production by > 80% in the evergreen shrubs V. vitis-idaea and E. hermaphroditum. Soil warming had no detectable effects on plant growth or soil N cycling in the fifth year, suggesting that the long-term response may be less dramatic than short-term changes. Past fertilization studies in arctic and subarctic tundra reported an increase in the abundance of graminoids. Despite enhanced soil N mineralization in the second year we found that warming had little effect on plant community composition after five years. Even in an extreme climate warming scenario, it appears that subarctic soils mineralize an order of magnitude less N than was applied in fertilization experiments. High-dose fertilization studies provide insight into controls on plant communities, but do not accurately simulate increases in N availability predicted for a warmer climate. (au)

  18. Experimentally increased nutrient availability at the permafrost thaw front selectively enhances biomass production of deep-rooting subarctic peatland species.

    Science.gov (United States)

    Keuper, Frida; Dorrepaal, Ellen; van Bodegom, Peter M; van Logtestijn, Richard; Venhuizen, Gemma; van Hal, Jurgen; Aerts, Rien

    2017-10-01

    Climate warming increases nitrogen (N) mineralization in superficial soil layers (the dominant rooting zone) of subarctic peatlands. Thawing and subsequent mineralization of permafrost increases plant-available N around the thaw-front. Because plant production in these peatlands is N-limited, such changes may substantially affect net primary production and species composition. We aimed to identify the potential impact of increased N-availability due to permafrost thawing on subarctic peatland plant production and species performance, relative to the impact of increased N-availability in superficial organic layers. Therefore, we investigated whether plant roots are present at the thaw-front (45 cm depth) and whether N-uptake ((15) N-tracer) at the thaw-front occurs during maximum thaw-depth, coinciding with the end of the growing season. Moreover, we performed a unique 3-year belowground fertilization experiment with fully factorial combinations of deep- (thaw-front) and shallow-fertilization (10 cm depth) and controls. We found that certain species are present with roots at the thaw-front (Rubus chamaemorus) and have the capacity (R. chamaemorus, Eriophorum vaginatum) for N-uptake from the thaw-front between autumn and spring when aboveground tissue is largely senescent. In response to 3-year shallow-belowground fertilization (S) both shallow- (Empetrum hermaphroditum) and deep-rooting species increased aboveground biomass and N-content, but only deep-rooting species responded positively to enhanced nutrient supply at the thaw-front (D). Moreover, the effects of shallow-fertilization and thaw-front fertilization on aboveground biomass production of the deep-rooting species were similar in magnitude (S: 71%; D: 111% increase compared to control) and additive (S + D: 181% increase). Our results show that plant-available N released from thawing permafrost can form a thus far overlooked additional N-source for deep-rooting subarctic plant species and increase their

  19. Annual Energy Review 2005

    Energy Technology Data Exchange (ETDEWEB)

    Seiferlein, Katherine E. [USDOE Energy Information Administration (EIA), Washington, DC (United States)

    2006-07-01

    The Annual Energy Review (AER) is the Energy Information Administration's (EIA) primary report of annual historical energy statistics. For many series, data begin with the year 1949. Included are data on total energy production, consumption, and trade; overviews of petroleum, natural gas, coal, electricity, nuclear energy, renewable energy, international energy, as well as financial and environment indicators; and data unit conversion tables. Publication of this report is required under Public Law 95–91 (Department of Energy Organization Act), Section 205(c), and is in keeping with responsibilities given to the EIA under Section 205(a)(2), which states: “The Administrator shall be responsible for carrying out a central, comprehensive, and unified energy data and information program which will collect, evaluate, assemble, analyze, and disseminate data and information....” The AER is intended for use by Members of Congress, Federal and State agencies, energy analysts, and the general public. EIA welcomes suggestions from readers regarding data series in the AER and in other EIA publications.

  20. Annual Energy Review 2004

    Energy Technology Data Exchange (ETDEWEB)

    Seiferlein, Katherine E. [USDOE Energy Information Administration (EIA), Washington, DC (United States)

    2005-08-01

    The Annual Energy Review (AER) is the Energy Information Administration's (EIA) primary report of annual historical energy statistics. For many series, data begin with the year 1949. Included are data on total energy production, consumption, and trade; overviews of petroleum, natural gas, coal, electricity, nuclear energy, renewable energy, international energy, as well as financial and environment indicators; and data unit conversion tables. Publication of this report is required under Public Law 95–91 (Department of Energy Organization Act), Section 205(c), and is in keeping with responsibilities given to the EIA under Section 205(a)(2), which states: “The Administrator shall be responsible for carrying out a central, comprehensive, and unified energy data and information program which will collect, evaluate, assemble, analyze, and disseminate data and information....” The AER is intended for use by Members of Congress, Federal and State agencies energy analysts, and the general public. EIA welcomes suggestions from readers regarding data series in the AER and in other EIA publications.

  1. Annual Energy Review 2006

    Energy Technology Data Exchange (ETDEWEB)

    Seiferlein, Katherine E. [USDOE Energy Information Administration (EIA), Washington, DC (United States)

    2007-06-01

    The Annual Energy Review (AER) is the Energy Information Administration's (EIA) primary report of annual historical energy statistics. For many series, data begin with the year 1949. Included are data on total energy production, consumption, and trade; overviews of petroleum, natural gas, coal, electricity, nuclear energy, renewable energy, international energy, as well as financial and environment indicators; and data unit conversion tables. Publication of this report is required under Public Law 95–91 (Department of Energy Organization Act), Section 205(c), and is in keeping with responsibilities given to the EIA under Section 205(a)(2), which states: “The Administrator shall be responsible for carrying out a central, comprehensive, and unified energy data and information program which will collect, evaluate, assemble, analyze, and disseminate data and information....” The AER is intended for use by Members of Congress, Federal and State agencies, energy analysts, and the general public. EIA welcomes suggestions from readers regarding data series in the AER and in other EIA publications.

  2. Annual Energy Review 2009

    Energy Technology Data Exchange (ETDEWEB)

    Fichman, Barbara T. [USDOE Energy Information Administration (EIA), Washington, DC (United States)

    2010-08-01

    The Annual Energy Review (AER) is the U.S. Energy Information Administration's (EIA) primary report of annual historical energy statistics. For many series, data begin with the year 1949. Included are statistics on total energy production, consumption, trade, and energy prices; overviews of petroleum, natural gas, coal, electricity, nuclear energy, renewable energy, and international energy; financial and environment indicators; and data unit conversions. Publication of this report is required under Public Law 95–91 (Department of Energy Organization Act), Section 205(c), and is in keeping with responsibilities given to the EIA under Section 205(a)(2), which states: “The Administrator shall be responsible for carrying out a central, comprehensive, and unified energy data and information program which will collect, evaluate, assemble, analyze, and disseminate data and information....” The AER is intended for use by Members of Congress, Federal and State agencies, energy analysts, and the general public. EIA welcomes suggestions from readers regarding the content of the AER and other EIA publications.

  3. Annual Energy Review 2011

    Energy Technology Data Exchange (ETDEWEB)

    Fichman, Barbara T. [USDOE Energy Information Administration (EIA), Washington, DC (United States)

    2012-09-01

    The Annual Energy Review (AER) is the U.S. Energy Information Administration's (EIA) primary report of annual historical energy statistics. For many series, data begin with the year 1949. Included are statistics on total energy production, consumption, trade, and energy prices; overviews of petroleum, natural gas, coal, electricity, nuclear energy, and renewable energy; financial and environment indicators; and data unit conversions. Publication of this report is required under Public Law 95–91 (Department of Energy Organization Act), Section 205(c), and is in keeping with responsibilities given to the EIA under Section 205(a)(2), which states: “The Administrator shall be responsible for carrying out a central, comprehensive, and unified energy data and information program which will collect, evaluate, assemble, analyze, and disseminate data and information....” The AER is intended for use by Members of Congress, Federal and State agencies, energy analysts, and the general public. EIA welcomes suggestions from readers regarding the content of the AER and other EIA publications.

  4. Effects of litter addition and warming on soil carbon, nutrient pools and microbial communities in a subarctic heath ecosystem

    DEFF Research Database (Denmark)

    Rinnan, Riikka; Michelsen, Anders; Jonasson, Sven Evert

    2008-01-01

    Climatic warming leads to the expansion of deciduous shrubs and trees in the Arctic. This leads to higher leaf litter inputs, which together with warming may alter the rate of carbon and nutrient cycling in the arctic ecosystems. We assessed effects of factorial warming and additional litter...... on the soil ecosystem of a subarctic heath in a 7-year-long field experiment. Fine root biomass, dissolved organic carbon (DOC) and total C concentration increased in response to warming, which probably was a result of the increased vegetation cover. Litter addition increased the concentration of inorganic P...... in the uppermost 5 cm soil, while decreasing the pool of total P per unit area of the organic profile and having no significant effects on N concentrations or pools. Microbial biomass C and N were unaffected by the treatments, while the microbial biomass P increased significantly with litter addition. Soil...

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

    Directory of Open Access Journals (Sweden)

    Kashulina T. G.

    2016-03-01

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

  6. Climate change-induced vegetation change as a driver of increased subarctic biogenic volatile organic compound emissions

    DEFF Research Database (Denmark)

    Valolahti, Hanna Maritta; Kivimäenpää, Minna; Faubert, Patrick

    2015-01-01

    to a fixed temperature,warming still had a significant effect suggesting that emissions were also indirectly increased. This indirect increaseappeared to result from increased plant coverage and changes in vegetation composition. The litter addition treat-ment also caused significant increases in the emission...... and stimulated microbial production of BVOCs. We suggest that the changes in the subarcticvegetation composition induced by climate warming will be the major factor indirectly affecting the BVOC emissionpotentials and composition.......Emissions of biogenic volatile organic compounds (BVOCs) have been earlier shown to be highly temperature sensi-tive in subarctic ecosystems. As these ecosystems experience rapidly advancing pronounced climate warming, weaimed to investigate how warming affects the BVOC emissions in the long term...

  7. Phytoplankton growth and microzooplankton grazing along a sub-Arctic fjord (Godthåbsfjord, West Greenland)

    DEFF Research Database (Denmark)

    Calbet, A.; Riisgaard, Karen; Saiz, E.

    2011-01-01

    we established four zones: i) Fyllas Bank, characterized by deep chl a maxima (ca. 30-40 m) consisting of large cells; ii) the mouth and main branch of the fjord, where phytoplankton was relatively homogeneously distributed in the upper 30 m layer; iii) inner waters influenced by glacial melt water......We evaluated the role of microzooplankton (sensu latto, grazers Greenland subarctic fjord, Godthåbfjord. Based on the distribution of size fractionated chlorophyll a (chl a) concentrations...... the nutrient rich waters in the upwelling area in the vicinity of the glacier. Most of the grazing impact was on the 20 µm microzooplankton, as deducted from additional dilution experiments removing > 20 µm. Overall, little...

  8. Nitrogen Uptake During Fall, Winter and Spring Differs Among Plant Functional Groups in a Subarctic Heath Ecosystem

    DEFF Research Database (Denmark)

    Larsen, Klaus Steenberg; Michelsen, Anders; Jonasson, Sven

    2012-01-01

    Nitrogen (N) is a critical resource for plant growth in tundra ecosystems, and species differences in the timing of N uptake may be an important feature regulating community composition and ecosystem productivity. We added 15N-labelled glycine to a subarctic heath tundra dominated by dwarf shrubs......, mosses and graminoids in fall, and investigated its partitioning among ecosystem components at several time points (October, November, April, May, June) through to the following spring/early summer. Soil microbes had acquired 65 ± 7% of the 15N tracer by October, but this pool decreased through winter....... The faster-growing deciduous shrubs did not resume 15N acquisition until after early May indicating that they relied more on nitrogen made available later during the spring/early summer. The graminoids and mosses had no significant increases in 15N tracer recovery or tissue 15N tracer concentrations after...

  9. Improvement of state regulation of the agrarian sector of the sub-arctic and arctic areas under the WTO membership

    Directory of Open Access Journals (Sweden)

    Valentin Aleksandrovich Ivanov

    2015-01-01

    Full Text Available The article substantiates the necessity to change the role of the state in technological and socio-economic development of the agricultural sector. The author considers the forms and methods of state regulation and analyses the current budget support provided to agriculture; he highlights its drawbacks with regard to sub-arctic and arctic territories of the Republic of Komi. The article shows the influence of state support on the farmers’ level of income and identifies modernization risks and threats under Russia’s WTO membership. The author proposes measures to improve state support of the agrarian sector and change the adverse conditions of its functioning. He substantiates the approach that helps improve the state regulation of the agrarian sector in the framework of regional and municipal programs for rural development

  10. Effects of long-term warming and fertilisation on microarthropod abundances in three sub-arctic ecosystems

    DEFF Research Database (Denmark)

    Sjursen, Heidi; Michelsen, Anders; Jonasson, Sven Evert

    2005-01-01

    Soil microarthropod responses to long-term soil warming and increased fertilisation by addition of NKP or litter were assessed in three subarctic ecosystems. The experiment was carried out at three different field sites, where temperature and fertilisation manipulations had been running for 3...... had higher densities in the treatment with both fertilisation and warming. In the fellfield, we found increased densities of Oribatida, Gamasida and Actinedida in the fertilised treatments, and some increases in Oribatida and decreases in Collembola and Gamasida in warming treatments. In the heath......, there were increased densities of Collembola, Oribatida and Actinedida in the fertilised treatments, but we found no strong effects of warming. We suggest that the responses found in this study comply with the assumption that soil microarthropods are bottom-up controlled, and the observed changes...

  11. Mesoscale dynamics in the Lofoten Basin - a sub-Arctic "hot spot" of oceanic variability

    Science.gov (United States)

    Volkov, D. L.; Belonenko, T. V.; Foux, V. R.

    2012-12-01

    A sub-Arctic "hot spot" of intense mesoscale variability is observed in the Lofoten Basin (LB) - a topographic depression with a maximum depth of about 3250 m, located in the Norwegian Sea. The standard deviation of sea surface height (SSH), measured with satellite altimetry, reaches nearly 15 cm in the center of the basin (Figure 1a). Using a space-time lagged correlation analysis of altimetry data, we discover a cyclonic propagation of the mesoscale SSH anomalies around the center of the LB with time-averaged phase speeds of 2-4 km/day, strongly linked to bottom topography (Figure 1c). The fact that surface drifter trajectories do not exhibit cyclonic circulation in the LB (Figure 1b) suggests that, at least in the upper ocean, satellite altimetry observes only the propagation of form without the corresponding transfer of mass. Linearly propagating wavelike disturbances that do not trap fluid inside are related to planetary or Rossby waves. Variations in topography may lead to the concentration of wave energy in certain regions or wave trapping. The dispersion analysis suggests that the observed wavelike cyclonic propagation of SSH anomalies in the LB is the manifestation of baroclinic topographic Rossby waves, that we term "the basin waves" in order to distinguish them from the other types of topographic waves, such as shelf or trench waves. We identify two modes of basin waves in the LB: a di-pole mode and a quadri-pole mode. The wavelength of each mode is about 500 km. The frequency of these modes is not constant and the phase speed varies from about 2 to 8 km/day. We show that the cyclonically rotating basin waves are responsible for the observed amplification of SSH variability in the LB. Because the baroclinic basin waves in the LB are probably associated with large vertical displacements of the thermocline and due to possible wave breaking events, they can play an important role in the mixing of the inflowing Atlantic Water with ambient water masses

  12. Long-term addition of fertilizer, labile carbon, and fungicide alters the biomass of plant functional groups in a subarctic-alpine community

    DEFF Research Database (Denmark)

    Haugwitz-Hardenberg-Reventlow, M S; Michelsen, A.

    2011-01-01

    In subarctic ecosystems, plant growth is mostly limited by nutrient availability and harsh climate. Investigating how soil nutrient availability controls the plant community composition may therefore help to understand indirect effects of climate change. The study was conducted in a long-term field...... experiment on a subarctic-alpine fellfield dominated by woody evergreen shrubs, bryophytes, and lichens. To manipulate nutrient availability additions of NPK fertilizer, labile C, and fungicide (benomyl) were done in a fully factorial design, replicated in six blocks. The treatments were run for 10 years......, and the aboveground plant biomass was harvested 4 and 16 years after initiating the experiment. In addition, soil inorganic N and P concentration was analyzed the same years. Increased nutrient availability (NPK fertilizer) largely increased the biomass of graminoids and unexpectedly of bryophytes, but not of other...

  13. Annual report 1993-94

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    The annual report of the Ministry presents the activities of the Ministry`s departments: Corporate (public affairs and communications, employment equity, policy, planning and legislation, management services); BC Environment (environmental protection, fisheries, wildlife and habitat protection, environment regional operations); BC Lands (lands and water management, lands regional operations, lands services, water management); BC Parks (provincial parks, ecological reserves, outdoor recreation); Agencies, Boards, and Commissions (Commission on Waste Reduction, Soils, and Hazardous Wastes, Environmental Appeal Board); and Immigration and Multiculturalism (immigration policy, business immigration, multiculturalism BC, and BC Council of Human Rights). An organizational chart and financial overview are also included.

  14. We adapt … but is it good or bad? : Locating the political ecology and social-ecological systems debate in reindeer herding in the Swedish Sub-Arctic

    OpenAIRE

    Gallardo, Gloria; Saunders, Fred; Sokolova, Tatiana; Börebäck, Kristina; Laerhoven, Frank van; Kokko, Suvi; Tuvendal, Magnus

    2017-01-01

    Reindeer herding (RDH) is a livelihood strategy deeply connected to Sami cultural tradition. This article explores the implications of two theoretical and methodological approaches for grasping complex socioenvironmental relationships of RDH in Subarctic Sweden. Based on joint fieldwork, two teams – one that aligns itself with political ecology (PE) and the other with social-ecological systems (SES) – compared PE and SES approaches of understanding RDH. Our purpose was twofold: 1) to describe...

  15. Is there a negative impact of winter on mental distress and sleeping problems in the subarctic: The Tromsø Study

    Directory of Open Access Journals (Sweden)

    Johnsen May Trude

    2012-12-01

    Full Text Available Abstract Background Prior studies have suggested that the darkness of winter impacts the level of mental distress and sleeping problems. Our study investigated whether people living in the sub-arctic had more sleeping problems or mental distress during winter. Methods The cross sectional population Tromsø Study was conducted in Tromsø, North Norway, at 69.4 degrees North and above the Arctic Circle. The study included entire birth cohorts and random samples of the population aged 30 to 87 years. Data was collected continuously from 1 October 2007 to the end of December 2008 except July. 8951 persons completed questionnaires including the HSCL-10 and the MCTQ. Results There were no significant differences in the reporting of current mental distress depending on season. Significantly more reported current sleeping problems in winter than in the other seasons, and less sleeping problems was found in spring. Conclusions In this sub-arctic population, insomnia was most prevalent in winter, but there were no significant seasonal differences in mental distress. Although some people in the sub-arctic clearly are mentally negatively affected by the darkness of winter, the negative impact of winter on mental distress for the adult population is not conclusive.

  16. Hepatocyte responses to in vitro freezing and β-adrenergic stimulation: Insights into the extreme freeze tolerance of subarctic Rana sylvatica.

    Science.gov (United States)

    do Amaral, M Clara F; Lee, Richard E; Costanzo, Jon P

    2015-02-01

    The wood frog, Rana sylvatica LeConte 1825, is a freeze-tolerant amphibian widely distributed in North America. Subarctic populations of this species can survive experimental freezing to temperatures below -16 °C, whereas temperate populations tolerate freezing only at temperatures above -6 °C. We investigated whether hepatocytes isolated from frogs indigenous to Interior Alaska (subarctic) or southern Ohio (temperate) had distinct characteristics that could contribute to this variation in freeze tolerance capacity. Following in vitro freezing, cell damage, as assessed from lactate dehydrogenase leakage, was similar between samples from Alaskan and Ohioan frogs. Preincubation of cells in media containing glucose or urea, the two primary cryoprotectants used by R. sylvatica, markedly reduced freezing damage to hepatocytes; however, results suggested that cells of the northern phenotype were comparatively more amenable to cryoprotection by urea. Stimulation of isolated hepatocytes with β-adrenergic agonists, which simulates the freezing-induced cryoprotectant mobilization response, gave rates of glucose production from endogenous glycogen reserves that were similar between the populations. Our findings suggest that extreme freeze tolerance in subarctic R. sylvatica does not require an enhanced ability of the liver to resist freezing stress or rapidly mobilize cryoprotectant. © 2015 Wiley Periodicals, Inc.

  17. Oxygen and silicon stable isotopes of diatom silica. Reconstructing changes in surface water hydrography and silicic acid utilization in the late Pleistocene subarctic Pacific

    Energy Technology Data Exchange (ETDEWEB)

    Maier, Edith

    2014-03-05

    Deglacial variations in upper ocean nutrient dynamics and stratification in high latitudes, as well as associated changes in thermohaline overturning circulation, are thought to have played a key role in changing atmospheric CO{sub 2} concentrations. This thesis examines the relationship between past changes in subarctic Pacific upper ocean stratification and nutrient (silicic acid) utilization, using oxygen and silicon stable isotopes of diatom silica, for the first time at millennial-scale resolution and analyzed with a new and efficient instrumentation set-up. The isotopic data, presented in three manuscripts, show a consistent picture of millennial-scale variability in upper ocean stratification and silicic acid utilization during the last ∝50 ka BP, e.g. indicating that the subarctic Pacific was a source region for atmospheric CO{sub 2} during the last deglaciation (late Heinrich Stadial 1 and the Boelling/Alleroed). The presented results demonstrate the high potential of combined diatom oxygen and silicon stable isotope analysis especially for, but not restricted to, marine regions characterized by a low biogenic carbonate content like the subarctic Pacific and the Southern Ocean.

  18. Subpopulation structure of caribou (Rangifer tarandus L.) in arctic and subarctic Canada.

    Science.gov (United States)

    Nagy, John A; Johnson, Deborah L; Larter, Nicholas C; Campbell, Mitch W; Derocher, Andrew E; Kelly, Allicia; Dumond, Mathieu; Allaire, Danny; Croft, Bruno

    2011-09-01

    Effective management and conservation of species, subspecies, or ecotypes require an understanding of how populations are structured in space. We used satellite-tracking locations and hierarchical and fuzzy clustering to quantify subpopulations within the behaviorally different barren-ground caribou (Rangifer tarandus groenlandicus), Dolphin and Union island caribou (R. t. groenlandicus x pearyi), and boreal (R. t. caribou) caribou ecotypes in the Northwest Territories and Nunavut, Canada. Using a novel approach, we verified that the previously recognized Cape Bathurst, Bluenose-West, Bluenose-East, Bathurst, Beverly, Qamanirjuaq, and Lorillard barren-ground subpopulations were robust and that the Queen Maude Gulf and Wager Bay barren-ground subpopulations were organized as individuals. Dolphin and Union island and boreal caribou formed one and two distinct subpopulation, respectively, and were organized as individuals. Robust subpopulations were structured by strong annual spatial affiliation among females; subpopulations organized as individuals were structured by migratory connectivity, barriers to movement, and/or habitat discontinuity. One barren-ground subpopulation used two calving grounds, and one calving ground was used by two barren-ground subpopulations, indicating that these caribou cannot be reliably assigned to subpopulations solely by calving-ground use. They should be classified by annual spatial affiliation among females. Annual-range size and path lengths varied significantly among ecotypes, including mountain woodland caribou (R. t. caribou), and reflected behavioral differences. An east-west cline in annual-range sizes and path lengths among migratory barren-ground subpopulations likely reflected differences in subpopulation size and habitat conditions and further supported the subpopulation structure identified.

  19. Annual Check-up

    Science.gov (United States)

    ... Medical Conditions Nutrition & Fitness Emotional Health Annual Check-Up Posted under Health Guides . Updated 24 April 2017. + ... I get ready for my annual medical check-up? If this is your first visit to your ...

  20. Annual Energy Review 1999

    Energy Technology Data Exchange (ETDEWEB)

    Seiferlein, Katherine E. [USDOE Energy Information Administration (EIA), Washington, DC (United States)

    2000-07-01

    , to the end of the century? What happened to the relationship between growth and energy consumption? How did the fuel mix change over this period? What are the effects of energy usage on our environment? What level of consumption will the United States—and the world—record in the Annual Energy Review 2025? We present this edition of the Annual Energy Review to help investigate these important questions and to stimulate and inform our thinking about what the future holds.

  1. Comparison of snow melt properties across multiple spatial scales and landscape units in interior sub-Arctic boreal Alaskan watersheds

    Science.gov (United States)

    Bennett, K. E.; Cherry, J. E.; Hiemstra, C. A.; Bolton, W. R.

    2013-12-01

    Interior sub-Arctic Alaskan snow cover is rapidly changing and requires further study for correct parameterization in physically based models. This project undertook field studies during the 2013 snow melt season to capture snow depth, snow temperature profiles, and snow cover extent to compare with observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor at four different sites underlain by discontinuous permafrost. The 2013 melt season, which turned out to be the latest snow melt period on record, was monitored using manual field measurements (SWE, snow depth data collection), iButtons to record temperature of the snow pack, GoPro cameras to capture time lapse of the snow melt, and low level orthoimagery collected at ~1500 m using a Navion L17a plane mounted with a Nikon D3s camera. Sites were selected across a range of landscape conditions, including a north facing black spruce hill slope, a south facing birch forest, an open tundra site, and a high alpine meadow. Initial results from the adjacent north and south facing sites indicate a highly sensitive system where snow cover melts over just a few days, illustrating the importance of high resolution temporal data capture at these locations. Field observations, iButtons and GoPro cameras show that the MODIS data captures the melt conditions at the south and the north site with accuracy (2.5% and 6.5% snow cover fraction present on date of melt, respectively), but MODIS data for the north site is less variable around the melt period, owing to open conditions and sparse tree cover. However, due to the rapid melt rate trajectory, shifting the melt date estimate by a day results in a doubling of the snow cover fraction estimate observed by MODIS. This information can assist in approximating uncertainty associated with remote sensing data that is being used to populate hydrologic and snow models (the Sacramento Soil Moisture Accounting model, coupled with SNOW-17, and the Variable

  2. Sorting out non-sorted circles: Effects of winter climate change on the Collembola community of cryoturbated subarctic tundra

    Science.gov (United States)

    Krab, Eveline; Monteux, Sylvain; Becher, Marina; Blume-Werry, Gesche; Keuper, Frida; Klaminder, Jonatan; Kobayashi, Makoto; Lundin, Erik J.; Milbau, Ann; Roennefarth, Jonas; Teuber, Laurenz Michael; Weedon, James; Dorrepaal, Ellen

    2015-04-01

    Non-sorted circles (NSC) are a common type of cryoturbated (frost-disturbed) soil in the arctic and store large amounts of soil organic carbon (SOC) by the burial of organic matter. They appear as sparsely vegetated areas surrounded by denser tundra vegetation, creating patterned ground. Snowfall in the arctic is expected to increase, which will modify freezing intensity and freeze-thaw cycles in soils, thereby impacting on SOC dynamics. Vegetation, soil fauna and microorganisms, important drivers of carbon turnover, may benefit directly from the altered winter conditions and the resulting reduction in cryoturbation, but may also impact each other through trophic cascading. We investigated how Collembola, important decomposer soil fauna in high latitude ecosystems, are affected by increased winter insulation and vegetation cover. We subjected NSC in North-Swedish subarctic alpine tundra to two years of increased thermal insulation (snow fences or fiber cloth) in winter and spring, increasing soil temperatures and strongly reducing freeze-thaw frequency. From these NSC we sampled the Collembola community in: (i) the non-vegetated center, (ii) sparsely vegetated parts in the center and (iii) the vegetated domain surrounding NSC. To link changes in Collembola density and community composition to SOC dynamics, we included measurements of decomposer activity, dissolved organic carbon (DOC) and total extractable nitrogen (TN). We observed differences in Collembola density, community composition and soil fauna activity between the sampling points in the NSC. Specifically Collembola diversity increased with the presence of vegetation and density was higher in the vegetated outer domains. Increased winter insulation did not affect diversity but seemed to negatively affect density and decomposer activity in the vegetated outer domains. Interestingly, SOM distribution over NSC changed with snow addition (also to a lesser extent with fleece insulation) towards less SOM in the

  3. Elemental composition and optical properties reveal changes in dissolved organic matter along a permafrost thaw chronosequence in a subarctic peatland

    Energy Technology Data Exchange (ETDEWEB)

    Hodgkins, Suzanne; Tfaily, Malak M.; Podgorski, David C.; McCalley, Carmody; Saleska, Scott; Crill, Patrick M.; Rich, Virginia; Chanton, Jeffrey; Cooper, William T.

