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Biogeoclimatic Ecosystem Classification
(BEC) is a system that groups similar
segments of the landscape (ecosystems)
into categories of a hierarchical classification
system. An ecosystem is the product
of a complex interaction of vegetation,
animals, microorganisms, and the physical
environment. For purposes of BEC, an
ecosystem is defined as a particular
plant community and its associated topography,
soil, and climate. While boundaries
between ecosystems in the landscape
can be abrupt, they more often tend
to be gradual.
Climate is the most important factor
influencing the development of forest
ecosystems. The Douglas-fir forests
around Nanaimo reflect a much warmer,
drier climate than the moist red cedar-hemlock
forests on the west coast or the snowy
mountain hemlock forests at high elevations.
Within each of these climatic areas,
ecosystems vary because of differences
in topography and soil. Rocky ridges
are relatively drier than lower slopes
and valley bottoms.
Vegetation is important when developing
the ecological classification because
it is readily visible, and it reflects
the environment, biology, and history
of a site. However, vegetation changes
over time following disturbance - a
process called succession. It is the
more stable vegetation from later successional
stages ("late seral" or "near climax")
that the classification is developed
from and that are most useful for identifying
ecosystems, although BEC can also be
applied to earlier successional stages.
More information about BEC - history,
methods, applications, publications
- is available at the ministry
Research Branch.
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The best way to learn about BEC is
to take an introductory BEC training
course. For course dates and details,
please contact the Coast Region ecologists.
The Coast Region ecosystem classification
is described in two field guides, both
available on-line:
Both can also be purchased in field-ready
(waterproof) format from
Crown Publications
BEC classifies British Columbia into
broad regions of homogeneous climate
(biogeoclimatic units). Within these
climatic units various ecosystem types
(site units) are described.
Biogeoclimatic units are identified
using biogeoclimatic unit maps as well
as vegetation features, elevational
ranges, and other information presented
in field guides.
District-level biogeoclimatic unit
maps for the Coast Region are available
here. Provincial-level digital maps
for download are available at the
Research Branch's BEC site
Site units are identified using the
field guides mentioned above, and are
mapped using
Terrestrial Ecosystem Mapping (TEM)
and Predictive Ecosystem Mapping (PEM).
TEM and PEM for the Coast Region are
available
here.
BEC is the main ecosystem classification
used in forest and range management
in BC. It is often used in conjunction
with the
ecoregion classification, which
stratifies British Columbia's terrestrial
and marine ecosystem complexity into
Ecodomains, Ecodivisions, Ecoprovinces,
Ecoregions and Ecosections. These units
describe areas of similar climate, physiography,
oceanography, hydrology, vegetation
and wildlife potential.
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