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We investigated experimental warming and simulated grazing (clipping) effects on rangeland quality, as indicated by vegetation production and nutritive quality, in winter-grazed meadows and summer-grazed shrublands on the Tibetan Plateau, a rangeland system experiencing climatic and pastoral land use changes. Warming decreased total aboveground net primary productivity (ANPP) by 40 g.m?�.yr?� at the meadow habitats and decreased palatable ANPP (total ANPP minus non-palatable forb ANPP) by 10 g.m?�.yr?� at both habitats. The decreased production of the medicinal forb Gentiana straminea and the increased production of the non-palatable forb Stellera chamaejasme with warming also reduced rangeland quality. At the shrubland...
The global mean surface temperature increased 0.85°C during the period 1880 – 2012. Some climate models predict an additional warming of up 2 to 4 ◦ C over the next 100 years for the primary breeding grounds for North American ducks. Such an increase has been predicted to reduce mid - continent breeding duck populations by >70%. Managing continental duck populations in the face of climate change requires understanding how waterfowl have responded to historical spatio - temporal climatic variation. However, such responses to climate may be obscured by how ducks respond to variation in land cover. We estimated effects of climate on settlement patterns of breeding ducks in the Prairie - Parkland Region (PPR), boreal...
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Circumpolar Arctic Lake Cover data theme, used in the creation of the Circumpolar Arctic Vegetation Map. Lake cover strongly affects the albedo, or reflectance, of the land surface over large areas of the Arctic and is useful for delineating extensive wetlands. Lake cover was based on the number of AVHRR water pixels in each mapped polygon, divided by the total number of pixels in the polygon. Since the imagery has a pixel size of 1 km2, lake cover is underestimated for areas with many small lakes. No pixels were sampled within two pixels (2 km) of the coastline to avoid including ocean pixels. Integrated Landscape Units (ILUM) used to create the Circumpolar Arctic Vegetation Map (CAVM). The ILUM is the union...
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Circumpolar Arctic Region Floristic Provinces data theme, used in the creation of the Circumpolar Arctic Vegetation Map. Floristic sectors characterize the considerable east-west floristic variation within the subzones. The more northern Arctic bioclimate subzones have a relatively consistent core of Arctic plant species that occur around the circumpolar region. Further south, local east-west variation is related to a variety of factors, including different paleohistories and the greater climatic heterogeneity. Large north-south trending mountain ranges, primarily in Asia, have also restricted the exchange of species between parts of the Arctic. Yurtsev (1994) delineated six floristic provinces and 20 subprovinces...
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Conclusions: Caribou demonstrated patterns of avoidance near linear features such as pipelines, roads, and other oil field structures. Females demonstrated heightened avoidance, especially during calving seasons. Thresholds/Learnings: Synopsis: This study documented the behavioural reactions of caribou to oil development in the circumpolar regions of the northern hemisphere. Researchers observed patterns of avoidance near linear features such as pipelines, roads, and other oil field structures. Female caribou, especially those accompanied by calves avoided these areas in particular. Male caribou were more apt to occupy areas influenced by oil field structures and activity. In summary, the patterns oil field development...
Shrubs have increased in abundance and dominance in arctic and alpine regions in recent decades. This often dramatic change, likely due to climate warming, has the potential to alter both the structure and function of tundra ecosystems. The analysis of shrub growth is improving our understanding of tundra vegetation dynamics and environmental changes. However, dendrochronological methods developed for trees, need to be adapted for the morphology and growth eccentricity of shrubs. Here, we review current and developing methods to measure radial and axial growth, estimate age, and assess growth dynamics in relation to environmental variables. Recent advances in sampling methods, analysis and applications have improved...
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Data for the Alaska Arctic Tundra Vegetation Map (AATVM) was obtained from the Circumpolar Arctic Vegetation Map (CAVM). A 1:4 million-scale color-infrared (CIR) image of AVHRR satellite data was used as a base map. Data for each 1-km AVHRR pixel were selected at the time of maximum greenness from biweekly images from 11 July to 30 August 1993 and 1995. The minimum size on the map is 14 km diameter for polygon features and 8 km for linear features. The dominant vegetation type of each polygon was mapped with the recognition that polygons at this scale contain many vegetation types. Some of this heterogeneity can be characterized by topographic sequence.