    2016-08-01

    The fate of carbon stored in permafrost-zone peatlands represents a significant uncertainty in global climate modeling. Given that the breakdown of dissolved organic matter (DOM) is often a major pathway for decomposition in peatlands, knowledge of DOM reactivity under different permafrost regimes is critical for determining future climate feedbacks. To explore the effects of permafrost thaw and resultant plant succession on DOM reactivity, we used a combination of Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), UV/Vis absorbance, and excitation-emission matrix spectroscopy (EEMS) to examine the DOM elemental composition and optical properties of 27 pore water samples gathered from various sites along a permafrost thaw sequence in Stordalen Mire, a thawing subarctic peatland in northern Sweden. The presence of dense Sphagnum moss, a feature that is dominant in the intermediate thaw stages, appeared to be the main driver of variation in DOM elemental composition and optical properties at Stordalen. Specifically, DOM from sites with Sphagnum had greater aromaticity, higher average molecular weights, and greater O/C, consistent with a higher abundance of phenolic compounds that likely inhibit decomposition. These compounds are released by Sphagnum and may accumulate due to inhibition of phenol oxidase activity by the acidic pH at these sites. In contrast, sites without Sphagnum, specifically fully-thawed rich fens, had more saturated, more reduced compounds, which were high in N and S. Optical properties at rich fens were indicated the presence of microbially-derived DOM, consistent with the higher decomposition rates previously measured at these sites. These results indicate that Sphagnum acts as an inhibitor of rapid decomposition and CH4 release in thawing subarctic peatlands, consistent with lower rates of CO2 and CH4 production previously observed at these sites. However, this inhibitory effect may disappear if Sphagnumdominated bogs

  4. Grazing by reindeer in subarctic coniferous forests - how it is affecting three main greenhouse gas emissions from soils.

    Science.gov (United States)

    Köster, Kajar; Köster, Egle; Berninger, Frank; Pumpanen, Jukka

    2017-04-01

    Reindeer (Rangifer tarandus L.) are the most important large mammalian herbivores in the northern ecosystems, strongly affecting Arctic lichen dominated ecosystems. Changes caused by reindeer in vegetation have indirect effects on physical features of the soil e.g. soil microclimate, root biomass and also on soil carbon dynamics, and little is known about reindeer and their impact on greenhouse gas (GHG) emissions between the soil and atmosphere. In a field experiment in northern boreal subarctic coniferous forests in Finnish Lapland, we investigated the influence of reindeer grazing on soil GHG (CO2, CH4 and N2O) fluxes, ground vegetation coverage and biomass, soil temperature and water content. The study was carried out in the growing season of the year 2014. We established the experiment as a split plot experiment with 2 blocks and 5 sub-plots per treatment that were divided into grazed and non-grazed parts, separated with a fence. The sample plots are located along the borderline between Finland and Russia, where the non-grazed area was excluded from reindeer already in 1918, to prevent the Finnish reindeer from going to the Russian side and there are not many reindeer on Russian side of the area. Our study showed that grazing by reindeer significantly affected lichen and moss biomasses. Lichen biomass was significantly lower in the grazed. We also observed that when lichens were removed, mosses were quickly overtaking the areas and moss biomass was significantly higher in grazed areas compared to non-grazed areas. Our results indicated that grazing by reindeer in the northern boreal subarctic forests affects the GHG emissions from the forest floor and these emissions largely depend on changes in vegetation composition. Soil was always a source of CO2in our study, and soil CO2 emissions were significantly smaller in non-grazed areas compared to grazed areas. The soils in our study areas were CH4 sinks through entire measurement period, and grazed areas consumed

  5. Sustainable Agriculture and Climate Change: Producing Potatoes (Solanum tuberosum L. and Bush Beans (Phaseolus vulgaris L. for Improved Food Security and Resilience in a Canadian Subarctic First Nations Community

    Directory of Open Access Journals (Sweden)

    Christine D. Barbeau

    2015-05-01

    Full Text Available Aboriginal people in Canada experience disproportionately high rates of diet-related illnesses, such as obesity and diabetes. Food insecurity has been identified as a contributing factor to these illnesses along with a loss of traditional lifestyle. Current food systems within northern subarctic and arctic regions of Canada rely heavily on imported foods that are expensive (when available, and are environmentally unsustainable. A warming subarctic and arctic climate present challenges, but also offers the opportunity for local agricultural production that can increase food security and promote a more sustainable food system. In this study the feasibility of sustainably growing potatoes (Solanum tuberosum L. utilizing agroforestry practices to enhance food security in remote subarctic communities is explored through a case study in Fort Albany First Nation in northern Ontario, Canada. Potato crops were grown over a two-year period and rotated into plots that had been planted with green bush beans (Phaseolus vulgaris L.. Results showed that potatoes and bush beans could be grown successfully in the subarctic without the use of greenhouses with yields comparable to more conventional high-input agricultural methods. In subarctic Canada, sustainable local food production can help to promote social capital, healthier lifestyles, and food security.

  6. Diurnal and seasonal variations of pH for a year in the western subarctic North Pacific observed by using a hybrid pH sensor

    Science.gov (United States)

    Nakano, Yoshiyuki; Fujiki, Tetsuichi; Kimoto, Katsunori; Miwa, Tetsuya

    2017-04-01

    Ocean acidification has many far reaching impacts on plankton community in the ocean. There is great need of quality instrumentation to assess and monitor the changing seawater pH. To meet the need, we have developed the in situ high accurate pH sensor (Hybrid pH sensor: HpHS) for the long-term seawater pH monitoring to participate the Wendy Schmidt Ocean health XPRIZE. The HpHS has two types of pH sensors (i.e. potentiometric pH sensor and spectrophotometric pH sensor). The spectrophotometric pH sensor can measure pH correctly and stably, however it needs large power consumption and a lot of reagents in a long period of observation. The pH sensor used m-cresol purple (mCP) as an indicator of pH. On the other hand, although the potentiometric pH sensor is low power consumption and high-speed response (within 10 seconds), drifts in the pH of the potentiometric measurements may possibly occur for a long-term observation. The HpHS can measure in situ pH correctly and stably combining advantage of both pH sensors. The HpHS is correcting the value of the potentiometric pH (measuring frequently) by the value of the spectrophotometric pH (measuring less frequently). It is possible to calibrate in situ with Tris buffer or CRM on the spectrophotometric pH sensor. Therefore, the drifts in the value of potentiometric pH measurements can be compensated using the pH value obtained from the spectrophotometric pH measurements. Thereby, the HpHS can measure accurately the value of pH over a long period of time with low power consumption. In order to understand the seasonal and inter-annual variabilities of biogeochemical cycles and ecosystems, ship-based studies have been carried out since 1997 at time-series station K2 (47oN, 160oE) in the subarctic western North Pacific, which is a region with progression of ocean acidification. However, the ship-based studies of the open ocean have been limited in their ability to conduct high-frequency observations for understanding the

  7. Secretary's annual report to Congress

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-01-01

    This second annual report of the DOE covers activities of all elements of the department except the independent FERC, which issues its own annual report. Individual chapters concern a posture statement, conservation, solar and other renewable energy, fossil energy, electric energy, nuclear energy, the environment, defense programs, international programs, general science programs, energy information, economic regulation, energy production, and support operations. The following appendixes are also included: foreign direct investments in US energy sources and supplies, exports of energy resources by foreign companies, major recipients of DOE funding, actions taken regarding disclosure of energy assets by DOE employees, financial assistance programs for alternative fuel demonstration facilities, and 1978 budget summary. 16 figures, 56 tables. (RWR)

  8. 2014 HPC Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    Jennings, Barbara [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-10-01

    Our commitment is to support you through delivery of an IT environment that provides mission value by transforming the way you use, protect, and access information. We approach this through technical innovation, risk management, and relationships with our workforce, Laboratories leadership, and policy makers nationwide. This second edition of our HPC Annual Report continues our commitment to communicate the details and impact of Sandia’s large-scale computing resources that support the programs associated with our diverse mission areas. A key tenet to our approach is to work with our mission partners to understand and anticipate their requirements and formulate an investment strategy that is aligned with those Laboratories priorities. In doing this, our investments include not only expanding the resources available for scientific computing and modeling and simulation, but also acquiring large-scale systems for data analytics, cloud computing, and Emulytics. We are also investigating new computer architectures in our advanced systems test bed to guide future platform designs and prepare for changes in our code development models. Our initial investments in large-scale institutional platforms that are optimized for Informatics and Emulytics work are serving a diverse customer base. We anticipate continued growth and expansion of these resources in the coming years as the use of these analytic techniques expands across our mission space. If your program could benefit from an investment in innovative systems, please work through your Program Management Unit ’s Mission Computing Council representatives to engage our teams.

  9. Community- and population-level changes in diatom size structure in a subarctic lake over the last two centuries

    Directory of Open Access Journals (Sweden)

    Elizabeth A. Kerrigan

    2015-07-01

    Full Text Available Climate change over the last two centuries has been associated with significant shifts in diatom community structure in lakes from the high arctic to temperate latitudes. To test the hypotheses that recent climate warming selects for species of smaller size within communities and a decrease in the average size of species within populations, we quantified the size of individual diatom valves from 10 depths in a sediment core covering the last ∼200 years from a pristine subarctic lake. Over the last ∼200 years, changes in the relative abundance of species of different average size and changes in the average valve size of populations of species contribute equally to the changes in community size structure, but are often opposite in sign, compensating for one another and moderating temporal changes in community size structure. In the surface sediments that correspond to the recent decades when air temperatures have warmed, the mean size of valves in the diatom community has significantly decreased due to an increase in the proportion of smaller-sized planktonic diatom species.

  10. High Methylmercury in Arctic and Subarctic Ponds is Related to Nutrient Levels in the Warming Eastern Canadian Arctic.

    Science.gov (United States)

    MacMillan, Gwyneth A; Girard, Catherine; Chételat, John; Laurion, Isabelle; Amyot, Marc

    2015-07-07

    Permafrost thaw ponds are ubiquitous in the eastern Canadian Arctic, yet little information exists on their potential as sources of methylmercury (MeHg) to freshwaters. They are microbially active and conducive to methylation of inorganic mercury, and are also affected by Arctic warming. This multiyear study investigated thaw ponds in a discontinuous permafrost region in the Subarctic taiga (Kuujjuarapik-Whapmagoostui, QC) and a continuous permafrost region in the Arctic tundra (Bylot Island, NU). MeHg concentrations in thaw ponds were well above levels measured in most freshwater ecosystems in the Canadian Arctic (>0.1 ng L(-1)). On Bylot, ice-wedge trough ponds showed significantly higher MeHg (0.3-2.2 ng L(-1)) than polygonal ponds (0.1-0.3 ng L(-1)) or lakes (ponds near Kuujjuarapik (0.1-3.1 ng L(-1)). High water MeHg concentrations in thaw ponds were strongly correlated with variables associated with high inputs of organic matter (DOC, a320, Fe), nutrients (TP, TN), and microbial activity (dissolved CO2 and CH4). Thawing permafrost due to Arctic warming will continue to release nutrients and organic carbon into these systems and increase ponding in some regions, likely stimulating higher water concentrations of MeHg. Greater hydrological connectivity from permafrost thawing may potentially increase transport of MeHg from thaw ponds to neighboring aquatic ecosystems.

  11. Trends in Ostracoda and Cladocera distribution and water chemistry in subarctic Canada: Churchill (Manitoba lakes and ponds revisited

    Directory of Open Access Journals (Sweden)

    Finn A. Viehberg

    2017-03-01

    Full Text Available Ponds and lakes distributed across northern treeline in the Hudson Bay Lowlands near Churchill (Manitoba were revisited to analyse and document the local ecoclimatic and limnological changes that occurred over the period 1997-2012. Our analyses revealed that single events may cause significant changes in salinity, pH and silicate content because of the limited buffer capacity of the inter-connected waters. Planktic freshwater microcrustaceans (Cladocera presented less diverse assemblages and appeared to favour waters that are situated in the boreal forest, while the diversity of benthic species assemblages (Cladocera and Ostracoda was highest in waters located closer to the coastline and in open tundra vegetation. We identified three species that are distinctive for the boreal ecozone (i.e., Candona acuta, Can. acutula and Can. decora and two species (i.e., Tonnacypris glacialis and Can. rawsoni that are elements of (sub-arctic landscapes and potentially endangered as the northern treeline expands due to rapid warming. These species are thought to be useful indicators for future ecosystem quality assessments and/or ecosystem service management programs. Our findings were compared to other studies completed in the boreal Yukon Territory and revealed that species diversity is closely linked to landscape history.

  12. Dynamic controls on the subarctic North Pacific productivity peak during the Bølling-Allerød

    Science.gov (United States)

    Gong, Xun; Lembke-Jene, Lester; Tiedemann, Ralf; Lohmann, Gerrit

    2016-04-01

    Prominent maxima of biological productivity are recorded in both the Northwest and Northeast Pacific during the deglacial, interstadial Bølling-Allerød. These have been linked to a suite of differing causes and mechanisms, such as preservation effects, iron fertilization, riverine fluxes, upper ocean stratification and coastal upwelling. There is also widespread evidence for shifts in the subarctic Pacific ocean circulation during the deglaciation. However, while the dynamics of nutrient provision and limitation within the photic zone are certainly of high significance, the important role of physical circulation changes in the subsurface to deep ocean in replenishing nutrient supplies to the upper ocean, and of upper ocean temperature changes in fostering productivity peaks, remain largely unconstrained over the course of the last deglaciation. Here, using an Earth System Model COSMOS, we conducted a simulation representing the climate transition from the Last Glacial Maximum to the Bølling-Allerød. In association with marine proxy evidence, we will discuss the deglacial evolution of the surface to deep ocean circulation and mixing in the North Pacific, and examine their respective roles in determining the upwelling of nutrients from deeper layers, along with the formation of the North Pacific Intermediate water.

  13. Environmental factors influencing soil testate amoebae in herbaceous and shrubby vegetation along an altitudinal gradient in subarctic tundra (Abisko, Sweden).

    Science.gov (United States)

    Tsyganov, Andrey N; Milbau, Ann; Beyens, Louis

    2013-05-01

    Shifts in community composition of soil protozoa in response to climate change may substantially influence microbial activity and thereby decomposition processes. However, effects of climate and vegetation on soil protozoa remain poorly understood. We studied the distribution of soil testate amoebae in herbaceous and shrubby vegetation along an altitudinal gradient (from below the treeline at 500 m to the mid-alpine region at 900 m a.s.l.) in subarctic tundra. To explain patterns in abundance, species diversity and assemblage composition of testate amoebae, a data set of microclimate and soil chemical characteristics was collected. Both elevation and vegetation influenced the assemblage composition of testate amoebae. The variation was regulated by interactive effects of summer soil moisture, winter soil temperature, soil pH and nitrate ion concentrations. Besides, soil moisture regulated non-linear patterns in species richness across the gradient. This is the first study showing the effects of winter soil temperatures on species composition of soil protozoa. The effects could be explained by specific adaptations of testate amoebae such as frost-resistant cysts allowing them to survive low winter temperatures. We conclude that the microclimate and soil chemical characteristics are the main drivers of changes in protozoan assemblage composition in response to elevation and vegetation. Copyright © 2012 Elsevier GmbH. All rights reserved.

  14. Topsoil pollution forecasting using artificial neural networks on the example of the abnormally distributed heavy metal at Russian subarctic

    Science.gov (United States)

    Tarasov, D. A.; Buevich, A. G.; Sergeev, A. P.; Shichkin, A. V.; Baglaeva, E. M.

    2017-06-01

    Forecasting the soil pollution is a considerable field of study in the light of the general concern of environmental protection issues. Due to the variation of content and spatial heterogeneity of pollutants distribution at urban areas, the conventional spatial interpolation models implemented in many GIS packages mostly cannot provide appreciate interpolation accuracy. Moreover, the problem of prediction the distribution of the element with high variability in the concentration at the study site is particularly difficult. The work presents two neural networks models forecasting a spatial content of the abnormally distributed soil pollutant (Cr) at a particular location of the subarctic Novy Urengoy, Russia. A method of generalized regression neural network (GRNN) was compared to a common multilayer perceptron (MLP) model. The proposed techniques have been built, implemented and tested using ArcGIS and MATLAB. To verify the models performances, 150 scattered input data points (pollutant concentrations) have been selected from 8.5 km2 area and then split into independent training data set (105 points) and validation data set (45 points). The training data set was generated for the interpolation using ordinary kriging while the validation data set was used to test their accuracies. The networks structures have been chosen during a computer simulation based on the minimization of the RMSE. The predictive accuracy of both models was confirmed to be significantly higher than those achieved by the geostatistical approach (kriging). It is shown that MLP could achieve better accuracy than both kriging and even GRNN for interpolating surfaces.

  15. Effects of reindeer on the re-establishment of Betula pubescens subsp. czerepanovii and Salix phylicifolia in a subarctic meadow

    Directory of Open Access Journals (Sweden)

    Michael den Herder

    2003-04-01

    Full Text Available The effect of reindeer browsing on the regeneration of Betula pubescens subsp. czerepanovii and Salix phylicifolia was studied in a subarctic meadow in Finnish Lapland. The aim of the study was to see whether tree recovery from seeds is possible under heavy reindeer-browsing pressure. After removal of the ground and field layer vegetation in 1986, two exclosures were established so that the effect of reindeer on the secondary succession, starting from seeds, could be studied. The size and the number of B. pubescens and S. phylicifolia were recorded in 1994, 1996, 1997 and 1999. Reindeer significantly reduced the height and the number of saplings (plants > 10 cm high of B. pubescens and S. phylicifolia but the number of seedlings (plants < 10 cm high did not differ between browsed and unbrowsed plots. Furthermore the heightclass distribution of saplings was different inside the exlosures compared to control areas. Over time browsed plots continued to have high densities of small saplings while in protected plots an increasing number of larger saplings appeared. In our study site, regeneration from seeds seemed possible although the height of B. pubescens and S. phylicifolia was limited by reindeer. 

  16. Seasonal and interannual phytoplankton production in a sub-arctic tidewater outlet glacier fjord, west Greenland

    DEFF Research Database (Denmark)

    Juul-Pedersen, T.; Arendt, K.; Mortensen, J.

    2015-01-01

    This study describes seasonal patterns and proposes likely drivers of an unusual phytoplankton primary production pattern in the outer-sill region of a tidewater outlet glacierinfluenced fjord (Godthåbsfjord) in SW Greenland. It is based on monthly measurements of pelagic primary production...... and hydrographic conditions during a 7 yr period. Total annual primary production during 2005 to 2012 was between 84.6 and 139.1 g C m−2 yr−1. Two phytoplankton blooms of similar magnitude reoccur in the fjord every year. A ‘classical’ spring bloom of up to 1743 mg C m−2 d−1 occurred in late April/early May...... the Greenland Ice Sheet are thus likely to affect phytoplankton dynamics in the fjord....

  17. Annual Statistical Supplement, 2002

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2002 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  18. Annual Statistical Supplement, 2003

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2003 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  19. Annual Statistical Supplement, 2001

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2001 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  20. Annual Statistical Supplement, 2010

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2010 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  1. Annual Statistical Supplement, 2007

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2007 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  2. Annual Statistical Supplement, 2016

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2016 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  3. Annual Statistical Supplement, 2000

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2000 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  4. Annual Statistical Supplement, 2008

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2008 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  5. Annual Statistical Supplement, 2006

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2006 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  6. Annual Statistical Supplement, 2005

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2005 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  7. Annual Statistical Supplement, 2015

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2015 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  8. Annual Statistical Supplement, 2004

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2004 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  9. Annual Statistical Supplement, 2014

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2014 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  10. Annual Statistical Supplement, 2009

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2009 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  11. Annual Statistical Supplement, 2011

    Data.gov (United States)

    Social Security Administration — The Annual Statistical Supplement, 2011 includes the most comprehensive data available on the Social Security and Supplemental Security Income programs. More than...

  12. 2011 ANNUAL SITE ENVIRONMENTAL REPORT

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, A.; Eddy, T.; Jannik, T.; Terry, B.; Cauthen, K.; Coward, L.; Dunaway-Ackerman, J.; Wilson, M.; Hutchison, J.; O' Quinn, S.

    2012-10-01

    The Savannah River Site Environmental Report for 2011 (SRNS-STI-2012-00200) is prepared for the U.S. Department of Energy (DOE) according to requirements of DOE Order 231.1 B, “Environment, Safety and Health Reporting." The annual SRS Environmental Report has been produced for more than 50 years. Several hundred copies are and interested individuals. The report’s purpose is to: present summary environmental data that characterize site environmental management performance; describe compliance status with respect to environmental standards and requirements; highlight significant programs and efforts.

  13. Climatology of sediment flux and composition in the subarctic Northeast Pacific Ocean with biogeochemical implications

    Science.gov (United States)

    Timothy, D. A.; Wong, C. S.; Barwell-Clarke, J. E.; Page, J. S.; White, L. A.; Macdonald, R. W.

    2013-09-01

    Sequentially sampling conical sediment traps were maintained at Ocean Station Papa (OSP; 50°N, 145°W) in the Alaska Gyre from September 1982 to June 2006. The time series began with a single trap at 3800 m and traps were added at 1000 m and 200 m in March 1983 and May 1989, respectively. A trap at 3500-3700 m also was moored 5° north of OSP from May 1990 to August 1992. Total mass, biogenic silica (BSi), calcium carbonate (CaCO3), particulate organic carbon (POC) and particulate nitrogen (PN) were routinely measured. In this paper, we develop climatologies of sediment flux and composition at OSP, describing the characteristic features for comparison to sedimentary conditions globally. We then expand our use of the climatologies to arrive at four main conclusions regarding ecology and geochemistry at OSP. Fluxes of BSi and CaCO3 at 200 m and 1000 m lag by one month the annual cycle of irradiance and arrive at 3800 m ∼16 d later, with maximum export occurring several months later for POC. Next, the annual cycle of BSi flux shows that diatom production in late winter and spring is higher than indicated by spring decline of surface nutrients. We then show that the annual cycle of POC flux implies a net community production of organic carbon (NCPOC) of 3.6-5.3 mol m-2 y-1, double estimates based on mixed layer tracers but similar to estimates unaffected by mixing. NCPOC, combined with a CaCO3:POC production ratio of 0.18 determined from trap fluxes, gives a net community production of CaCO3 (NCPIC) of 0.65-0.95 mol m-2 y-1, in agreement with CaCO3 dissolution in the water column plus abyssal CaCO3 flux. Lastly, the flux climatologies at 1000 m and 3800 m are used to infer particle transformations in the bathypelagic zone including disaggregation and remineralization. Fluxes at 3800 m are best described as the sum of a primary flux sinking rapidly and a slowly-sinking secondary flux. Disaggregation of the primary flux is the likely source of secondary fluxes, with a

  14. Climatic and biotic extreme events moderate long-term responses of above- and belowground sub-Arctic heathland communities to climate change.

    Science.gov (United States)

    Bokhorst, Stef; Phoenix, Gareth K; Berg, Matty P; Callaghan, Terry V; Kirby-Lambert, Christopher; Bjerke, Jarle W

    2015-11-01

    Climate change impacts are not uniform across the Arctic region because interacting factors causes large variations in local ecosystem change. Extreme climatic events and population cycles of herbivores occur simultaneously against a background of gradual climate warming trends and can redirect ecosystem change along routes that are difficult to predict. Here, we present the results from sub-Arctic heath vegetation and its belowground micro-arthropod community in response to the two main drivers of vegetation damage in this region: extreme winter warming events and subsequent outbreaks of the defoliating autumnal moth caterpillar (Epirrita autumnata). Evergreen dwarf shrub biomass decreased (30%) following extreme winter warming events and again by moth caterpillar grazing. Deciduous shrubs that were previously exposed to an extreme winter warming event were not affected by the moth caterpillar grazing, while those that were not exposed to warming events (control plots) showed reduced (23%) biomass from grazing. Cryptogam cover increased irrespective of grazing or winter warming events. Micro-arthropods declined (46%) following winter warming but did not respond to changes in plant community. Extreme winter warming and caterpillar grazing suppressed the CO2 fluxes of the ecosystem. Evergreen dwarf shrubs are disadvantaged in a future sub-Arctic with more stochastic climatic and biotic events. Given that summer warming may further benefit deciduous over evergreen shrubs, event and trend climate change may both act against evergreen shrubs and the ecosystem functions they provide. This is of particular concern given that Arctic heath vegetation is typically dominated by evergreen shrubs. Other components of the vegetation showed variable responses to abiotic and biotic events, and their interaction indicates that sub-Arctic vegetation response to multiple pressures is not easy to predict from single-factor responses. Therefore, while biotic and climatic events may

  15. What determines the current presence or absence of permafrost in the Torneträsk region, a sub-arctic landscape in northern Sweden?

    Science.gov (United States)

    Johansson, Margareta; Christensen, Torben R; Akerman, H Jonas; Callaghan, Terry V

    2006-06-01

    In a warming climate, permafrost is likely to be significantly reduced and eventually disappear from the sub-Arctic region. This will affect people at a range of scales, from locally by slumping of buildings and roads, to globally as melting of permafrost will most likely increase the emissions of the powerful greenhouse gas methane, which will further enhance global warming. In order to predict future changes in permafrost, it is crucial to understand what determines the presence or absence of permafrost under current climate conditions, to assess where permafrost is particularly vulnerable to climate change, and to identify where changes are already occurring. The Torneträsk region of northern sub-Arctic Sweden is one area where changes in permafrost have been recorded and where permafrost could be particularly vulnerable to any future climate changes. This paper therefore reviews the various physical, biological, and anthropogenic parameters that determine the presence or absence of permafrost in the Torneträsk region under current climate conditions, so that we can gain an understanding of its current vulnerability and potential future responses to climate change. A patchy permafrost distribution as found in the Torneträsk region is not random, but a consequence of site-specific factors that control the microclimate and hence the surface and subsurface temperature. It is also a product of past as well as current processes. In sub-Arctic areas such as northern Sweden, it is mainly the physical parameters, e.g., topography, soil type, and climate (in particular snow depth), that determine permafrost distribution. Even though humans have been present in the study area for centuries, their impacts on permafrost distribution can more or less be neglected at the catchment level. Because ongoing climate warming is projected to continue and lead to an increased snow cover, the permafrost in the region will most likely disappear within decades, at least at lower

  16. Relative importance of plant uptake and plant associated denitrification for removal of nitrogen from mine drainage in sub-arctic wetlands.

