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British Columbia is the most ecologically diverse province
in Canada; a diversity that is primarily determined by its unique
macro-climate and topography. This biodiversity has been the
basis for a rich array of subsistence, spiritual, recreational
and economic non-timber forest products. Non-Timber Forest Products
(NTFPs) are all of the botanical (plant) and mycological (mushroom
& fungus) resources and associated services of the forest
other than timber, pulpwood, shakes, or other conventional wood
products.
Human activities have modified natural ecological processes
with varying impacts on these resources. To manage NTFPs effectively,
we need to understand the ecosystems within which they occur.
There are two important keys to this understanding.
The first key is ecological zonation, of which the most widely
used system in B.C. is the Biogeoclimatic Ecosystem Classification
(BEC). Here is the website for a BEC map that will show you
the current ecological zonation for British Columbia: http://www.for.gov.bc.ca/hre/becweb/bec-view.htm
BEC incorporates climate, soil, topography and vegetation data
to produce an integrated, hierarchical classification consisting
of:
- zonal units based on climatic climax vegetation;
- sub-zone units based on moisture; and
- site/ecosystem units describing how the composition of ecological
communities changes over time on specific areas.
BEC supports predictions of what plants will occur on undisturbed
landscapes across zones and subzones, and judgements on site
productivity, vegetation succession after disturbance, species
for ecosystem recovery, and wildlife habitat capability.
The second key is the concept of Natural Disturbance Regimes
(NDRs). The NDR in any area largely determines species composition,
vertical canopy architecture and spatial structure of ecological
communities over time. BEC zones and sub-zones are the end result
of the prevailing disturbance regimes. NDRs help us understand
the manner in which ecosystems have changed when human activities,
often associated with single-purpose management, have modified
the nature, intensity and frequency of disturbance. NDRs also
give us some hints about the measures that might be used to
re-introduce more natural, multi-purpose ecosystem management
practices.
There are three general categories of NDRs:
- gap-driven ecosystems resulting from rare
stand-initiating events,
- disturbance-driven ecosystems resulting
from frequent stand-initiating events, and
- disturbance-maintained ecosystems resulting
from frequent stand-maintaining events.
In this module, you will learn about disturbance-maintained
ecosystems — what they are, where they occur
in British Columbia, how they relate to BEC zones, and some
of the non-timber forest products that commonly grow in them.
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