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Circumpolar Arctic Vegetation data theme, used in the creation of the Circumpolar Arctic Vegetation Map. Additional information about this dataset is available at: http://www.arcticatlas.org/maps/themes/cp/cpsc Integrated Landscape Units (ILUM) used to create the Circumpolar Arctic Vegetation Map (CAVM). The ILUM is the union of all individual data themes used to create the CAVM. The Circumpolar Arctic Vegetation Map shows the types of vegetation that occur across the Arctic, between the ice-covered Arctic Ocean to the north and the northern limit of forests to the south. The CAVM team grouped over 400 described plant communities into 16 different physiognomic units based on plant growth forms. An international...
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This map shows the Alpine Dwarf Shrub Tundra conservation element data in the CYR study area. Layers include: Distribution map of the alpine dwarf shrub tundra CE; Current, near-term, and long-term status of alpine dwarf shrub tundra in the CYR study area. These data are provided by Bureau of Land Management (BLM) "as is" and may contain errors or omissions. The User assumes the entire risk associated with its use of these data and bears all responsibility in determining whether these data are fit for the User's intended use. These data may not have the accuracy, resolution, completeness, timeliness, or other characteristics appropriate for applications that potential users of the data may contemplate. The User...
Shrubs have increased in abundance and dominance in arctic and alpine regions in recent decades. This often dramatic change, likely due to climate warming, has the potential to alter both the structure and function of tundra ecosystems. The analysis of shrub growth is improving our understanding of tundra vegetation dynamics and environmental changes. However, dendrochronological methods developed for trees, need to be adapted for the morphology and growth eccentricity of shrubs. Here, we review current and developing methods to measure radial and axial growth, estimate age, and assess growth dynamics in relation to environmental variables. Recent advances in sampling methods, analysis and applications have improved...
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This map shows the Alpine and Arctic Tussock Tundra conservation element data in the CYR study area. Layers include: Distribution map of the alpine and Arctic tussock tundra CE; Summer Warmth Index for alpine dwarf shrub tundra and alpine and Arctic tussock tundra for the current condition and long-term future; Current, near-term, and long-term status of alpine and Arctic tussock tundra in the CYR study area. These data are provided by Bureau of Land Management (BLM) "as is" and may contain errors or omissions. The User assumes the entire risk associated with its use of these data and bears all responsibility in determining whether these data are fit for the User's intended use. These data may not have the accuracy,...
To assess the North American high-latitude vegetation response to the rising temperature, we derived NDVI trend for 91.2% of the non-water, non-snow land area of Canada and Alaska using the peak-summer Landsat surface reflectance data of 1984–2012. Our analysis indicated that 29.4% and 2.9% of the land area of Canada and Alaska showed statistically significant positive (greening) and negative (browning) trends respectively, at significance level p < 0.01, after burned forest areas were masked out. The area with greening trend dominated over that with browning trend for all land cover types. The greening occurred primarily in the tundra of western Alaska, along the north coast of Canada and in northeastern Canada;...
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Permafrost extent of Russia, from the Land Resources of Russia collection. Full description of this and accompanying datasets can be found at http://www.iiasa.ac.at/Research/FOR/russia_cd/perm.htm .
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The Circumpolar Arctic Vegetation Map (CAVM) shows the types of vegetation that occur across the Arctic, between the ice-covered Arctic Ocean to the north and the northern limit of forests to the south. The CAVM team grouped over 400 described plant communities into 16 different physiognomic units based on plant growth forms. An international team of arctic vegetation scientists representing the six countries of the Arctic (Canada, Greenland, Iceland, Norway, Russia, and the United States) prepared the map. Detailed descriptions of the methods used to create the map can be found at: http://www.geobotany.uaf.edu/cavm/
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Circumpolar Arctic Bioclimate Subzones data theme, used in the creation of the Circumpolar Arctic Vegetation Map. Additional information about this dataset is available at: http://www.arcticatlas.org/maps/themes/cp/cpbz Integrated Landscape Units (ILUM) used to create the Circumpolar Arctic Vegetation Map (CAVM). The ILUM is the union of all individual data themes used to create the CAVM. The Circumpolar Arctic Vegetation Map shows the types of vegetation that occur across the Arctic, between the ice-covered Arctic Ocean to the north and the northern limit of forests to the south. The CAVM team grouped over 400 described plant communities into 16 different physiognomic units based on plant growth forms. An...
