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Silviculture--Deforestation

Silviculture--Deforestation. Forestry & Society HORT/RGSC 302 Fall 2007. Forestry & Society World Forests & Land Use/ Pop. Act. Int’l 1999. Billions. Forestry & Society Loss of World Forests/ Stanturf & Madsen Plt Biosys 136(2):143:2002. Loss of Original Forest Cover (%). 6 kkk ha.

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Silviculture--Deforestation

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  1. Silviculture--Deforestation Forestry & Society HORT/RGSC 302 Fall 2007

  2. Forestry & SocietyWorld Forests & Land Use/ Pop. Act. Int’l 1999 Billions

  3. Forestry & SocietyLoss of World Forests/Stanturf & Madsen Plt Biosys 136(2):143:2002 Loss of Original Forest Cover (%) 6 kkk ha 3.45kkk ha

  4. Forestry & SocietyHuman Impacts on Forests • Places we have clearcut!!! • Middle East • Iceland • Easter Island • Chaco Canyon

  5. Forestry & SocietyHuman Impacts on ForestsEaster 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

  6. Forestry & SocietyHuman Impacts on Forests Chaco Canyon • Anasazi inhabited 850-1250 AD • Center of culture • Multi-storied home sites • Clearcut region and abandoned sites

  7. Where have all the trees gone? 50 most forested countries 21 22 4 3

  8. Forestry & SocietyChanges in Forest Cover (1980-1990)/ FAO 1997 % Change

  9. Forestry & SocietyThreatened Original forests-The Africa & Russia/WRI 1997 Second growth forests Low to no threat Medium to high threat

  10. Forestry & SocietyThreatened Original forests-The Americas/WRI 1997 Unknown Low to no threat Medium to high threat Second growth forests

  11. Forestry & SocietyWorld Forest Loss/ Pop. Act. Int’l 1999 Forest to Farmland Loss Model Population Growth and Resettlement

  12. Forestry & SocietyWorld Forest Loss/ Pop. Act. Int’l 1999 • Underlying Causes • Population Change • growth • density • migration • Economic Growth • rising income • dietary change • housing preference • Poverty • Market failures • forest valuation • Policy Failures • population resettlement • corruption • Direct Causes • Agricultural clearing of forests • subsistence agriculture • commercial farming • cattle ranching • Industrial logging • Infrastructure & industrial development • roads • dams • mining • housing • Fuelwood & charcoal production

  13. Original Forest Cover Present Forest Cover Forestry & SocietyTropical Deforestation/ Sharma 1992

  14. Forestry & SocietyTropical 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

  15. Forestry & SocietyTropical Deforestation/Brazil Deforestation (km2/yr) The For.Sourc. #10 7/05

  16. 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 Forestry & SocietyTropical Deforestation/Cuba Tocororo bird http://www.rcfa-cfan.org/english/profile.20.htm

  17. Deforestation in Haiti 1492 = 75% Forested 1998 = 1% Forested A young girl carries pine branches torn from trees in La Visite Park, a reserve outside Port-au-Prince. A truck carrying peasants and bags of freshly made charcoal rumbles through the Pine Forest Reserve. DANIEL MOREL/SPECIAL TO THE HERALD

  18. Forestry & SocietyTropical Forests- Deforestation / Thailand Longman & Jenik 1987 Shaded = Deforested 18 yrs

  19. Deforestation in China • 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

  20. Forest Cover (%) Year Deforestation in China Zhang et al. Res. for Fut. 2003 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

  21. In northwest China, the Taklimakan's sands are shifting toward poplar trees planted west of Aksu in a vast project intended to halt desertification. • 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

  22. Forestry & SocietyTropical Forests- Deforestation Affects/ Longman & Jenik 1987 Run-off (ml/m2) Soil loss (g/m2) Thailand >20 mm/hr 6 4 <10 mm/hr 2 0 Canopy Cover (%)

  23. Forestry & SocietyDeforestation • Things to Know • What is deforestation? • What are direct and indirect causes of deforestation? • What are some of the effects of deforestation? • How would you solve the problem of deforestation?

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