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How do we use it?How do we use it?
1. timber for paper, furniture, and home construction
1. timber for paper, furniture, and home construction
2. rich grassland to support livestock & farms
2. rich grassland to support livestock & farms
3. mineral resources to make everything (from electronics to engine power, etc.)
3. mineral resources to make everything (from electronics to engine power, etc.)
worldwide avg.: 1,800 cubic cm.
of wood per person each day.
worldwide avg.: 1,800 cubic cm.
of wood per person each day.
We use 3.5 times the average in the US.
Each year, one person cuts down a 30 m tall tree.
We use 3.5 times the average in the US.
Each year, one person cuts down a 30 m tall tree.
clearing trees from an area without replacing them.
clearing trees from an area without replacing them.
process of removing all trees
from an area
process of removing all trees
from an area
Disadvantage:Disadvantage:destroys wildlife,increases soil erosion; diminishesbeauty
destroys wildlife,increases soil erosion; diminishesbeauty
XX
Advantage:Advantage:least expensive,
fewer roads needed.
least expensive, fewer roads
needed.
cutting only middle-aged or
mature trees
cutting only middle-aged or
mature trees
Disadvantage:Disadvantage:expensive; more
roads cause more soil erosion.
expensive; more roads cause
more soil erosion.
Advantage:Advantage:less impact on
environment than clear-cutting
less impact on environment than
clear-cutting
Process of replacing trees
that have died or been cut down.
Process of replacing trees
that have died or been cut down.
Rangeland - essential for maintaining the
world’s food supply.
Rangeland - essential for maintaining the
world’s food supply.
ProblemsProblemsa. overgrazing - dry patches left or unwanted plants take over.b. desertification
a. overgrazing - dry patches left or unwanted plants take over.b. desertification
Public Rangelands
Improvement Act of 1978
Public Rangelands
Improvement Act of 1978
grazing management: a. limits animal herds
to sizes land can support
grazing management: a. limits animal herds
to sizes land can support
b. move herds in a way that will
protect the plants that support them.
b. move herds in a way that will
protect the plants that support them.