    Science.gov (United States)

    Hallin, Sara; Hellman, Maria; Choudhury, Maidul I; Ecke, Frauke

    2015-11-15

    Reactive nitrogen (N) species released from undetonated ammonium-nitrate based explosives used in mining or other blasting operations are an emerging environmental problem. Wetlands are frequently used to treat N-contaminated water in temperate climate, but knowledge on plant-microbial interactions and treatment potential in sub-arctic wetlands is limited. Here, we compare the relative importance of plant uptake and denitrification among five plant species commonly occurring in sub-arctic wetlands for removal of N in nitrate-rich mine drainage in northern Sweden. Nitrogen uptake and plant associated potential denitrification activity and genetic potential for denitrification based on quantitative PCR of the denitrification genes nirS, nirK, nosZI and nosZII were determined in plants growing both in situ and cultivated in a growth chamber. The growth chamber and in situ studies generated similar results, suggesting high relevance and applicability of results from growth chamber experiments. We identified denitrification as the dominating pathway for N-removal and abundances of denitrification genes were strong indicators of plant associated denitrification activity. The magnitude and direction of the effect differed among the plant species, with the aquatic moss Drepanocladus fluitans showing exceptionally high ratios between denitrification and uptake rates, compared to the other species. However, to acquire realistic estimates of N-removal potential of specific wetlands and their associated plant species, the total plant biomass needs to be considered. The species-specific plant N-uptake and abundance of denitrification genes on the root or plant surfaces were affected by the presence of other plant species, which show that both multi- and inter-trophic interactions are occurring. Future studies on N-removal potential of wetland plant species should consider how to best exploit these interactions in sub-arctic wetlands. Copyright © 2015 Elsevier Ltd. All rights

  17. Importance of Ekman transport and gyre circulation change on seasonal variation of surface dissolved iron in the western subarctic North Pacific

    Science.gov (United States)

    Nakanowatari, Takuya; Nakamura, Tomohiro; Uchimoto, Keisuke; Nishioka, Jun; Mitsudera, Humio; Wakatsuchi, Masaaki

    2017-05-01

    Iron (Fe) is an essential nutrient for marine phytoplankton and it constitutes an important element in the marine carbon cycle in the ocean. This study examined the mechanisms controlling seasonal variation of dissolved Fe (dFe) in the western subarctic North Pacific (WSNP), using an ocean general circulation model coupled with a simple biogeochemical model incorporating a dFe cycle fed by two major sources (atmospheric dust and continental shelf sediment). The model reproduced the seasonal cycle of observed concentrations of dFe and macronutrients at the surface in the Oyashio region with maxima in winter (February-March) and minima in summer (July-September), although the simulated seasonal amplitudes are a half of the observed values. Analysis of the mixed-layer dFe budget indicated that both local vertical entrainment and lateral advection are primary contributors to the wintertime increase in dFe concentration. In early winter, strengthened northwesterly winds excite southward Ekman transport and Ekman upwelling over the western subarctic gyre, transporting dFe-rich water southward. In mid to late winter, the southward western boundary current of the subarctic gyre and the outflow from the Sea of Okhotsk also bring dFe-rich water to the Oyashio region. The contribution of atmospheric dust to the dFe budget is several times smaller than these ocean transport processes in winter. These results suggest that the westerly wind-induced Ekman transport and gyre circulation systematically influence the seasonal cycle of WSNP surface dFe concentration.

  18. Annual results 2004; Resultats annuels 2004

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This 2004 annual evaluation of the french RTE company (electric power transport network) provides information on the 2004 results on: institutional information, financial results, customers and market, industrial resources, environment and consultation, human resources and international aspects. (A.L.B.)

  19. CSIR Annual report 1978

    CSIR Research Space (South Africa)

    CSIR

    1978-01-01

    Full Text Available stream_source_info Annual Report_1978.pdf.txt stream_content_type text/plain stream_size 78 Content-Encoding ISO-8859-1 stream_name Annual Report_1978.pdf.txt Content-Type text/plain; charset=ISO-8859-1 ...

  20. CSIR Annual report 1972

    CSIR Research Space (South Africa)

    CSIR

    1972-01-01

    Full Text Available stream_source_info Annual Report_ 1972.pdf.txt stream_content_type text/plain stream_size 95 Content-Encoding ISO-8859-1 stream_name Annual Report_ 1972.pdf.txt Content-Type text/plain; charset=ISO-8859-1 ...

  1. 55th Annual

    Indian Academy of Sciences (India)

    1990-01-01

    Jan 1, 1990 ... At the invitation of the Madhya Pradesh. Council of Science and Technology, the. Barkatullah University and the Regional. Research laboratory, Bhopal, the 55th Annual. Meeting of the Academy was held at the. Tagore Bhawan, Bhopal from 10 to 13. November 1989. One of the best organized Annual.

  2. Annual Report 1997

    Energy Technology Data Exchange (ETDEWEB)

    Golnik, N.; Mika, J.R.; Wieteska, K. [eds.

    1998-12-31

    This Annual Report of the Institute of Atomic Energy describes the results of the research works carried out at the Institute at 1997. As in the preceding years the authors of the individual scientific reports published in this Annual Report are fully responsible for their content and layout. The Report contains the information on other activities of the Institute as well. (author)

  3. Long-term warming of a subarctic heath decreases soil bacterial community growth but has no effects on its temperature adaptation

    DEFF Research Database (Denmark)

    Rinnan, Riikka; Michelsen, Anders; Bååth, E

    2011-01-01

    We tested whether bacterial communities of subarctic heath soil are adapted to elevated temperature after experimental warming by open-top greenhouses for 7 or 17 years. The long-term warming by 1–2 °C significantly decreased bacterial community growth, by 28% and 73% after 7 and 17 years......, respectively. The decrease was most likely due to decreased availability of labile substrate under warming. However, we found no evidence for temperature adaptation of soil bacterial communities. The optimum temperature for bacterial growth was on average 25 °C, and the apparent minimum temperature for growth...

  4. Iron availability, nitrate uptake, and exportable new production in the subarctic Pacific. [phytoplankton population growth support and atmospheric CO2 removal

    Science.gov (United States)

    Banse, Karl

    1991-01-01

    This paper presents a critique of experimental data and papers by Martin et al. (1989, 1990), who suggested that the phytoplankton growth is iron-limited and that, small additions of iron to large subarctic ocean areas might be a way of removing significant amounts of atmospheric CO2 by increasing phytoplancton growth. Data are presented to show that, in the summer of 1987, the phytoplankton assemblage as a whole was not iron limited, as measured by the bulk removal of nitrate or by the increase of chlorophyll. It is suggested that grazing normally prevents the phytoplankton from reaching concentrations that reduce the iron (and nitrate) to levels that depress division rates drastically.

  5. /sup 99/Tc in the sub-arctic food chain lichen-reindeer-man

    Energy Technology Data Exchange (ETDEWEB)

    Holm, E.; Rioseco, J.

    1987-01-01

    The deposition, migration and annual variations of /sup 99/Tc fallout in carpets of lichen collected during the period 1956-1981 have been investigated. The transfer of /sup 99/Tc to reindeer and man has also been studied. Technetium showed a shorter mean residence time than /sup 137/Cs in the lichen carpet. The activity ratio /sup 99/Tc//sup 137/Cs was generally lower than the theoretical fission ratio of 1.43 x 10/sup -4/. The maximum concentration of /sup 99/Tc in lichens occurred in 1967 (ca. 60 mBq kg/sup -1/) but in 1975 higher values were found than would have been predicted from fallout. The average depth integrated concentration of /sup 99/Tc at 62.3/sup 0/ N, 12.4/sup 0/ E in 1972 was 540 +- 100 mBq m/sup -2/. The studies of reindeer tissues show that technetium has a short mean residence time in the muscle tissues (ca. 5 days) and is not accumulated like /sup 137/Cs. The committed dose equivalent from /sup 99/Tc to the local Lapp population engaged in reindeer breeding is negligible.

  6. The downward flux of biogenic material in the NE subarctic Pacific: importance of algal sinking and mesozooplankton herbivory

    Science.gov (United States)

    Thibault, D.; Roy, S.; Wong, C. S.; Bishop, J. K.

    1999-11-01

    In the present study we examine factors that affect the downward flux of biogenic carbon in the NE subarctic Pacific, one of the important high-nutrient-low-chlorophyll (HNLC) regions in the open ocean. We focus on the role of mesozooplankton, since their seasonal peaks in biomass and growth are in phase with the seasonal variations in the downward POC fluxes, whereas phytoplankton biomass is more-or-less uniform year-round. The relative importance of mesozooplankton and algal sinking was examined using the pigment composition of material accumulated in short-term free-drifting sediment traps positioned just below the upper stratified surface layer (ca. 100-200 m). This was compared with the phytoplankton composition in the surface waters, and with the grazing activity (gut pigments and fecal pellet production rates) of the most abundant large copepods. We also examined whether the relationships between the downward flux of carbon and pelagic processes were similar in the coastal, continental margin and offshore HNLC regions of the NE subarctic Pacific, the latter represented by Ocean Station Papa (OSP). Our results show that grazing had a variable impact on the downward flux of biogenic carbon. Carbon-transformed pheopigments (particularly pyropheophorbide a, frequently associated with copepod grazing) represented up to 13% of the total downward POC flux inshore (in May 1996) and 8-9% at OSP in May and February 1996, respectively. This flux of pheopigments was accompanied by a large potential input of fecal pellets from large copepods (as estimated from defecation rates of freshly collected animals) only in May 1996 at OSP, suggesting that pheopigments came from other sources (other herbivores, senescing algae) in February. The larger flux of pheopigments in May was probably related to the abundance of mesozooplankton at that time of the year. During summer (August 1996), both the flux of pheopigments and the potential input of fecal pellets from large copepods

  7. Annual energy review 2003

    Energy Technology Data Exchange (ETDEWEB)

    Seiferlein, Katherin E. [Energy Information Adminstration (EIA), Washington, DC (United States)

    2004-09-30

    The Annual Energy Review 2003 is a statistical history of energy activities in the United States in modern times. Data are presented for all major forms of energy by production (extraction of energy from the earth, water, and other parts of the environment), consumption by end-user sector, trade with other nations, storage changes, and pricing. Much of the data provided covers the fossil fuels—coal, petroleum, and natural gas. Fossil fuels are nature’s batteries; they have stored the sun’s energy over millennia past. It is primarily that captured energy that we are drawing on today to fuel the activities of the modern economy. Data in this report measure the extraordinary expansion of our use of fossil fuels from 29 quadrillion British thermal units (Btu) in 1949 to 84 quadrillion Btu in 2003. In recent years, fossil fuels accounted for 86 percent of all energy consumed in the United States. This report also records the development of an entirely new energy industry—the nuclear electric power industry. The industry got its start in this country in 1957 when the Shippingport, Pennsylvania, nuclear electric power plant came on line. Since that time, the industry has grown to account for 20 percent of our electrical output and 8 percent of all energy used in the country. Renewable energy is a third major category of energy reported in this volume. Unlike fossil fuels, which are finite in supply, renewable energy is essentially inexhaustible because it can be replenished. Types of energy covered in the renewable category include conventional hydroelectric power, which is power derived from falling water; wood; waste; alcohol fuels; geothermal; solar; and wind. Together, these forms of energy accounted for about 6 percent of all U.S. energy consumption in recent years.

  8. Annual energy review 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-01

    The Annual Energy Review (AER) is a historical data report that tells many stories. It describes, in numbers, the changes that have occurred in US energy markets since the midpoint of the 20th century. In many cases, those markets differ vastly from those of a half-century ago. By studying the graphs and data tables presented in this report, readers can learn about past energy supply and usage in the United States and gain an understanding of the issues in energy and the environment now before use. While most of this year`s report content is similar to last year`s, there are some noteworthy developments. Table 1.1 has been restructured into more summarized groupings -- fossil fuels, nuclear electric power, and renewable energy -- to aid analysts in their examination of the basic trends in those broad categories. Readers` attention is also directed to the electricity section, where considerable reformatting of the tables and graphs has been carried out to help clarify past and recent trends in the electric power industry as it enters a period of radical restructuring. Table 9.1, which summarizes US nuclear generating units, has been redeveloped to cover the entire history of the industry in this country and to provide categories relevant in assessing the future of the industry, such as the numbers of ordered generating units that have been canceled and those that were built and later shut down. In general, the AER emphasizes domestic energy statistics. Sections 1 through 10 and Section 12 are devoted mostly to US data; Section 11 reports on international statistics and world totals. 140 figs., 141 tabs.

  9. Impacts of winter icing events on the growth, phenology and physiology of sub-arctic dwarf shrubs.

    Science.gov (United States)

    Preece, Catherine; Callaghan, Terry V; Phoenix, Gareth K

    2012-12-01

    The Arctic is experiencing the greatest climate change in winter, including increases in freeze-thaw cycles that can result in ice encasement of vegetation. Ice encasement can expose plants to hypoxia and greater temperature extremes, but currently the impacts of icing on plants in the field remain little understood. With this in mind, a unique field manipulation experiment was established in heathland in northern Sweden with ice encasement simulated in early March 2008, 2009 and 2010 until natural thaw each spring. In the following summers we assessed the impacts on flowering, bud phenology, shoot growth and mortality and leaf damage (measured by chlorophyll fluorescence and electrolyte leakage) of the three dominant dwarf shrub species Empetrum nigrum, Vaccinium vitis-idaea (both evergreen) and Vaccinium myrtillus (deciduous). Two consecutive winters of icing decreased V. vitis-idaea flowering by 57%, while flowering of V. myrtillus and E. nigrum remained unaffected. Vaccinium myrtillus showed earlier budburst but shoot growth for all species was unchanged. Shoot mortality of V. myrtillus and V. vitis-idaea increased after the first year (by 70 and 165%, respectively) and again for V. myrtillus following the third year (by 67%), while E. nigrum shoot mortality remained unaffected, as were chlorophyll fluorescence and electrolyte leakage in all species. Overall, the sub-arctic heathland was relatively tolerant to icing, but the considerable shoot mortality of V. myrtillus contrasting with the general tolerance of E. nigrum suggests plant community structure in the longer term could change if winters continue to see a greater frequency of icing events. Copyright © Physiologia Plantarum 2012.

  10. Rapid carbon turnover beneath shrub and tree vegetation is associated with low soil carbon stocks at a subarctic treeline.

    Science.gov (United States)

    Parker, Thomas C; Subke, Jens-Arne; Wookey, Philip A

    2015-05-01

    Climate warming at high northern latitudes has caused substantial increases in plant productivity of tundra vegetation and an expansion of the range of deciduous shrub species. However significant the increase in carbon (C) contained within above-ground shrub biomass, it is modest in comparison with the amount of C stored in the soil in tundra ecosystems. Here, we use a 'space-for-time' approach to test the hypothesis that a shift from lower-productivity tundra heath to higher-productivity deciduous shrub vegetation in the sub-Arctic may lead to a loss of soil C that out-weighs the increase in above-ground shrub biomass. We further hypothesize that a shift from ericoid to ectomycorrhizal systems coincident with this vegetation change provides a mechanism for the loss of soil C. We sampled soil C stocks, soil surface CO2 flux rates and fungal growth rates along replicated natural transitions from birch forest (Betula pubescens), through deciduous shrub tundra (Betula nana) to tundra heaths (Empetrum nigrum) near Abisko, Swedish Lapland. We demonstrate that organic horizon soil organic C (SOCorg ) is significantly lower at shrub (2.98 ± 0.48 kg m(-2) ) and forest (2.04 ± 0.25 kg m(-2) ) plots than at heath plots (7.03 ± 0.79 kg m(-2) ). Shrub vegetation had the highest respiration rates, suggesting that despite higher rates of C assimilation, C turnover was also very high and less C is sequestered in the ecosystem. Growth rates of fungal hyphae increased across the transition from heath to shrub, suggesting that the action of ectomycorrhizal symbionts in the scavenging of organically bound nutrients is an important pathway by which soil C is made available to microbial degradation. The expansion of deciduous shrubs onto potentially vulnerable arctic soils with large stores of C could therefore represent a significant positive feedback to the climate system. © 2014 John Wiley & Sons Ltd.

  11. Seasonal variations in methane fluxes in response to summer warming and leaf litter addition in a subarctic heath ecosystem

    Science.gov (United States)

    Pedersen, Emily Pickering; Elberling, Bo; Michelsen, Anders

    2017-08-01

    Methane (CH4) is a powerful greenhouse gas controlled by both biotic and abiotic processes. Few studies have investigated CH4 fluxes in subarctic heath ecosystems, and climate change-induced shifts in CH4 flux and the overall carbon budget are therefore largely unknown. Hence, there is an urgent need for long-term in situ experiments allowing for the study of ecosystem processes over time scales relevant to environmental change. Here we present in situ CH4 and CO2 flux measurements from a wet heath ecosystem in northern Sweden subjected to 16 years of manipulations, including summer warming with open-top chambers, birch leaf litter addition, and the combination thereof. Throughout the snow-free season, the ecosystem was a net sink of CH4 and CO2 (CH4 -0.27 mg C m-2 d-1; net ecosystem exchange -1827 mg C m-2 d-1), with highest CH4 uptake rates (-0.70 mg C m-2 d-1) during fall. Warming enhanced net CO2 flux, while net CH4 flux was governed by soil moisture. Litter addition and the combination with warming significantly increased CH4 uptake rates, explained by a pronounced soil drying effect of up to 32% relative to ambient conditions. Both warming and litter addition also increased the seasonal average concentration of dissolved organic carbon in the soil. The site was a carbon sink with a net uptake of 60 g C m-2 over the snow-free season. However, warming reduced net carbon uptake by 77%, suggesting that this ecosystem type might shift from snow-free season sink to source with increasing summer temperatures.

  12. Trophic dynamics of shrinking Subarctic lakes: naturally eutrophic waters impart resilience to rising nutrient and major ion concentrations.

    Science.gov (United States)

    Lewis, Tyler L; Heglund, Patricia J; Lindberg, Mark S; Schmutz, Joel A; Schmidt, Joshua H; Dubour, Adam J; Rover, Jennifer; Bertram, Mark R

    2016-06-01

    Shrinking lakes were recently observed for several Arctic and Subarctic regions due to increased evaporation and permafrost degradation. Along with lake drawdown, these processes often boost aquatic chemical concentrations, potentially impacting trophic dynamics. In particular, elevated chemical levels may impact primary productivity, which may in turn influence populations of primary and secondary consumers. We examined trophic dynamics of 18 shrinking lakes of the Yukon Flats, Alaska, that had experienced pronounced increases in nutrient (>200 % total nitrogen, >100 % total phosphorus) and ion concentrations (>100 % for four major ions combined) from 1985-1989 to 2010-2012, versus 37 stable lakes with relatively little chemical change over the same period. We found that phytoplankton stocks, as indexed by chlorophyll concentrations, remained unchanged in both shrinking and stable lakes from the 1980s to 2010s. Moving up the trophic ladder, we found significant changes in invertebrate abundance across decades, including decreased abundance of five of six groups examined. However, these decadal losses in invertebrate abundance were not limited to shrinking lakes, occurring in lakes with stable surface areas as well. At the top of the food web, we observed that probabilities of lake occupancy for ten waterbird species, including adults and chicks, remained unchanged from the period 1985-1989 to 2010-2012. Overall, our study lakes displayed a high degree of resilience to multi-trophic cascades caused by rising chemical concentrations. This resilience was likely due to their naturally high fertility, such that further nutrient inputs had little impact on waters already near peak production.

  13. Enzymatic regulation of glycogenolysis in a subarctic population of the wood frog: implications for extreme freeze tolerance.

    Directory of Open Access Journals (Sweden)

    M Clara F do Amaral

    Full Text Available The wood frog, Rana sylvatica, from Interior Alaska survives freezing at -16°C, a temperature 10-13°C below that tolerated by its southern conspecifics. We investigated the hepatic freezing response in this northern phenotype to determine if its profound freeze tolerance is associated with an enhanced glucosic cryoprotectant system. Alaskan frogs had a larger liver glycogen reserve that was mobilized faster during early freezing as compared to conspecifics from a cool-temperate region (southern Ohio, USA. In Alaskan frogs the rapid glucose production in the first hours of freezing was associated with a 7-fold increase in glycogen phosphorylase activity above unfrozen frog levels, and the activity of this enzyme was higher than that of frozen Ohioan frogs. Freezing of Ohioan frogs induced a more modest (4-fold increase in glycogen phosphorylase activity above unfrozen frog values. Relative to the Ohioan frogs, Alaskan frogs maintained a higher total protein kinase A activity throughout an experimental freezing/thawing time course, and this may have potentiated glycogenolysis during early freezing. We found populational variation in the activity and protein level of protein kinase A which suggested that the Alaskan population had a more efficient form of this enzyme. Alaskan frogs modulated their glycogenolytic response by decreasing the activity of glycogen phosphorylase after cryoprotectant mobilization was well under way, thereby conserving their hepatic glycogen reserve. Ohioan frogs, however, sustained high glycogen phosphorylase activity until early thawing and consumed nearly all their liver glycogen. These unique hepatic responses of Alaskan R. sylvatica likely contribute to this phenotype's exceptional freeze tolerance, which is necessary for their survival in a subarctic climate.

  14. Warming of subarctic tundra increases emissions of all three important greenhouse gases - carbon dioxide, methane, and nitrous oxide.

    Science.gov (United States)

    Voigt, Carolina; Lamprecht, Richard E; Marushchak, Maija E; Lind, Saara E; Novakovskiy, Alexander; Aurela, Mika; Martikainen, Pertti J; Biasi, Christina

    2017-08-01

    Rapidly rising temperatures in the Arctic might cause a greater release of greenhouse gases (GHGs) to the atmosphere. To study the effect of warming on GHG dynamics, we deployed open-top chambers in a subarctic tundra site in Northeast European Russia. We determined carbon dioxide (CO 2 ), methane (CH 4 ), and nitrous oxide (N 2 O) fluxes as well as the concentration of those gases, inorganic nitrogen (N) and dissolved organic carbon (DOC) along the soil profile. Studied tundra surfaces ranged from mineral to organic soils and from vegetated to unvegetated areas. As a result of air warming, the seasonal GHG budget of the vegetated tundra surfaces shifted from a GHG sink of -300 to -198 g CO 2 -eq m -2 to a source of 105 to 144 g CO 2 -eq m -2 . At bare peat surfaces, we observed increased release of all three GHGs. While the positive warming response was dominated by CO 2 , we provide here the first in situ evidence of increasing N 2 O emissions from tundra soils with warming. Warming promoted N 2 O release not only from bare peat, previously identified as a strong N 2 O source, but also from the abundant, vegetated peat surfaces that do not emit N 2 O under present climate. At these surfaces, elevated temperatures had an adverse effect on plant growth, resulting in lower plant N uptake and, consequently, better N availability for soil microbes. Although the warming was limited to the soil surface and did not alter thaw depth, it increased concentrations of DOC, CO 2, and CH 4 in the soil down to the permafrost table. This can be attributed to downward DOC leaching, fueling microbial activity at depth. Taken together, our results emphasize the tight linkages between plant and soil processes, and different soil layers, which need to be taken into account when predicting the climate change feedback of the Arctic. © 2016 John Wiley & Sons Ltd.

  15. Late Cretaceous climate simulations with different CO2 levels and subarctic gateway configurations: A model-data comparison

    Science.gov (United States)

    Niezgodzki, Igor; Knorr, Gregor; Lohmann, Gerrit; Tyszka, Jarosław; Markwick, Paul J.

    2017-09-01

    We investigate the impact of different CO2 levels and different subarctic gateway configurations on the surface temperatures during the latest Cretaceous using the Earth System Model COSMOS. The simulated temperatures are compared with the surface temperature reconstructions based on a recent compilation of the latest Cretaceous proxies. In our numerical experiments, the CO2 level ranges from 1 to 6 times the preindustrial (PI) CO2 level of 280 ppm. On a global scale, the most reasonable match between modeling and proxy data is obtained for the experiments with 3 to 5 × PI CO2 concentrations. However, the simulated low- (high-) latitude temperatures are too high (low) as compared to the proxy data. The moderate CO2 levels scenarios might be more realistic, if we take into account proxy data and the dead zone effect criterion. Furthermore, we test if the model-data discrepancies can be caused by too simplistic proxy-data interpretations. This is distinctly seen at high latitudes, where most proxies are biased toward summer temperatures. Additional sensitivity experiments with different ocean gateway configurations and constant CO2 level indicate only minor surface temperatures changes (< 1°C) on a global scale, with higher values (up to 8°C) on a regional scale. These findings imply that modeled and reconstructed temperature gradients are to a large degree only qualitatively comparable, providing challenges for the interpretation of proxy data and/or model sensitivity. With respect to the latter, our results suggest that an assessment of greenhouse worlds is best constrained by temperatures in the midlatitudes.

  16. Climate Variability in the Subarctic Area for the Last Two Millennia: Influence of North Atlantic Sector and Millennial Trend.

    Science.gov (United States)

    Nicolle, M.; Debret, M.; Massei, N.; Hormes, A.; Swingedouw, D.; Christophe, C.; de Vernal, A.; Arctic 2k Working Group

    2016-12-01

    Understanding climate variability for the last two millennia is an key issue to propose new constraints on climate modeling. This study is based on the Arctic2k database compiled by the PAGES Arctic2k working group. All records meet several quality criteria concerning location, time period span, resolution and age-dating control. All the proxy used are sensitivity to temperature changes. The database high quality allows to investigate climate variability from millennial trend to high frequencies. There is spatially heterogeneous record distribution throughout the Arctic-subarctic area, most of the archives being located in the North Atlantic sector. We divided the study region into 3 sectors (Siberia, Alaska and North Atlantic areas) and compared them to the global Arctic2k temperature reconstruction using statistics and signal analysis method (wavelet coherence). Wavelet coherence allows investigation of the relationships in time-frequency space between two time series and identification of common variability. The results highlight better significant correlations between North Atlantic and global Arctic signals. The results is confirmed by wavelet coherence, showing common variability at centennial to multi-centennial scales. Millennial trends showed significant cooling trends before 1900 A.D., except for two records. Cooling trends are consistent with reconstructed temperatures for north hemisphere and warming trends seemed to be the results of regional particularity. Studying millennial variability also highlights the inconsistency between some marine proxies which reflect summer temperatures. The characterization of centennial to multidecadal variability will be an important issue to link the high frequency variability of paleoclimate series to low frequency variability recorded by instrumental data.

  17. Enzymatic regulation of glycogenolysis in a subarctic population of the wood frog: implications for extreme freeze tolerance.

    Science.gov (United States)

    do Amaral, M Clara F; Lee, Richard E; Costanzo, Jon P

    2013-01-01

    The wood frog, Rana sylvatica, from Interior Alaska survives freezing at -16°C, a temperature 10-13°C below that tolerated by its southern conspecifics. We investigated the hepatic freezing response in this northern phenotype to determine if its profound freeze tolerance is associated with an enhanced glucosic cryoprotectant system. Alaskan frogs had a larger liver glycogen reserve that was mobilized faster during early freezing as compared to conspecifics from a cool-temperate region (southern Ohio, USA). In Alaskan frogs the rapid glucose production in the first hours of freezing was associated with a 7-fold increase in glycogen phosphorylase activity above unfrozen frog levels, and the activity of this enzyme was higher than that of frozen Ohioan frogs. Freezing of Ohioan frogs induced a more modest (4-fold) increase in glycogen phosphorylase activity above unfrozen frog values. Relative to the Ohioan frogs, Alaskan frogs maintained a higher total protein kinase A activity throughout an experimental freezing/thawing time course, and this may have potentiated glycogenolysis during early freezing. We found populational variation in the activity and protein level of protein kinase A which suggested that the Alaskan population had a more efficient form of this enzyme. Alaskan frogs modulated their glycogenolytic response by decreasing the activity of glycogen phosphorylase after cryoprotectant mobilization was well under way, thereby conserving their hepatic glycogen reserve. Ohioan frogs, however, sustained high glycogen phosphorylase activity until early thawing and consumed nearly all their liver glycogen. These unique hepatic responses of Alaskan R. sylvatica likely contribute to this phenotype's exceptional freeze tolerance, which is necessary for their survival in a subarctic climate.

  18. Acoustic Monitoring of Ebullitive Flux from a Mire Ecosystem in Subarctic Sweden

    Science.gov (United States)

    Burke, S. A.; Varner, R. K.; Palace, M. W.; Wik, M.; Crill, P. M.; McCalley, C. K.; Amante, J.

