Ecosystem Threats and

Environmental Risks.

“Ranching in Brazil”

“Ranching in Brazil”

“Ranching in Brazil”

“Ranching in Brazil”►Pg. 120 – Question 7 (a) & (b)►7 (a) How has ranching disrupted fragile

relationships in the tropical rainforest ecosystem?

ANS: • Big areas of forest were cut down, and area

was replanted with non-native grasses.• Humidity balance affected and area was at

risk of erosion.• Many animals disappeared.• Soil destroyed and nutrients were lost.• The forest could not regenerate or sustain

itself.

►7 (b) The governments of some tropical countries now regularly set aside fragments of rain forests as conservation reserves. What problems do you see in this attempt at protecting the rain forest ecosystem?

ANS:• Isolated forests do not protect life forms living

in the area.• Large species need large areas (forced

inbreeding).• Wind and weeds threaten perimeter area.• Empty, outside area allows more access and

disruption of the ecosystem.

Climate Zones and Environmental Risk

►Tropical Climates►Dry Climates►Temperate Climates (mild winter/cold

winter)►Polar Climates►Highlands Climate

WHO CARES - DO YOU ?

►Desertification – the spread of desert-like conditions in semi-arid environments.

“Desertification in the Sahel”►Sahel is located along the Sahara

Desert.►Natural Environment:

• Hot, dry climate• 60-100mm falling during 1-3 months of

the year• Droughts are common

►Causes of desert advancement:• Fragile environment• Agricultural practices• Population growth

Analyze value positions taken on environmental issues.How would each of the following feel about a gold mine being developed in a local wilderness area – what is their position?1. President of a local environmental group.2. Owner of Regal Goldfields – mine developer.3. Owner of a local hunting lodge.4. Chief naturalist for the wilderness area.5. President of the local Fish and Wildlife Association.6. An unemployed fisherman.7. The wife of the fisherman – a part-time fish-plant

worker.8. The mayor of a local town.9. The owner of a local trucking company.10.The owner of a local restaurant.