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Bells Corners, Canada

White C.A.,Parks Canada Agency | Perrakis D.D.B.,British Columbia Ministry of Natural Resource Operations | Kafka V.G.,Parks Canada Agency | Ennis T.,Nature Conservancy of Canada
Fire Ecology | Year: 2011

Currently, high intensity, large-area lightning fires that burn during droughts dominate Canada's fire regimes. However, studies from several disciplines clearly show that humans historically ignited burns within this matrix of large fires. Two approaches for fire research and management have arisen from this pattern: a "large-fire biophysical paradigm" related to lightning-ignited fires, and an "eco-cultural paradigm" related to human-caused burning. Working at the edge between biophysically driven fires and eco-cultural burns, and their associated management and research paradigms, presents unique challenges to land managers. We proceed by describing fire frequency trends across Canada, and how an interaction between changing climatic and cultural factors may provide better causal explanations for observed patterns than either group of factors alone. We then describe four case histories of fire restoration into Canadian landscapes moving through evolution, or deliberate intent, towards increasing emphasis on an eco-cultural paradigm. We show that use of cultural burns maintains this facet of the long-term regime while providing greater capacity for larger, higher intensity fires to occur with fewer negative ecological and socio-economic implications. Key lessons learned by practitioners restoring fire to landscapes include: 1) fire is only one process in ecosystems that also include other complex interactions, and thus restoration of fire alone could have unintended consequences in some ecosystems; 2) recognizing long-term human roles of not only fire managers, but also hunters and gatherers is critical in restoration programs; and 3) this diversity of past, present, and future ecological and cultural interactions with fire can link managers to a broad constituency of stakeholders. Bringing this variety of people and interests into the decision-making processes is a necessary pre-requisite to successful fire management at the edge. Source

Wang M.,Northwest University, China | Wang M.,McGill University | Moore T.R.,McGill University | Talbot J.,University of Montreal | Riley J.L.,Nature Conservancy of Canada
Global Biogeochemical Cycles | Year: 2015

Northern peatlands have stored large amounts (∼500 Pg) of carbon (C) since the last glaciation. Combined with peat C are nutrients such as nitrogen (N), phosphorus (P), calcium (Ca), magnesium (Mg), and potassium (K), each of which plays an important role in plant production, litter decomposition, and the biogeochemical functioning of peatlands. Yet little attention has been given to the amounts of these nutrients stored in northern peatlands and their stoichiometry with C. Here we use data on nutrient concentrations in over 400 peat profiles in Ontario, Canada, representing bogs, fens, and swamps and their vegetation. We show that the C:N ratio is high (>40:1) in vegetation and litter but declines through the peat profiles to reach ratios between 22:1 and 29:1 in peat below 50 cm. In contrast, the C:P ratio rises from vegetation and litter (500:1 to 1300:1) to 1500:1 to 2000:1 in the lower part of the peat profile. Ratios of C to Ca, Mg, and K vary with peatland type. Most of these stoichiometric changes occur in the early stages of organic matter decomposition, where the litter structure remains intact. We estimate that ∼18 Pg of N has been stored in northern peatlands since deglaciation, reflecting high N accumulation rates (∼0.8 g m-2 yr-1), whereas P accumulation is small (∼0.3 Pg, ∼0.016 g m-2 yr-1), indicating that P is quickly recycled in the surface layers. ©2014. American Geophysical Union. All Rights Reserved. Source

Chu C.,Nature Conservancy of Canada | Chu C.,University of Toronto | Koops M.A.,Canadian Department of Fisheries and Oceans | Randall R.G.,Canadian Department of Fisheries and Oceans | And 2 more authors.
Freshwater Science | Year: 2014

