Introduction to Environmental Science Sp16
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Introduction to EnvironmentalScienceRobert StewartJessica BerrymanSay Thanks to the AuthorsClick http://www.ck12.org/saythanks(No sign in required)
To access a customizable version of this book, as well as otherinteractive content, visitwww.ck12.orgCK-12 Foundation is a non-profit organization with a mission toreduce the cost of textbook materials for the K-12 market both inthe U.S. and worldwide. Using an open-source, collaborative, andweb-based compilation model, CK-12 pioneers and promotes thecreation and distribution of high-quality, adaptive online textbooksthat can be mixed, modified and printed (i.e., the FlexBook®textbooks).Copyright © 2017 CK-12 Foundation, www.ck12.orgThe names “CK-12” and “CK12” and associated logos and theterms “FlexBook®” and “FlexBook Platform®” (collectively“CK-12 Marks”) are trademarks and service marks of CK-12Foundation and are protected by federal, state, and internationallaws.Any form of reproduction of this book in any format or medium,in whole or in sections must include the referral attribution linkhttp://www.ck12.org/saythanks(placed in a visible location) inaddition to the following terms.Except as otherwise noted, all CK-12 Content (including CK-12Curriculum Material) is made available to Users in accordancewith the Creative Commons Attribution-Non-Commercial 3.0Unported (CC BY-NC 3.0) License (http://creativecommons.org/licenses/by-nc/3.0/), as amended and updated by Creative Com-mons from time to time (the “CC License”), which is incorporatedherein by this reference.Complete terms can be found athttp://www.ck12.org/about/terms-of-use.Printed: January 8, 2017AUTHORSRobert StewartJessica BerrymanEDITORMichelle Rogers-Estable
www.ck12.orgChapter 1.Introduction to Environmental ScienceCHAPTER1Introduction toEnvironmental ScienceCHAPTEROUTLINE1.1Course Introduction1.2Science and the Natural World1.3Biology: The Study of Life1.4What does it mean to be sustainable?1.5Environmental Issues Today1.6Looking Ahead with Hope1.7References1
1.1. Course Introductionwww.ck12.org1.1Course IntroductionEnvironmental Science is the study of theclimatic, physical, chemical, biological, and human interactions thattransform and transport materials and energy.Humans rely upon on these interactions for survival and life.Because this is a Life Science course, we will focus on the underlying biological principles that are involved inevery environmental issue. This course will guide you through the underlying biological principles that have allowedecosystems on Earth to arise and persist and will help you to have the foundational knowledge necessary to makeinformed decision about environmental issues.In particular, this course will focus on the issue of sustainable food systems.As you go through each chapter,you will learn some background information that will better enable you to critically think about how to promotesustainable food systems.Chapter Objectives• Define Biology.• List the steps of the Scientific Method.• Describe the Characteristics of Life.• Understand the Hierarchy of Life.• List the 6 Kingdoms.• Describe what is Environmental Science.• Discuss four major environmental issues today• Define sustainable and describe the three dimensions of sustainability.• Describe the Tragedy of the Commons and give examples of how it impacts environmental resources.2
www.ck12.orgChapter 1.Introduction to Environmental Science1.2Science and the Natural WorldLesson Objectives• Identify the goal of science.• Describe how scientists study the natural world.• Explain how and why scientists do experiments.• Describe types of scientific investigations.• Explain what a scientific theory is.Vocabulary• evidence• hypothesis• observation• prediction• science• scientific investigation• scientific law• scientific method• scientific theoryIntroductionDid you ever wonder why giraffes have such long necks or how birds learn to sing their special songs? If you everasked questions such as these about the natural world, then you were thinking like a scientist. The wordsciencecomes from a Latin word that means “knowledge.”Scienceis a distinctive way of gaining knowledge about thenatural world that starts with a question and then tries to answer the question with evidence and logic. Science is anexciting exploration of all the whys and hows that any curious person might have about the world. You can be partof that exploration. Besides your curiosity, all you need is a basic understanding of how scientists think and howscience is done, starting with the goal of science.The Goal of ScienceThe goal of science is to understand the natural world. To achieve this goal, scientists make certain assumptions.They assume that:• Nature can be understood through systematic study• Science is based on observations using our physical senses.• Scientific results are repeatable and verifiable by anyone.• Scientific ideas are open to revision and self correcting.• Sound scientific ideas withstand the test of time.• Science cannot provide answers to all questions.3
