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4.6 Utilization of Forest Resources
By Lester Green Smallwood Academy Gambo
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4.6.1 Compare the terms clear-cutting and selective cutting.
Clear-cutting Harvesting of all
timber and unwanted species.
It leaves only stumps and rubbish on the ground.
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4.6.1 Continued…Selective cutting Harvesting of
selected trees individual or small groups of mature trees are cut, leaving most of forest intact.
Often carried out in deciduous forest or mixed species and age.
4.6.1 continued…
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4.6.2 Compare the advantages and disadvantages of each approach.
Clear-cutting:
Advantages Most rapid method Most economical Least dangerous
Clear-cutting:
Disadvantages Trees
removed/burned Ecosystem struggles
to recover Habitat destroyed Soil more easily
eroded
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4.6.2 Compare the advantages and disadvantages of each approach.
Selective Cutting
Advantages Younger trees grow
to maturity Far less ecological
disruptive
Selective Cutting
Disadvantages Yields are lower More expensive Access roads must
be maintained
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4.6.3 Major threats to forest resources.Deforestation (see #7 p. 163)
agricultural land
housing needs
mineral deposits
hydro-electric development
4.6.3 continued…Forest Fires Insects (spruce
budworm, hemlock looper)
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4.6.4 Examine strategies for a sustainable forestryLimiting clear-cut plotsSkyline Yarding system (case study p.
166)Use of HelicoptersReseeding/ better refrigeration for seedsLimit number of trees per hectareSecondary processing to increase
employment
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4.6.5 Evaluate a position taken on a given argument about timber harvesting.
See question # 11, p. 169Case Study: Clearcutting Controversy
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4.6.6 Infer a relationship between climate and the extent of forest cover. Tundra region to cold with frozen soil and small
amounts of precipitation Desert regions to hot and small amounts of
precipitation Grassland regions not enough precipitation to
support any amount of tree growth
Percentage of forest cover fig 10.1, p. 162
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4.6.6 continued… Three regions with forest cover1. Boreal Forest Region Cold, moist climatic region
with short growing season.
Evergreen coniferous (needle-leaf) such as spruce, fir, pine, etc..
Location…across North America and Eurasia
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4.6.6 continued… Three regions with forest cover2. Deciduous Forest
Region Temperate climatic area
with cool and moist conditions.
Loose leafs during winter months
Broadleaf trees…examples oak, maple, birch, etc.
Location…W Canada, W & S USA, W Europe, SE Asia
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4.6.6 continued… Three regions with forest cover3. Tropical Rainforest
Regions Equatorial region with hot
and moist climatic conditions
Evergreen broadleaf such as teak, mahogany
Location…NE South America, India, SE Asia, Indonesia, Africa, etc. (tropical regions)
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4.6.7 Analyze global patterns in the depletion of forest resourcesSee fig 10.2, p. 164