    2012-12-01

    Methane (CH4) is a potent green house gas with wetlands being the largest natural source to the atmosphere. Studies in the Stordalen Mire, a dynamic peatland complex 11km east of the Abisko Scientific Research Station (ANS) in northern Sweden, that focused on CH4 transport to the atmosphere from peatlands have shown increased emissions over the past decades. Ebullitive flux (bubbling) is a potentially significant pathway of CH4 from mire/lake ecosystems. Ebullitive fluxes were successfully monitored acoustically in peat and lakes in 2011. This work expands those measurements with installation of sensors in ponds and permafrost thaw margins in 2012. Eighteen acoustic sensors were installed in peat (6), pond (6), and lake (6) sites at Stordalen Mire. Recorders collected acoustic data continuously from each sensor and gas samples were collected from the traps at least once per week beginning 7 July. The CH4 concentration in the gas was measured using gas chromatography and selected samples were also analyzed for 13C-CH4 using a Quantum Cascade Laser (QCL). The acoustic data were evaluated using a MATLAB program for determine the timing and volume of each ebullition event. The CH4 ebullitive flux from the peat was greater in July 2011 than during the same period in 2012. In comparison, the ponds and thaw margins released CH4 at a faster rate in 2012 than was observed in the peat and lake sensors in 2011. Inter-annual differences in ebullitive rates suggest that weather scale differences between years may control CH4 ebullitive flux. 13C-CH4 measured in the pore waters of pond sediment suggests that not all ponds are dominated by the same production processes. However, 13C-CH4 measured in bubbles and sediments are not different, implying little or no oxidation of CH4 during transport to the water surface. Our data suggests that changes in atmospheric pressure and water table height correlated with the ebullitive release in all three sub-ecosystems.

  19. Evolution of the snow area index of the subarctic snowpack in central Alaska over a whole season. consequences for the air to snow transfer of pollutants.

    Science.gov (United States)

    Taillandier, A S; Domine, F; Simpson, W R; Sturm, M; Douglas, T A; Severin, K

    2006-12-15

    The detailed physical characteristics of the subarctic snowpack must be known to quantify the exchange of adsorbed pollutants between the atmosphere and the snow cover. For the first time, the combined evolutions of specific surface area (SSA), snow stratigraphy, temperature, and density were monitored throughout winter in central Alaska. We define the snow area index (SAI) as the vertically integrated surface area of snow crystals, and this variable is used to quantify pollutants' adsorption. Intense metamorphism generated by strong temperature gradients formed a thick depth hoar layer with low SSA (90 cm(2) g-1) and density (200 kg m(-3)), resulting in a low SAI. After snowpack buildup in autumn, the winter SAI remained around 1000 m(2)/m(2) of ground, much lower than the SAI of the Arctic snowpack, 2500 m(2) m-(2). With the example of PCBs 28 and 180, we calculate that the subarctic snowpack is a smaller reservoir of adsorbed pollutants than the Arctic snowpack and less efficiently transfers adsorbed pollutants from the atmosphere to ecosystems. The difference is greater for the more volatile PCB 28. With climate change, snowpack structure will be modified, and the snowpack's ability to transfer adsorbed pollutants from the atmosphere to ecosystems may be reduced, especially for the more volatile pollutants.

  20. Super-cooled liquid water topped sub-arctic clouds and precipitation - investigation based on combination of ground-based in-situ and remote-sensing observations

    Science.gov (United States)

    Hirsikko, Anne; Brus, David; O'Connor, Ewan J.; Filioglou, Maria; Komppula, Mika; Romakkaniemi, Sami

    2017-04-01

    In the high and mid latitudes super-cooled liquid water layers are frequently observed on top of clouds. These layers are difficult to forecast with numerical weather prediction models, even though, they have strong influence on atmospheric radiative properties, cloud microphysical properties, and subsequently, precipitation. This work investigates properties of super-cooled liquid water layer topped sub-arctic clouds and precipitation observed with ground-based in-situ (cloud probes) and remote-sensing (a cloud radar, Doppler and multi-wavelength lidars) instrumentation during two-month long Pallas Cloud Experiment (PaCE 2015) in autumn 2015. Analysis is based on standard Cloudnet scheme supplemented with new retrieval products of the specific clouds and their properties. Combination of two scales of observation provides new information on properties of clouds and precipitation in the sub-arctic Pallas region. Current status of results will be presented during the conference. The authors acknowledge financial support by the Academy of Finland (Centre of Excellence Programme, grant no 272041; and ICINA project, grant no 285068), the ACTRIS2 - European Union's Horizon 2020 research and innovation programme under grant agreement No 654109, the KONE foundation, and the EU FP7 project BACCHUS (grant no 603445).

  1. Responses of fungal root colonization, plant cover and leaf nutrients to long-term exposure to elevated atmospheric CO2 and warming in a subarctic birch forest understory

    DEFF Research Database (Denmark)

    Olsrud, Maria; Carlsson, Bengt Å.; Svensson, Brita M.

    2010-01-01

    to the fungal symbionts. In this study, we investigated how ericoid mycorrhiza (ErM), fine endophytes (FE) and dark septate endophytes (DSE) in roots responded to elevated atmospheric CO2 concentrations and warming in the dwarf shrub understory of a birch forest in the subarctic region of northern Sweden...

  2. CSIR Annual report 2013-14

    CSIR Research Space (South Africa)

    CSIR

    2013-01-01

    Full Text Available and mitigation to the national government and to several South African metropolitan municipalities (eThekwini, Cape Town and Johannesburg) and sectors such as agriculture, insurance, mining and energy. CSIR ANNUAL REPORT 2013/14 17 ouTCoMES Better... to the impact of mining. Project highlights CSIR ANNUAL REPORT 2013/1424 ProJ E CT H I G H L I G HTS Natural environment ouTCoME Ecological infrastructure heeded in development decisions The recommendation to politicians and decision-makers focused...

  3. Annual Trapping Proposal 1985

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Annual Trapping Plan for the 1984-1985 trapping season at Clarence Cannon NWR outlines rules and regulations for the trapping of beaver and muskrat on the...

  4. Annual Adjustment Factors

    Data.gov (United States)

    Department of Housing and Urban Development — The Department of Housing and Urban Development establishes the rent adjustment factors - called Annual Adjustment Factors (AAFs) - on the basis of Consumer Price...

  5. ASIST 2002 annual meeting

    CERN Multimedia

    Peek, R

    2003-01-01

    Review of discussions and presentations at the American Society for Information Science and Technology 2002 annual meeting. Topics covered included new models of scholarly publishing and the development of the semantic web (1 page).

  6. USRDS - Annual Data Report

    Data.gov (United States)

    U.S. Department of Health & Human Services — United States Renal Data System (USRDS) Annual Data Report Comprehensive statistics on chronic kidney disease and end-stage renal diseases in the United States...

  7. 2010 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    None

    2010-01-01

    This annual report includes: an overview of Western; approaches for future hydropower and transmission service; major achievements in FY 2010; FY 2010 customer Integrated Resource Planning, or IRP, survey; and financial data.

  8. SIS - Annual Catch Limit

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Annual Catch Limit (ACL) dataset within the Species Information System (SIS) contains information and data related to management reference points and catch data.

  9. Annual General Canvass Statistics

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains annual quantities and value for all seafood products that are landed and sold by established seafood dealers and brokers in the Southeast...

  10. Natural gas annual 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-11-17

    The Natural Gas Annual provides information on the supply and disposition of natural gas to a wide audience including industry, consumers, Federal and State agencies, and educational institutions. The 1994 data are presented in a sequence that follows natural gas (including supplemental supplies) from its production to its end use. This is followed by tables summarizing natural gas supply and disposition from 1990 to 1994 for each Census Division and each State. Annual historical data are shown at the national level.

  11. Heavy metal contents in whitefish (Coregonus lavaretus) along a pollution gradient in a subarctic watercourse.

    Science.gov (United States)

    Amundsen, Per-Arne; Kashulin, Nikolay A; Terentjev, Petr; Gjelland, Karl Øystein; Koroleva, Irina M; Dauvalter, Vladimir A; Sandimirov, Sergey; Kashulin, Alexander; Knudsen, Rune

    2011-11-01

    Metallurgic industry is a source of serious environmental pollution related to the emission of heavy metals. Freshwater systems are focal points for pollution, acting as sinks for contaminants that may end up in fish and humans. The Pasvik watercourse in the border area between Finland, Norway and Russia is located in the vicinity of the Pechenganickel metallurgic enterprises, and the lower part of the watershed drains the Nikel smelters directly through Lake Kuetsjarvi. Heavy metal (Ni, Cu, Cd, Zn, Pb and Hg) concentrations in environment (water and sediments) and whitefish Coregonus lavaretus tissue (gills, liver, kidney and muscle) were contrasted between five lake localities situated along a spatial gradient of increasing distance (5-100 km) to the smelters. The heavy metal concentrations, in particular Ni, Cu and Cd, were highly elevated in Kuetsjarvi, but steeply declined with increasing distance to the smelters and were moderate or low in the other four localities. The study demonstrates that the majority of metal emissions and runoffs are deposited near the pollution source, and only moderate amounts of the heavy metal contaminants seem to be transported at further distances. Bioaccumulation of Hg occurred in all investigated tissues, and higher Hg concentrations in planktivorous versus benthivorous whitefish furthermore indicated that pelagic foraging is associated with higher levels of Hg biomagnification. Potential population ecology impacts of high heavy metal contaminations where mainly observed in whitefish in Kuetsjarvi, which showed depletions in growth rate, condition factor and size and age at maturation.

  12. Role of EPS, Dispersant and Nutrients on the Microbial Response and MOS Formation in the Subarctic Northeast Atlantic

    Directory of Open Access Journals (Sweden)

    Tony Gutierrez

    2017-04-01

    Full Text Available In this study we report the formation of marine oil snow (MOS, its associated microbial community, the factors influencing its formation, and the microbial response to crude oil in surface waters of the Faroe-Shetland Channel (FSC. The FSC is a subarctic region that is hydrodynamically complex located in the northeast Atlantic where oil extraction is currently occurring and where exploration is likely to expand into its deeper waters (>500 m. A major oil spill in this region may mirror the aftermath that ensued following the Deepwater Horizon (DWH blowout in the Gulf of Mexico, where the massive influx of Macondo crude oil triggered the formation of copious quantities of rapidly sinking MOS and successional blooms of opportunistic oil-degrading bacteria. In laboratory experiments, we simulated environmental conditions in sea surface waters of the FSC using water collected from this site during the winter of 2015. We demonstrated that the presence of dispersant triggers the formation of MOS, and that nutrient amendments magnify this. Illumina MiSeq sequencing revealed the enrichment on MOS of associated oil-degrading (Cycloclasticus, Thalassolituus, Marinobacter and EPS-producing (Halomonas, Pseudoalteromonas, Alteromonas bacteria, and included major representation by Psychrobacter and Cobetia with putative oil-degrading/EPS-producing qualities. The formation of marine snow, in the absence of crude oil and dispersant, in seawater amended with nutrients alone indicated that the de novo synthesis of bacterial EPS is a key factor in MOS formation, and the glycoprotein composition of the MOS aggregates confirmed that its amorphous biopolymeric matrix was of microbial (likely bacterial origin. The presence of dispersants and crude oil with/without nutrients resulted in distinct microbial responses marked by intermittent, and in some cases short-lived, blooms of opportunistic heterotrophs, principally obligate hydrocarbonoclastic (Alcanivorax

  13. A Greener Arctic: Vascular Plant Litter Input in Subarctic Peat Bogs Changes Soil Invertebrate Diets and Decomposition Patterns

    Science.gov (United States)

    Krab, E. J.; Berg, M. P.; Aerts, R.; van Logtestijn, R. S. P.; Cornelissen, H. H. C.

    2014-12-01

    Climate-change-induced trends towards shrub dominance in subarctic, moss-dominated peatlands will most likely have large effects on soil carbon (C) dynamics through an input of more easily decomposable litter. The mechanisms by which this increase in vascular litter input interacts with the abundance and diet-choice of the decomposer community to alter C-processing have, however, not yet been unraveled. We used a novel 13C tracer approach to link invertebrate species composition (Collembola), abundance and species-specific feeding behavior to C-processing of vascular and peat moss litters. We incubated different litter mixtures, 100% Sphagnum moss litter, 100% Betula leaf litter, and a 50/50 mixture of both, in mesocosms for 406 days. We revealed the transfer of C from the litters to the soil invertebrate species by 13C labeling of each of the litter types and assessed 13C signatures of the invertebrates Collembola species composition differed significantly between Sphagnum and Betula litter. Within the 'single type litter' mesocosms, Collembola species showed different 13C signatures, implying species-specific differences in diet choice. Surprisingly, the species composition and Collembola abundance changed relatively little as a consequence of Betula input to a Sphagnum based system. Their diet choice, however, changed drastically; species-specific differences in diet choice disappeared and approximately 67% of the food ingested by all Collembola originated from Betula litter. Furthermore, litter decomposition patterns corresponded to these findings; mass loss of Betula increased from 16.1% to 26.2% when decomposing in combination with Sphagnum, while Sphagnum decomposed even slower in combination with Betula litter (1.9%) than alone (4.7%). This study is the first to empirically show that collective diet shifts of the peatland decomposer community from mosses towards vascular plant litter may drive altered decomposition patterns. In addition, we showed that

  14. A comparison of mesopelagic mesozooplankton community structure in the subtropical and subarctic North Pacific Ocean

    Science.gov (United States)

    Steinberg, Deborah K.; Cope, Joseph S.; Wilson, Stephanie E.; Kobari, T.

    2008-07-01

    Mesopelagic mesozooplankton communities of an oligotrophic (Hawaii Ocean Time series-HOT station ALOHA) and a mesotrophic (Japanese time-series station K2) environment in the North Pacific Ocean are compared as part of a research program investigating the factors that control the efficiency of particle export to the deep sea (VERtical Transport In the Global Ocean—VERTIGO). We analyzed zooplankton (>350 μm) collected from net tows taken between 0 and 1000 m at each site to investigate the biomass size structure and the abundance of the major taxonomic groups in discrete depth intervals throughout the water column. Biomass of zooplankton at K2 over all depths was approximately an order of a magnitude higher than at ALOHA, with a significantly higher proportion of the biomass at K2 in the larger (>2 mm) size classes. This difference was mostly due to the abundance at K2 of the large calanoid copepods Neocalanus spp. and Eucalanus bungii, which undergo ontogenetic (seasonal) vertical migration. The overall strength of diel vertical migration was higher at K2, with a mean night:day biomass ratio in the upper 150 m of 2.5, vs. a ratio of 1.7 at ALOHA. However, the amplitude of the diel migration (change in weighted mean depth between day and night) was higher at ALOHA for all biomass size classes, perhaps due to deeper light penetration causing deeper migration to avoid visual predators. A number of taxa known to feed on suspended or sinking detritus showed distinct peaks in the mesopelagic zone, which affects particle transport efficiency at both sites. These taxa include calanoid and poecilostomatoid (e.g., Oncaea spp.) copepods, salps, polychaetes, and phaeodarian radiolaria at K2, harpacticoid copepods at ALOHA, and ostracods at both sites. We found distinct layers of carnivores (mainly gelatinous zooplankton) in the mesopelagic at K2 including chaetognaths, hydrozoan medusae, polychaetes, and gymnosome pteropods, and, in the upper mesopelagic zone, of

  15. Macroalgae contribute to nested mosaics of pH variability in a subarctic fjord

    KAUST Repository

    Krause-Jensen, D.

    2015-08-19

    and macrophyte diffusive boundary layers a pH range of up to 0.8 units. Overall, pelagic and benthic metabolism was an important driver of pH and Ωarag producing mosaics of variability from low levels in the dark to peak levels at high irradiance generally appearing favourable for calcification. We suggest that productive coastal environments may form niches of high pH in a future acidified Arctic Ocean.

  16. Primary productivity, nutrients, and other data from bottle casts in the Eastern Subarctic Pacific from the ENDEAVOUR and other platforms as part of the Outer Continental Shelf Environmental Assessment Program (OCSEAP) from 01 July 1958 to 25 July 1974 (NODC Accession 7601768)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Primary productivity, nutrients, and other data were collected from bottle casts in the Eastern Subarctic Pacific from the ENDEAVOUR and other platforms from 01 July...

  17. The Role of Eolian Dust Fertilization in Biogeochemical Cycles in The sub-Arctic Northwest Pacific During the Late Pliocene Intensification of Northern Hemisphere Glaciation

    Science.gov (United States)

    Bailey, I.; Liu, Q.; Swann, G.; Jiang, Z.; Sun, Y.; Zhao, X.; Roberts, A.

    2010-12-01

    Marine sediments recovered during Ocean Drilling Program (ODP) Leg 145 have improved our knowledge of climatic and oceanographic change in the North Pacific Ocean and surrounding landmasses during the last several million years. Of particular importance has been the analysis of high-latitude terrigenous sedimentary components sourced from the Asian continental interior via eolian deposition and from the circum-North Pacific landmasses via ice rafting. Teasing apart the relative contribution of eolian dust and ice-rafted debris (IRD) to deep sea sediments in the sub-Arctic Pacific is important for developing our understanding of late Pliocene ice-sheet evolution and the potential role of iron fertilization in biogeochemical cycles in the North Pacific Ocean. The magnetic properties of both eolian dust and IRD often have distinctive magnetic signatures, making environmental magnetism useful for investigating the relative importance of these sediment sources to bulk terrigenous inputs. Enhancements of the low-field volume magnetic susceptibility and the terrigenous sediment component from ODP Site 882 (~45°N) are classically interpreted to indicate a major onset of ice rafting to the sub-Arctic northwest Pacific Ocean during the late Pliocene (from ca MIS G6). On the other hand, studies of the eolian dust content of sediments from ODP Site 885, cored downwind of Site 882, indicate that dust deposition in the sub-Arctic Pacific increased markedly during MIS G6. This suggests that the classic interpretation of the magnetic susceptibility record at Site 882 requires reappraisal. To investigate the relative contribution of dust versus ice rafting to the Pliocene North Pacific, we present new high-resolution environmental magnetic and IRD records from ODP sites 882 and 885. We find that terrigenous inputs to both sites across MIS G6 were dominated by eolian dust (not IRD). Our findings call into question the reliability of magnetic susceptibility as a simple proxy for IRD

  18. Production and air-sea flux of halomethanes in the western subarctic Pacific in relation to phytoplankton pigment concentrations during the iron fertilization experiment (SEEDS II)

    Science.gov (United States)

    Hashimoto, Shinya; Toda, Shuji; Suzuki, Koji; Kato, Shungo; Narita, Yasusi; Kurihara, Michiko K.; Akatsuka, Yoko; Oda, Hiroshi; Nagai, Takahiro; Nagao, Ippei; Kudo, Isao; Uematsu, Mitsuo

    2009-12-01

    Iron could play a key role in controlling phytoplankton biomass and productivity in high-nutrient, low-chlorophyll regions. As a part of the iron fertilization experiment carried out in the western subarctic Pacific from July to August 2004 (Subarctic Pacific iron Experiment for Ecosystem Dynamics Study II—SEEDS II), we analysed the concentrations of trace gases in the seawater for 12 d following iron fertilization. The mean concentrations of chlorophyll a in the mixed layer (5-30 m depth) increased from 0.94 to 2.81 μg L -1 for 8 d in the iron patch. The mean concentrations of methyl bromide (CH 3Br; 5-30 m depth) increased from 6.4 to 13.4 pmol L -1 for 11 d; the in-patch concentration increased relative to the out-patch concentration. A linear correlation was observed between the concentrations of 19'-hexanoyloxyfucoxanthin, which is a biomarker of several prymnesiophytes, and CH 3Br in the seawater. After fertilization, the air-sea flux of CH 3Br inside the patch changed from influx to efflux from the ocean. There was no clear evidence for the increase in saturation anomaly of methyl chloride (CH 3Cl) due to iron fertilization. Furthermore, CH 3Cl fluxes did not show a tendency to increase after fertilization of the patch. In contrast to CH 3Br, no change was observed in the concentrations of bromoform (in-patch day 11 and out-patch day 11: 1.7 and 1.7 pmol L -1), dibromomethane (2.1 and 2.2 pmol L -1), and dibromochloromethane (1.0 and 1.2 pmol L -1, respectively). The concentration of isoprene, which is known to have a relationship with chlorophyll a, did not change in this study. The responses of trace gases during SEEDS II differed from the previous findings ( in situ iron enrichment experiment—EisenEx, Southern Ocean iron experiment—SOFeX, and Subarctic Ecosystem Response to Iron Enrichment Study—SERIES). Thus, in order to estimate the concomitant effect of iron fertilization on the climate, it is important to assess the induction of biological

  19. Natural gas annual 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-10-01

    The Natural Gas Annual provides information on the supply and disposition of natural gas to a wide audience including industry, consumers, Federal and State agencies, and educational institutions. The 1997 data are presented in a sequence that follows natural gas (including supplemental supplies) from its production to its end use. This is followed by tables summarizing natural gas supply and disposition from 1993 to 1997 for each Census Division and each State. Annual historical data are shown at the national level. 27 figs., 109 tabs.

  20. International energy annual 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-02-01

    The International Energy Annual presents an overview of key international energy trends for production, consumption, imports, and exports of primary energy commodities in over 220 countries, dependencies, and areas of special sovereignty. Also included are population and gross domestic product data, as well as prices for crude oil and petroleum products in selected countries. Renewable energy reported in the International Energy Annual includes hydroelectric power, geothermal, solar, and wind electric power, biofuels energy for the US, and biofuels electric power for Brazil. New in the 1996 edition are estimates of carbon dioxide emissions from the consumption of petroleum and coal, and the consumption and flaring of natural gas. 72 tabs.

  1. Variação anual de hormônios tireoideanos e características termorreguladoras de vacas leiteiras em ambiente quente Annual thyroid hormone variation and thermo regulators traits of milk cows in hot environment

    Directory of Open Access Journals (Sweden)

    Débora Andréa Evangelista Façanha Morais

    2008-03-01

    Full Text Available Este trabalho foi conduzido com o objetivo de estudar o comportamento anual de características termorreguladoras de 200 vacas leiteiras. Durante dois anos consecutivos, foram registradas a freqüência respiratória (FR e a temperatura retal (TR, bem como coletada uma amostra de sangue para dosagens de triiodotironina (T3 e tiroxina (T4. Foram também registradas a temperatura e a umidade do ar e calculados o índice de temperatura de globo e umidade (ITGU e a carga térmica radiante (CTR, nos mesmos dias de coleta. Houve efeito significativo do ano para a maioria das variáveis estudadas, no entanto, os efeitos do mês de coleta e do rebanho foram significativos para todas. Todos os valores de TR estiveram dentro da amplitude de normalidade, indicando homeotermia. A FR foi alterada em todas as épocas do ano e rebanhos, confirmando a necessidade constante de termólise. No rebanho de maior TR e a FR, houve redução da secreção de T3 e T4. Nas épocas de maiores ITGU e CTR, houve aumento da TR, seguido de maiores FR e menores concentrações plasmáticas de T3 e T4.This work was carried out with the objective to study the annual behavior of thermo regulators traits in dairy cows. Two hundred cows were used during two consecutive years and the respiratory rate (RR, rectal temperature (RT, as well as a blood sample was collected for triiodothyronin (T3 and thyroxin (T4 dosages, were recorded. Air temperature and humidity were also recorded and the black globe humidity index (BGHI and radiant heat load (RHL were calculated in the same days of data collection. There was no significative effect of the year for the majority of studied variables, however, the effects of month of collection and herd were significative for all variables. All values of RT were inside of the amplitude of normality, indicating homoeothermic condition. The RR was altered in every seasons of the year and herds, showing a constant necessity of thermolisys. In herds with

  2. Annual report 2009. Institute of Radiochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Bernhard, G. (ed.)

    2010-07-01

    The annual report 2009 of the institute of radiochemistry covers the following topics: Part 1: Actinides (metals) in biosystems; Part 2: Actinides in waste repositories. The research projects were aimed to the basic knowledge about coordination of actinide element transport and transfer in the environment, bacteria influence on the immobilization of heavy metals in water and soils, microbial diversity in biofilms and clays, protein applications for biosensors, dominating processes of soil-liquid interfaces, sorption and surface complexation processes.

  3. NERSC Annual Report 2005

    Energy Technology Data Exchange (ETDEWEB)

    Hules (Ed.), John

    2006-07-31

    The National Energy Research Scientific Computing Center (NERSC) is the premier computational resource for scientific research funded by the DOE Office of Science. The Annual Report includes summaries of recent significant and representative computational science projects conducted on NERSC systems as well as information about NERSC's current and planned systems and services.

  4. Annual Report 2000

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    The Institut Laue-Langevin (ILL) is an international research center using neutrons to probe the microscopic structure and dynamics of a broad range of materials. This annual report presents the ILL activities in 2000: the scientific highlights, the Millennium programme and the new developments, the workshops organized by the ILL, the experimental programme and the publications. (A.L.B.)

  5. FSAI Annual Report 2015

    OpenAIRE

    Food Safety Authority of Ireland

    2016-01-01

    THIS ANNUAL REPORT OUTLINES THE AUTHORITY’S EXTENSIVE WORK PROGRAMME IN 2015. IT DEMONSTRATES THE SIGNIFICANT ROLE THE AUTHORITY PLAYS IN ENCOURAGING THE HIGHEST STANDARDS IN FOOD PROVISION USING A COMBINATION OF SCIENCE BASED ACUMEN AND REGULATORY POWERS TO SAFEGUARD THE HEALTH AND INTERESTS OF CONSUMERS IN RELATION TO FOOD.

  6. Annual Integration Report 2013

    NARCIS (Netherlands)

    Jaco Dagevos; Willem Huijnk; Mérove Gijsberts

    2014-01-01

    Original title: Jaarrapport integratie 2013 The theme of the Annual Integration Report 2013 (Jaarrapport integratie 2013) is the participation of migrants on the labour market. The economic downturn is hitting the labour market hard. What does this mean for the labour market and income

  7. CSIR Annual report 1969

    CSIR Research Space (South Africa)

    CSIR

    1969-01-01

    Full Text Available This report presents the twenty fifth annual report of the Council for Scientific and Industrial Research. The report covers the period from the 1st January, 1969, to the 31st December 1969. Balance sheets and statements of income and expenditure...

  8. CSIR Annual report 1968

    CSIR Research Space (South Africa)

    CSIR

    1968-01-01

    Full Text Available This report presents the twenty fourth annual report of the Council for Scientific and Industrial Research. The report covers the period from the 1st January, 1968, to the 31st December 1968. Balance sheets and statements of income and expenditure...

  9. Annual report 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-10-01

    The annual report from IKU (Continental Shelf Institute) in Norway deals with the market adjustment of research activities at the institute as a result of offshore cost-cutting policy in the petroleum industry. The market is about to shift focus from volume to competence. In practice, that means buying competence instead of project ideas or proposals

  10. NRCC annual report, 1979

    Energy Technology Data Exchange (ETDEWEB)

    1980-11-01

    This annual report of the National Research for Computation in Chemistry (NRCC) Division describes the program of research workshops, software development, and scientific research of the Division in 1979. This year marked the first full calendar year of activity of the Division. Initial staffing in the core scientific areas was completed by the addition of a crystallographer.

  11. CSIR Annual report 1967

    CSIR Research Space (South Africa)

    CSIR

    1967-01-01

    Full Text Available This report presents the twenty third annual report of the Council for Scientific and Industrial Research. The report covers the period from the 1st January, 1967, to the 31st December 1967. Balance sheets and statements of income and expenditure...

  12. CSIR Annual report 1980

    CSIR Research Space (South Africa)

    CSIR

    1980-01-01

    Full Text Available This report presents the thirty-sixth annual report of the CSIR. The report covers the period 1 January, 1980 to 31 December 1980. A balance sheet and statements of income and expenditure for the financial year ended 31st March 1980, certified...

  13. CSIR Annual report 1970

    CSIR Research Space (South Africa)

    CSIR

    1970-01-01

    Full Text Available This report presents the twenty sixth annual report of the Council for Scientific and Industrial Research. The report covers the period from the 1st January, 1970, to the 31st December 1970. Balance sheets and statements of income and expenditure...

  14. CSIR Annual report 1971

    CSIR Research Space (South Africa)

    CSIR

    1971-01-01

    Full Text Available This report presents the twenty seventh annual report of the Council for Scientific and Industrial Research. The report covers the period from the 1st January, 1971, to the 31st December 1971. Balance sheets and statements of income and expenditure...

