Human Impact

1. Human Impact

2. Human Impact • As the human population grows, more and more strain and changes are imposed on our environment. • As we have learned our world and the ecosystems within it require balance and are fragile to abrupt changes. • In order to prevent irreversible changes we have to understand the causes of environmental change and the effects these changes will have on future generations.

3. Causes - Agriculture • Fishing – Overfishing and pollution contribute to changes in aquatic ecosystems. • Crop production – Pesticides and Herbicides alter the carbon, nitrogen and phosphorus cycles. • Meat production – Land degradation (deforestation), Methane production (green house gases), and disease. • Introduction of invasive species as a way of dealing with pests.

4. Causes - Energy • Fossil fuels directly pollute the environment and contribute to global warming. • Nuclear plants pollute water with radioactive waste. • Damns destroy habitat and ecosystems. • Wind turbines kills animals.

5. Causes - Manufacturing • Household chemicals damage aquatic and terrestrial ecosystems. • Technological waste is poisonous and some components cannot be recycled. • Paper production produces green house gases.

6. Causes - Manufacturing • Pharmaceuticals and beauty products damage aquatic ecosystems and may cause direct consequences to users (see DDT video). • Paint additives are poisonous to people and the environment

7. Causes - Mining • Erosion • Sinkholes • Loss of wildlife • Contamination of soil and water • Logging

8. Causes - Transportation • The use of oil based fuels causes green house gases (Carbon dioxide) and global warming. • Acid rain (change in pH of water) and smog. • Increase in population = increase in transportation needs.

9. Causes - War • Biochemical weapons pollute and kill. • Wildlife and habitat destruction. • Nuclear waste and disposal.

10. Effects – Habitat Destruction • Animal homes are destroyed. • Animals must search for new homes. • If an animal must change biomes it probably will not adapt and die. • Food webs are changed and some animals cannot cope with the change.

11. Effects – Coral Reefs • Coral reefs = fish habitat. • 70% of coral reefs are either destroyed or endangered (nearly destroyed). • Marine ecosystems cannot survive without coral reefs.

12. Effects - Extinction • Damaging the environment and habitat leads to loss of wildlife and biodiversity (a decrease in variety of wildlife). • Extinction (complete loss) of species occur. • Changes in food webs that sometimes lead to further extinction of other species or imbalances in nature.