Chapter 1 - Notes

Understanding Our Environment 1.1

All life on Earth exists in the biosphere - it extends about 8km into the atmosphere, where insects, bacteria and pland seeds may be found, ans as much as 8 km into the ocean.

Three categorgies that all environmenetal problems fall into are; Resource depletion, pollution and extinction.

 Examples -

 Resource Depletion - the rapid consumption of fossil fuels

• Nonrenewable resources are things like fossil fuels, iron, and precious metals
• to avoid running out of nonrenewable resources like copper, we must use them wisely and recylcle whenever possible
• renewable resources are things like, wind, sun and trees
• If we use renewable resources no faster than nature replaces them, there may be enough of these resources in the future.

 Pollution - contamination of wayerways by pesticides

• The amount of carbon dioxide in our planet's atmosphere is increasing, which may cause the climate of the Earth to change.
• Trees and other plants revmove carbon dioxide from the air

 Extinction - The death of all passenger pigeons

• The bald eagle was once on the brink of extinction.  Today it is making a comeback, thanks to efforts to preserveits habitat and reduce pollution fromteh pesticide DDT

Why our Main Environmental Problems

• The population crisis is the result of human opulation growing larger than the Earth can support.
• Consumption crisis is the result of people using, wasting or polluting natural resources faster tha they can be renewed, replaced or cleaned up.
• Developed nations are most affected by consumption crisis - where resources are used up, wasted or polluted faster than they can be renewed, replaced, or cleaned up
• Developing nations account for most of the population crisis -  where human populations are growing too quickly for the regions to support
• Three ways to maintain a sustainable environment; preserving habitats, converting garbage into harmless substances, using nonrenewable resources no faster than they can be replaced