1.2. Science and the Natural Worldwww.ck12.orgNature Can Be UnderstoodScientists think of nature as a single system controlled by natural laws. By discovering natural laws, scientists striveto increase their understanding of the natural world. Laws of nature are expressed as scientific laws. Ascientificlawis a statement that describes what always happens under certain conditions in nature.An example of a scientific law is the law of gravity, which was discovered by Sir Isaac Newton (seeFigure1.1). Thelaw of gravity states that objects always fall towards Earth because of the pull of gravity. Based on this law, Newtoncould explain many natural events. He could explain not only why objects such as apples always fall to the ground,but he could also explain why the moon orbits Earth. Isaac Newton discovered laws of motion as well as the law ofgravity. His laws of motion allowed him to explain why objects move as they do.FIGURE 1.1Did Newton discover the law of gravity when an apple fell from a tree andhit him on the head? Probably not, but observations of nature are oftenthe starting point for new ideas about the natural world.Science Is Based On ObservationsAnything subjected or analyzed using the scientific method must be based on observations using one of our 5 senses.Much scientific advancement has come through technology to enhance our senses.As technology continues toincrease, our understanding of the natural world will increase as well.Certain questions can not yet be addressedscientifically because we currently lack the technology to study them. So, those questions are outside of the realmof science. If you can not reliably see it, touch it, taste it, hear it, or smell it, it is not testable. It does not mean thatthose questions are not important. I simply means that another method of inquiry must be used for now.Scientific Results Are Repeatable And VerifiableFurthermore, scientific observations need to be repeatable. One should be able to make the same observations againand again and be verifiable by anyone else.This is essential because of the next 2 assumptions.If you and otherscan not reliably make the same observation, your conclusions can not be put through the test of time.Scientific Ideas Can ChangeScience is more of a process than a set body of knowledge. Scientists are always testing and revising their ideas,and as new observations are made, existing ideas may be challenged. Ideas may be replaced with new ideas thatbetter fit the facts, but more often existing ideas are simply revised. For example, when Albert Einstein developedhis theory of relativity, he didn’t throw out Newton’s laws of motion. Instead, he showed that Newton’s laws are apart of a bigger picture. In this way, scientists gradually build an increasingly accurate and detailed understandingof the natural world.4
www.ck12.orgChapter 1.Introduction to Environmental ScienceScientific Knowledge Can Withstand the Test of TimeMany scientific ideas have withstood the test of time. For example, about 200 years ago, the scientist John Daltonproposed atomic theory—the theory that all matter is made of tiny particles called atoms. This theory is still validtoday. There are many other examples of basic science ideas that have been tested repeatedly and found to be true.You will learn about many of them as you study biology.Science Cannot Answer All QuestionsScience rests on evidence and logic, so it deals only with things that can be observed. Anobservationis anythingthat is detected either through human senses or with instruments and measuring devices that extend human senses.Things that cannot be observed or measured by current means—such as supernatural beings or events—are outsidethe bounds of science. Consider these two questions about life on Earth:• Did life on Earth evolve over time?• Was life on Earth created through another method?The first question can be answered by science on the basis of scientific evidence and logic. The second questioncould be a matter of belief. Therefore, it is outside the realm of science.The Scientific MethodThere are basic methods of gaining knowledge that are common to all of science. At the heart of science is thescientific investigation, which is done by following thescientific method. Ascientific investigationis a plan forasking questions and testing possible answers. It generally follows the steps listed inFigure1.2. Seehttp://www.youtube.com/watch?v=KZaCy5Z87FAfor an overview of the scientific method.Once you are familiar with thescientific method, you may enjoy watching a Tedx talk entitled "The Scientific Method is Crap".Making ObservationsA scientific investigation typically begins with observations. You make observations all the time. Let’s say you takea walk in the woods and