  15. NERSC Annual Report 2002

    Energy Technology Data Exchange (ETDEWEB)

    Hules, John

    2003-01-31

    The National Energy Research Scientific Computing Center (NERSC) is the primary computational resource for scientific research funded by the DOE Office of Science. The Annual Report for FY2002 includes a summary of recent computational science conducted on NERSC systems (with abstracts of significant and representative projects), and information about NERSC's current and planned systems and service

  16. CSIR Annual report 1983

    CSIR Research Space (South Africa)

    CSIR

    1983-01-01

    Full Text Available This report presents the thirty ninth annual report of the CSIR. The report covers the period 1 January, 1983 to 31 December 1983. A balance sheet and statements of income and expenditure for the financial year ended 31st March 1983, certified...

  17. CSIR Annual report 1962

    CSIR Research Space (South Africa)

    CSIR

    1962-01-01

    Full Text Available This report presents the eighteenth annual report of the CSIR. The report covers the period 1 January, 1962 to 31 December 1962. A balance sheet and statements of income and expenditure for the financial year ended 31st March 1962, certified...

  18. Carolinas Communication Annual, 1998.

    Science.gov (United States)

    McLennan, David B.

    1998-01-01

    This 1998 issue of "Carolinas Communication Annual" contains the following articles: "Give Me That Old Time Religion?: A Study of Religious Themes in the Rhetoric of the Ku Klux Klan" (John S. Seiter); "The Three Stooges versus the Third Reich" (Roy Schwartzman); "Interdisciplinary Team Teaching: Implementing…

  19. CSIR Annual report 1966

    CSIR Research Space (South Africa)

    CSIR

    1966-01-01

    Full Text Available This report presents the twenty second annual report of the Council for Scientific and Industrial Research. The report covers the period from the 1st January, 1966, to the 31st December 1966. Balance sheets and statements of income and expenditure...

  20. Mail Office annual closure

    CERN Multimedia

    2013-01-01

    On the occasion of the annual closure of CERN, there will be no mail distributed on Friday 20 December 2013 but mail will be collected in the morning. Nevertheless, you will still be able to bring your outgoing mail to Building 555-R-002 until 12 noon.  

  1. CSIR Annual report 1963

    CSIR Research Space (South Africa)

    CSIR

    1963-01-01

    Full Text Available This report presents the nineteenth annual report of the Council for Scientific and Industrial Research. The report covers the period from the 1st January, 1963, to the 31st December 1963. Balance sheets and statements of income and expenditure...

  2. NERSC Annual Report 2004

    Energy Technology Data Exchange (ETDEWEB)

    Hules, John; Bashor, Jon; Yarris, Lynn; McCullough, Julie; Preuss, Paul; Bethel, Wes

    2005-04-15

    The National Energy Research Scientific Computing Center (NERSC) is the premier computational resource for scientific research funded by the DOE Office of Science. The Annual Report includes summaries of recent significant and representative computational science projects conducted on NERSC systems as well as information about NERSC's current and planned systems and services.

  3. International Energy Annual, 1992

    Energy Technology Data Exchange (ETDEWEB)

    1994-01-14

    This report is prepared annually and presents the latest information and trends on world energy production and consumption for petroleum, natural gas, coal, and electricity. Trade and reserves are shown for petroleum, natural gas, and coal. Prices are included for selected petroleum products. Production and consumption data are reported in standard units as well as British thermal units (Btu) and joules.

  4. CSIR Annual report 1981

    CSIR Research Space (South Africa)

    CSIR

    1981-01-01

    Full Text Available This report presents the thirty seventh annual report of the CSIR. The report covers the period 1 January, 1981 to 31 December 1981. A balance sheet and statements of income and expenditure for the financial year ended 31st March 1981, certified...

  5. CSIR Annual report 1982

    CSIR Research Space (South Africa)

    CSIR

    1982-01-01

    Full Text Available This report presents the thirty eighth annual report of the CSIR. The report covers the period 1 January, 1982 to 31 December 1982. A balance sheet and statements of income and expenditure for the financial year ended 31st March 1982, certified...

  6. Comparison of aerosol optical properties at the sub-arctic stations ALOMAR-Andenes, Abisko and Sodankylä in late spring and summer 2007

    Science.gov (United States)

    Rodríguez, E.; Toledano, C.; Cachorro, V.; de Leeuw, G.; De Frutos, A.; Gausa, M.; Holben, B.

    2012-04-01

    Aerosol concentration and aerosol type, retrieved from observations with CIMEL sun-photometers at three sub-arctic locations at the Scandinavian Peninsula are presented. The observations were made at ALOMAR-Andenes in Norway, Abisko in Sweden and Sodankylä in Finland. This field campaign took place in late spring and summer 2007 as part of the activities of the International Polar Year (IPY) within the POLARCAT project at ALOMAR and Abisko. Aerosol properties were characterized using the relationship between the aerosol optical depth and the Ångström Exponent. The characteristics of the predominant aerosol type and microphysics are largely determined by the location of the site (continental or coastal). During summer the fine mode particles dominate, as indicated by the fine mode volume fraction and the Ångström Exponent. The aerosol concentration was on average very low, except during an event in which long-range transported aerosols (dust and pollution) were detected.

  7. The fate of 13C15N labelled glycine in permafrost and surface soil at simulated thaw in mesocosms from high arctic and subarctic ecosystems

    DEFF Research Database (Denmark)

    Ravn, Nynne Marie Rand; Elberling, Bo; Michelsen, Anders

    2017-01-01

    glycine addition. Results: Near-surface soil microbes were more efficient in the uptake of intact glycine immediately upon thaw than plants. After one month plants had gained more 15N whereas microbes seemed to lose 15N originating from glycine. We observed a time lag in glycine degradation upon...... compound in thawing permafrost and surface soil. Methods: Double labeled glycine (13C15N) was added to soil columns with vegetation and to permafrost. During thaw conditions ecosystem respiration 13C was measured and 13C and 15N distribution in the ecosystem pools was quantified one day and one month after...... permafrost thaw, in contrast to surface soil thaw. Conclusions: Our results suggest that both arctic plants and microorganisms acquire amino acids released upon spring and permafrost thaw. Despite indications of more efficient utilization of added substrate in the High Arctic than the Subarctic, we conclude...

  8. Impact of mining and refining on the distribution and accumulation of nickel and other heavy metals in sediments of subarctic Lake Kuetsjärvi, Murmansk Region, Russia.

    Science.gov (United States)

    Dauvalter, Vladimir

    2003-04-01

    Research on the influence of the activities of Pechenganickel Mining and Metallurgical Company on sediment heavy-metal geochemistry of the subarctic Lake Kuetsjärvi (north-western Russia) are described. It is estimated that during 60 years of mining/refining activity, 310 t of Ni, 120 t of Cu, 14 t of Co, 19 t of Zn, 0.087 t of Cd, 0.78 t of Pb and 0.053 t of Hg have accumulated in the lake sediments. The latter can be a source of secondary pollution and represent a danger for the lake ecosystem. The sedimentation rate in the lake is estimated to be within the range of 1.5-3 mm year(-1). The average concentrations of Ni, Cu, Hg and Co in superficial sediments have increased 25, 14, 11 and 5 times, respectively in the last century.

  9. Impact of decade-long warming, nutrient addition and shading on emission and carbon isotopic composition of CO2 from two subarctic dwarf shrub heaths

    DEFF Research Database (Denmark)

    Ravn, Nynne R.; Ambus, Per Lennart; Michelsen, Anders

    2017-01-01

    This study investigated ecosystem respiration, soil respiration and carbon isotopic composition in CO2 emitted from two subarctic shrub heaths with contrasting moisture regimes. The reported measurements were conducted 22 years (mesic heath) and 12 years (wet heath) upon initiation of in situ...... and soil respiration was measured using closed chambers and CO2 in the soil profile was sampled with gas probes installed at different depths. At the mesic heath ecosystem respiration was increased 46% by warming while soil respiration increased 133% by nutrient addition. At the wet heath, warming...... climate change related manipulations of temperature, nutrient availability and light. The aim was to quantify expected climatic change effects on soil and ecosystem respiration, and to investigate whether the emitted CO2 originates from old carbon stores in the soil or from newly fixed carbon. Ecosystem...

  10. Growing season CH4 and N2O fluxes from a subarctic landscape in northern Finland; from chamber to landscape scale

    Science.gov (United States)

    Dinsmore, Kerry J.; Drewer, Julia; Levy, Peter E.; George, Charles; Lohila, Annalea; Aurela, Mika; Skiba, Ute M.

    2017-02-01

    Subarctic and boreal emissions of CH4 are important contributors to the atmospheric greenhouse gas (GHG) balance and subsequently the global radiative forcing. Whilst N2O emissions may be lower, the much greater radiative forcing they produce justifies their inclusion in GHG studies. In addition to the quantification of flux magnitude, it is essential that we understand the drivers of emissions to be able to accurately predict climate-driven changes and potential feedback mechanisms. Hence this study aims to increase our understanding of what drives fluxes of CH4 and N2O in a subarctic forest/wetland landscape during peak summer conditions and into the shoulder season, exploring both spatial and temporal variability, and uses satellite-derived spectral data to extrapolate from chamber-scale fluxes to a 2 km × 2 km landscape area.From static chamber measurements made during summer and autumn campaigns in 2012 in the Sodankylä region of northern Finland, we concluded that wetlands represent a significant source of CH4 (3.35 ± 0.44 mg C m-2 h-1 during the summer campaign and 0.62 ± 0.09 mg C m-2 h-1 during the autumn campaign), whilst the surrounding forests represent a small sink (-0.06 ± weighted by forest/wetland proportion (0.99 ± 0.16, 0.93 ± 0.12 mg C m-2 h-1, respectively). Hence we conclude that ignoring the detailed spatial variability in CH4 emissions within a landscape leads to a potentially significant underestimation of landscape-scale fluxes. Given the small magnitude of measured N2O fluxes a similar level of detailed upscaling was not needed; we conclude that N2O fluxes do not currently comprise an important component of the landscape-scale GHG budget at this site.

  11. Effects of warming on CO2, N2O and CH4 fluxes and underlying processes from subarctic tundra, Northwest Russia

    Science.gov (United States)

    Voigt, Carolina; Lamprecht, Richard E.; Marushchak, Maija E.; Biasi, Christina; Martikainen, Pertti J.

    2014-05-01

    Peatlands, especially those located in the highly sensitive arctic and subarctic latitudes, are known to play a major role in the global carbon cycle. Predicted climatic changes - entailing an increase in near-surface temperature and a change in precipitation patterns - will most likely have a serious yet uncertain impact on the greenhouse gas (GHG) balance of these ecosystems. Microbial processes are enhanced by warmer temperatures which may lead to increased trace gas fluxes to the atmosphere. However, the response of ecosystem processes and related GHG fluxes may differ largely across the landscape depending on soil type, vegetation cover, and moisture conditions. In this study we investigate how temperature increase potentially reflects on GHG fluxes (CO2, CH4 and N2O) from various tundra surfaces in the Russian Arctic. These surfaces include raised peat plateau complexes, mineral tundra soils, bare surfaces affected by frost action such as peat circles and thermokarst lake walls, as well as wetlands. Predicted temperature increase and climate change effects are simulated by means of open top chambers (OTCs), which are placed on different soil types for the whole snow-free period. GHG fluxes, gas and nutrient concentrations in the soil profile, as well as supporting environmental parameters are monitored for the full growing season. Aim of the study is not only the quantification of aboveground GHG fluxes from the study area, but the linking of those to underlying biogeochemical processes in permafrost soils. Special emphasis is placed on the interface between active layer and old permafrost and its response to warming, since little is known about the lability of old carbon stocks made available through an increase in active layer depth. Overall goal of the study is to gain a better understanding of C and N cycling in subarctic tundra soils and to deepen knowledge in respect to carbon-permafrost feedbacks in respect to climate.

  12. Uncertainty assessment of a polygon database of soil organic carbon for greenhouse gas reporting in Canada’s Arctic and sub-arctic

    Directory of Open Access Journals (Sweden)

    M.F. Hossain

    2014-08-01

    Full Text Available Canada’s Arctic and sub-arctic consist 46% of Canada’s landmass and contain 45% of the total soil organic carbon (SOC. Pronounced climate warming and increasing human disturbances could induce the release of this SOC to the atmosphere as greenhouse gases. Canada is committed to estimating and reporting the greenhouse gases emissions and removals induced by land use change in the Arctic and sub-arctic. To assess the uncertainty of the estimate, we compiled a site-measured SOC database for Canada’s north, and used it to compare with a polygon database, that will be used for estimating SOC for the UNFCCC reporting. In 10 polygons where 3 or more measured sites were well located in each polygon, the site-averaged SOC content agreed with the polygon data within ±33% for the top 30 cm and within ±50% for the top 1 m soil. If we directly compared the SOC of the 382 measured sites with the polygon mean SOC, there was poor agreement: The relative error was less than 50% at 40% of the sites, and less than 100% at 68% of the sites. The relative errors were more than 400% at 10% of the sites. These comparisons indicate that the polygon database is too coarse to represent the SOC conditions for individual sites. The difference is close to the uncertainty range for reporting. The spatial database could be improved by relating site and polygon SOC data with more easily observable surface features that can be identified and derived from remote sensing imagery.

  13. Current temporal trends in moth abundance are counter to predicted effects of climate change in an assemblage of subarctic forest moths.

    Science.gov (United States)

    Hunter, Mark D; Kozlov, Mikhail V; Itämies, Juhani; Pulliainen, Erkki; Bäck, Jaana; Kyrö, Ella-Maria; Niemelä, Pekka

    2014-06-01

    Changes in climate are influencing the distribution and abundance of the world's biota, with significant consequences for biological diversity and ecosystem processes. Recent work has raised concern that populations of moths and butterflies (Lepidoptera) may be particularly susceptible to population declines under environmental change. Moreover, effects of climate change may be especially pronounced in high latitude ecosystems. Here, we examine population dynamics in an assemblage of subarctic forest moths in Finnish Lapland to assess current trajectories of population change. Moth counts were made continuously over a period of 32 years using light traps. From 456 species recorded, 80 were sufficiently abundant for detailed analyses of their population dynamics. Climate records indicated rapid increases in temperature and winter precipitation at our study site during the sampling period. However, 90% of moth populations were stable (57%) or increasing (33%) over the same period of study. Nonetheless, current population trends do not appear to reflect positive responses to climate change. Rather, time-series models illustrated that the per capita rates of change of moth species were more frequently associated negatively than positively with climate change variables, even as their populations were increasing. For example, the per capita rates of change of 35% of microlepidoptera were associated negatively with climate change variables. Moth life-history traits were not generally strong predictors of current population change or associations with climate change variables. However, 60% of moth species that fed as larvae on resources other than living vascular plants (e.g. litter, lichen, mosses) were associated negatively with climate change variables in time-series models, suggesting that such species may be particularly vulnerable to climate change. Overall, populations of subarctic forest moths in Finland are performing better than expected, and their populations

  14. Annual Site Environmental Report: 2005

    Energy Technology Data Exchange (ETDEWEB)

    sabba, d

    2007-02-03

    This report provides information about environmental programs during 2005 at the Stanford Linear Accelerator Center (SLAC). Seasonal activities that span calendar years are also included. Production of an annual site environmental report (ASER) is a requirement established by the United States Department of Energy (DOE) for all management and operating (M&O) contractors throughout the DOE complex. SLAC is a federally-funded research and development center with Stanford University as the M&O contractor. SLAC effectively applied environmental management in meeting the site's integrated safety and environmental management system (ISEMS) goals. For normal daily activities, all SLAC managers and supervisors are responsible for ensuring that proper procedures are followed so that: (1) Worker safety and health are protected; (2) The environment is protected; and (3) Compliance is ensured. Throughout 2005, SLAC focused on these activities through the SLAC management systems (described in Chapter 3). These systems were also the way SLAC approached implementing ''greening of the government'' initiatives such as Executive Order 13148. The management systems at SLAC are effective, supporting compliance with all relevant statutory and regulatory requirements. There were no reportable releases to the environment from SLAC operations during 2005. In addition, many improvements were continued during 2005, in waste minimization, recycling, stormwater drain system, groundwater restoration, and implementing a chemical management system (CMS) to better manage chemical use. Program-specific details are discussed.

  15. Spring bloom dynamics in a subarctic fjord influenced by tidewater outlet glaciers (Godthåbsfjord, SW Greenland)

    NARCIS (Netherlands)

    Meire, L.; Mortensen, J.; Rysgaard, S.; Bendtsen, J.; Boone, W.; Meire, P.; Meysman, F.J.R.

    2016-01-01

    In high-latitude fjord ecosystems, the spring bloom accounts for a major part of the annual primary production and thus provides a crucial energy supply to the marine food web. However, the environmental factors that control the timing and intensity of these spring blooms remain uncertain. In 2013,

  16. 1988 Annual water management plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Ruby Lake NWR 1987 Annual Water Management Report 1988 Annual Water Management Plan. Includes 1987 weather summary, water availability forecast, summary of 1987...

  17. Density dependence and phenological mismatch: consequences for growth and survival of sub-arctic nesting Canada Geese

    Science.gov (United States)

    Brook, Rodney W.; Leafloor, James O.; Douglas, David C.; Abraham, Kenneth F.

    2015-01-01

    The extent to which species are plastic in the timing of their reproductive events relative to phenology suggests how change might affect their demography. An ecological mismatch between the timing of hatch for avian species and the peak availability in quality and quantity of forage for rapidly growing offspring might ultimately affect recruitment to the breeding population unless individuals can adjust the timing of breeding to adapt to changing phenology. We evaluated effects of goose density, hatch timing relative to forage plant phenology, and weather indices on annual growth of pre-fledging Canada geese (Branta canadensis) from 1993-2010 at Akimiski Island, Nunavut. We found effects of both density and hatch timing relative to forage plant phenology; the earlier that eggs hatched relative to forage plant phenology, the larger the mean gosling size near fledging. Goslings were smallest in years when hatch was latest relative to forage plant phenology, and when local abundance of breeding adults was highest. We found no evidence for a trend in relative hatch timing, but it was apparent that in early springs, Canada geese tended to hatch later relative to vegetation phenology, suggesting that geese were not always able to adjust the timing of nesting as rapidly as vegetation phenology was advanced. Analyses using forage biomass information revealed a positive relationship between gosling size and per capita biomass availability, suggesting a causal mechanism for the density effect. The effects of weather parameters explained additional variation in mean annual gosling size, although total June and July rainfall had a small additive effect on gosling size. Modelling of annual first year survival probability using mean annual gosling size as an annual covariate revealed a positive relationship, suggesting that reduced gosling growth negatively impacts recruitment.

  18. Density dependence and phenological mismatch: consequences for growth and survival of sub-arctic nesting Canada Geese

    Directory of Open Access Journals (Sweden)

    Rodney W. Brook

    2015-06-01

    Full Text Available The extent to which species are plastic in the timing of their reproductive events relative to phenology suggests how climate change might affect their demography. An ecological mismatch between the timing of hatch for avian species and the peak availability in quality and quantity of forage for rapidly growing offspring might ultimately affect recruitment to the breeding population unless individuals can adjust the timing of breeding to adapt to changing phenology. We evaluated effects of goose density, hatch timing relative to forage plant phenology, and weather indices on annual growth of pre-fledging Canada geese (Branta canadensis from 1993-2010 at Akimiski Island, Nunavut. We found effects of both density and hatch timing relative to forage plant phenology; the earlier that eggs hatched relative to forage plant phenology, the larger the mean gosling size near fledging. Goslings were smallest in years when hatch was latest relative to forage plant phenology, and when local abundance of breeding adults was highest. We found no evidence for a trend in relative hatch timing, but it was apparent that in early springs, Canada geese tended to hatch later relative to vegetation phenology, suggesting that geese were not always able to adjust the timing of nesting as rapidly as vegetation phenology was advanced. Analyses using forage biomass information revealed a positive relationship between gosling size and per capita biomass availability, suggesting a causal mechanism for the density effect. The effects of weather parameters explained additional variation in mean annual gosling size, although total June and July rainfall had a small additive effect on gosling size. Modelling of annual first-year survival probability using mean annual gosling size as an annual covariate revealed a positive relationship, suggesting that reduced gosling growth negatively impacts recruitment.

  19. The Oak Ridge Reservation Annual Site Environmental Report Summary, 2007

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2009-02-28

    The Oak Ridge Reservation Annual Site Environmental Report is prepared and published each year to inform the public of the environmental activities that take place on the reservation and in the surrounding areas. It is written to comply with DOE Order 231.1A, Environment, Safety, and Health Reporting. This document has been prepared to present the highlights of the Oak Ridge Reservation Annual Site Environmental Report 2007 in an easy-to-read, summary format.

  20. The Occurrence of Environmental Disclosures in the Annual Reports

    OpenAIRE

    Susi, Susi

    2009-01-01

    This study aims to evaluate whether the occurrence of environmental disclosures in a corporate annual report is associated with a firm environmental visibility. As environmentally visible firms are easier to observe by relevant constituents, they are more vulnerable to public scrutiny. This paper hypothesizes that environmentally visible firms tend to disclose environ-mental information in their annual reports as compared to those of less visible companies. A firm's environmental visibility i...

  1. Coal industry annual 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-01

    Coal Industry Annual 1997 provides comprehensive information about US coal production, number of mines, prices, productivity, employment, productive capacity, and recoverable reserves. US Coal production for 1997 and previous years is based on the annual survey EIA-7A, Coal Production Report. This report presents data on coal consumption, coal distribution, coal stocks, coal prices, and coal quality for Congress, Federal and State agencies, the coal industry, and the general public. Appendix A contains a compilation of coal statistics for the major coal-producing States. This report includes a national total coal consumption for nonutility power producers that are not in the manufacturing, agriculture, mining, construction, or commercial sectors. 14 figs., 145 tabs.

  2. International energy annual 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-04-01

    The International Energy Annual presents an overview of key international energy trends for production, consumption, imports, and exports of primary energy commodities in over 220 countries, dependencies, and areas of special sovereignty. Also included are population and gross domestic product data, as well as prices for crude oil and petroleum products in selected countries. Renewable energy reported in the International Energy Annual includes hydroelectric power and geothermal, solar, and wind electric power. Also included are biomass electric power for Brazil and the US, and biomass, geothermal, and solar energy produced in the US and not used for electricity generation. This report is published to keep the public and other interested parties fully informed of primary energy supplies on a global basis. The data presented have been largely derived from published sources. The data have been converted to units of measurement and thermal values (Appendices E and F) familiar to the American public. 93 tabs.

  3. NAGRA Annual report 2010

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-04-15

    This annual report presents the highlights of the activities carried out by the Swiss National Co-operative for the Disposal of Radioactive Wastes NAGRA during the year 2010. These include reviews by various commissions of the NAGRA co-operative's proposals for possible sites for nuclear waste repositories. Also, the enhancements made concerning information facilities for the general public at the co-operative's rock laboratories are mentioned. The operation of initial satellite-based precision measurement systems for movements in the earth's crust is noted. Organisational aspects and international co-operation are discussed. This annual report also looks at NAGRA's organisational structures and its commercial accounts. Appendices provide details on waste inventories and volumes and publications made in 2010. A selection of relevant internet addresses is also provided

  4. Renewable energy annual 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-01

    The Renewable Energy Annual 1995 is the first in an expected series of annual reports the Energy Information Administration (EIA) intends to publish to provide a comprehensive assessment of renewable energy. This report presents the following information on the history, status, and prospects of renewable energy data: estimates of renewable resources; characterizations of renewable energy technologies; descriptions of industry infrastructures for individual technologies; evaluations of current market status; and assessments of near-term prospects for market growth. An international section is included, as well as two feature articles that discuss issues of importance for renewable energy as a whole. The report also contains a number of technical appendices and a glossary. The renewable energy sources included are biomass (wood), municipal solid waste, biomass-derived liquid fuels, geothermal, wind, and solar and photovoltaic.

  5. Annual General Asssembly

    CERN Multimedia

    2005-01-01

    All members and beneficiaries of the Pension Fund are invited to attend the Annual General Asssembly to be held in the CERN Council Chamber on Thursday 13 October 2005 at 14:30 The Agenda comprises: Opening Remarks (J. Bezemer) Results and presentation of the Annual Report 2004 - Role of asset classes in pension funds (C. Cuénoud) Copies of the 2004 Report are available from departmental secretariats. Package of measures aiming at equilibrating the Fund - Proposals by the Governing Board (J.-P. Matheys) Questions from members and beneficiaries Persons wishing to ask questions are encouraged to submit them, where possible, in writing in advance, addressed to Mr C. Cuénoud, Administrator of the Fund. Conclusions (J. Bezemer) As usual, participants are invited to drinks after the assembly. NB The minutes of the 2004 General Assembly are available from the Administration of the Fund (tel.(+4122)767 27 42; e-mail Sophia.Revol@cern.ch)

  6. Annual General Asssembly

    CERN Multimedia

    Pension Fund

    2005-01-01

    All members and beneficiaries of the Pension Fund are invited to attend the Annual General Asssembly to be held in the CERN Council Chamber on Thursday 13 October 2005 at 14:30 The Agenda comprises: Opening Remarks (J. Bezemer) Results and presentation of the Annual Report 2004 - Role of asset classes in pension funds (C. Cuénoud). Copies of the 2004 Report are available from departmental secretariats. Package of measures aiming at equilibrating the Fund - Proposals by the Governing Board (J.-P. Matheys). Questions from members and beneficiaries. Persons wishing to ask questions are encouraged to submit them, where possible, in writing in advance, addressed to Mr C. Cuénoud, Administrator of the Fund. Conclusions (J. Bezemer). As usual, participants are invited to drinks after the assembly. NB The minutes of the 2004 General Assembly are available from the Administration of the Fund (tel.(+4122)767 27 42; e-mail Sophia.Revol@cern.ch)

  7. Annual report 1991

    Energy Technology Data Exchange (ETDEWEB)

    Broda, R.; Lesniak, L.; Malecki, P.; Stachura, Z.; Wojciechowski, H. [eds.

    1992-12-31

    The material presented describing the scientific activities of the Henryk Niewodniczanski Institute of Nuclear Physics in 1991 is the first annual report in several years.The arrangement of the report from various departments reflect the present structure of the Institute and is meant to help in the future task of reconstructing the Institute. Few guidelines proposed by the editorial board gave the individual departments much freedom in selecting the material and choosing the volume and format of presentation. (author).

  8. 2008 annual merit review

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2009-01-18

    The 2008 DOE Vehicle Technologies Program Annual Merit Review was held February 25-28, 2008 in Bethesda, Maryland. The review encompassed all of the work done by the Vehicle Technologies Program: a total of 280 individual activities were reviewed, by a total of just over 100 reviewers. A total of 1,908 individual review responses were received for the technical reviews, and an additional 29 individual review responses were received for the plenary session review.

  9. TIARA annual report 1997

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Ryuichi; Saido, Masahiro; Nashiyama, Isamu [eds.] [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment] [and others

    1998-10-01

    This annual report describes research activities which have been performed with the JAERI TIARA (Takasaki Ion Accelerators for Advanced Radiation Application) facilities from April 1, 1997 to March 31, 1998. Summary reports of 90 papers and brief descriptions on the status of TIARA in the period are contained. A list of publications, the type of research collaborations and organization of TIARA are also given as appendices. (author)

  10. TIARA annual report 1998

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-10-01

    This annual report describes research and development activities which have been performed with the JAERI TIARA (Takasaki Ion Accelerators for Advanced Radiation Application) facilities from April 1, 1998 to March 31, 1999. Summary reports of 95 papers and brief descriptions on the status of TIARA in the period are contained. A list of publications, the type of research collaborations and organization of TIARA are also given as appendices. (author)

  11. NSLS annual report 1984

    Energy Technology Data Exchange (ETDEWEB)

    Klaffky, R.; Thomlinson, W. (eds.)

    1984-01-01

    The first comprehensive Annual Report of the National Synchrotron Light Source comes at a time of great activity and forward motion for the facility. In the following pages we outline the management changes that have taken place in the past year, the progress that has been made in the commissioning of the x-ray ring and in the enhanced utilization of the uv ring, together with an extensive discussion of the interesting scientific experiments that have been carried out.

