The impacts of permafrost thaw slump events on limnological variables in upland tundra lakes, Mackenzie Delta region

2016 ◽  
Vol 189 (1) ◽  
pp. 11-35 ◽  
Author(s):  
Adam J. Houben ◽  
Todd D. French ◽  
Steven V. Kokelj ◽  
Xiaowa Wang ◽  
John P. Smol ◽  
...  
Keyword(s):  
Mackenzie Delta ◽  
Delta Region ◽  
Permafrost Thaw

From pre-freshet to pre-freeze: a field survey of the fate of organic matter remobilized from the thawing permafrost to the coastal waters of the Mackenzie Delta region

2020 ◽  
Author(s):  
Martine Lizotte ◽  
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Coastal Waters ◽  
Drainage Basin ◽  
Numerical Models ◽  
Biogeochemical Cycling ◽  
The Arctic ◽  
Mackenzie Delta ◽  
Delta Region ◽  
Temporal Sampling

<p>Thawing of permafrost in the Mackenzie Delta region of northern Canada, coupled with an increase in river discharge, prompts the release of particulate and dissolved organic matter from the largest Arctic drainage basin in North America into the Arctic Ocean. While this ongoing process is well-recognized and its rate is accelerating, the fate of the newly-mobilized organic matter as it transits from the watershed through the delta and into the marine system remains poorly understood. In the framework of the H2020 Nunataryuk project, and in partnership with ArcticNet and Sentinel North, we conducted intensive field expeditions in the Mackenzie Delta from April to September 2019. The temporal sampling scheme of this project allowed the investigation of ambient conditions in the coastal waters under a full ice cover prior to the spring freshet, during the ice break-up, in summer, as well as in fall prior to the freeze-up period. In order to capture the fluvial-marine transition zone and with specific challenges related to shallow waters and changing seasons, the field sampling was conducted using several platforms: helicopters, snowmobiles and small boats. Water column profiles of physical and optical variables were measured on site, and water and sediment samples were collected and preserved for the determination of the composition and sources of particulate and dissolved organic matter, as well as its biogeochemical cycling in the coastal environment. Beyond improving our understanding of the origin and fate of this re-mobilized organic matter, the data gathered will serve as a new basis for the ground truthing of remotely sensed images in a changing arctic environment. Finally, the tuned satellite data will be incorporated into numerical models, providing better predictions of the impacts of permafrost thaw on local biogeochemical cycling and ultimately on sea-air fluxes of carbon dioxide and global climate.</p>

Reindeer herding as private enterprise in Canada

Polar Record ◽  
1984 ◽  
Vol 22 (137) ◽  
pp. 127-136 ◽  
Author(s):  
J. K. Stager
Keyword(s):  
Northwest Territories ◽  
Private Enterprise ◽  
Private Ownership ◽  
Mackenzie Delta ◽  
Reindeer Herding ◽  
Delta Region ◽  
Management Decisions ◽  
Management Techniques ◽  
Government Management ◽  
Canadian Wildlife

AbstractAfter unsuccessful introductions of reindeer into Canada during the early decades of this century, a herd brought from Alaska in 1935 was maintained successfully under government management (latterly under the Canadian Wildlife Service) for almost 40 years in the Mackenzie Delta region, Northwest Territories. Sold in 1974 into private ownership, the herd has since increased substantially in size; new management techniques have been developed to herd, handle and slaughter the animals. Meat, antlers in velvet and skins are the main products of a small but profitable local industry under native ownership. Currently numbering some 16 000 animals, the herd now justifies new management decisions affecting its future size and the scope of the enterprise.

scholarly journals Vegetation of the Continental Northwest Territories at 6 ka BP

2007 ◽  
Vol 49 (1) ◽  
pp. 37-43 ◽  
Author(s):  
Glen M. MacDonald
Keyword(s):  
Northwest Territories ◽  
Populus Tremuloides ◽  
Picea Mariana ◽  
Picea Glauca ◽  
Pinus Banksiana ◽  
Arctic Tundra ◽  
Range Limits ◽  
Mackenzie Delta ◽  
Delta Region ◽  
Low Arctic

ABSTRACTPollen records are used to reconstruct vegetation in the continental Northwest Territories at 6 ka (6000 14C yr BP). Picea glauca, P mariana, Larix laricina, Populus tremuloides, P. balsamifera, Alnus crispa and A. incana were present throughout their modern ranges in the Boreal and Subarctic Forest Zones by 6000 BP. Pinus banksiana, however, had not yet reached its present northern limits. Population densities of the dominant trees, Picea glauca and Picea mariana, were close to, or as high as, present. In the Mackenzie Delta region the range limit of Picea glauca was approximately 25 km north of its modern location just prior to 6000 BP. In contrast, the northern limits of the forest in central Canada were similar to present. The tundra vegetation close to the edge of the forest was similar to modern Low Arctic Tundra. Development of extensive Sphagnum peatlands had begun in the forested areas and the adjacent Low Arctic Tundra. Palaeoecological information regarding vegetation at 6000 BP remains lacking for the northeastern half of the study area. Therefore, the nature of the vegetation in much of the area now occupied by Low Arctic and Middle Arctic Tundra remains unknown. Important vegetation changes that occurred following 6 ka include : (1) the advance of Pinus banksiana to its present northern range limits, (2) the retreat of the northern range limits of Picea glauca in the Mackenzie Delta region between 6000 and 3500 BP and (3) the rapid and marked increase in the population density of Picea mariana in the treeline zone of the central Northwest Territories at 5000 BP followed by a decline at 4000 BP.

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