observe a moth, like the one inFigure1.3, resting on a tree trunk. You notice that the mothhas spots on its wings that look like eyes. You think the eye spots make the moth look like the face of an owl.Asking a QuestionObservations often lead to questions. For example, you might ask yourself why the moth has eye spots that make itlook like an owl’s face. What reason might there be for this observation?Forming a HypothesisThe next step in a scientific investigation is forming a hypothesis. Ahypothesisis a possible answer to a scientificquestion, but it isn’t just any answer. A hypothesis must be based on scientific knowledge, and it must be logical. Ahypothesis also must be falsifiable. In other words, it must be possible to make observations that would disprove thehypothesis if it really is false. Assume you know that some birds eat moths and that owls prey on other birds. Fromthis knowledge, you reason that eye spots scare away birds that might eat the moth. This is your hypothesis.5
1.2. Science and the Natural Worldwww.ck12.orgFIGURE 1.2Steps of a Scientific Investigation.Ascientific investigation typically has thesesteps.FIGURE 1.3Does this moth remind you of an owl?6
www.ck12.orgChapter 1.Introduction to Environmental ScienceTesting the HypothesisTo test a hypothesis, you first need to make a prediction based on the hypothesis. Apredictionis a statement thattells what will happen under certain conditions. It can be expressed in the form: If A occurs, then B will happen.Based on your hypothesis, you might make this prediction: If a moth has eye spots on its wings, then birds will avoideating it.Next, you must gather evidence to test your prediction.Evidenceis any type of data that may either agree or disagreewith a prediction, so it may either support or disprove a hypothesis. Assume that you gather evidence by makingmore observations of moths with eye spots. Perhaps you observe that birds really do avoid eating the moths. Thisevidence agrees with your prediction.Drawing ConclusionsEvidence that agrees with your prediction supports your hypothesis. Does such evidence prove that your hypothesisis true? No; a hypothesis cannot be proven conclusively to be true. This is because you can never examine all ofthe possible evidence, and someday evidence might be found that disproves the hypothesis. Nonetheless, the moreevidence that supports a hypothesis, the more likely the hypothesis will continue to be supported over time.Communicating ResultsThe last step in a scientific investigation is communicating what you have learned with others.This is a veryimportant step because it allows others to test your hypothesis. If other researchers get the same results as yours,they add support to the hypothesis. However, if they get different results, they may disprove the hypothesis.When scientists share their results, they should describe their methods and point out any possible problems withthe investigation. For example, while you were observing moths, perhaps your presence scared birds away. Thisintroduces an error into your investigation. You got the results you predicted (the birds avoided the moths while youwere observing them), but not for the reason you hypothesized. Other researchers might be able to think of ways toavoid this error in future studies.Scientific TheoriesWith repeated testing, some hypotheses may eventually become scientific theories. Ascientific theoryis a broadexplanation for events that is widely accepted as true. To become a theory, a hypothesis must be tested over and overagain, and it must be supported by a great deal of evidence.People commonly use the wordtheoryto describe a guess about how or why something happens. For example, youmight say, “I think a woodchuck dug this hole in the ground, but it’s just a theory.” Using the wordtheoryin thisway is different from the way it is used in science. A scientific theory is more like a fact than a guess because it isso well-supported. There are several well-known theories in biology, including the theory of evolution, cell theory,and germ theory. You will read about all three of these theories in the next lesson “Biology: The Study of Life.” Avideo explaining scientific theories can be seen athttp://www.youtube.com/watch?v=S5YGhprR6KE.7
1.2. Science and the Natural Worldwww.ck12.orgLesson Summary• The goal of science is to understand the natural world through systematic study. Scientific knowledge is basedon evidence and logic.• Scientists gain knowledge through scientific investigations.A scientific investigation is a plan for askingquestions and testing possible answers.• Scientific theories are broad explanations that are widely accepted as true. This is because they are supportedby a great deal of evidence.Lesson Review Questions1. What is science? What is the goal of science?2. Outline the steps of a scientific investigation.3. What is a scientific hypothesis? What characteristics must a hypothesis have to be useful in science?4. Explain why science cannot provide answers to all questions.5. Contrast how the termtheoryis used in science and in everyday language.6. Explain how a hypothesis could become a theory.8