  12. TIARA annual report 2000

    Energy Technology Data Exchange (ETDEWEB)

    Saidoh, Masahiro; Toraishi, Akio; Namba, Hideki (eds.) [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment] [and others

    2001-11-01

    This annual report describes research and development activities which have been performed with the JAERI TIARA (Takasaki Ion Accelerators for Advanced Radiation Application) facilities from April 1, 2000 to March 31, 2001. Summary reports of 103 papers and brief descriptions on the status of TIARA in the period are contained. A list of publications, the type of research collaborations and organization of TIARA are also given as appendices. (author)

  13. TIARA annual report 2001

    Energy Technology Data Exchange (ETDEWEB)

    Saidoh, Masahiro; Ohara, Yoshihiro; Namba, Hideki (eds.) [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment] [and others

    2002-11-01

    This annual report describes research and development activities which have been performed with the JAERI TIARA (Takasaki Ion Accelerators for Advanced Radiation Application) facilities from April 1, 2001 to March 31, 2002. Summary reports of 109 papers and brief descriptions on the status of TIARA in the period are contained. A list of publications, the type of research collaborations and organization of TIARA are also given as appendices. (author)

  14. TIARA annual report 1999

    Energy Technology Data Exchange (ETDEWEB)

    Saidoh, Masahiro; Toraishi, Akio; Itoh, Hisayoshi [eds.] [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment] [and others

    2000-10-01

    This annual report describes research and development activities which have been performed with the JAERI TIARA (Takasaki Ion Accelerators for Advanced Radiation Application) facilities from April 1, 1999 to March 31, 2000. Summary reports of 106 papers and brief descriptions on the status of TIARA in the period are contained. A list of publications, the type of research collaborations and organization of TIARA are also given as appendices. (author)

  15. NERSC 1998 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Hules, John (ed.)

    1999-03-01

    This 1998 annual report from the National Scientific Energy Research Computing Center (NERSC) presents the year in review of the following categories: Computational Science; Computer Science and Applied Mathematics; and Systems and Services. Also presented are science highlights in the following categories: Basic Energy Sciences; Biological and Environmental Research; Fusion Energy Sciences; High Energy and Nuclear Physics; and Advanced Scientific Computing Research and Other Projects.

  16. TIARA annual report 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-11-01

    This annual report describes research activities which have been performed with the JAERI TIARA (Takasaki Ion Accelerators for Advanced Radiation Application) facilities from April 1, 1996 to March 31, 1997. Summary reports of 88 papers and 4 brief descriptions on the status of TIARA in the period are contained. A list of publications, the type of research collaborations and organization of TIARA are also given as appendices. (J.P.N.)

  17. 2012 CPES Annual Report

    OpenAIRE

    Virginia Tech. Center for Power Electronics Systems

    2012-01-01

    The Center for Power Electronics Systems at Virginia Tech is a research center dedicated to improving electrical power processing and distribution that impact systems of all sizes – from battery – operated electronics to vehicles to regional and national electrical distribution systems. Our mission is to provide leadership through global collaborative research and education for creating advanced electric power processing systems of the highest value to society. CPES, with annual research expe...

  18. Uranium industry annual 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-05

    The Uranium Industry Annual 1994 (UIA 1994) provides current statistical data on the US uranium industry`s activities relating to uranium raw materials and uranium marketing during that survey year. The UIA 1994 is prepared for use by the Congress, Federal and State agencies, the uranium and nuclear electric utility industries, and the public. It contains data for the 10-year period 1985 through 1994 as collected on the Form EIA-858, ``Uranium Industry Annual Survey.`` Data collected on the ``Uranium Industry Annual Survey`` (UIAS) provide a comprehensive statistical characterization of the industry`s activities for the survey year and also include some information about industry`s plans and commitments for the near-term future. Where aggregate data are presented in the UIA 1994, care has been taken to protect the confidentiality of company-specific information while still conveying accurate and complete statistical data. A feature article, ``Comparison of Uranium Mill Tailings Reclamation in the United States and Canada,`` is included in the UIA 1994. Data on uranium raw materials activities including exploration activities and expenditures, EIA-estimated resources and reserves, mine production of uranium, production of uranium concentrate, and industry employment are presented in Chapter 1. Data on uranium marketing activities, including purchases of uranium and enrichment services, and uranium inventories, enrichment feed deliveries (actual and projected), and unfilled market requirements are shown in Chapter 2.

  19. Annual report 1999 - Brazil Nuclear Industry (INB); Relatorio anual 1999 - Industrias Nucleares do Brasil S.A

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    This document presents the 1999 annual report covering the following activities: nuclear fuel, resources and application, ISO 9001, environment social activities, personnel, financial indicators, and countability.

  20. Sphagnum-dwelling testate amoebae in subarctic bogs are more sensitive to soil warming in the growing season than in winter: the results of eight-year field climate manipulations.

    Science.gov (United States)

    Tsyganov, Andrey N; Aerts, Rien; Nijs, Ivan; Cornelissen, Johannes H C; Beyens, Louis

    2012-05-01

    Sphagnum-dwelling testate amoebae are widely used in paleoclimate reconstructions as a proxy for climate-induced changes in bogs. However, the sensitivity of proxies to seasonal climate components is an important issue when interpreting proxy records. Here, we studied the effects of summer warming, winter snow addition solely and winter snow addition together with spring warming on testate amoeba assemblages after eight years of experimental field climate manipulations. All manipulations were accomplished using open top chambers in a dry blanket bog located in the sub-Arctic (Abisko, Sweden). We estimated sensitivity of abundance, diversity and assemblage structure of living and empty shell assemblages of testate amoebae in the living and decaying layers of Sphagnum. Our results show that, in a sub-arctic climate, testate amoebae are more sensitive to climate changes in the growing season than in winter. Summer warming reduced species richness and shifted assemblage composition towards predominance of xerophilous species for the living and empty shell assemblages in both layers. The higher soil temperatures during the growing season also decreased abundance of empty shells in both layers hinting at a possible increase in their decomposition rates. Thus, although possible effects of climate changes on preservation of empty shells should always be taken into account, species diversity and structure of testate amoeba assemblages in dry subarctic bogs are sensitive proxies for climatic changes during the growing season. Copyright © 2011 Elsevier GmbH. All rights reserved.

  1. The SRTR/OPTN Annual Data Report

    Science.gov (United States)

    ... Annual Data Report The SRTR/OPTN Annual Data Report Statistics on donation and transplantation in the United ... US in 2015. The SRTR/OPTN Annual Data Report SRTR/OPTN Annual Data Report Learn more from ...

  2. NERSC 2001 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    Hules, John (editor)

    2001-12-12

    The National Energy Research Scientific Computing Center (NERSC) is the primary computational resource for scientific research funded by the DOE Office of Science. The Annual Report for FY2001 includes a summary of recent computational science conducted on NERSC systems (with abstracts of significant and representative projects); information about NERSC's current systems and services; descriptions of Berkeley Lab's current research and development projects in applied mathematics, computer science, and computational science; and a brief summary of NERSC's Strategic Plan for 2002-2005.

  3. Nordel annual report 2003

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-06-01

    Nordel is a body for co-operation between the transmission system operators (TSO's) in Denmark, Finland, Iceland, Norway and Sweden with the primary objective to create conditions for and develop an efficient and harmonised Nordic electricity market, regardless of national borders. Furthermore, Nordel serves as forum for contact between the TSOs and representatives of the market players in the Nordic countries. The statistical part of Nordel's annual report includes data about: Exchange of electricity; Gross consumption; Electricity generation; Installed capacity; Generation of condensing power; Net consumption; Transmission capacity; Pumped storage power; Losses; Occasional power to electric boilers; Total consumption; CHP generation. (BA)

  4. Annual Energy Review 2001

    Energy Technology Data Exchange (ETDEWEB)

    Seiferlein, Katherine E. [USDOE Energy Information Administration (EIA), Washington, DC (United States)

    2002-11-01

    The Annual Energy Review (AER) is a statistical history of energy activities in the United States. It documents trends and milestones in U.S. energy production, trade, storage, pricing, and consumption. Each new year of data that is added to the time series—which now reach into 7 decades—extends the story of how Americans have acquired and used energy. It is a story of continual change as the Nation's economy grew, energy requirements expanded, resource availability shifted, and interdependencies developed among nations.

  5. Annual Energy Review 2010

    Energy Technology Data Exchange (ETDEWEB)

    None

    2011-10-01

    This twenty-ninth edition of the Annual Energy Review (AER) presents the U.S. Energy Information Administration’s (EIA) most comprehensive look at integrated energy statistics. The summary statistics on the Nation’s energy production, consumption, trade, stocks, and prices cover all major energy commodities and all energy-consuming sectors of the U.S. economy from 1949 through 2010. The AER is EIA’s historical record of energy statistics and, because the coverage spans six decades, the statistics in this report are well-suited to long-term trend analysis.

  6. International energy annual 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    The International Energy Annual presents information and trends on world energy production and consumption for petroleum, natural gas, coal, and electricity. Production and consumption data are reported in standard units as well as British thermal units (Btu). Trade and reserves are shown for petroleum, natural gas, and coal. Data are provided on crude oil refining capacity and electricity installed capacity by type. Prices are included for selected crude oils and for refined petroleum products in selected countries. Population and Gross Domestic Product data are also provided.

  7. Renewable energy annual 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    This report presents summary data on renewable energy consumption, the status of each of the primary renewable technologies, a profile of each of the associated industries, an analysis of topical issues related to renewable energy, and information on renewable energy projects worldwide. It is the second in a series of annual reports on renewable energy. The renewable energy resources included in the report are biomass (wood and ethanol); municipal solid waste, including waste-to-energy and landfill gas; geothermal; wind; and solar energy, including solar thermal and photovoltaic. The report also includes various appendices and a glossary.

  8. NPL 1999 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    None

    2000-01-01

    OAK-B135 NPL 1999 Annual Report. The Nuclear Physics Laboratory at the University of Washington in Seattle pursues a broad program of nuclear physics research. Research activities are conducted locally and at remote sites. The current program includes ''in-house'' research on nuclear collisions using the local tandem Van de Graaff and superconducting linac accelerators as well as local and remote non-accelerator research on fundamental symmetries and weak interactions and user-mode research on relativistic heavy ions at large accelerator facilities around the world.

  9. Annual report to Congress

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-03-01

    This is the eighth annual report submitted by the Office of Civilian Radioactive Waste Management (OCRWM) to Congress. It covers activities and expenditures during Fiscal Year 1991, which ended September 30, 1991. Chapter 1 of this report describes OCRWM`s mission and objectives. Chapters 2 through 8 cover the following topics: earning public trust and confidence; geological disposal; monitored retrieval storage; transportation; systems integration and regulatory compliance; international programs; and program management. Financial statements for the Nuclear Waste Fund are presented in Chapter 9.

  10. Annual Site Environmental Report: 2002

    Energy Technology Data Exchange (ETDEWEB)

    Nuckolls, H.; /SLAC

    2006-04-19

    This report provides information about environmental programs during 2002 at the Stanford Linear Accelerator Center (SLAC). Seasonal activities that span calendar years are also included. Production of an annual site environmental report (ASER) is a requirement established by the United States Department of Energy (DOE) for all management and operating (M&O) contractors throughout the DOE complex. SLAC is a federally-funded, research and development center with Stanford University as the M&O contractor. The most noteworthy information in this report is summarized in this section. This summary demonstrates the effective application of SLAC environmental management in meeting the site's integrated safety management system (ISMS) goals. For normal daily activities, all SLAC managers and supervisors are responsible for ensuring that proper procedures are followed so that worker safety and health are protected; the environment is protected; and compliance is ensured. Throughout 2002, SLAC focused on these activities through the SLAC management systems (described in Chapter 3). These systems were also the way SLAC approached implementing ''greening of the government'' initiatives such as Executive Order 13148. The management systems at SLAC are effective, supporting compliance with all relevant statutory and regulatory requirements. SLAC did not receive any notices of violation during 2002. In addition, many improvements were continued during 2002, in decreasing air emission rates, the storm drain system, groundwater restoration, and planning for a chemical management system to manage chemical use better.

  11. ANNUAL GENERAL ASSEMBLY

    CERN Multimedia

    2001-01-01

    All members and beneficiaries of the Pension Fund are invited to attend the Annual General Asssembly to be held in the CERN Auditorium on Wednesday 3 October 2001 at 14.30 hrs The Agenda comprises:   Opening Remarks (P. Levaux) Some aspects of risk in a pension fund (C. Cuénoud) Annual Report 2000: Presentation and results (C. Cuénoud) Copies of the Report are available from divisional secretariats. Results of the actuarial reviews (G. Maurin) Questions from members and beneficiaries Persons wishing to ask questions are encouraged to submit them, where possible, in writing in advance, addressed to Mr C. Cuénoud, Administrator of the Fund. Conclusions (P. Levaux) As usual, participants are invited to drinks after the assembly. NB The minutes of the 2000 General Assembly are available from the Administration of the Fund (tel. + 41 22 767 91 94; e-mail Graziella.Praire@cern.ch) The English version will be published next week.

  12. Annual Energy Review 1993

    Energy Technology Data Exchange (ETDEWEB)

    1994-07-14

    This twelfth edition of the Annual Energy Review (AER) presents the Energy Information Administration`s historical energy statistics. For most series, statistics are given for every year from 1949 through 1993. Because coverage spans four and a half decades, the statistics in this report are well-suited to long-term trend analyses. The AER is comprehensive. It covers all major energy activities, including consumption, production, trade, stocks, and prices, for all major energy commodities, including fossil fuels and electricity. The AER also presents Energy Information Administration (EIA) statistics on some renewable energy sources. EIA estimates that its consumption series include about half of the renewable energy used in the United States. For a more complete discussion of EIA`s renewables data, see p. xix, ``Introducing Expanded Coverage of Renewable Energy Data Into the Historical Consumption Series.`` Copies of the 1993 edition of the Annual Energy Review may be obtained by using the order form in the back of this publication. Most of the data in the 1993 edition also are available on personal computer diskette. For more information about the diskettes, see the back of this publication. In addition, the data are available as part of the National Economic, Social, and Environmental Data Bank on a CD-ROM. For more information about the data bank, contact the US Department of Commerce Economics and Statistics Administration, on 202-482-1986.

  13. Electric power annual 1992

    Energy Technology Data Exchange (ETDEWEB)

    1994-01-06

    The Electric Power Annual presents a summary of electric utility statistics at national, regional and State levels. The objective of the publication is to provide industry decisionmakers, government policymakers, analysts and the general public with historical data that may be used in understanding US electricity markets. The Electric Power Annual is prepared by the Survey Management Division; Office of Coal, Nuclear, Electric and Alternate Fuels; Energy Information Administration (EIA); US Department of Energy. ``The US Electric Power Industry at a Glance`` section presents a profile of the electric power industry ownership and performance, and a review of key statistics for the year. Subsequent sections present data on generating capability, including proposed capability additions; net generation; fossil-fuel statistics; retail sales; revenue; financial statistics; environmental statistics; electric power transactions; demand-side management; and nonutility power producers. In addition, the appendices provide supplemental data on major disturbances and unusual occurrences in US electricity power systems. Each section contains related text and tables and refers the reader to the appropriate publication that contains more detailed data on the subject matter. Monetary values in this publication are expressed in nominal terms.

  14. Hydrology of the North Klondike River: carbon export, water balance and inter-annual climate influences within a sub-alpine permafrost catchment.

    Science.gov (United States)

    Lapp, Anthony; Clark, Ian; Macumber, Andrew; Patterson, Tim

    2017-10-01

    Arctic and sub-arctic watersheds are undergoing significant changes due to recent climate warming and degrading permafrost, engendering enhanced monitoring of arctic rivers. Smaller catchments provide understanding of discharge, solute flux and groundwater recharge at the process level that contributes to an understanding of how larger arctic watersheds are responding to climate change. The North Klondike River, located in west central Yukon, is a sub-alpine permafrost catchment, which maintains an active hydrological monitoring station with a record of >40 years. In addition to being able to monitor intra-annual variability, this data set allows for more complex analysis of streamflow records. Streamflow data, geochemistry and stable isotope data for 2014 show a groundwater-dominated system, predominantly recharged during periods of snowmelt. Radiocarbon is shown to be a valuable tracer of soil zone recharge processes and carbon sources. Winter groundwater baseflow contributes 20 % of total annual discharge, and accounts for up to 50 % of total river discharge during the spring and summer months. Although total stream discharge remains unchanged, mean annual groundwater baseflow has increased over the 40-year monitoring period. Wavelet analysis reveals a catchment that responds to El Niño and longer solar cycles, as well as climatic shifts such as the Pacific Decadal Oscillation. Dedicated to Professor Peter Fritz on the occasion of his 80th birthday.

  15. Ecosystem nitrogen fixation throughout the snow-free period in subarctic tundra: effects of willow and birch litter addition and warming.

    Science.gov (United States)

    Rousk, Kathrin; Michelsen, Anders

    2017-04-01

    Nitrogen (N) fixation in moss-associated cyanobacteria is one of the main sources of available N for N-limited ecosystems such as subarctic tundra. Yet, N2 fixation in mosses is strongly influenced by soil moisture and temperature. Thus, temporal scaling up of low-frequency in situ measurements to several weeks, months or even the entire growing season without taking into account changes in abiotic conditions cannot capture the variation in moss-associated N2 fixation. We therefore aimed to estimate moss-associated N2 fixation throughout the snow-free period in subarctic tundra in field experiments simulating climate change: willow (Salix myrsinifolia) and birch (Betula pubescens spp. tortuosa) litter addition, and warming. To achieve this, we established relationships between measured in situ N2 fixation rates and soil moisture and soil temperature and used high-resolution measurements of soil moisture and soil temperature (hourly from May to October) to model N2 fixation. The modelled N2 fixation rates were highest in the warmed (2.8 ± 0.3 kg N ha-1 ) and birch litter addition plots (2.8 ± 0.2 kg N ha-1 ), and lowest in the plots receiving willow litter (1.6 ± 0.2 kg N ha-1 ). The control plots had intermediate rates (2.2 ± 0.2 kg N ha-1 ). Further, N2 fixation was highest during the summer in the warmed plots, but was lowest in the litter addition plots during the same period. The temperature and moisture dependence of N2 fixation was different between the climate change treatments, indicating a shift in the N2 fixer community. Our findings, using a combined empirical and modelling approach, suggest that a longer snow-free period and increased temperatures in a future climate will likely lead to higher N2 fixation rates in mosses. Yet, the consequences of increased litter fall on moss-associated N2 fixation due to shrub expansion in the Arctic will depend on the shrub species' litter traits. © 2016 John Wiley & Sons Ltd.

  16. Ten-year trends of atmospheric mercury in the high Arctic compared to Canadian sub-Arctic and mid-latitude sites

    Directory of Open Access Journals (Sweden)

    A. S. Cole

    2013-02-01

    Full Text Available Global emissions of mercury continue to change at the same time as the Arctic is experiencing ongoing climatic changes. Continuous monitoring of atmospheric mercury provides important information about long-term trends in the balance between transport, chemistry, and deposition of this pollutant in the Arctic atmosphere. Ten-year records of total gaseous mercury (TGM from 2000 to 2009 were analyzed from two high Arctic sites at Alert (Nunavut, Canada and Zeppelin Station (Svalbard, Norway; one sub-Arctic site at Kuujjuarapik (Nunavik, Québec, Canada; and three temperate Canadian sites at St. Anicet (Québec, Kejimkujik (Nova Scotia and Egbert (Ontario. Five of the six sites examined showed a decreasing trend over this time period. Overall trend estimates at high latitude sites were: −0.9% yr−1 (95% confidence limits: −1.4, 0 at Alert and no trend (−0.5, +0.7 at Zeppelin Station. Faster decreases were observed at the remainder of the sites: −2.1% yr−1 (−3.1, −1.1 at Kuujjuarapik, −1.9% yr−1 (−2.1, −1.8 at St. Anicet, −1.6% yr−1 (−2.4, −1.0 at Kejimkujik and −2.2% yr−1 (−2.8, −1.7 at Egbert. Trends at the sub-Arctic and mid-latitude sites agree with reported decreases in background TGM concentration since 1996 at Mace Head, Ireland, and Cape Point, South Africa, but conflict with estimates showing an increase in global anthropogenic emissions over a similar period. Trends in TGM at the two high Arctic sites were not only less negative (or neutral overall but much more variable by season. Possible reasons for differences in seasonal and overall trends at the Arctic sites compared to those at lower latitudes are discussed, as well as implications for the Arctic mercury cycle. The first calculations of multi-year trends in reactive gaseous mercury (RGM and total particulate mercury (TPM at Alert were also performed, indicating increases from 2002 to 2009

  17. Relationships between Long-Term Demography and Weather in a Sub-Arctic Population of Common Eider.

    Directory of Open Access Journals (Sweden)

    Jón Einar Jónsson

    Full Text Available Effects of local weather on individuals and populations are key drivers of wildlife responses to climatic changes. However, studies often do not last long enough to identify weather conditions that influence demographic processes, or to capture rare but extreme weather events at appropriate scales. In Iceland, farmers collect nest down of wild common eider Somateria mollissima and many farmers count nests within colonies annually, which reflects annual variation in the number of breeding females. We collated these data for 17 colonies. Synchrony in breeding numbers was generally low between colonies. We evaluated 1 demographic relationships with weather in nesting colonies of common eider across Iceland during 1900-2007; and 2 impacts of episodic weather events (aberrantly cold seasons or years on subsequent breeding numbers. Except for episodic events, breeding numbers within a colony generally had no relationship to local weather conditions in the preceding year. However, common eider are sexually mature at 2-3 years of age and we found a 3-year time lag between summer weather and breeding numbers for three colonies, indicating a positive effect of higher pressure, drier summers for one colony, and a negative effect of warmer, calmer summers for two colonies. These findings may represent weather effects on duckling production and subsequent recruitment. Weather effects were mostly limited to a few aberrant years causing reductions in breeding numbers, i.e. declines in several colonies followed severe winters (1918 and some years with high NAO (1992, 1995. In terms of life history, adult survival generally is high and stable and probably only markedly affected by inclement weather or aberrantly bad years. Conversely, breeding propensity of adults and duckling production probably do respond more to annual weather variations; i.e. unfavorable winter conditions for adults increase probability of death or skipped breeding, whereas favorable summers

  18. Relationships between Long-Term Demography and Weather in a Sub-Arctic Population of Common Eider.

    Science.gov (United States)

    Jónsson, Jón Einar; Gardarsson, Arnthor; Gill, Jennifer A; Pétursdóttir, Una Krístín; Petersen, Aevar; Gunnarsson, Tómas Grétar

    2013-01-01

    Effects of local weather on individuals and populations are key drivers of wildlife responses to climatic changes. However, studies often do not last long enough to identify weather conditions that influence demographic processes, or to capture rare but extreme weather events at appropriate scales. In Iceland, farmers collect nest down of wild common eider Somateria mollissima and many farmers count nests within colonies annually, which reflects annual variation in the number of breeding females. We collated these data for 17 colonies. Synchrony in breeding numbers was generally low between colonies. We evaluated 1) demographic relationships with weather in nesting colonies of common eider across Iceland during 1900-2007; and 2) impacts of episodic weather events (aberrantly cold seasons or years) on subsequent breeding numbers. Except for episodic events, breeding numbers within a colony generally had no relationship to local weather conditions in the preceding year. However, common eider are sexually mature at 2-3 years of age and we found a 3-year time lag between summer weather and breeding numbers for three colonies, indicating a positive effect of higher pressure, drier summers for one colony, and a negative effect of warmer, calmer summers for two colonies. These findings may represent weather effects on duckling production and subsequent recruitment. Weather effects were mostly limited to a few aberrant years causing reductions in breeding numbers, i.e. declines in several colonies followed severe winters (1918) and some years with high NAO (1992, 1995). In terms of life history, adult survival generally is high and stable and probably only markedly affected by inclement weather or aberrantly bad years. Conversely, breeding propensity of adults and duckling production probably do respond more to annual weather variations; i.e. unfavorable winter conditions for adults increase probability of death or skipped breeding, whereas favorable summers can promote

  19. Annual variations in zooplankton from a polluted coastal environment

    Digital Repository Service at National Institute of Oceanography (India)

    Haridas, P.; Menon, P.G.; Madhupratap, M.

    . Copepods followed by cladocerans contributed to the bulk of zooplankton. Species composition of zooplankton and their ecology are discussed. Diversity of zooplankton was high in the postmonsoon months and also in April...

  20. 2011 Annual Report (National Defense Center for Energy and Environment)

    Science.gov (United States)

    2011-01-01

    Transition. Assessment (TRL 1-8) Development (TRL 1-5) Literature searches, data mining , surveys, and other methods are employed in this... coal . The NDCEE further improved the Onsite Field- feeding Waste to Energy Converter (OFWEC III), a WTE unit at the Natick Soldier Research... Reef and two legacy sites along the East Coast. In FY12 the NDCEE will continue to validate alternative processes and materials for sustainable

  1. National Defense Center for Energy and Environment 2008 Annual Report

    Science.gov (United States)

    2008-01-01

    A1116C as Maintenance Engineering Order AED A1116D, including the option to use starch graft acrylic polymer blast media (MIL- P-85891A, Type VII...crystallized cornstarch— an organic, nontoxic, biodegradable material. This environmentally friendly medium is most applicable to delicate substrates...where hand sanding and chemical wiping are used. CHP media meet military specification MIL-P-85891 for Type VII plastic media. Because of NDCEE

  2. Transportation statistics annual report 1996 : transportation and the environment

    Science.gov (United States)

    1996-01-01

    This report is a summary of the state of the nation's transportation systems and the issues and consequences of maintaining such a diverse and complex network. All transportation modes -- air, highway, rail, water, and pipeline -- are examined throug...

  3. National Defense Center for Energy and Environment 2009 Annual Report

    Science.gov (United States)

    2009-01-01

    on elimination of a methylene chloride -based paint stripping solvent currently utilized at ANAD. The NDCEE coordinated testing of three HAP-free...of coatings removal and de- painting , efforts were launched to find cost-effective chemical strippers that do not contain HAPs, specifically focusing... paint stripping solvents with ANAD and the Army Research Laboratory, MD. By switching to a HAP-free stripper , it is estimated that ANAD will reduce

  4. Areva, annual report 2004

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    This annual report contains information on AREVA objectives, prospects and strategies, particularly in chapters 4 and 7. This information is a not meant as a presentation of past performance data and should not be interpreted as a guarantee that events or data set forth herein are assured or that objectives will be met. Forward looking statements made in this document also address known and unknown risks, uncertainties and other factors that could, were they to translate into fact, cause AREVA future financial performance, operating performance and production to differ significantly from the objectives presented or suggested herein. Those factors include, in particular, changes in international, economic or market conditions, as well as risk factors presented in Section 4.14.3. Neither AREVA nor the AREVA group is committing to updating forward looking statements or information contained in the annual report. This annual report contains information on the markets, market shares and competitive position of the AREVA group. Unless otherwise indicated, all historical data and forward looking information are based on Group estimates (source: AREVA) and are provided as examples only. To AREVA knowledge, no report is available on the AREVA group markets that is sufficiently complete or objective to serve as a sole reference source. The AREVA group developed estimates based on several sources, including in-house studies and reports, statistics provided by international organizations and professional associations, data published by competitors and information collected by AREVA subsidiaries. The main sources, studies and reports used include (i) the International Atomic Energy Agency (IAEA), the International Energy Agency (IEA), the World Nuclear Association (WNA), the Nuclear Energy Institute (NEA), Nuclear Assurance Corporation (NAC), the European Atomic Energy Community (Euratom) and the Commissariat a l'Energie Atomique (CEA) for the nuclear business; and (ii

  5. Nuclear Physics Department annual report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-01

    This annual report presents articles and abstracts published in foreign journals, covering the following subjects: nuclear structure, nuclear reactions, applied physics, instrumentation, nonlinear phenomena and high energy physics

  6. The Medicare Annual Wellness Visit.

    Science.gov (United States)

    Colburn, Jessica L; Nothelle, Stephanie

    2018-02-01

    The Medicare Annual Wellness Visit is an annual preventive health benefit, which was created in 2011 as part of the Patient Protection and Affordable Care Act. The visit provides an opportunity for clinicians to review preventive health recommendations and screen for geriatric syndromes. In this article, the authors review the requirements of the Annual Wellness Visit, discuss ways to use the Annual Wellness Visit to improve the care of geriatric patients, and provide suggestions for how to incorporate this benefit into a busy clinic. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Acquisition Workforce Annual Report 2006

    Data.gov (United States)

    General Services Administration — This is the Federal Acquisition Institute's (FAI's) Annual demographic report on the Federal acquisition workforce, showing trends by occupational series, employment...

