Ecosystems Ecosystem threats and environmental risks.

“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 the areas were 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 outside 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 and WHO DON’T ????

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