www.ck12.orgChapter 1.Introduction to Environmental Science1.3Biology: The Study of LifeLesson Objectives• List the characteristics of all living things.• State four unifying principles of biology.• Describe how living things interact.• Explain how life on Earth evolves.Vocabulary• adaptation• biodiversity• biology• biome• biosphere• cell• cell theory• community• competition• ecosystem• evolution• gene theory• homeostasis• natural selection• organ• organ system• organism• population• reproduction• symbiosis• tissueIntroductionIn this chapter, you will learn about one particular branch of science, the branch called biology.Biologyis thescience of life. Do you know what life is? Can you define it? Watchhttp://vimeo.com/15407847to begin yourjourney into the study of life.Characteristics of LifeLook at the duck decoy inFigure1.4. It looks very similar to a real duck. Of course, real ducks are living things.What about the decoy duck? It looks like a duck, but it is actually made of wood. The decoy duck doesn’t have allthe characteristics of a living thing. What characteristics set the real ducks apart from the decoy duck? What are thecharacteristics of living things?9
1.3. Biology: The Study of Lifewww.ck12.orgFIGURE 1.4This duck decoy looks like it’s alive. It even fools real ducks. Why isn’t it aliving thing?To be classified as a living thing, an object must have all eight of the following characteristics:1.It responds to the environment and interacts.2.It grows and develops.3.It produces offspring.4.It maintains homeostasis.5.It requires energy and materials.6.It consists of cells.7.It is organized in a hierarchy.8.It evolves.Response to the EnvironmentAll living things depend on their environment to supply them with what they need, including food, water, and shelter.Their environment consists of physical factors—such as soil, air, and temperature—and also of other organisms.Anorganismis an individual living thing. Many living things interact with other organisms in their environment. Infact, they may need other organisms in order to survive. For example, living things that cannot make their own foodmust eat other organisms for food. Other interactions between living things include symbiosis and competition.Symbiosisis a close relationship between organisms of different species in which at least one of the organismsbenefits. The other organism may also benefit, or it may be unaffected or harmed by the relationship.Competitionisa relationship between living things that depend on the same resources.The resources may be food, water, oranything else they both need. Competition occurs whenever they both try to get the same resources in the same placeand at the same time. The two organisms are likely to come into conflict, and the organism with better adaptationsmay win out over the other organism.Growth and DevelopmentAll living things grow and develop. For example, a plant seed may look like a lifeless pebble, but under the rightconditions it will grow and develop into a plant. Animals also grow and develop. Look at the animals inFigure1.5.How will the tadpoles change as they grow and develop into adult frogs?ReproductionAll living things are capable of reproduction.Reproductionis the process by which living things give rise tooffspring. Reproducing may be as simple as a single cell dividing to form two daughter cells. Generally, however,it is much more complicated. Nonetheless, whether a living thing is a huge whale or a microscopic bacterium, it iscapable of reproduction.10
www.ck12.orgChapter 1.Introduction to Environmental ScienceFIGURE 1.5Tadpoles go through many changes tobecome adult frogs.Maintains HomeostasisAll living things are able to maintain a more-or-less constant internal environment. They keep things relatively stableon the inside regardless of the conditions around them. The process of maintaining a stable internal environmentis calledhomeostasis. Human beings, for example, maintain a stable internal body temperature. If you go outsidewhen the air temperature is below freezing, your body doesn’t freeze. Instead, by shivering and other means, itmaintains a stable internal temperature.Energy and MaterialsAll living things—even the simplest life forms—require energy and material resources. Living things consist oflarge, complex molecules, and they also undergo many complicated chemical changes to stay alive. Energy andmaterials are needed to carry out all the functions of life. We will discuss this further when we study photosynthesisand cellular respiration.CellsAll forms of life are built of cells. Acellis the basic unit of the structure and function of living things. Living thingsmay appear very different from one another on the outside, but their cells are very similar. Compare the human cellsand onion cells inFigure1.6. How are they similar? If you click on the animation titledInside a Cellat the linkbelow, you can look inside a cell and see its internal structures.http://bio-alive.com/animations/cell-biology.htmLevels of OrganizationThe living world can be organized into different levels. For example, many individual organisms can be organizedinto the following levels:• Cell: basic unit of all living things•Tissue: group of cells of the same kind•Organ: structure composed of one or more types of tissues11