The nearshore zones of the Great Lakes provide essential habitat for biota and are perhaps the region of the lakes most susceptible to human impacts. The objective of our study was to develop a fish habitat classification for the nearshore zone of Lake Ontario based on physical characteristics of that zone, land cover in the surrounding watershed, and fish community patterns. Nearly 80% of the spatial variation in fish community data was described by 2 physical variables (average fetch and bathymetric slope of the nearshore zone) and 2 land-cover variables (urban/industrial development and mixed forest cover) in adjacent watersheds. These variables are likely to be surrogates for other conditions in the nearshore, such as wave action, circulation, vegetation, and water quality. A 12-group fish habitat classification was developed from those variables. Validation and significance tests identified similarities and differences among the fish communities in the classes and indicated that the number of classes should be collapsed to 3: exposed, sheltered, and developed/urbanized. In general, the western basin of the lake was developed, the central region was exposed, and the eastern region of the lake was a mix of exposed and sheltered classes. These results highlight that even in lakes as large as Lake Ontario, the nearshore fish community is influenced by watershed land cover, and emphasize that management or restoration of the nearshore ecosystem in lakes will require integration of aquatic, watershed, and land-cover management. © 2014 by The Society for Freshwater Science. Source

Bleho B.I.,Golder Assoc. Inc. | Koper N.,University of Manitoba | Borkowsky C.L.,Critical Wildlife Habitat Program | Hamel C.D.,Nature Conservancy of Canada
American Midland Naturalist | Year: 2015

The western prairie fringed-orchid is a rare North American orchid restricted to a few remnants of wet to mesic tallgrass prairie. It is federally listed in both Canada and the United States and both countries have developed a recovery plan for the species. Two key management objectives are to monitor population trends and identify beneficial management practices. We used 21 y of data from the Manitoba metapopulation to assess effects of weather and land management on this species. Our results suggest the metapopulation in Manitoba is relatively stable. Western prairie fringed-orchids appear to benefit most from a combination of warm temperatures in the previous growing season followed by cool snowy but short winters and wet springs. Periodic burning (e.g., every 2-3 y) may benefit fringed-orchids, whereas grazing may be detrimental. This was not a controlled experiment, however, and gaps in the data may have influenced our results. Prescribed burning is a viable management tool for curtailing woody invasion and both burning and grazing reduce litter and grass cover, but careful consideration of timing, frequency, and intensity of application is required so management does not hinder fringed-orchid reproduction or reduce survival, while also recognizing management requirements may vary among years depending on weather. Long-term studies are particularly valuable for the western prairie fringed-orchid due to its erratic life cycle and fluctuating populations, which complicate studies of environmental and management effects on this species. © 2015 American Midland Naturalist. Source

News Article | July 10, 2015
Site: http://www.techtimes.com/rss/tags/global-warming.xml

Bumblebees are having a hard time dealing with climate change, say researchers who express fear they could go extinct as suitable habitats for the insects shrink. Global warming is steadily reducing the areas where the bees — important pollinators of our food supplies — are found in both North America and in Europe, the scientists say. Writing in the journal Science, researchers, including Leif Richardson of the University of Vermont, report their examination of more than 420,000 current and historical records of a number of bumblebee species has confirmed steep declines in their numbers at continental scales. The loss of habitats will have an impact on more than just the bees, Richardson says. "Bumblebees pollinate many plants that provide food for humans and wildlife," he explains. "If we don't stop the decline in the abundance of bumblebees, we may well face higher food prices, diminished varieties, and other troubles." While many species such as butterflies are adapting to climate change by enlarging or shifting their habitats as temperatures change, that's not the case with bumblebees, the research team notes. Northern populations are staying in place, while those in southern habitats find those habitats retreating north away from the equator. That was unexpected, Richardson says. "The bees are losing range on their southern margin and failing to pick up territory at the northern margin — so their habitat range is shrinking," he says. Two other known major threats to healthy bumblebee populations — pesticides and changes in land use — aren't the culprit in the current case, the scientists say. The "range compression" of suitable bumblebee habitats is tracking exactly with warming global temperatures, they report. In the 110 years recorded in the data the researchers examined, bumblebees have lost around 185 miles from the southern edge of their habitat ranges in both North America and Europe. "The scale and pace of these losses are unprecedented," says study leader and biologist Jeremy Kerr from the University of Ottawa. One reason bumblebees are having trouble adapting to warmer temperatures could be explained by their evolutionary origins, says Alana Pindar, an ecologist at the Nature Conservancy of Canada. "Bumblebees originated perhaps some 35 million years ago in cool to temperate environments," she explains. "Most other species that have often shown positive responses to climate change, like butterflies, evolved in the tropics." The loss of habitat is a great concern, she says, because bumblebees pollinate more fruits, vegetables and flowers than the European honeybee does.

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