Chapter 3

Section 2

Forest Resources

• Flowers, fruits, seeds, and other parts

• Maple syrup, rubber, and nuts living trees

• Construction and paper Pine and spruce

• Furniture Oak, cherry, and maple (Hardwoods)

Importance of Plants

• Produce oxygen

• Absorb carbon dioxide

• Absorb pollutants

• Prevent flooding and soil erosion

Management of Forests

• 300 million hectares of forest in the US

• Many on public land– Privately owned are used for timber and paper

companies – 1.5 million jobs

• Trees are renewable

Logging Methods

• Clear-cutting:– Cutting down all the trees in an area at once

• Selective Cutting:– Cutting down some trees in a forest leaving a

mix of tree sizes and species

Clear-Cutting

• Quick

• Cheaper than selective

• Safer

• Exposes soil to wind and rain

• Soil is washed into nearby streams disrupting ecosystems

Selective Cutting

• Move heavy equipment and logs

• Less damaging to the forest

• Habitat doesn’t change as much

Sustainable Forestry

• Sustainable yield:– Regular amount of a

renewable resource such as trees that can be harvested without reducing the future supply.

– Plant a tree to replace a tree cut down

• Soft wood trees mature faster than hardwood trees (hickory, oak, and cherry)

• Pine harvest every 20-30 years

• Hardwood 40 to 100 years

Certified Wood

• Forest Stewardship Council – Forests managed in a sustainable way

• All wood logged must carry a well-managed label

Fisheries

• Are fish an unlimited resource?– The number of sardines off the California

coast has declined– Also happening to school of cod off the New

England coast

Fisheries

• Fishery:– Area with a large population of valuable

ocean organisms

– Grand Banks off Newfoundland– George Banks off New England– Monterey Canyon off California

Fisheries

• Managing fisheries for sustainable yield– Setting fishing limits– Changing fishing methods– Developing aquaculture techniques– Finding new resources

– 70% of the world’s fisheries have been over fished

Fishing Limits

• Protect individual species

• Limit the amount caught

• Require a certain size

• Fishing can be banned in areas too

Fishing Methods

• Nets with larger mesh to allow smaller fish to get out

• Outlaw methods– Poisoning fish with cyanide– Stunning them by exploding dynamite

• Kill all fish rather than specific fish

Aquaculture

• Aquaculture:– Raising fish and other water-dwelling organisms for

food

– May be raised in ponds or bays

– Salmon, catfish, and shrimp U.S.

– Maintaining the artificial ponds and bays can cause pollution and spread disease into wild fish populations

New Resources

• 9,000 different fish species are harvested for food

• Helps feed a growing population

• Trying to introduce people to deep-water species and tile fish

• Try to use easy-to-farm freshwater fish tilapia

Another sustainable method

• Green roofs