Plant Communities and Habitats Affected by Recreation
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Alpine and Subalpine Meadows
The alpine areas of the province are found in high
mountains above 2000 metres in the southeast, above
1650 metres in the southwest, above 1400 metres in
the northeast, and above 1000 metres in the northwest.
These regions are treeless or nearly so, and the flora
is mainly shrubs, grasses, and flowering plants, mosses,
and lichens. Soil is often thin or nonexistent, and
easily damaged. Natural processes work slowly in this
environment and damage to habitat may take a long time
to be naturally repaired.
Primary source of information:
Alpine Tundra Zone. 1991. J. Pojar and A.C. Stewart.
In Ecosystems of British Columbia, edited by D. Meidinger and J. Pojar, pp. 263-274. B.C.
Ministry of Forests, Victoria, BC. Available from:
http://www.for.gov.bc.ca/hfd/pubs/docs/Srs/Srs06/chap18.pdf (PDF 33KB).
Riparian Ecosystems and Sensitive Wetlands
Riparian ecosystems are those areas adjacent to watercourses;
they provide a transition zone between upland and aquatic
ecosystems. The defining feature of the riparian environment
is close proximity to water. In the drier parts of
the province, the riparian zones are often the only
places moist enough to support the growth of trees
and shrubs. In much of the province, riparian zones
are subject to flooding during spring runoff and winter
rains.
Riparian ecosystems cover only a small portion of
the forest land in a watershed, but because they are
often more diverse and productive than upland areas,
they provide critical wildlife habitat.
Forest riparian ecosystems have an important role
in stabilizing streambanks, regulating stream temperature,
and filtering out potentially harmful debris and pollutants.
They produce a high diversity of plant species, which
provide many opportunities to wildlife for nesting,
feeding, hiding, roosting, and use as migration corridors.
Forest riparian ecosystems also are a source of large
woody debris that falls into streams, providing structural
stability, complexity, and nutrients to aquatic ecosystems.
Necessary permits and/or licences with specific legal
conditions related to water must be obtained for road
and trail development, commercial water use, sewage
disposal, and water diversion for hydroelectric power
development.
Primary sources of information:
Cottonwood Riparian Ecosystems of the Southern Interior
(Ecosystems in British Columbia At Risk). 1997. B. Egan, C. Cadrin, and S. Cannings. B.C. Ministry
of Environment, Lands and Parks, Victoria, BC. Available
at
http://www.env.gov.bc.ca/wld/documents/cottonwood.pdf (PDF 526KB)
Environmental Trends in British Columbia. 2000. B.C.
Ministry of Environment, Lands and Parks, Victoria,
BC. Available at:
http://www.env.gov.bc.ca/soe/reports/enviro_trends2000.pdf (PDF 4.92MB)
Riparian Ecosystems. 1995. A.K. Andrews, and G.T.
Auble. In Our Living Resources: A Report to the Nation
on the Distribution, Abundance, and Health of U.S.
Plants, Animals, and Ecosystems edited by E.T. LaRoe,
et al. National Biological Service, Washington, DC.
Wildlife Trees and Coarse Woody Debris
The importance of wildlife trees (what used to be
called “snags” or “dead standing
trees”) and coarse woody debris (also called “downed
wood”) in the conservation of biodiversity cannot
be underestimated. More than 80 species of wildlife
in B.C.—many of which are Red- and Blue-listed
species—make their homes in wildlife trees or fallen, rotting wood. These
species include:
Primary cavity excavators – birds, such as woodpeckers,
sapsuckers, nuthatches, and chickadees that excavate
their own nest holes in trees.
Secondary cavity users – species such as owls,
salamanders, and squirrels that cannot excavate their
own cavities but rely on natural cavities or abandoned
nest holes for nesting and denning sites, shelter,
and food storage.
Downed wood is a “savings account” of
nutrients. As downed wood decays, nutrients are recycled
back into the soil. Fallen logs also stabilize soils
and reduce erosion by wind, rain, and melting snow.
As well as being a source of food and energy, downed
wood may be a safe place to hide from predators, or
to breed, or to shelter from heat, cold, and storms.
Loose bark and cracks in decaying wood are safe hiding
places for salamanders, skinks, voles, shrews, and
shrewmoles. Hollow logs provide shelter for bears,
raccoons, weasels, hares, and woodrats. Amphibians,
snakes, voles, and mice burrow into well rotted, disintegrating
logs to nest or hid. Large logs help stabilize stream
channels and create a series of pools alternating with
rapidly flowing water. Some birds, such as Harlequin
Ducks, use streamside logs for breeding sites.
Fallen logs are also excellent nurseries for plants. “Nurse
logs” can provide greater warmth, longer snowfree
periods, less competition from other plants, more moisture,
and sometimes more nutrients than the surrounding forest.
Soil and other organic matter that tend to gather uphill
behind fallen logs also create rich, sheltered growing
sites.
In estuaries, downed wood enriches the habitat for
many species, and along the coastline beached logs
stabilize sand spits, beaches, and dunes.
For more information, see:
Rotten luck: The role of downed wood in ecosystems
[pamphlet]. B.C. Ministry of Forests, Victoria, BC.
Available at
http://www.for.gov.bc.ca/hfd/pubs/Docs/Bro/bro24.pdf (PDF 543KB).
Firewood or Wildlife Tree? B.C. Ministry of Forests,
Victoria, BC. Available at
http://www.for.gov.bc.ca/hfp/publications/00036/Fire.pdf (PDF 133KB).
Wildlife trees and coarse woody debris publications
and products, B.C. Ministry of Forests, Victoria, BC.
Available at
http://www.for.gov.bc.ca/hfp/values/wildlife/cwdlib.htm
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