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Circumpolar Arctic Landscape theme, used in the creation of the Circumpolar Arctic Vegetation Map (CAVM). The landscape map displays regions of plains, hills, mountains, glaciers and lakes. Generally, plains are flat or gently rolling landscapes less than 200 m above sea level. Hills are more dissected than plains (more surface roughness) and are 200-500 m in elevation. Mountains have greater surface roughness and are above 500 m in elevation. Integrated Landscape Units (ILUM) used to create the Circumpolar Arctic Vegetation Map (CAVM). The ILUM is the union of all individual data themes used to create the CAVM. The Circumpolar Arctic Vegetation Map shows the types of vegetation that occur across the Arctic, between...
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Changes in Arctic coastal ecosystems in response to global warming may be some of the most severe on the planet. A better understanding and analysis of the rates at which these changes are expected to occur over the coming decades is crucial in order to delineate high-priority areas that are likely to be affected by climate changes. The data provided in this release are part of a study that assessed the likelihood of changes to a barrier island – lagoon systems in response to projected changes in atmospheric and oceanographic forcing associated with Arctic warming. Arey Lagoon and the surrounding area near Barter Island, Alaska, were focused upon as part of this pilot study. The study investigates the dominance...
To assess the North American high-latitude vegetation response to the rising temperature, we derived NDVI trend for 91.2% of the non-water, non-snow land area of Canada and Alaska using the peak-summer Landsat surface reflectance data of 1984–2012. Our analysis indicated that 29.4% and 2.9% of the land area of Canada and Alaska showed statistically significant positive (greening) and negative (browning) trends respectively, at significance level p < 0.01, after burned forest areas were masked out. The area with greening trend dominated over that with browning trend for all land cover types. The greening occurred primarily in the tundra of western Alaska, along the north coast of Canada and in northeastern Canada;...
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Circumpolar Arctic Vegetation data theme, used in the creation of the Circumpolar Arctic Vegetation Map. Integrated Landscape Units (ILUM) used to create the Circumpolar Arctic Vegetation Map (CAVM). The ILUM is the union of all individual data themes used to create the CAVM. The Circumpolar Arctic Vegetation Map shows the types of vegetation that occur across the Arctic, between the ice-covered Arctic Ocean to the north and the northern limit of forests to the south. The CAVM team grouped over 400 described plant communities into 16 different physiognomic units based on plant growth forms. An international team of arctic vegetation scientists representing the six countries of the Arctic (Canada, Greenland, Iceland,...
map background search result map search result map Caribou in the Changing North Circumpolar Arctic Bioclimate Subzones Circumpolar Arctic Substrate Chemistry Land resources of Russia - Permafrost extent (percent area) Circumpolar Arctic Lake Cover (% water coverage) Circumpolar Arctic Landscape Circumpolar Arctic Region Floristic Provinces Circumpolar Arctic Vegetation Alaska Arctic Vegetation Circumpolar Arctic Vegetation Surficial geology of the Dalton Highway (Itkillik-Sagavanirktok rivers) area, southern Arctic foothills, Alaska Modeled 21st century storm surge, waves, and coastal flood hazards and supporting oceanographic and geological field data (2010 and 2011) for Arey and Barter Islands, Alaska and vicinity BLM REA CYR 2013 Alpine and Arctic Tussock Tundra BLM REA CYR 2013 Alpine Dwarf Shrub Tundra Modeled 21st century storm surge, waves, and coastal flood hazards and supporting oceanographic and geological field data (2010 and 2011) for Arey and Barter Islands, Alaska and vicinity Surficial geology of the Dalton Highway (Itkillik-Sagavanirktok rivers) area, southern Arctic foothills, Alaska Alaska Arctic Vegetation BLM REA CYR 2013 Alpine and Arctic Tussock Tundra BLM REA CYR 2013 Alpine Dwarf Shrub Tundra Circumpolar Arctic Bioclimate Subzones Circumpolar Arctic Substrate Chemistry Circumpolar Arctic Lake Cover (% water coverage) Circumpolar Arctic Landscape Circumpolar Arctic Region Floristic Provinces Circumpolar Arctic Vegetation Circumpolar Arctic Vegetation Caribou in the Changing North Land resources of Russia - Permafrost extent (percent area)