 Natural
 Unnatural
◦Global Warming
Increase in concentration of a pollutant
from 1 link in a food chain to another
Due to –
Bioaccumulation: increase in
concentration of toxins in an organism
or population
- DDT & Eagles
Even small amounts of toxins can make it into
organisms in high enough levels to cause
Pollutants have in common:
• Long – lived
• Mobile
• Soluble in Water
• Biologically active
• Heavy metals like lead & mercury
Removal of indigenous forests & woodlands
Results in:
• Alteration of Local and global climates
• Global warming
• Drier Climate (less plants, land holds less
• Soil Degradation (erosion & silting of water)
• Extinction/loss of Species
• Desertification
• Urban Development
• Increased Farming
Process where bodies of
water receive excess
nutrients that stimulate
excessive plant growth
- Especially
Causes of Global Warming
• Deforestation
• Pollution
• Natural Causes/Sources
Results of Global Warming
Ave. Temperatures have risen
Arctic Ice Disappearing
Coral Reefs Bleaching due to
warmer ocean
More extreme weather events
(wildfires, heat waves, tropical storms)
Glaciers Melting

Causes of Unbalanced Ecosystems