Our Forests & Oceans
Forests: cover 30% of the earth’s land surface
*World consumes approximately 3.5 billion tons of wood per
year
50% USED FOR INDUSTRIAL TIMBER:
- construction products
- lumber
- plywood
- pulp & paper
- particle board
50% USED FOR COOKING FUEL!
Source: FAO
A. State of World Forests:
Temperate forests are increasing in area
 reforestation in U.S./Canada & W. Europe
Tropical forests are decreasing in area
 deforestation in Amazon, Congo, S.E. Asia
 https://www.youtube.com/watch?v=oBIA0lqfcN4
- developing countries lose 2% of forests a year
B. Reasons for deforestation:
1. Shifting Cultivation: slash & burn
2. Commercial purposes:
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convert land to agriculture (Brazil & Indonesia)
wood harvested for pulp & lumber (commercial)
metals, minerals, oil exist below the forests
Overall: poor government management
https://www.youtube.com/watch?v=M4jhjt1_eyM
 10,000 years ago: 6 billion acres of tropical rainforests
 1950: 2.8 billion acres
 Today: Less than 1.5 billion acres left
 At this rate: no tropical forests left in 30 years!
Tropical rainforest
destruction
C. Environmental Consequences
1.Increase in Global warming & CO2 emissions
2.Each day about 80,000 acres of forests disappear
3.Ozone depletion
4.Deforestation rates HAVE NOT slowed
Increase in Tropical Deforestation Around the World
World Fisheries:
 87% of commercial fish catches are from our oceans
1950: 22 million tons of fish caught
1989 catch: 100 million tons
A. Ocean Issues
 Overfishing
 Dead Zones: low levels of dissolved oxygen
(hypoxia)
 Health of coral reefs
As of 2007…
 28% of monitored stocks are overexploited, depleted, or
recovering from depletion.
 52% are fully exploited (producing catches at or close to
maximum sustainable limits with no room for expansion)
“Rebuilding North Atlantic Swordfish, a Report for the U.S. Congress and the
Administration” 1998, Recreation Fishing Alliance
Declining Shark Populations
https://www.youtube.com/watch?v=tAzxkDQFPe0
B. Coral Reefs
1. Negatively impacted by:
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Global warming
Urban run-off
Bleaching
Development
 https://www.youtube.com/watch?v=eIul2ObvKV8
 http://video.nationalgeographic.com/video/coralreefs
Global Distribution of Reefs
Coastal Development
Hanauma Bay: Hawaii
• Millions of tourists nearly destroyed it between the 1960s-80s.
• Closed on Tuesdays to let wildlife feed unimpeded by tourists
• Visitors must watch a 9-minute video before visiting for the first
time.
Oceanic Dead Zones & Ocean Pollution
https://www.youtube.com/watch?v=XEZpo9uLIc0
Source: UNEP Geo Year Book 2003
http://oceantoday.noaa.gov/happnowdeadzone/
C. Is Aquaculture the Answer?
1. Mangroves are being
replaced by shrimp & fish
farms
2. Mangroves provide:
- storm protection
- fish nurseries
- bird habitat
Mangroves Replaced by
Shrimp Farms
Shrimp farms replacing mangroves in
Gulf of Fonseca, Honduras
1987-1999: shrimp farms
and ponds have
mushroomed, carpeting
the landscape around the
Gulf of Fonseca, in blocks
of blue and black shapes