Chapter 1 Science & the Environment

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1 Sec 1 Understanding Our Environment Objectives Define environmental science and compare environmental science with ecology List the 5 major fields of study that contribute to environmental science Describe the major environmental effects of hunter-gathers, the agricultural revolution, and the industrial revolution Distinguish between renewable and nonrenewable resources Classify environmental problems into three major categories What makes up the environment? The environment includes EVERYTHING around us. The natural world Those things produced by More importantly, the environment is a that connects us with the world we live in. What is Environmental Science? Major goal: Environmental science is the study of the. To understand and solve environmental problems To accomplish this goal: Two main types of human/environment interaction must be studied How do we study the environment? How we use our How our Environmental science is an interdisciplinary science Five major fields of study: Biology study of Earth Science study of the earth s nonliving things and the planet as a whole Physics study of 1

2 Chemistry study of chemicals and their interactions Social Sciences study of human populations Eco-Fact The Fall of Troy Environmental problems are nothing new. Nearly 3000 years ago, the Greek poet Homer wrote about the ancient seaport of Troy, which was located beneath a wooded hillside. The Trojans cut down all the trees on the surrounding hills. Without trees to hold the soil in place, rain washed the soil into the harbor. So much silt accumulated in the harbor that large ships could not enter and Troy s economy collapsed. Today, the ruins of Troy are several miles from the sea. Our Environment Through Time Wherever humans have hunted, grown food, or settled, they have Figure 4 Page 9: Three hundred years ago, Manhattan was a very different place. The painting shows an area where Native Americans hunted and fished. Hunters-Gatherers For most of human history, people were hunter-gatherers Early hunter gatherer groups were small, and they migrated from place to place as different types of foods became available at different times of the year. Hunter-Gatherer How did the hunter-gatherers affect their environment? Agricultural Revolution The tribes set fires to burn the prairies and prevent the In a search for food, hunter-gatherers overhunted several species to extinction including: Giant sloths Mastodons What is agriculture? Saber-toothed cats is the practice of growing, breeding, and caring for plants and animals that are used for food, clothing, housing, transportation, and other purposes. 2

3 Agricultural Revolution This practice started in many different parts of the world over. This dramatic change is known as the. The agricultural revolution allowed: Agricultural Revolution to grow at an unprecedented rate An area of land to support up to 500 as many people by farming as it can by hunting and gathering Populations to concentrate in Increased pressure on Other changes from the agricultural revolution: Industrial Revolution The food we eat Wild plants Habitats were Grasslands, forests, and wetlands were replaced with farmland This caused soil loss, floods, and In the middle 1700s, a shift from energy sources, such as animal muscle and running water to fossil fuels, such as oil and coal, occurred The increased use of, such as steam engines, changes society and greatly increased the efficiency of agriculture, industry, and transportation Industrial Revolution The industrial revolution: Industrial Revolution Large scale production of goods became Machinery reduced the amount of land and Fewer people grew their own food Populations in urban areas steadily grew allowed food and other goods to be transported cheaply across great distances 3

4 Positive Changes: Industrial Revolution Inventions, such as the light bulb, greatly improved our Agricultural productivity Sanitation, nutrition, and medical care vastly enabled people to work and communicate more easily from any location Environmental Problems: Spaceship Earth Use of in place of raw animal and plant products Plastics and other artificial materials make life, but present many environmental problems. caused by burning of fossil fuels Earth is essentially a The only thing that enters is energy from the sun and the only thing that leaves is heat We are unable to dispose of waste or take on new supplies Potential Problems: Spaceship Earth Limited As populations grow, resources become Wastes are produced more quickly that we can dispose of them Environmental problems can occur on different scales: Local Global Population Growth: A Local Pressure Human population almost quadrupled during the In the past 50 yrs, nations have used vast amounts of resources to meet their needs 4

5 What Are Our Main Environmental Problems? Resource Depletion Pollution Loss of Biodiversity Resource Depletion Natural resource Two classifications: Resource Depletion a source that can be replaced relatively quickly by natural processes Fresh water, air soil, trees, and crops Energy from the sun a resource that forms at a much slower rate than the rate that it is consumed Minerals Fossil fuels Resources are said to be when a large fraction of the resource has been used up. Pollution Nonrenewable: Copper in a copper mine Renewable: trees harvested at a much faster rate than they can grow naturally in an area ( ) One major effect of the Industrial Revolution: Pollution: an undesired change in air, water, or soil that adversely affects the health, survival, or activities of humans or other organisms. Human activities produce a great deal of pollution. Pollution Two main types of pollutants: Pollutants that can be broken down by 5

