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AN INTRODUCTION TO ENVIRONMENTAL SCIENCE Dr. B. K. Bindhani Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Assistant Professor KIIT School of Biotechnology KIIT University, Bhubaneswar, Orissa, India This lecture will help you understand: • The nature of environmental science. • The scientific method and the scientific process. • Natural resources and their importance. • Culture worldviews. and • Environmental ethics. • Sustainability. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings The “environment” Consists of both: Biotic factors (living things) & Abiotic factors (nonliving things) that surround us and with which we interact. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Humans and the environment • We humans exist within the environment and are a part of the natural world. • Like all other species, we depend for our survival on a properly functioning planet. • Thus, our interactions with our environment matter a great deal. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Natural resources • Renewable resources like sunlight cannot be depleted. • Nonrenewable resources like oil CAN be depleted. • Resources like timber and clean water are renewable only if we do not overuse them. Figure 1.1 Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Global human population growth • Our population has skyrocketed to over 6 billion. • The agricultural and industrial revolutions drove population growth. Figure 1.2 Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Thomas Malthus (1766-1834) Population growth will lead to starvation, war, disease. Death rates check population unless birth rates are lowered. In our day, Paul Ehrlich (The Population Bomb, 1968) is called “neo-Malthusian.” Figure 1.3 Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings “The tragedy of the commons!” Garrett Hardin, 1968: In a “commons” open to all, unregulated use will deplete limited resources. Figure 1.4 Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Environmental science How does the natural world work? How does our environment affect us? How do we affect our environment? Applied goal: Developing solutions to environmental problems. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings What is an “environmental problem?” Definitions differ. The pesticide DDT: was thought safe in 1945 is known to be toxic today but is used widely in Africa to combat malaria Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.5 Environmental science … can help us avoid mistakes made by past civilizations. On Easter Island, people annihilated their culture by destroying their environment. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings From The Science behind the Stories Environmental science … is an interdisciplinary field, drawing on many diverse disciplines. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Figure 1.6 Environmental science … is NOT the same as environmentalism. It is science, NOT advocacy. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Science A systematic process for learning about the world and testing our understanding of it A dynamic process of observation, testing, and discovery And the accumulated body of knowledge that results from this process Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Applications of science Policy decisions and management practices are applications of science. Prescribed burning, used to restore forest ecosystems altered by human suppression of fire. Figure 1.8a Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Applications of science Technology is another application of science. Energy-efficient methanol-powered fuel cell car from DaimlerChrysler Figure 1.8b Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Scientific method: Assumptions Fixed natural laws govern how the universe works All events arise from causes, and cause other events We can use our senses and reason to detect and describe nature’s laws Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Scientific method A step-by-step method for testing ideas with observations. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Scientific method Scientists use educated guesses called hypotheses to generate predictions that are then tested experimentally. Results may reject or fail to reject a hypothesis. Results never confirm a hypothesis, but only lend support to it by failing to reject it. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Experiments Manipulative experiments are strongest. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Natural or correlational ones are often necessary. Figure 1.10 Scientific process Peer review, publication, and debate are parts of the larger scientific process. Figue 1.11 Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Hypothesis, theory, and paradigm Hypothesis = an educated guess, to be tested Theory = a well-tested and widely accepted explanation, validated by much previous research Paradigm = a dominant view. May shift if new results show old results or assumptions to be wrong Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Ethics Ethics is a discipline that deals with how we value and perceive our environment. Ethics influence our decisions and actions. Figure 2.1 Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Worldview Worldview = a person’s or group’s beliefs about the meaning, purpose, operation, and essence of the world. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Some questions in environmental ethics Should the present generation conserve resources for future generations? Is it OK to destroy a forest to create jobs for people? Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Are humans justified in driving other species to extinction? Is it OK for some communities to be exposed to more pollution than others? Three ethical worldviews Ecocentric: Denote a nature-centred, as opposed to human-centred, system of values. Biocentric: The value of non-human life in nature Anthropocentric: Humans as the central element of the universe. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Early environmental philosophers The industrial revolution inspired reaction. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings The preservation ethic John Muir (right, with President Roosevelt at Yosemite) advocated preserving unspoiled nature, for its own sake and for human fulfillment. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings The conservation ethic Gifford Pinchot advocated using natural resources, but exploiting them wisely, for the greatest good for the greatest number for the longest time. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings The land ethic Aldo Leopold urged people to view themselves as part of nature, and to strive to maintain “the integrity, stability, and beauty of the biotic community.” Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Environmental justice (EJ) Poor people and minorities suffer more than their share of environmental problems, EJ advocates say. The EJ movement began with a protest against a toxic waste dump in an African-American community in North Carolina. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Sustainability The key concept for our future: Limiting human impact on the natural world so that our civilization can continue to exist. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Sustainable development UN: Development that “meets the needs of the present without sacrificing the ability of future generations to meet theirs”. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Conclusions: Challenges We live on a planetary island with limited resources. Population and consumption are growing. Many feel that we have not yet developed the ethical basis for sustainability. Environmental justice remains a challenge. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Conclusions: Solutions We are developing ideas and technologies to lessen our impacts. We can reduce consumption. population and Sustainability is catching on. Science helps us understand our world and develop solutions. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Conclusions: Solutions Environmental science is vibrant and growing. Ethics evolve, and we may yet develop an ethical basis for sustainability. Advances in technology and efficiency can mitigate our environmental impacts. Advances have been made toward environmental justice. Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings