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Lecture Environmental science - Chapter 1: Introduction - toward a sustainable future

In this chapter, you will learn: Understand how natural world works, understand how human systems interact with natural system, accurately determine environmental problems, develop and follow a sustainable relationship with natural world. | Chapter 1: Introduction Toward a Sustainable Future Rachel Carson was a scientist who wrote Silent Spring in 1962. It addressed the growing use of pesticides (DDT) and their unpredicted effects on song birds. Original users of pesticides did not know that the poisons used to kill insects would accumulate in other living things and kill them too. BIOACCUMULATION Themes Sustainability: A process can continue indefinitely without depleting resources used *no sacrifice to future generations* Stewardship: Caring for something that does not belong to you Science: Use the scientific method and question authority Ecosystem Capital: Essential goods and services like food, water, and fuel Policy and Politics: Human decisions determine what happens to the natural world Globalization: The interconnectedness of human activities, ideas, and cultures Environmental Science Understand how natural world works Understand how human systems interact with natural system Accurately determine environmental problems Develop and follow a sustainable relationship with natural world Lessons from a Small Island Easter Island (Rapa Nui) http://www.netaxs.com/~trance/rapa.ram Easter Island Home Page and Music http://www.netaxs.com/~trance/rapanui.html Map of Easter Island Area - 166 km2 In the 4th century A.D there were approximately 10,000 people living here Use of resources Natural Resources Fresh water Trees Fish Brought by settlers Chickens Sweet potatoes Taro Yams Used for: Building houses Food Clothing Technology Stone statues (moai) Needed many trees to move the statues Moai There are 887 moai on Easter Island Average Height: 13.29 feet (4.05 meters) some are more than 20 feet (6 meters) Average weight: 13.78 tons Dutch explorers arrive in 1772 600 people left Constant war Few of the natural resources left What happened! 4 Global trends: Population growth and economic development Soil Degradation Global atmospheric changes Loss of biodiversity A. Human population growth More than 6.6 billion people currently (2007) We are adding 76 million people per year increase pop → increase need for resources Note: This graph is from 1999. These predictions are based on a faster growth rate. Carrying capacity is higher in this graph. LOOK at Fig. 1-3, pg 5!!! Different lifestyles have different demands on the environment Developed (industrialized) countries like America hot running water more than one car per family -VS- Developing countries like Tanzania hunting/gathering Firewood for heat and cooking 1 billion + people live in poverty B. Soil degradation Demand for food destroys the soil erosion minerals in soil are depleted salinization increased use of pesticides overuse of fresh water C. Global Atmospheric Changes Global Warming CO2 produced from fossil fuel burning acts like a blanket around the earth. Plants take CO2 out of the atmosphere through photosynthesis 6CO2 +6H2O => 602 + C6H12O6 Ozone depletion Chemicals released from the surface of the earth destroy our ozone shield. No stratospheric ozone, no protection from the UV rays of the sun. D. Loss of Biodiversity Habitat destruction leads to a loss of many species starting with the plants exact # of species lost is unknown because not all species are identified strong ecosystems need biodiversity 1959-1980 25% of all prescription drugs from natural resources Wild species keep domestic species vigorous Aesthetics A sustainable future is possible Nutrition levels and life expectancy are rising Population growth rates are falling It is cool to be “green” YOU are taking this class Lessons from a Small Island Easter Island (Rapa Nui) http://www.netaxs.com/~trance/rapa.ram http://www.netaxs.com/~trance/rapanui.html