1.3. Biology: The Study of Lifewww.ck12.orgFIGURE 1.6A representation of human cells (left) and onion cells (right). If you looked at human and onion cells under amicroscope, this is what you might see.•Organ system: group of organs that work together to do a certain job• Organism: individual living thing that may be made up of one or more organ systemsExamples of these levels of organization are shown inFigure1.7.FIGURE 1.7An individual mouse is made up of severalorgan systems. The system shown hereis the digestive system,which breaksdown food to a form that cells can use.One of the organs of the digestive systemis the stomach.The stomach, in turn,consists of different types of tissues. Eachtype of tissue is made up of cells of thesame type.There are also levels of organization above the individual organism. These levels are illustrated inFigure1.8.• Organisms of the same species that live in the same area make up apopulation. For example, all of the12
www.ck12.orgChapter 1.Introduction to Environmental Sciencegoldfish living in the same area make up a goldfish population.• All of the populations that live in the same area make up acommunity. The community that includes thegoldfish population also includes the populations of other fish, coral and other organisms.• Anecosystemconsists of all the living things in a given area, together with the nonliving environment. Thenonliving environment includes water, sunlight, and other physical factors.• A group of similar ecosystems with the same general type of physical environment is called abiome.• Thebiosphereis the part of Earth where all life exists, including all the land, water, and air where livingthings can be found. The biosphere consists of many different biomes.FIGURE 1.8This picture shows the levels of organization in nature, from the individual organism to the biosphere.Evolution of LifeLife on Earth is very diverse. The diversity of living things is calledbiodiversity. A measure of Earth’s biodiversityis the number of different species of organisms that live on Earth. At least 10 million different species live on Earth13
1.3. Biology: The Study of Lifewww.ck12.orgtoday. They are commonly grouped into six different kingdoms. Examples of organisms within each kingdom areshown inFigure1.9.FIGURE 1.9Diversity of life from Archaebacteria toPlants and Animals.The diversity of life on Earth today is the result of evolution. Life began on Earth at least 4 billion years ago, and ithas been evolving ever since. At first, all living things on Earth were simple, single-celled organisms. Much later,the first multicellular organisms evolved, and after that, Earth’s biodiversity greatly increased.Figure1.10showsa timeline of the history of life on Earth. You can also find an interactive timeline of the history of life at the linkbelow.http://www.johnkyrk.com/evolution.htmlToday, scientists accept the evolution of life on Earth as a fact. There is too much evidence supporting evolution todoubt it. However, that wasn’t always the case. An introduction to evolution and natural selection can be viewed athttp://www.youtube.com/watch?v=GcjgWov7mTM. We will discuss evolution further in the next chapter.MEDIAClick image to the left or use the URL below.URL:https://www.ck12.org/flx/render/embeddedobject/156Unifying Principles of BiologyFour unifying principles form the basis of biology.Whether biologists are interested in ancient life, the life ofbacteria, or how humans could live on the moon, they base their overall understanding of biology on these fourprinciples:1. cell theory2. gene theory3. homeostasis4. evolution14
www.ck12.orgChapter 1.Introduction to Environmental ScienceFIGURE 1.10This timeline shows the history of life on Earth.In the entire span of the time, humans are a relatively newaddition.The Cell TheoryAccording to thecell theory, all living things are made up of cells, and living cells always come from other livingcells. In fact, each living thing begins life as a single cell. Some living things, such as bacteria, remain single-celled.Other living things, including plants and animals, grow and develop into many cells. Your own body is made up ofan amazing 100 trillion cells! But even you—like all other living things—began life as a single cell. More of thecell theory will be discussed in a later chapter.The Gene TheoryThegene theoryis the idea that the characteristics of living things are controlled by genes, which are passed fromparents to their offspring. Genes are located on larger structures, called chromosomes, that are found inside everycell. Chromosomes, in turn, contain large molecules known as DNA (deoxyribonucleic acid). Molecules of DNA areencoded with instructions that tell cells what to do. To see how this happens, click on the animation titledJourney15