  8. Acquisition Workforce Annual Report 2008

    Data.gov (United States)

    General Services Administration — This is the Federal Acquisition Institute's (FAI's) Annual demographic report on the Federal acquisition workforce, showing trends by occupational series, employment...

  9. Canadian Petroleum Products Institute: Annual report 1991

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    Annual report of the Institute, which represents the refining and marketing sectors of the petroleum industry on environmental, health, safety, and business issues affecting the industry and Canadian society. The report describes the Institute; gives highlights for the year; describes the recipient of the first CPPI Chairman's Award, Dr. Linton Kulak; provides a general policy and guiding principles for environment, health, and safety; describes the environmental achievements and challenges of the Canadian petroleum industry; and describes industry economics and operations. A list of 1991 publications is also included.

  10. Uranium Industry Annual, 1992

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-28

    The Uranium Industry Annual provides current statistical data on the US uranium industry for the Congress, Federal and State agencies, the uranium and electric utility industries, and the public. The feature article, ``Decommissioning of US Conventional Uranium Production Centers,`` is included. Data on uranium raw materials activities including exploration activities and expenditures, resources and reserves, mine production of uranium, production of uranium concentrate, and industry employment are presented in Chapter 1. Data on uranium marketing activities including domestic uranium purchases, commitments by utilities, procurement arrangements, uranium imports under purchase contracts and exports, deliveries to enrichment suppliers, inventories, secondary market activities, utility market requirements, and uranium for sale by domestic suppliers are presented in Chapter 2.

  11. DANSYNC. Annual report 1996

    Energy Technology Data Exchange (ETDEWEB)

    Als-Nielsen, J.

    1997-02-01

    DANSYNC is an organisation of Danish users of hard X-ray synchrotron facilities, funded by The Danish Natural Science Research Council. It was founded in the beginning of 1996, and this is the first Annual Report from DANSYNC. Users span from basic physics at Risoe National Laboratory, Oersted Laboratory and Denmarks Technical University over materials science from Risoe National Laboratory to chemistry and biology at Aarhus University, Copenhagen University and Denmarks Technical University, as well as industrial research represented by Haldor Topsoee A/S and space research at Danish Space Research Institute. We do not have an X-ray synchrotron facility in Denmark, so all of this work is carried out at facilities abroad. Clearly the facility at DESY in Hamburg (HASYLAB and EMBL) is of the greatest significance for Danish synchrotron research. Home page: http://www.dansync.dk/dansync/. (LN).

  12. Nagra annual report 2007

    Energy Technology Data Exchange (ETDEWEB)

    Ammann, M. (ed.)

    2008-07-01

    This annual report issued by the Swiss National Cooperative for the Disposal of Radioactive Waste reviews the co-operative's activities in the year 2007 and presents an overview of developments in energy policy, planning procedures and funding plans. The selection of sites for the disposal of radioactive wastes in Switzerland is discussed. Various technical questions are briefly addressed and work being carried out in the rock laboratories in the Swiss Alps and Jura mountains is discussed. International co-operation is reviewed and public relations issues are discussed. Finally, organisational structures are described and the financial details for the year 2007 are presented. The report is completed with an appendix containing the co-operative's organigram, waste inventories and listings of publications, addresses and a short glossary.

  13. Nagra annual report 2008

    Energy Technology Data Exchange (ETDEWEB)

    Ammann, M. (ed.)

    2009-07-01

    This annual report issued by the Swiss National Co-operative for the Disposal of Radioactive Waste, Nagra, reviews the co-operative's activities in the year 2008 and presents an overview of developments in energy policy, planning procedures and funding plans. Energy policy and the selection of sites for the disposal of radioactive wastes in Switzerland are discussed. Various technical questions are briefly addressed and work being carried out in the rock laboratories in the Swiss Alps and Jura mountains is discussed. International co-operation is reviewed and public relations issues are discussed. Finally, organisational structures are described and Nagra's financial details for the year 2008 are presented and discussed. The report is completed with an appendix containing the co-operative's organigram, waste inventories and listings of publications, addresses and a short glossary.

  14. Coal industry annual 1993

    Energy Technology Data Exchange (ETDEWEB)

    1994-12-06

    Coal Industry Annual 1993 replaces the publication Coal Production (DOE/FIA-0125). This report presents additional tables and expanded versions of tables previously presented in Coal Production, including production, number of mines, Productivity, employment, productive capacity, and recoverable reserves. This report also presents data on coal consumption, coal distribution, coal stocks, coal prices, coal quality, and emissions for a wide audience including the Congress, Federal and State agencies, the coal industry, and the general public. In addition, Appendix A contains a compilation of coal statistics for the major coal-producing States. This report does not include coal consumption data for nonutility Power Producers who are not in the manufacturing, agriculture, mining, construction, or commercial sectors. This consumption is estimated to be 5 million short tons in 1993.

  15. Annual energy review 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    This 13th edition presents the Energy Information Administration`s historical energy statistics. For most series, statistics are given for every year from 1949 through 1994; thus, this report is well-suited to long-term trend analyses. It covers all major energy activities, including consumption, production, trade, stocks, and prices for all major energy commodities, including fossil fuels and electricity. Statistics on renewable energy sources are also included: this year, for the first time, usage of renewables by other consumers as well as by electric utilities is included. Also new is a two-part, comprehensive presentation of data on petroleum products supplied by sector for 1949 through 1994. Data from electric utilities and nonutilities are integrated as ``electric power industry`` data; nonutility power gross generation are presented for the first time. One section presents international statistics (for more detail see EIA`s International Energy Annual).

  16. Uranium industry annual 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-04-01

    The Uranium Industry Annual 1996 (UIA 1996) provides current statistical data on the US uranium industry`s activities relating to uranium raw materials and uranium marketing. The UIA 1996 is prepared for use by the Congress, Federal and State agencies, the uranium and nuclear electric utility industries, and the public. Data on uranium raw materials activities for 1987 through 1996 including exploration activities and expenditures, EIA-estimated reserves, mine production of uranium, production of uranium concentrate, and industry employment are presented in Chapter 1. Data on uranium marketing activities for 1994 through 2006, including purchases of uranium and enrichment services, enrichment feed deliveries, uranium fuel assemblies, filled and unfilled market requirements, uranium imports and exports, and uranium inventories are shown in Chapter 2. A feature article, The Role of Thorium in Nuclear Energy, is included. 24 figs., 56 tabs.

  17. 1994 MCAP annual report

    Energy Technology Data Exchange (ETDEWEB)

    Harmony, S.C.; Boyack, B.E.

    1995-04-01

    VELCOR is an integrated, engineering-level computer code that models the progression of severe accidents in light water reactor (LWR) nuclear power plants. The entire spectrum of severe accident phenomena, including reactor coolant system and containment thermal-hydraulic response, core heatup, degradation and relocation, and fission product release and transport is treated in MELCOR in a unified framework for both boiling water reactors (BWRs) and pressurized water reactors (PWRs). Its current uses include the estimation of severe accident source terms and their sensitivities and uncertainties in a variety of applications. Independent assessment efforts have been successfully completed by the US and international MELCOR user communities. Most of these independent assessment efforts have been conducted to support the needs and fulfill the requirements of the individual user organizations. The resources required to perform an extensive set of model and integral code assessments are large. A prudent approach to fostering code development and maturation is to coordinate the individual assessment efforts of the MELCOR user community. While retaining individual control over assessment resources, each organization using the MELCOR code could work with the other users to broaden assessment coverage and minimize duplication. In recognition of these considerations, the US Nuclear Regulatory Commission (US NRC) has initiated the MELCOR Cooperative Assessment Program (MCAP), a vehicle for coordinating and standardizing the assessment practices of the various MELCOR users. In addition, the user community will have a forum to better communicate lessons learned regarding MELCOR applications, capabilities, and user guidelines and limitations and to provide a user community perspective on code development needs and priorities. This second Annual Report builds on the foundation laid with the first Annual Report.

  18. Uptake of pulse injected nitrogen by soil microbes and mycorrhizal and non-mycorrhizal plants in a species-diverse subarctic heath ecosystem

    DEFF Research Database (Denmark)

    Andresen, Louise Christoffersen; Jonasson, Sven; Strom, Lena

    2008-01-01

    15N labeled ammonium, glycine or glutamic acid was injected into subarctic heath soil in situ, with the purpose of investigating how the nitrogen added in these pulses was subsequently utilized and cycled in the ecosystem. We analyzed the acquisition of 15N label in mycorrhizal and non-mycorrhiza......, the differences in 15N uptake patterns may also be due to differences in leaf longevity and woodiness between plant functional groups.......-mycorrhizal plants and in soil microorganisms, in order to reveal probable differences in acquisition patterns between the two functional plant types and between plants and soil microorganisms. Three weeks after the label addition, with the 15N-forms added with same amount of nitrogen per square meter, we analyzed...... the 15N-enrichment in total soil, in soil K2SO4 (0.5 M) extracts and in the microbial biomass after vacuum-incubation of soil in chloroform and subsequent K2SO4 extraction. Furthermore the 15N-enrichment was analyzed in current years leaves of the dominant plant species sampled three, five and 21 days...

  19. Flourish or flush: effects of simulated extreme rainfall events on Sphagnum-dwelling testate amoebae in a subarctic bog (Abisko, Sweden).

    Science.gov (United States)

    Tsyganov, Andrey N; Keuper, Frida; Aerts, Rien; Beyens, Louis

    2013-01-01

    Extreme precipitation events are recognised as important drivers of ecosystem responses to climate change and can considerably affect high-latitude ombrotrophic bogs. Therefore, understanding the relationships between increased rainfall and the biotic components of these ecosystems is necessary for an estimation of climate change impacts. We studied overall effects of increased magnitude, intensity and frequency of rainfall on assemblages of Sphagnum-dwelling testate amoebae in a field climate manipulation experiment located in a relatively dry subarctic bog (Abisko, Sweden). The effects of the treatment were estimated using abundance, species diversity and structure of living and empty shell assemblages of testate amoebae in living and decaying layers of Sphagnum. Our results show that increased rainfall reduced the mean abundance and species richness of living testate amoebae. Besides, the treatment affected species structure of both living and empty shell assemblages, reducing proportions of hydrophilous species. The effects are counterintuitive as increased precipitation-related substrate moisture was expected to have opposite effects on testate amoeba assemblages in relatively dry biotopes. Therefore, we conclude that other rainfall-related factors such as increased infiltration rates and frequency of environmental disturbances can also affect testate amoeba assemblages in Sphagnum and that hydrophilous species are particularly sensitive to variation in these environmental variables.

  20. CNP stoichiometry of a lipid-synthesising zooplankton, Calanus finmarchicus, from winter to spring bloom in a sub-Arctic sound

    Science.gov (United States)

    Aubert, A. B.; Svensen, C.; Hessen, D. O.; Tamelander, T.

    2013-02-01

    The aim of this study was to investigate the seasonal stoichiometry of the high-latitude lipid-synthesising copepod Calanus finmarchicus and assess how this would affect dietary demands with season, ontogeny and lipid storage. C:N:P ratios in different stages (adults, copepodite V and IV), in eggs and faecal pellets as well as in bulk food (seston) was analysed in a sub-Arctic Norwegian sound (69° 47'N, 19° 19'E) from late February to mid-May 2009. The period covered the phytoplankton bloom and was divided into four sequences of the bloom based on chl a and seston C:chl a ratio variations. The calculation of the somatic elemental C:N and C:P body ratios (without the lipid storage) indicates that nearly homeostatic control in C. finmarchicus is maintained in somatic tissues within stages, while not if the lipid storage pool is included. Nutrient limitation was assessed calculating threshold elemental ratios based on the somatic body ratios and for different sets of assimilation efficiencies, and indicated a predominant C limitation that may reflect demands for lipid storage. The results suggest that stoichiometric composition and demands in such high-latitude, lipid-storing species strongly depend on stage and season, and the large contribution of storage lipids highlights the need for a two-compartment approach for lipid-synthesising species, with different dietary requirements for somatic growth and for lipid storage.

  1. Temporal changes in community composition of heterotrophic bacteria during in situ iron enrichment in the western subarctic Pacific (SEEDS-II)

    Science.gov (United States)

    Kataoka, Takafumi; Suzuki, Koji; Hayakawa, Maki; Kudo, Isao; Higashi, Seigo; Tsuda, Atsushi

    2009-12-01

    Little is known about the effects of iron enrichment in high-nitrate low-chlorophyll (HNLC) waters on the community composition of heterotrophic bacteria, which are crucial to nutrient recycling and microbial food webs. Using denaturing gradient gel electrophoresis (DGGE) of 16S rDNA fragments, we investigated the heterotrophic eubacterial community composition in surface waters during an in situ iron-enrichment experiment (SEEDS-II) in the western subarctic Pacific in the summer of 2004. DGGE fingerprints representing the community composition of eubacteria differed inside and outside the iron-enriched patch. Sequencing of DGGE bands revealed that at least five phylotypes of α-proteobacteria including Roseobacter, Cytophaga-Flavobacteria- Bacteroides (CFB), γ-proteobacteria, and Actinobacteria occurred in almost all samples from the iron-enriched patch. Diatoms did not bloom during SEEDS-II, but the eubacterial composition in the iron-enriched patch was similar to that in diatom blooms observed previously. Although dissolved organic carbon (DOC) accumulation was not detected in surface waters during SEEDS-II, growth of the Roseobacter clade might have been particularly stimulated after iron additions. Two identified phylotypes of CFB were closely related to the genus Saprospira, whose algicidal activity might degrade the phytoplankton assemblages increased by iron enrichment. These results suggest that the responses of heterotrophic bacteria to iron enrichment could differ among phylotypes during SEEDS-II.

  2. Concentrations and cycling of DMS, DMSP, and DMSO in coastal and offshore waters of the Subarctic Pacific during summer, 2010-2011

    Science.gov (United States)

    Asher, Elizabeth; Dacey, John W.; Ianson, Debby; Peña, Angelica; Tortell, Philippe D.

    2017-04-01

    Concentrations of dimethylsulfide (DMS), measured in the Subarctic Pacific during summer 2010 and 2011, ranged from ˜1 to 40 nM, while dissolved dimethylsulfoxide (DMSO) concentrations (range 13-23 nM) exceeded those of dissolved dimethyl sulfoniopropionate (DMSP) (range 1.3-8.8 nM). Particulate DMSP dominated the reduced sulfur pool, reaching maximum concentrations of 100 nM. Coastal and off shore waters exhibited similar overall DMS concentration ranges, but sea-air DMS fluxes were lower in the oceanic waters due to lower wind speeds. Surface DMS concentrations showed statistically significant correlations with various hydrographic variables including the upwelling intensity (r2 = 0.52, p power at small scales. Stable isotope tracer experiments indicated that the DMSP cleavage pathway always exceeded the DMSO reduction pathway as a DMS source, leading to at least 85% more DMS production in each experiment. Gross DMS production rates were positively correlated with the upwelling intensity, while net rates of DMS production were significantly correlated to surface water DMS concentrations. This latter result suggests that our measurements captured dominant processes driving surface DMS accumulation across a coastal-oceanic gradient.

  3. RADMIL - eleventh annual report for 1996/97

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-01

    RADMIL is a local authority monitoring organisation which provides an effective and efficient means of investigating Lancashire`s radiological environment countrywide. This eleventh annual report covers the sources of radiation, radiological protection in the UK, environmental monitoring by government agencies and industry and an interpretation of the RADMIL monitoring results. (UK).

  4. 40 CFR 89.125 - Production engines, annual report.

    Science.gov (United States)

    2010-07-01

    ... produced by engine family, by gross power, by displacement, by fuel system, and, for engines produced under... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Production engines, annual report. 89... (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE NONROAD COMPRESSION-IGNITION ENGINES Emission Standards...

  5. Hazards Control Department 1996 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    Richards, J.

    1997-06-30

    This annual report on the activities of the Hazards Control Department (HCD) in 1996 is part of the department's continuing effort to foster a working environment at Lawrence Livermore National Laboratory where every person has the means, ability, and desire to work safely. The significant accomplishments and activities, the various services provided, and research into Environment, Safety, and Health (ES&H) issues by HCD would not have been possible without the many and ongoing contributions by its employees and support personnel. The HCD Leadership Team thanks each and every one in the department for their efforts and work in 1996 and for their personal commitment to keeping one of the premier research and scientific institutions in the world today a safe and healthy place.

  6. Annual rings in a native Hawaiian tree, Sophora chrysophylla, on Maunakea, Hawai‘i

    Science.gov (United States)

    Kainana S. Francisco; Patrick J. Hart; Jinbao Li; Edward R. Cook; Patrick J. Baker

    2015-01-01

    Annual rings are not commonly produced in tropical trees because they grow in a relatively aseasonal environment. However, in the subalpine zones of Hawai‘i's highest volcanoes, there is often strong seasonal variability in temperature and rainfall. Using classical dendrochronological methods, annual growth rings were shown to occur in Sophora...

  7. Seasonal sea ice cover as principal driver of spatial and temporal variation in depth extension and annual production of kelp in Greenland.

    Science.gov (United States)

    Krause-Jensen, Dorte; Marbà, Núria; Olesen, Birgit; Sejr, Mikael K; Christensen, Peter Bondo; Rodrigues, João; Renaud, Paul E; Balsby, Thorsten J S; Rysgaard, Søren

    2012-10-01

    We studied the depth distribution and production of kelp along the Greenland coast spanning Arctic to sub-Arctic conditions from 78 ºN to 64 ºN. This covers a wide range of sea ice conditions and water temperatures, with those presently realized in the south likely to move northwards in a warmer future. Kelp forests occurred along the entire latitudinal range, and their depth extension and production increased southwards presumably in response to longer annual ice-free periods and higher water temperature. The depth limit of 10% kelp cover was 9-14 m at the northernmost sites (77-78 ºN) with only 94-133 ice-free days per year, but extended to depths of 21-33 m further south (73 ºN-64 ºN) where >160 days per year were ice-free, and annual production of Saccharina longicruris and S. latissima, measured as the size of the annual blade, ranged up to sevenfold among sites. The duration of the open-water period, which integrates light and temperature conditions on an annual basis, was the best predictor (relative to summer water temperature) of kelp production along the latitude gradient, explaining up to 92% of the variation in depth extension and 80% of the variation in kelp production. In a decadal time series from a high Arctic site (74 ºN), inter-annual variation in sea ice cover also explained a major part (up to 47%) of the variation in kelp production. Both spatial and temporal data sets thereby support the prediction that northern kelps will play a larger role in the coastal marine ecosystem in a warmer future as the length of the open-water period increases. As kelps increase carbon-flow and habitat diversity, an expansion of kelp forests may exert cascading effects on the coastal Arctic ecosystem. © 2012 Blackwell Publishing Ltd.

  8. SKB Annual Report 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-05-01

    This is the annual report of the Swedish Nuclear Fuel and Waste Management Co (SKB). Part 1 of the report contains an overview of the SKB activities in different fields, and part 2 gives a description of the research and development work on nuclear waste disposal performed during 1996. Lectures and publications as well as reports issued during 1996 are listed in part 3, and summaries of the reports are listed in part 4. The task of SKB is to transport, store and dispose of the spent nuclear fuel and radioactive wastes from the nuclear power plants and to perform the research and development and other measures necessary for this work. SKB is the owner of CLAB, the Central Interim Storage Facility for spent fuel, located at Oskarshamn. CLAB was taken into operation in July 1985 and by the end of 1996 about 2500 tons of spent fuel have been received. At Forsmark the Final Repository for Radioactive Operational Waste (SFR) was taken into operation in April 1988. The repository is situated in crystalline rock under the Baltic Sea. SFR has currently a capacity of about 60000 m{sup 3} or waste. At the end of 1996 at total of 21000 m{sup 3} of waste has been deposited. Transportation from the reactor sites to CLAB and SFR is made by a specially designed ship, M/S Sigyn. The total cost for R,D and D during 1996 amounted to 124 MSEK (about 15 MUSD).

  9. Annual Report 1998

    Energy Technology Data Exchange (ETDEWEB)

    Chmielewska, D.; Infeld, E.; Preibisz, Z.; Zupranski, P. [eds.

    1999-10-01

    In the presented ``Annual Report 1998`` the scientific, organizational and educational activities of the Andrzej Soltan Institute for Nuclear Studies (SINS) are presented. The document is divided into two parts. First of them consists of the general information about management, scientific council, department of SINS, scientific staff, visiting scientists, list of research project (grants), PhD and DSc theses as well as the information about organized schools and exhibitions. The second one: ``Reports on Research`` describes the research activities of SINS. It is divided into 12 parts - in which the works of SINS departments and establishments are presented (Department of Nuclear Reactions, Department of Nuclear Spectroscopy and Technique, Department of Nuclear Electronics, Department of Radiation Shielding and Dosimetry, Department of Plasma Physics and Technology, Department of High Energy Physics, Department of Cosmic Radiation Physics, Department of Nuclear Theory, Department of Radiation Detectors, Department of Accelerator Physics and Technology, Department of Training an Consulting and Establishment for Nuclear Equipment). Each of these parts are preceded by a short overview given by the head of the given department. The foreword, in which the whole activities of the SINS are summarized, given by head of the Institute professor Z. Sujkowski is also given

  10. Annual Energy Review 2002

    Energy Technology Data Exchange (ETDEWEB)

    Seiferlein, Katherine E. [USDOE Energy Information Administration (EIA), Washington, DC (United States)

    2003-10-01

    The Annual Energy Review (AER) presents the Energy Information Administration’s historical energy statistics. For many series, statistics are given for every year from 1949 through 2002. The statistics, expressed in either physical units or British thermal units, cover all major energy activities, including consumption, production, trade, stocks, and prices, for all major energy commodities, including fossil fuels, electricity, and renewable energy sources. Publication of this report is required under Public Law 95–91 (Department of Energy Organization Act), Section 205(c), and is in keeping with responsibilities given to the Energy Information Administration (EIA) under Section 205(a)(2), which states: “The Administrator shall be responsible for carrying out a central, comprehensive, and unified energy data and information program which will collect, evaluate, assemble, analyze, and disseminate data and information....” The AER is intended for use by Members of Congress, Federal and State agencies, energy analysts, and the general public. EIA welcomes suggestions from readers regarding data series in the AER and in other EIA publications. Related Publication: Readers of the AER may also be interested in EIA’s Monthly Energy Review, which presents monthly updates of many of the data in the AER. Contact our National Energy Information Center for more information.

  11. Annual Energy Review 2000

    Energy Technology Data Exchange (ETDEWEB)

    Seiferlein, Katherine E. [USDOE Energy Information Administration (EIA), Washington, DC (United States)

    2001-08-01

    The Annual Energy Review (AER) presents the Energy Information Administration’s historical energy statistics. For many series, statistics are given for every year from 1949 through 2000. The statistics, expressed in either physical units or British thermal units, cover all major energy activities, including consumption, production, trade, stocks, and prices, for all major energy commodities, including fossil fuels, electricity, and renewable energy sources. Publication of this report is required under Public Law 95–91 (Department of Energy Organization Act), Section 205(c), and is in keeping with responsibilities given to the Energy Information Administration under Section 205(a)(2), which states: “The Administrator shall be responsible for carrying out a central, comprehensive, and unified energy data and information program which will collect, evaluate, assemble, analyze, and disseminate data and information....” The AER is intended for use by Members of Congress, Federal and State agencies, energy analysts, and the general public. EIA welcomes suggestions from readers regarding data series in the AER and in other EIA publications.

  12. Annual report 1997

    Energy Technology Data Exchange (ETDEWEB)

    Chmielewska, D.; Infeld, E.; Zupranski, P. [eds.

    1998-12-31

    In the presented ``Annual Report 1997`` the scientific, organizational end educational activities of the Andrzej Soltan Institute for Nuclear Studies (SINS) are presented. The document is divided into two parts. First of them consist of the general information about management, scientific council, department of SINS, scientific staff, visiting scientists, list of research project (grants), PhD and DSc theses as well as the information about organized schools and exhibitions. The second one: ``Reports on Research`` describes the research activities of SINS. It is divided into 12 parts - in which the works of SINS departments and establishments are presented (Department of Nuclear Reactions, Department of Nuclear Spectroscopy and Technique, Department of Nuclear Electronics, Department of Radiation Shielding and Dosimetry, Department of Plasma Physics and Technology, Department of High Energy Physics, Department of Cosmic Radiation Physics, Department of Atomic Nucleus Theory, Department of Radiation Detectors, Department of Accelerator Physics and Technology, Department of Training an Consulting and Establishment for Nuclear Equipment). Each of these parts are foreworded by short overview given by the head of appropriate department. The foreword, in which the whole activities of the SINS are summarized, given by head of the Institute professor Z. Sujkowski is also given

  13. ANNUAL INTERVIEWS (MAPS)

    CERN Multimedia

    Human Resources Division

    2002-01-01

    The calendar for the 2002/2003 annual interview programme is confirmed as normally from 15 November 2002 to 15 February 2002 as foreseen in Administrative Circular N° 26 (rev. 2). However, where it is preferred to be as close as possible to 12 months since the last interview, supervisors and staff concerned may agree to the interview taking place up to 15 March 2003. This may also be necessary due to the roles of different supervisors resulting from the particular situations of divisional re-restructurings and detachments this year. The report form template is as last year available on the HR Division Website. A banner on the internal homepage leads directly to the page with the form. In collaboration with AS Division, the MAPS form including the personal data for the first page can be generated via the Human Resources Toolkit (HRT) application. For this exercise each staff member can now generate his/her own MAPS form. Information about how to do this is available here. Human Resources Division Tel. ...

  14. 2007 LDRD ANNUAL REPORT

    Energy Technology Data Exchange (ETDEWEB)

    French, T

    2008-12-16

    I am pleased to present the fiscal year 2007 Laboratory Directed Research and Development (LDRD) annual report. This represents the first year that SRNL has been eligible for LDRD participation and our results to date demonstrate we are off to an excellent start. SRNL became a National Laboratory in 2004, and was designated the 'Corporate Laboratory' for the DOE Office of Environmental Management (EM) in 2006. As you will see, we have made great progress since these designations. The LDRD program is one of the tools SRNL is using to enable achievement of our strategic goals for the DOE. The LDRD program allows the laboratory to blend a strong basic science component into our applied technical portfolio. This blending of science with applied technology provides opportunities for our scientists to strengthen our capabilities and delivery. The LDRD program is vital to help SRNL attract and retain leading scientists and engineers who will help build SRNL's future and achieve DOE mission objectives. This program has stimulated our research staff creativity, while realizing benefits from their participation. This investment will yield long term dividends to the DOE in its Environmental Management, Energy, and National Security missions.

