UNIT 1: CHAPTER 1SCIENCE AND THE ENVIRONMENT

Section 1: Understanding our Environment Environmental science studies the impact of humans on the environment.

goals: understanding and solving environmental problems

2 focus areas: (1) how we use natural resources and (2) how our actions alter our environment

branches/fields of study (w/i env. science): ecology, geology, chemistry, botany, zoology, paleontology, social sciences...INTERDISCIPLINARY!

ENVIRONMENT...A LOOK THROUGH TIME

Hunter-Gatherers:

fires, overhunting…strategies!

Led to: Agriculture (collecting seeds—artificial selection, domesticating animals); began ~10,000 years ago in various parts of the world.

Dramatic impact on societies and the environment…called the agricultural revolution.

Lasting Effects

• Due to the replacement of forests, grasslands, and wetlands with farmlands, long-lasting effects resulted:

• Habitats were lost

• Soil loss (due to replacement of forests with farms)

• Floods (due to replacement of forests with farms)

• Water shortages (due to irrigation)

• Infertile soil (due to overfarming)

Next…Industrial Revolution

• Up until the mid 1700s, societies were powered primarily by the work of humans or animals—then began the switch to fossil fuels (coal and oil).

• Result: increased efficiency and productivity of agriculture, industry, and transportation

• Less land needed for agriculture—fewer people grew their own food and urban populations increased

• Positive changes in quality of life: invention of the light bulb, telephone and the portable computer; sanitation, nutrition and medical care improved

• Negatives: replacement of natural animal and plant products with artificial substances (ex. plastics, pesticides); most of environmental science is concerned with the problems associated with the IR.

Earth’s Problems?

• Earth is a closed system: only energy from the sun can enter and only heat energy can leave.

• b/c some resources are limited, as the population grows, resources will be used

• more wastes are produced more quickly than we can dispose of them (i.e. pollution)

• Different scales of env. problems: local (property owners dispute about land use or pest problem), regional (polluted drinking water), or global (ozone depletion)

3 Main Environmental Problems

1. Resource depletion: occurs when a large fraction of natural resources has been used up (renewable vs. nonrenewable)

2. Pollution: an undesired change in air, water, or soil that negatively affects the health, survival, or activities of humans OR other organisms (biodegradable vs. non-degradable)

3. Loss of biodiversity: extinction, species are considered to be a non-renewable resource

• Biodiversity: the number and variety of species in a given area.

Section 2:The Environment and

Society• “The Tragedy of the Commons” by ecologist

Garrett Hardin published in 1968

• The problem in solving environmental issues is the conflict that results from short-term interests and long-term interests

• Someone/group has to take responsibility for mainatining a resource---otherwise the resource(s) can become overused and then depleted.

• Long-term solutions and improvements have to take precedence

Economics and the Environment

• Factors that influence how we use resources:

• Social Pressures

• Supply and Demand (ex. production of oil and price…choices: increase price, decrease use, find new sources of energy)

• Costs and Benefits

• risk assessment—important that the risk is perceived accurately

Developed vs. Developing

• Developed: countries having higher avg. incomes, slower population growth, diverse industrial economies, and stronger social support systems (UN)

• US, Canada, Japan, and the countries of Western Europe

• Use about 75% of the world’s resources but only make up about 20% of the world’s population! Why?...support quality of life

• Developing: countries having lower avg. incomes, simple and agriculture-based economies, and rapid population growth (UN)

• Haiti, India, Chile, Mexico, Libya, Thailand

• ~5.2 billion people live in developing countries; fewer than ½ have access to enough food, safe drinking water, and proper sanitation. Result: malnutrition, starvation, disease, soil infertility, animal extinction.