Forestry & Society
Boreal Forests:Outline
• Definition
• Diversity
• Important Species
• Carbon budgeting
Forestry & Society
World Forest Zones/ Sharma 1992
Boreal
Temperate mixed
Temperate evergreen
Tropical rain
Tropical deciduous
Tropical dry
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Species Diversity- Tree Species
• Canada >50oN Picea (4 species) • Canada >45oN Pinus (9 species)• USA 25-50oN Pinus (37 species)• Mexico 15-30oN Pinus (80 species)• Brazil 10oS 100’s species /ha• Tierra del Fuego55oS Nothofagus (3
species)
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Boreal Forests: Definition– Northern Arctic Forests
• 15% of land surface area
– Location: >45oN latitude• also Nothofagus forests in So. Amer. & NZ
– Precipitation:40-90 cm(15-35”)[snow] – Temperature: mean annual T =-3 to -10oC– Soils: highly glaciated, thin
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Boreal Forests-Growth Comparison
25 mm
Black Spruce 163 yrs Eucalyptus 2yrs
25 mm
Forestry & SocietyBoreal Forests-Important Canadian-US Species
• Black spruce (Picea mariana)
• White spruce (Picea glauca)
• Balsam fir (Abies balsamea)
• Jack pine (Pinus banksiana)
• Aspen (Populus tremuloides)
• Tamarack (Larix laricina)
• Paper birch (Betula papyifera)
Forestry & Society SE Alaska Forests (Tongass NF) /PNW-GTR 609, 2004
4.1 21%7
35%
4 21%
4.4 23%
Timberland
Reserved
Shrub
Ice/snow
Forestry & Society SE Alaska Forests /PNW-GTR 609, 2004
Forest Type
AK cedar/Hemlk
LPP Mixed conifer
Mtn Hemlk
Sitka spruce
Hemlk Sit sp
WRC Hemlk
Hemlk
Ac (k) 110 10 500 200 250 680 400 1280
Vol (kk ft3)
400 50 2200 750 1300 3800 1800 7250
Productive (%)
32 0 40 27 93 84 65 92
Ann Vol (kk ft3)
4 0 20 7 20 37 20 60
Forests of Russia/J.For. 101(4):34:2003
Boreal forest/taigasTemperate broadleaf
& mixed forests
Temperate conifer forest
0
50
100
150
200
250
300
350
400
1965 1970 1975 1980 1985 1989 1990 1995 1996 1997 1998 1999
Wood Harvest
Forests of Russia/J.For. 101(4):34:2003
Year
Removal (KK m3/yr)
Major Species:Pinus silvestris, Larix sibiricaLarix gmelinii, Picea obovataAbies sibirica, Pinus sibiricaBetual pendula, Populus tremula
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Boreal Forest of North AmericaNatural Regeneration of black spruce
Science Findings 40:2001
~5cm/yr
~15cm/yr
Forestry & SocietyBoreal Forests-Important Canadian-US Species /Coombes 1992
Picea marianaBlack spruce
Forestry & SocietyBoreal Forests-Important Canadian-US Species/Coombes 1992
Betula papyriferaPaper birch
Forestry & SocietyForests of the World/ Litter & nutrient residence time (yrs)/Kozlowski & Pallardy 1999
Forest OM N P K Ca Mg
Tropical 0.7 0.6 0.6 0.2 0.3 --
Temperate deciduous 4 6 6 1 3 3
Temperate coniferous 17 18 15 2 6 13
Boreal deciduous 26 27 15 10 14 14
Boreal coniferous 350 230 324 94 150 455
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Forest Productivity Comparison
Forest Biomass(t/ha)
Net PrimaryProductivity(t/ha)
Tropical 450 20Temperate 240 10Boreal 225 5Woodland 100 6Ag land 35 7
Climate Change in Boreal Forests/ www.whrc.org/resources/published_literature/pdf/BunnetalEarthInt.06.pdf
Strong PositivePositiveNear ZeroNegativeStrong Negative
0.60
0.70
0.50
1980 1990 1995 2000 20051985
Ps (Pg/yr)
Annual Fires (AK and NA)
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Boreal Forests--Review Questions
• Compare and contrast the carbon budgets of a tropical, temperate, and boreal forest. Don’t memorize numbers, just give concepts and relative differences.
• What is a boreal forest? Where does it occur? What is the climate?
• What are some of the major species in a boreal forest?