  15. Annual conference SAEE 2008

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    Technical and economic challenges of a 1 t CO{sub 2} society was the topic addressed by the 2008 annual conference of the Swiss Association for Energy Economics. One tonne of carbon dioxide per head and year as a long-term energy strategy is the theme of a presentation made by professor Konstantin Boulouchos from the Swiss Federal Institute of Technology ETH in Zurich, Switzerland. Professor Dr. Rainhard Madlener from the Institute for Future Energy Consumer Needs and Behaviour in Aachen, Germany, took a look at the one-ton CO{sub 2} vision as a focus for technical development. Professor Thomas F. Rutherford from the ETH presented an economic analysis of one-ton CO{sub 2} scenarios. Eduard Schumacher, former Chairman of the Board at the IWB utility in Basel, Switzerland, presented examples of how energy policy can be implemented, using the IWB's activities as an example. Hansruedi Kunz, Head of the Energy Department in the Building Department of the Canton of Zurich discussed the chances offered and the problems posed by the implementation of measures that are to lead to the meeting of energy visions for the year 2050. A podium and discussion session completed the conference

  16. Annual Energy Review 1997

    Energy Technology Data Exchange (ETDEWEB)

    Seiferlein, Katherine E. [USDOE Energy Information Administration (EIA), Washington, DC (United States)

    1998-07-01

    The Annual Energy Review (AER) presents the Energy Information Administration’s historical energy statistics. For many series, statistics are given for every year from 1949 through 1997. The statistics, expressed in either physical units or British thermal units, cover all major energy activities, including consumption, production, trade, stocks, and prices, for all major energy commodities, including fossil fuels, electricity, and renewable energy sources. Publication of this report is in keeping with responsibilities given to the Energy Information Administration (EIA) in Public Law 95–91 (Department of Energy Organization Act), which states, in part, in Section 205(a)(2) that: “The Administrator shall be responsible for carrying out a central, comprehensive, and unified energy data and information program which will collect, evaluate, assemble, analyze, and disseminate data and information....” The AER is intended for use by Members of Congress, Federal and State agencies, energy analysts, and the general public. EIA welcomes suggestions from readers regarding data series in the AER and in other EIA publications.

  17. Annual Site Environmental Report

    Energy Technology Data Exchange (ETDEWEB)

    Finley, Virginia [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

    2014-10-02

    This report provides the U.S. Department of Energy (DOE) and the public with information on the level of radioactive and non-radioactive pollutants (if any) that are added to the environment as a result of Princeton Plasma Physics Laboratory’s (PPPL) operations. The results of the 2013 environmental surveillance and monitoring program for PPPL’s are presented and discussed. The report also summarizes environmental initiatives, assessments, and community involvement programs that were undertaken in 2013.

  18. SERC 2011 Annual Report

    Science.gov (United States)

    2011-01-01

    techniques and approaches tailored to the defense environment. To meet the issues leading from our early experience, and extend the capabilities of...McGrath (ANSER), Mr. Walker Royce ( IBM ) • MBSE continues to evolve and mature; NDIA and INCOSE major players • Model-based Concept Engineering is a key...architecture that would provide stakeholders a mechanism to evaluate system of systems. This project is a rapid- turnaround (10 week) study motivated

  19. MEaSUREs Greenland Annual Ice Sheet Velocity Mosaics from SAR and Landsat, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set, part of the NASA Making Earth System Data Records for Use in Research Environments (MEaSUREs) program, contains annual ice velocity mosaics for the...

  20. MEaSUREs Annual Antarctic Ice Velocity Maps 2005-2017, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set, part of the NASA Making Earth System Data Records for Use in Research Environments (MEaSUREs) program, provides 12 annual maps of Antarctic ice...

  1. MEaSUREs Annual Antarctic Ice Velocity Maps 2005-2016, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set, part of the NASA Making Earth System Data Records for Use in Research Environments (MEaSUREs) program, provides 11 annual maps of Antarctic ice...

  2. Annual Site Environmental Report, 2004

    Energy Technology Data Exchange (ETDEWEB)

    Nuckolls, H.; /SLAC

    2006-04-19

    This report provides information about environmental programs during 2004 at the Stanford Linear Accelerator Center (SLAC). Seasonal activities that span calendar years are also included. Production of an annual site environmental report (ASER) is a requirement established by the United States Department of Energy (DOE) for all management and operating (M&O) contractors throughout the DOE complex. SLAC is a federally-funded, research and development center with Stanford University as the M&O contractor. The most noteworthy information in this report is summarized in this section. This summary demonstrates the effective application of SLAC environmental management in meeting the site's integrated safety management system (ISMS) goals. For normal daily activities, all SLAC managers and supervisors are responsible for ensuring that proper procedures are followed so that worker safety and health are protected; the environment is protected; and compliance is ensured. Throughout 2004, SLAC focused on these activities through the SLAC management systems (described in Chapter 3). These systems were also the way SLAC approached implementing ''greening of the government'' initiatives such as Executive Order 13148. The management systems at SLAC are effective, supporting compliance with all relevant statutory and regulatory requirements. There were no reportable releases to the environment from SLAC operations during 2004. In addition, many improvements were continued during 2004, in waste minimization, recycling, decreasing air emission rates, stormwater drain system, groundwater restoration, and planning for a chemical management system to manage chemical use better. Program-specific details discussed are: (1) Air Quality--SLAC operates its air quality management program in compliance with its established permit conditions: 2004 was the seventh consecutive year the air quality management program operated without receiving any notices of violation

  3. Pipeline dreams: people, environment, and the Arctic energy frontier

    National Research Council Canada - National Science Library

    Nuttall, Mark

    2010-01-01

    "With a focus on the North American Arctic and sub-Arctic, this book discusses how dreams of extracting resource wealth have been significant in influencing and shaping relations between indigenous...

  4. 2005 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    Chrzanowski, P; Walter, K

    2006-03-31

    As the cover of our ''2005 Annual Report'' highlights, Lawrence Livermore National Laboratory joined the international science community in celebrating the World Year of Physics in 2005, with special events and science outreach and education programs. Einstein's remarkable discoveries in 1905 provided an opportunity to reflect on how physics has changed the world during the last century and on the promise of future beneficial discoveries. For half of the past century, Lawrence Livermore, which was established to meet an urgent national security need, has been contributing to the advancement of science and technology in a very special way. Co-founder Ernest O. Lawrence was the leading proponent in his generation of large-scale, multidisciplinary science and technology teams. That's Livermore's distinctive heritage and our continuing approach as a national laboratory managed and operated by the University of California for the Department of Energy's National Nuclear Security Administration (DOE/NNSA). We focus on important problems that affect our nation's security and seek breakthrough advances in science and technology to achieve mission goals. An event in 2005 exemplifies our focus on science and technology advances in support of mission goals. In October, distinguished visitors came to Livermore to celebrate the tenth anniversary of the Accelerated Strategic Computing Initiative (now called the Advanced Simulation and Computing Program, or ASC). ASC was launched in 1995 by DOE/NNSA to achieve a million-fold increase in computing power in a decade. The goal was motivated by the need to simulate the three-dimensional performance of a nuclear weapon in sufficient resolution and with the appropriately detailed physics models included. This mission-driven goal is a key part of fulfilling Livermore's foremost responsibility to ensure that the nuclear weapons in the nation's smaller 21st-century stockpile remain

  5. Annual Report, 1998

    Energy Technology Data Exchange (ETDEWEB)

    Buettner, Herma G.; Leadbetter, Alan J. [eds.] [Institut Max von Laue - Paul Langevin (ILL), 38 - Grenoble (France)

    1999-11-01

    In this Annual Report a selection of about 30 scientific achievements are highlighted. These are intended to represent the huge range of high quality research carried out at ILL. In 1998 about 750 experiments were performed in the 225 days of reactor operation. The fields of magnetism and strongly correlated electron systems continue to be fertile and to throw up strong new growth. Remarkable new advances are coming from the applications of both existing and new neutron techniques and the development of new materials. These highlights concern superconductors, nano-magnetic particles, colossal magneto-resistance, magnetic-nuclear correlations, quantum spin systems and more. Novel magnetic measurements are also reported for a quasicrystal and on thin films of both normal and superconducting materials. Thanks to special abilities of neutrons to penetrate matter new results were obtained: following the production of novel intermetallic compounds, pressure dependence of phonon frequencies, the structure of glasses, solutions (in both bulk and thin films) and adsorbed phases; dynamics and relaxation in liquids; the confirmation of reptant motion in linear polymers, self-assembly and shear phenomena in liquid crystals. Three important results from nuclear physics are also included. These involve: fission-produced neutron-rich nuclei, weighing gamma photons in connection with the determination of fundamental constants and the determination of interatomic potentials from the slowing down process of atoms recoiling from gamma-ray emission - a direct link between nuclear and solid-state physics. The neutron experiments of importance for particle physics and biology will be reported next year

  6. 1998 annual review

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-05-01

    The Canadian Petroleum Products Institute (CPPI) is an association of Canadian companies involved in the refining, distribution and marketing of petroleum products. CPPI`s responsibilities include (1) establishing environmental policies, (2) establishing working relationships with governments to develop public policy, (3) developing guidelines for the safe handling of petroleum products, and (4) providing information about the petroleum industry to the public. This annual review summarizes industry operations and trends within the crude oil and petroleum products industry. In 1998, Canada`s 19 CPPI member refineries processed an average of 1.6 million barrels of crude oil per day. The CPPI developed a policy position on climate change and continued its strong support of the Canadian Voluntary Challenge and Registry Program. It initiated a major consumer information campaign regarding gasoline prices. It held a pollution prevention workshop to discuss issues related to air, land and water quality. It launched a website (www.cppi.ca) as another mechanism to provide its audience with information about the industry. Across Canada, CPPI`s regional offices supported a number of industry initiatives, such as the work in Dartmouth, NS, on a Risk-based Correction Action process for the clean-up of sites contaminated with petroleum products, discussions on the development of a used oil program for Quebec, regulatory reform in Ontario, and support by the Calgary office in the implementation of used oil recycling programs in the Prairies. CPPI also participated in discussions concerning the establishment of standards regarding sulphur and benzene in gasoline, and the future regarding the octane enhancing fuel additive MMT for transportation fuels. It was also reported that CPPI members are on track towards achieving a 65 per cent reduction in refinery benzene emissions between 1993 and 2000. tabs., figs.

  7. Competitive success of southern populations of Betula pendula and Sorbus aucuparia under simulated southern climate experiment in the subarctic.

    Science.gov (United States)

    Taulavuori, Kari; Taulavuori, Erja; Saravesi, Karita; Jylänki, Tanja; Kainulainen, Aila; Pajala, Jonna; Markkola, Annamari; Suominen, Otso; Saikkonen, Kari

    2017-06-01

    Global warming has been commonly accepted to facilitate species' range shifts across latitudes. Cross-latitudinal transplantations support this; many tree species can well adapt to new geographical areas. However, these studies fail to capture species' adaptations to new light environment because the experiments were not designed to explicitly separate species' responses to light and temperature. Here we tested reaction norms of tree seedlings in reciprocal transplantations 1,000 km apart from each other at two latitudes (60°N and 69°N). In contrast to past studies, we exposed our experimental plants to same temperature in both sites (temperature of 60°N growing site is recorded to adjust temperature of 69°N site in real time via Internet connection) while light environment (photoperiod, light quality) remained ambient. Shoot elongation and autumn coloration were studied in seedlings of two deciduous trees (Betula pendula and Sorbus aucuparia), which were expected to respond differently to day length. Sorbus as a member of Rosaceae family was assumed to be indifferent to photoperiod, while Betula responds strongly to day length. We hypothesized that (1) southern and northern populations of both species perform differently; (2) southern populations perform better in both sites; (3) autumn phenology of southern populations may delay in the northern site; (4) and Sorbus aucuparia is less dependent on light environment. According to the hypotheses, shoot elongation of northern population was inherently low in both species. An evolutionary consequence of this may be a competitive success of southern populations under warming climate. Southern population of B. pendula was delayed in autumn coloration, but not in growth cessation. Sorbus aucuparia was less responsive to light environment. The results suggest that light provides selection pressure in range shifts, but the response is species dependent.

  8. Encapsulated Environment

    NARCIS (Netherlands)

    McLellan, T.M.; Daanen, H.A.M.; Cheung, S.S.

    2013-01-01

    In many occupational settings, clothing must be worn to protect individuals from hazards in their work environment. However, personal protective clothing (PPC) restricts heat exchange with the environment due to high thermal resistance and low water vapor permeability. As a consequence, individuals

  9. Encapsulated environment

    NARCIS (Netherlands)

    McLellan, Tom M.; Daanen, Hein A M; Cheung, Stephen S.

    2013-01-01

    In many occupational settings, clothing must be worn to protect individuals from hazards in their work environment. However, personal protective clothing (PPC) restricts heat exchange with the environment due to high thermal resistance and low water vapor permeability. As a consequence, individuals

  10. Impact of Euro-Canadian agrarian practices: in search of sustainable import-substitution strategies to enhance food security in subarctic Ontario, Canada.

    Science.gov (United States)

    Spiegelaar, Nicole F; Tsuji, Leonard J S

    2013-01-01

    In Canada, food insecurity exists among Aboriginal (Inuit, Metis and First Nations) people living in remote northern communities, in part, because of their reliance on the industrialized, import-based food system. Local food production as a substitute to imports would be an adaptive response, but enhancement of food security via food localization requires reflection on previous failings of conventional agricultural strategies so that informed decisions can be made. In light of potential reintroduction of local food production in remote First Nations communities, we investigated the cultural, social and ecological effects of a 20th century, Euro-Canadian agrarian settlement on the food system of a subarctic First Nation; this will act as the first step in developing a more sustainable local food program and enhancing food security in this community. To investigate the socio-cultural impacts of the Euro-Canadian agrarian initiative on the food system of Fort Albany First Nation, purposive, semi-directive interviews were conducted with elders and other knowledgeable community members. Interview data were placed into themes using inductive analyses. To determine the biophysical impact of the agrarian initiative, soil samples were taken from one site within the cultivated area and from one site in an undisturbed forest area. Soil properties associated with agricultural use and productivity were assessed. To compare the means of a given soil property between the sites, one-tailed t-tests were employed. Vegetative analysis was conducted in both sites to assess disturbance. According to the interviewees, prior to the agrarian initiative, First Nation families harvested wild game and fish, and gathered berries as well as other forms of vegetation for sustenance. With the introduction of the residential school and agrarian initiative, traditional food practices were deemed inadequate, families were forced to work and live in the settlement (becoming less reliant on

  11. Nursing Facility Initiative Annual Report

    Data.gov (United States)

    U.S. Department of Health & Human Services — This annual report summarizes impacts from the Initiative to Reduce Avoidable Hospitalizations among Nursing Facility Residents in 2014. This initiative is designed...

  12. Florida annual general canvass statistics

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains annual quantities and value for all seafood products that are landed and sold by established seafood dealers and brokers in Florida. These...

  13. Summertime measurements of selected nonmethane hydrocarbons in the Arctic and sub-Arctic during the 1988 Arctic Boundary Layer Expedition (ABLE 3A)

    Science.gov (United States)

    Blake, Donald R.; Hurst, Dale F.; Smith, Tyrrel W.; Whipple, Wayne J.; Chen, Tai-Yih; Blake, Nicola J.; Rowland, F. Sherwood

    1992-10-01

    Approximately 1000 whole air samples were collected and assayed for selected C2-C5 hydrocarbons during the 6-week Arctic Boundary Layer Expedition (ABLE 3A). Transit flights enabled latitudinal (40°N to 83°N) and longitudinal (70°W to 155°W) profiles to be obtained for altitudes between 4000 and 6000 m yielding summertime background mixing ratios for ethane, ethyne, propane and n-butane of 1050±200, 100±40, 120±80 and 10±8 pptv, respectively. Drilling associated with oil exploration in the Alaskan North Slope area is suggested to be a probable source of the enhanced levels of alkanes observed in the Arctic region within a radius in excess of 300 km from Prudhoe Bay, Alaska. A significant number of pollution plumes were encountered which could be attributed to wildfires. Factors describing the emissions caused by biomass burning relative to ethane for ethyne (0.40) and propane (0.08) were determined. An increase of hydrocarbon mixing ratios with altitude was observed during all but two of the missions. Therefore, the Arctic and sub-Arctic are significantly influenced by the long-range transport of pollutants from nonlocal sources. A single vertical profile made in the vicinity of Wallops Island, Virginia, revealed elevated levels of isoprene, numerous hydrocarbons of the types associated with the leakage of natural gas and fossil fuel combustion, and substantial concentrations of nitrogen oxides and ozone. This implies that long-range transport of various gases from urban areas, combined with local biogenic emissions of isoprene, are significant sources of regional tropospheric ozone.

  14. Foliar pH as a new plant trait: can it explain variation in foliar chemistry and carbon cycling processes among subarctic plant species and types?

    Science.gov (United States)

    Cornelissen, J H C; Quested, H M; van Logtestijn, R S P; Pérez-Harguindeguy, N; Gwynn-Jones, D; Díaz, S; Callaghan, T V; Press, M C; Aerts, R

    2006-03-01

    Plant traits have become popular as predictors of interspecific variation in important ecosystem properties and processes. Here we introduce foliar pH as a possible new plant trait, and tested whether (1) green leaf pH or leaf litter pH correlates with biochemical and structural foliar traits that are linked to biogeochemical cycling; (2) there is consistent variation in green leaf pH or leaf litter pH among plant types as defined by nutrient uptake mode and higher taxonomy; (3) green leaf pH can predict a significant proportion of variation in leaf digestibility among plant species and types; (4) leaf litter pH can predict a significant proportion of variation in leaf litter decomposability among plant species and types. We found some evidence in support of all four hypotheses for a wide range of species in a subarctic flora, although cryptogams (fern allies and a moss) tended to weaken the patterns by showing relatively poor leaf digestibility or litter decomposability at a given pH. Among seed plant species, green leaf pH itself explained only up to a third of the interspecific variation in leaf digestibility and leaf litter up to a quarter of the interspecific variation in leaf litter decomposability. However, foliar pH substantially improved the power of foliar lignin and/or cellulose concentrations as predictors of these processes when added to regression models as a second variable. When species were aggregated into plant types as defined by higher taxonomy and nutrient uptake mode, green-specific leaf area was a more powerful predictor of digestibility or decomposability than any of the biochemical traits including pH. The usefulness of foliar pH as a new predictive trait, whether or not in combination with other traits, remains to be tested across more plant species, types and biomes, and also in relation to other plant or ecosystem traits and processes.

  15. Twenty-two years of warming, fertilisation and shading of subarctic heath shrubs promote secondary growth and plasticity but not primary growth.

    Directory of Open Access Journals (Sweden)

    Matteo Campioli

    Full Text Available Most manipulation experiments simulating global change in tundra were short-term or did not measure plant growth directly. Here, we assessed the growth of three shrubs (Cassiope tetragona, Empetrum hermaphroditum and Betula nana at a subarctic heath in Abisko (Northern Sweden after 22 years of warming (passive greenhouses, fertilisation (nutrients addition and shading (hessian fabric, and compare this to observations from the first decade of treatment. We assessed the growth rate of current-year leaves and apical stem (primary growth and cambial growth (secondary growth, and integrated growth rates with morphological measurements and species coverage. Primary- and total growth of Cassiope and Empetrum were unaffected by manipulations, whereas growth was substantially reduced under fertilisation and shading (but not warming for Betula. Overall, shrub height and length tended to increase under fertilisation and warming, whereas branching increased mostly in shaded Cassiope. Morphological changes were coupled to increased secondary growth under fertilisation. The species coverage showed a remarkable increase in graminoids in fertilised plots. Shrub response to fertilisation was positive in the short-term but changed over time, likely because of an increased competition with graminoids. More erected postures and large, canopies (requiring enhanced secondary growth for stem reinforcement likely compensated for the increased light competition in Empetrum and Cassiope but did not avoid growth reduction in the shade intolerant Betula. The impact of warming and shading on shrub growth was more conservative. The lack of growth enhancement under warming suggests the absence of long-term acclimation for processes limiting biomass production. The lack of negative effects of shading on Cassiope was linked to morphological changes increasing the photosynthetic surface. Overall, tundra shrubs showed developmental plasticity over the longer term. However, such

  16. Combined effects of environmental disturbance and climate warming on insect herbivory in mountain birch in subarctic forests: Results of 26-year monitoring.

    Science.gov (United States)

    Kozlov, M V; Zverev, V; Zvereva, E L

    2017-12-01

    Both pollution and climate affect insect-plant interactions, but the combined effects of these two abiotic drivers of global change on insect herbivory remain almost unexplored. From 1991 to 2016, we monitored the population densities of 25 species or species groups of insects feeding on mountain birch (Betula pubescens ssp. czerepanovii) in 29 sites and recorded leaf damage by insects in 21 sites in subarctic forests around the nickel-copper smelter at Monchegorsk, north-western Russia. The leaf-eating insects demonstrated variable, and sometimes opposite, responses to pollution-induced forest disturbance and to climate variations. Consequently, we did not discover any general trend in herbivory along the disturbance gradient. Densities of eight species/species groups correlated with environmental disturbance, but these correlations weakened from 1991 to 2016, presumably due to the fivefold decrease in emissions of sulphur dioxide and heavy metals from the smelter. The densities of externally feeding defoliators decreased from 1991 to 2016 and the densities of leafminers increased, while the leaf roller densities remained unchanged. Consequently, no overall temporal trend in the abundance of birch-feeding insects emerged despite a 2-3°C elevation in spring temperatures. Damage to birch leaves by insects decreased during the observation period in heavily disturbed forests, did not change in moderately disturbed forests and tended to increase in pristine forests. The temporal stability of insect-plant interactions, quantified by the inverse of the coefficient of among-year variations of herbivore population densities and of birch foliar damage, showed a negative correlation with forest disturbance. We conclude that climate differently affects insect herbivory in heavily stressed versus pristine forests, and that herbivorous insects demonstrate diverse responses to environmental disturbance and climate variations. This diversity of responses, in combination with the

  17. Phenological diversity in the interactions between winter moth (Operophtera brumata) larvae and parasitoid wasps in sub-arctic mountain birch forest.

    Science.gov (United States)

    Vindstad, O P L; Hagen, S B; Jepsen, J U; Kapari, L; Schott, T; Ims, R A

    2011-12-01

    Population cycles of the winter moth (Operophtera brumata) in sub-arctic coastal birch forests show high spatiotemporal variation in amplitude. Peak larval densities range from levels causing little foliage damage to outbreaks causing spatially extensive defoliation. Moreover, outbreaks typically occur at or near the altitudinal treeline. It has been hypothesized that spatiotemporal variation in O. brumata cycle amplitude results from climate-induced variation in the degree of phenological matching between trophic levels, possibly between moth larvae and parasitoids. The likelihood of mismatching phenologies between larvae and parasitoids is expected to depend on how specialized parasitoids are, both as individual species and as a guild, to attacking specific larval developmental stages (i.e. instars). To investigate the larval instar-specificity of parasitoids, we studied the timing of parasitoid attacks relative to larval phenology. We employed an observational study design, with sequential sampling over the larval period, along an altitudinal gradient harbouring a pronounced treeline outbreak of O. brumata. Within the larval parasitoid guild, containing seven species groups, the timing of attack by different groups followed a successional sequence throughout the moth's larval period and each group attacked 1-2 instars. Such phenological diversity within parasitoid guilds may lower the likelihood of climate-induced trophic mismatches between victim populations and many/all of their enemies. Parasitism rates declined with increasing altitude for most parasitoid groups and for the parasitoid guild as a whole. However, the observed spatiotemporal parasitism patterns provided no clear evidence for or against altitudinal mismatch between larval and parasitoid phenology.

  18. Annual report 99

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-07-01

    This volume of the Annual Report for the year 1999 provides the best illustration of this attempt: 30 highlights are presented covering a remarkable range of science and technique. As with last year's report, a wide spectrum of neutron science is embraced from biology, through to studies in chemistry, materials science and magnetism, to particle physics. To maintain this excellence, important efforts have been made in instrumentation; they are described in the technical section together with the Millennium Programme. This report is an appropriate illustration of the unique value of neutron methods for the study of a wide range of materials proving the usefulness of large-scale facilities such as the ILL. In 1999, the reactor operated for 208 days and more than 700 experiments were carried out in over 4400 days of scheduled beam time. Unfortunately, there was a failure of the hot source in December 1999 leading to a loss of about 20 days of beam time. Therefore, in 2000 the reactor will operate without the hot source. However, this will only affect 10 % of ILL's instruments. As in previous years, a large number of high-quality experiments was proposed and performed to tackle a broad range of scientific questions. For example in biology, the results presented here demonstrate that the contrast-variation method combined with small-angle scattering and neutron reflectivity techniques is a remarkable and unique tool for the investigation of biological materials. In the field of soft matter and liquids, it is known that confined geometry substantially modifies the properties of systems as diverse as simple water, polymers and quantum fluids. Neutron scattering experiments, presented here, have revealed the static and dynamic characteristics of these materials under conditions of confinement. In materials sciences, the penetration and contrast properties of neutrons are exploited, particularly in the case of small-angle scattering applied to alloys. Finally, the

  19. NERI 2004 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    None

    2004-01-01

    The United States Department of Energy (DOE) created the Nuclear Energy Research Initiative (NERI) in Fiscal Year (FY) 1999 in response to recommendations provided by the President's Committee of Advisors on Science and Technology. The purpose of NERI is to sponsor research and development (R&D) in the nuclear energy sciences to address the principal barriers to the future use of nuclear energy in the United States. NERI is helping to preserve the nuclear science and engineering infrastructure within the Nation's universities, laboratories, and industry, and is advancing the development of nuclear energy technology, enabling the United States to maintain a competitive position in nuclear science and technology. Research under this initiative also addresses issues associated with the maintenance of existing U.S. nuclear plants. The NERI program is managed and funded by DOE's Office of Nuclear Energy, Science and Technology. ''The Nuclear Energy Research Initiative 2004 Annual Report'' serves to inform interested parties of progress made in NERI on a programmatic level as well as research progress made on individual NERI projects. Section 2 of this report provides background on the creation and implementation of NERI and on the focus areas for NERI research. Section 3 provides a discussion on NERI's mission, goals and objectives, and work scope. Section 4 highlights the major accomplishments of the NERI projects and provides brief summaries of the NERI research efforts that were completed in 2004. Section 5 provides a discussion on the impact NERI has had on U.S. university nuclear programs. Sections 6 through 8 provide project status reports by research area for each of the fiscal year (FY) 2001 and 2002 projects that were active in FY 2004. Research objectives, progress made over the last year, and activities planned for the next year are described for each project. Sections 9 through 11 present each of the newly awarded 2005

  20. Long term effects of fire on carbon and nitrogen pools and fluxes in the arctic permafrost and subarctic forests (ARCTICFIRE)

    Science.gov (United States)

    Pumpanen, Jukka; Köster, Kajar; Aaltonen, Heidi; Köster, Egle; Zhou, Xuan; Zhang-Turpeinen, Huizhong; Heinonsalo, Jussi; Palviainen, Marjo; Sun, Hui; Biasi, Christina; Bruckman, Viktor; Prokushkin, Anatoly; Berninger, Frank

    2017-04-01

    Boreal forests, which are to a large extent located on permafrost soils, are a crucial part of the climate system because of their large soil carbon (C) pool. Even small change in this pool may change the terrestrial C sink in the arctic into a source with a consequent increase in CO2 concentrations. About 1% of boreal forests are exposed to fire annually, which affects the soil and permafrost under them. Thawing of permafrost increases the depth of the active layer containing large C and N stocks. In addition to temperature, the decomposition of soil organic matter depends on its chemical composition which may also be affected by fires. Part of the soil organic matter is turned into pyrogenic C and N resistant to decomposition. We studied the effect of forest fires on soil greenhouse gas fluxes (CO2, CH4 and N2O)and biogenic volatile organic compound fluxes using portable chambers. The amount of easily decomposable and recalcitrant fractions in soil organic matter were determined with water, ethanol and acid extraction, and the natural 13C and 15N abundances as well as chemical quality with Fourier Transform Infrared Spectroscopy (FTIR) were studied. Also, changes in microbial community structure and composition were analyzed with next generation pyrosequencing. Our preliminary results indicate that soil CO2 effluxes were significantly decreased immediately after the fire, and the recovery to pre-fire level took several decades. Soils were a small sink of CH4 and a source of N2O in all age classes, and the CH4 uptake was increased and N2O fluxes decreased still 20 years following the fire. A clear vertical distribution was observed in the amount of extractable soil organic matter the amount of extractable organic matter being highest in the soil surface layers and decreasing with depth. The natural 13C and 15N abundances and FTIR spectra and changes in microbial community composition are still under analysis.