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!
Ecological Footprint • 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 • 16 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. Fig. 1-8 p. 10
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
Environmental Impact Affluence per person I = P A T Environmental effect of technologies Number of people IPAT Model – See web site for more info