6 Loss of Biodiversity Materials such as human sewage and food wastes Problem when they accumulate faster than they can degrade Pollutants that cannot be broken down by natural processes can reach dangerous levels Materials such as mercury, lead, and Biodiversity: the of species that live in an area. Earth has been home to hundreds of millions of species; yet, only a fraction of those species are alive today Loss of Biodiversity : a natural process where no members of a specific species exists The organisms that share the world with us can be considered a A species that is can be considered a resource We depend on other organisms for such things as: 6

7 Sec 2 The Environment and Society Objectives Describe The Tragedy of the Commons Explain the law of supply and demand List three differences between developed and developing countries Explain what sustainability is, and describe why it is a goal of environmental science Who owns the Ocean? The open ocean is Yet, people from many countries use the ocean for fishing and for transporting goods. How do we decide how to share common resources? In 1968, ecologist Garrett Hardin published an essay titled, which addressed this question. The Tragedy of the Commons Hardin argued that the main difficulty in solving environmental problems is the conflict between the. Hardin used the example of the commons The Tragedy of the Commons Commons: areas of land that belonged to. Anyone could graze their animals on the commons. Individual : graze as many animals as possible (If I don t use this resource, someone else will) : overgrazing led to the destruction of land resources everyone suffered, no one could raise animals) The Tragedy of the Commons When commons were replaced by closed fields owned by individuals, owners were careful their land. What is the point?: Someone or some group has to take responsibilty for maintaining a resource. If no one takes that responsibility, the resource can be. 7

8 What are our Commons? Earth s natural resources are our. We can solve environmental problems by: The solution may override short term interests, but improves the environment in the long term. Economics and the Environment Economic forces influence how we use resources: Supply and Demand Supply and Demand Costs and Benefits Risk Assessment Law of Supply and Demand: the greater the demand for a limited supply of something, the more that thing is worth Costs and Benefits Oil Production If the supply of oil decreases, we have three choices: Cost-Benefit Analysis: The results of a CBA often depend on who is doing the analysis. To an industry: the cost of pollution may outweigh the benefits To a nearby community: the benefits may be worth the high price The cost of is often passed on to the consumer of the taxpayer. 8

9 Risk Assessment Cost-benefit analysis involves risk assessment: To come up with an effective solution to an environmental problem, the public must perceive the risk accurately. Nuclear power vs riding a bicycle (pg. 17) Developed and Developing Countries Developed and developing countries have different consumption patterns which affect the environment in different ways. The unequal distribution of wealth and resources around the world influences environmental The United Nations classifies countries as: Developed Nations Examples: United States, Canada, Japan, and those of Western Europe Developing Nations Examples: Ethiopia and other poor countries in Africa, Central America, and South America Population and Consumption Most environmental problems can be traced back to two root causes: The human population in some areas is for the local environment to support it People are resources faster than they can be replaced or cleaned up 9

10 Local Population Pressures When the population in an area grows rapidly, there may not be enough natural resources for everyone in that area to. What are the consequences? Consumption Trends The environment suffers Food production, education, and Developed nations use about, even though they make up only about. Indicators of Development (TABLE) Ecological Footprint Ecological Footprint: productive area of Earth needed to support one person in a particular country. It estimates: Ecological Footprint (acres) per Country Thinking Critically Learning to think critically about what you see in newspapers, on TV, and on the Internet will help you make informed decisions. Remember: Try to understand that people have many reasons for the opinions they form be careful how you react If you want your opinions to be heard, make sure to listen to others as well Investigate the source of the information you encounter 10

11 A Sustainable World Gather all the info you can before drawing a conclusion. Sustainability: A sustainable world is not an unchanging world At the present time, our world is far from sustainable. Did you know??? We are using our resources much faster than they can be replenished. If the environment on Earth changed drastically, would we have anywhere to go? There are no other planets in our solar system with an adequate range of temperatures, a breathable atmosphere, or the resources needed to sustain humans with our present technology. There may be other planets like Earth in the universe, but the closest planets we know of are in other solar systems that are light-years away. 11