Presentation on theme: "SCIENCE AND THE ENVIRONMENT"— Presentation transcript:
1 SCIENCE AND THE ENVIRONMENT UNIT 1: CHAPTER 1SCIENCE AND THE ENVIRONMENT
2 Section 1: Understanding our Environment Environmental science studies the impact of humans on the environment.goals: understanding and solving environmental problems2 focus areas: (1) how we use natural resources and (2) how our actions alter our environmentbranches/fields of study (w/i env. science): ecology, geology, chemistry, botany, zoology, paleontology, social sciences...INTERDISCIPLINARY!
3 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.
4 Lasting EffectsDue to the replacement of forests, grasslands, and wetlands with farmlands, long-lasting effects resulted:Habitats were lostSoil 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)
5 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 transportationLess land needed for agriculture—fewer people grew their own food and urban populations increasedPositive changes in quality of life: invention of the light bulb, telephone and the portable computer; sanitation, nutrition and medical care improvedNegatives: 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.
6 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 usedmore 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)
7 3 Main Environmental Problems Resource depletion: occurs when a large fraction of natural resources has been used up (renewable vs. nonrenewable)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)Loss of biodiversity: extinction, species are considered to be a non-renewable resourceBiodiversity: the number and variety of species in a given area.
8 Section 2: The Environment and Society “The Tragedy of the Commons” by ecologist Garrett Hardin published in 1968The problem in solving environmental issues is the conflict that results from short-term interests and long-term interestsSomeone/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
9 Economics and the Environment Factors that influence how we use resources:Social PressuresSupply and Demand (ex. production of oil and price…choices: increase price, decrease use, find new sources of energy)Costs and Benefitsrisk assessment—important that the risk is perceived accurately
10 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 EuropeUse about 75% of the world’s resources but only make up about 20% of the world’s population! Why?...support quality of lifeDeveloping: 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.