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Forestry & Society
World Forests & Land Use/ Pop. Act. Int’l 1999
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6000BC 0 AD1000 1500 1800 1900 1950 1990 2000 2010
Forest landCroplandPopulation
Billions
Forestry & Society
Loss of World Forests/ Stanturf & Madsen Plt Biosys 136(2):143:2002
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Asia-Pacific Africa Europe LatinAmerica
NorthAmerica
Loss of Original Forest Cover (%)
6 kkk ha
3.45kkk ha
Forestry & Society
Human Impacts on Forests
• Places we have clearcut!!!– Middle East – Iceland– Easter Island– Chaco Canyon
Forestry & Society
Human Impacts on Forests Easter Island
• ‘Discovered’ by the Dutch in 1722– Barren, eroding wasteland with few
people (~2,000) and no trees, but huge monoliths (14-80 tons)
• Polynesians arrived ~400 AD– forest included 80 ft palms (for
skids), hauhau tree (for rope), and toromiro (for fuelwood)[pollen analysis]
– population grew to ~20,000 (hunted dolphin from canoes)
– last tree cut about 1400--population declined, but couldn’t leave!
J. Kaspersen, Erosion Control 8(2)Mar/Apr:6: 2001
Forestry & Society
Human Impacts on Forests Chaco Canyon
• Anasazi inhabited 850-1250 AD– Center of culture– Multi-storied home sites– Clearcut region and abandoned
sites
Forestry & SocietyThreatened Original forests-The Africa & Russia/ WRI 1997
Low to no threat
Medium to high threat
Second growth forests
Forestry & Society
Threatened Original forests-The Americas/ WRI 1997
Low to no threat
Medium to high threat
Second growth forests
Unknown
Forestry & Society
World Forest Loss/ Pop. Act. Int’l 1999
Land Degradation
Land Abandonment
Forest Clearing
Migration
Population Growthand Resettlement
Forest to Farmland Loss Model
Forestry & Society
World Forest Loss/ Pop. Act. Int’l 1999
Underlying CausesPopulation Change
growthdensitymigration
Economic Growthrising incomedietary changehousing preference
PovertyMarket failures
forest valuationPolicy Failures
population resettlementcorruption
Direct CausesAgricultural clearing of forests
subsistence agriculturecommercial farmingcattle ranching
Industrial loggingInfrastructure & industrial development
roadsdamsmininghousing
Fuelwood & charcoal production
Forestry & Society
Tropical Deforestation/
• Worldwide = 3 KKK ac of tropical forests– <5% sustainably managed– Latin America = 1.3 KKK ac (27KK ac protected)
• Brazil (975 KK ac of tropical forest land) [For.Sourc. #10 7/05]
– Loses > 6.2 KK ac/yr to deforestation
– Has lost > 17% of tropical forests
– In 2000, 33 KK ac planted to soybeans
– Asia & Pacific = 415 KK ac (48KK protected)
– Africa = 272 KK ac (14.8KK protected)L.J. Adams Alb. J. 5/27/06 p.A8
Forestry & Society
Tropical Deforestation/Brazil
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1988 1989 1990 1991 1992 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004
km2/yr
Deforestation (km2/yr)
The For.Sourc. #10 7/05
Forestry & Society
Tropical Deforestation/Cuba
• 1600 > 90% forest• 1959 < 14% “• Today ~ 24% “
• 2,618,700 ha (~90% native)• 126 kk m3 (+7.5 kk m3 /yr)
– Harvest 1.6 kk m3 /yr (65% fuelwood)
– ~40,000 workers
http://www.rcfa-cfan.org/english/profile.20.htm
Tocororo bird
Deforestation in Haiti
A truck carrying peasants and bags of freshly
made charcoal rumbles through the Pine Forest Reserve.
DANIEL MOREL/SPECIAL TO THE HERALD
A young girl carries pine branches torn from trees in
La Visite Park, a reserve outside Port-au-Prince.
1492 = 75% Forested1998 = 1% Forested
Forestry & SocietyTropical Forests- Deforestation / Thailand
Longman & Jenik 1987
Shaded = Deforested
18 yrs
• Land Area = 11.86 billion ha– 16.5% forested (1.96
billion ha)– 11 Western provinces
= 9.06% forested– 5 NW provinces =
3.34% forested– 1/3 of country faces
serious erosion
• Population ~ 1.2 billion people– 400 million affected by
deforestation
Deforestation in China
Hainan island• 3.4 kk ha • 370 k ha rubber tree• 130 k ha eucalyptus
– 4% ↑ in forest cover
• 6-8% of island has been reforested or rehabilitated
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1930 1950 1970 1980 1995
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Forest Cover (%)
Deforestation in China Zhang et al. Res. for Fut. 2003
• 42 billion trees have been planted since 1982
• number of sandstorms has grown from 5 in the ‘60's to 24 in the ‘90's
• deserts are expanding at a rate of 3,800 square miles a year
Stuart Isett/Polaris, for The New York Times
In northwest China, the Taklimakan's sands are shifting toward poplar trees planted west of Aksu in a vast project intended to halt desertification.
Forestry & Society
Tropical Forests- Deforestation Affects/ Longman & Jenik 1987
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25 45 55 65 75 85
Soil loss Soil loss
Run-off Run-off
Run-off (ml/m2) Soil loss (g/m2)
6
4
2
0
Canopy Cover (%)
>20 mm/hr
<10 mm/hr
Thailand