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Download Ch. 1 Introduction to Environmental Science
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Chapter 1 Understanding the Environment Chapter 1, Section 1 What is an environment? Class discussion: What do you think of when you hear the word environment? Did anyone think of the environment in their own backyard? What is the environment? The environment is not only the landscape and animals that you can see, it is also how they interact Environmental Science Definition: The study of how humans interact with the environment Involves the following interactions between human and the environment: How humans use natural resources How human beings relate to the nonliving environment How human actions alter the environment (All of the above) Environmental Science What is studied in environmental science? Interactions between living organisms and their nonliving environment Impact of humans on the environment Interaction between organisms (All of the above) The Goals of Environmental Science To understand and solve environmental problems Do this in two ways: Study how humans use natural resources Study how our actions alter the environment Environmental Science Studies Many Fields of Science Ecology – The study of how living things interact with each other and with their nonliving environment Fields Continued Biology – the study of living organisms Zoology – the study of animals Botany – the study of plants Microbiology – the study of microorganisms Ecology - the study of the home Fields Continued Earth Science – the study of the Earth’s nonliving systems and the planet as a whole Geology – the study of the Earth’s surface, interior processes, and history Paleontology – the study of fossils and ancient life Climatology – the study of the Earth’s atmosphere and climate Hydrology – the study of the Earth’s water resources Fields Continued Physics – the study of matter and energy Engineering – the science by which matter and energy are made useful to humans in structures, machines, and products Fields Continued Chemistry – the study of chemicals and their interactions Biochemistry – the study of the chemistry of living things Geochemistry – a branch of geology, is the study of the chemistry of materials such as rocks, soil, and waste Fields Continued Social Science – the study of human population Geography – the study of the relationships between human populations and Earth’s features Anthropology – the study of the interactions of the biological, cultural, geographical, and historical aspects of humankind Sociology – the study of human population dynamics and statistics NOT linguistics and physics (d) Scientists as Citizens, Citizens as Scientists Environmental Science starts with the non-scientists What would you do if you came across a creature that looked like this? Our Environment Through Time Humans changed environment over time through: Hunting Agriculture When they settled Hunter-Gatherers For most of history, people were hunter gatherers They obtained food through: Collecting plants Hunting wild animals Scavenging their remains Humans lived in tribes, using fires to maintain the prairie They would migrate as groups throughout the year to where resources were bountiful Would you be willing to move every month to obtain food? Early Environmental Problems Native American tribes and Aborigines would burn down forests and grasslands to drive out animals such as Buffalo They would carry plants with them where they traveled – invasive exotic species Endangered Species Led to extinction of mammals such as: Giant bison Mastodons Cave Bears Saber-Toothed Cats Would trap in pits and then kill them The Agricultural Revolution Agriculture – the practice of growing, breeding, an caring for plants and animals that are used for food, clothing, housing, transportation, and other purposes. It happened 10,000 years ago It had such an impact on humans that it became a revolution Plants and animals were domesticated, human populations grew One area of land could now support up to 500 times the amount of people that could be supported by hunting and gathering Communities began to grow Population growth in the 20th century led to Resource depletion Habitat destruction Pollution (all of the above) This agriculture changed the foods that we eat today We eat descendents of the plants first found by hunters and gatherers Over time, they picked desired traits in plants and began to only harvest those desired traits As environments were replaced by agriculture, they were destroyed Slash-and-burn – cut down and burn old environments to plant crops – currently ocurring in rainforest Industrial Revolution Occurred in the middle of the 1700’s Involved a shift from energy resources such as animal muscle and running water to fossil fuels Allowed for machinery to take over in mass producing goods and agriculture People began to travel more and move to cities Society shifted to fossil fuels When most of today’s environmental problems began answer C Improving Quality of Life Brought us things such as the light bulb and mass agriculture Also brought us pollution and habitat loss Included the start of artificial substances in place of raw animal and plant products Plastics, artificial pesticides and fertilizers, etc. These products made our life easier, but what about the rest of the environment? Spaceship Earth Earth is a closed system It is like a spaceship travelling through space that cannot dispose of waste or take on new supplies Problems occur on different scales: Local Regional Global Population Growth: A Local Pressure Our population is growing faster than our resources can support The Agricultural and Industrial Revolutions gave us power to grow much faster than before Are we growing to fast? What are the main environmental problems? Resource Depletion Pollution Loss of Biodiversity Resource Depletion Natural Resource – Any natural material that is used by humans Either renewable or nonrenewable Renewable resources can be replaced quickly by natural processes Nonrenewable resources - natural material formed at a slower rate than it is depleted Resource Depletion - rate of resource use depletes resources and creates pollution and wastes Depleted Resource When a large fraction of the resource has been used up Pollution Pollution – an undesired change in air, water, or soil Two types of pollutions Biodegradable – pollutants that can be broken down by natural processes Nondegradable – those that can’t – plastics, mercury, lead, etc. Loss of Biodiversity Biodiversity – the number of variety of species that live in an area Extinction – a natural process Mass Extinction – several extinctions happening at the same time The loss of the worlds biodiversity is a concern because: Humans depend on other organisms for food and oxygen The Environment and Society Chapter 1, Section 2 The Tragedy of the Commons Garrett Hardin – 1968 Describes conflicts associated with sharing resources Commons are patches of grassland If everyone lets too many sheep on the grasslands, they will destroy the environment If people divide the commons and maintain the sheep population, the environment will survive We need to do the same with our environment The Law of Supply and Demand The law of supply and demand describes: Reduced demand resulting from lack of available resources Market Equilibrium Market Equilibrium - Listing both the merits and expenses involved in implementing a particular environmental solution Economics and the Environment Supply and Demand – the greater the demand for a limited supply of something, the more that thing is worth Cost and Benefits – This balances the cost of the action against the benefits one expects from it (is an environmental action worth it?) Risk Assessment – A tool that helps us create costeffective ways to protect our health and the environment Developed and Developing Countries Developed Countries – characterized by high personal wealth, and high levels of consumption Typically have a larger ecological footprint Developing Countries – characterized by high population growth rate, extreme poverty Population and Consumption Local Population Pressures Consumption Trends Ecological Footprints Local Population Pressures Often, populations increase in developing nations It increases faster than resources can be provided Of the 4.5 billion people in developing countries, fewer than half have access to enough food, safe drinking water, and proper sanitation Consumption Trends Population control, pollution depletion, and resource abundance has improved in the wealthier part of the world This is only done by hogging the resources from developing countries that need them as well Ecological Footprint An ecological footprint shows the productive area of Earth needed to support one person in a particular country Environmental Science in Context Environmental problems are large Simple answers are rare Critical thinking and the Environment Environmental Information is often construed by political pull or for sales How to approach it: 1. Be prepared to listen to many viewpoints Understand their reasoning before reacting to their ideas If you want your opinion to be heard, you must also be willing to listen to others 2. Investigate the source of any information you encounter A Sustainable World The key goal of environmental science is to achieve sustainability Sustainability – the condition in which human needs are met in such a way that a human population can survive indefinitely This goal requires everyone’s participation The 21st Century is a critical time in finding sustainability What will you do to make a change?
