Definitions Environment –The combined abiotic and biotic components that sum to create the world around us. Ecology –The study of how organisms interact with one another and with their nonliving environment.

Who are? Environmental Scientists –Scientists from biological, physical, chemical and social sciences who study how the earth works, how we interact with the earth, and how to solve environmental problems. Ecologists –Scientists who study the relationship between living organisms and their environment. Environmentalists - Not necessarily scientists!

is the amount of productive land and water needed to support a nation’s resource needs. Translates to the Environmental Impact of each person on the planet. NOTE!! The ecological capacity of the world may already be smaller than its ecological footprint. Ecological Footprint

Fig. 1-8 p million people using 15 times the country’s true area Would need 3 Earths for the Earth’s population of 6 billion people to use the resources we do in the US.

Resources Ecological Resources –Anything an organism needs for normal maintenance, growth and reproduction. Examples: habitat, food, water, and shelter Economic Resources –Anything obtained from the environment to meet human needs and wants Examples: food, water, shelter, manufactured goods, transportation, communication, and recreation.

Resource Types Renewable Resources –Can be replenished in the short term (hours- years) through natural processes only at a rate at which nature provides them Examples: solar, forests, grasslands, wild animals, fresh water, fresh air, and fertile soil

Resource Types Nonrenewable Resource –are those that exist in fixed quantity in the earth’s crust. –Examples: Energy resources - oil, coal, natural gas Metallic mineral resources - copper, iron, aluminum Nonmetallic minerals - salt, clay, sand, phosphates

When are resources depleted? Renewable Resources –Will be depleted when they are used at a higher rate than they can be replenished. Sustainable Yield –Is the highest rate at which a renewable resource can be used indefinitely w/o reducing its available supply

Environmental Degradation Occurs when a resource’s natural replacement rate is exceeded by our amount of use. –Examples Urbanization of productive lands Soil erosion Deforestation Overgrazing of livestock Reduction of biodiversity Pollution –“Tragedy of the Commons”

What is Pollution? Any substance that threatens the health, survival, and activity of living organisms. –Air, Water, Soil, Food Where does Pollution come from? –Point Sources - Easily identified –Nonpoint Sources - Dispersed

IPAT Model – See web site for more info I = P A T Environmental Impact Number of people Affluence per person Environmental effect of technologies