1.3. Biology: The Study of Lifewww.ck12.orginto DNAat the link below.http://www.pbs.org/wgbh/nova/genome/dna.htmlHomeostasisHomeostasis, or keeping things constant, is not just a characteristic of living things. It also applies to nature as awhole. Consider the concentration of oxygen in Earth’s atmosphere. Oxygen makes up 21% of the atmosphere, andthis concentration is fairly constant. What keeps the concentration of oxygen constant? The answer is living things.Most living things need oxygen to survive, and when they breathe, they remove oxygen from the atmosphere. On theother hand, many living things, including plants, give off oxygen when they make food, and this adds oxygen to theatmosphere. The concentration of oxygen in the atmosphere is maintained mainly by the balance between these twoprocesses. A quick overview of homeostasis can be viewed athttp://www.youtube.com/watch?v=DFyt7FJn-UM.EvolutionEvolutionis a change in the characteristics of living things over time. Evolution occurs by a process called naturalselection. Innatural selection, some living things produce more offspring than others, so they pass more genes tothe next generation than others do. Over many generations, this can lead to major changes in the characteristics ofliving things. Evolution explains how living things are changing today and how modern living things have descendedfrom ancient life forms that no longer exist on Earth. As living things evolve, they generally become better suitedfor their environment. This is because they evolve adaptations. Anadaptationis a characteristic that helps a livingthing survive and reproduce in a given environment.Lesson Summary• Living things are distinguished from nonliving things on the basis of eight characteristics: response to theenvironment, growth and development, reproduction, homeostasis, metabolism, cells, organization, and evo-lution.• Four underlying principles form the basis of biology. They are cell theory, gene theory, homeostasis, andevolution.Lesson Review Questions1. List the eight characteristics of all living things.2. Identify four unifying principles of modern biology.3. Outline the levels of organization of a complex, multicellular organism such as a mouse, starting with the cell.4. What is homeostasis? Give an example.5. Describe examples of ways that you depend on other living things.6. Assume that you found an object that looks like a dead twig. You wonder if it might be a stick insect. How couldyou determine if it is a living thing?7. Explain how a population differs from a community.8. How is gene theory related to the theory of evolution?16
www.ck12.orgChapter 1.Introduction to Environmental Science1.4What does it mean to be sustainable?FIGURE 1.11Sustainabilityis a concept born out of the desire of humanity to continue to exist on planet Earth for a very longtime, perhaps the indefinite future. Possibly, the most succinct articulation of the issue can be found in the Reportof the World Commission on Environment and Development. The report entitled “Our Common Future” primarilyaddressed the closely related issue of Sustainable Development. The report, commonly know as the BrundtlandReport after the Commission Chair Gro Harlem Brundtland, stated that“Humanity has the ability to make development sustainable to ensure that itmeets the needs of the presentwithout compromising the ability of future generations to meet their own needs....Yet in the end, sustainabledevelopment is not a fixed state of harmony, but rather a process of change in which the exploitation of resources, thedirection of investments, the orientation of technological development, and institutional change are made consistentwith future as well as present needs. We do not pretend that the process is easy or straightforward. Painful choiceshave to be made. Thus, in the final analysis, sustainable development must rest on political will.”Sustainability and the closely related concept of Sustainable Development are, therefore, very human constructswhose objective is to insure the very survival of humanity in a reasonably civilized mode of existence.Theseriousness of the issue of sustainability has become increasingly important and obvious over the last fifty yearsdriven by an increasing human population with increasing per capita resource consumption on a planet which isafter all finite. Note that the World population increased from approximately 2.5 billion in 1950 to about 7.4 billionin 2016. Furthermore, total World consumption expenditures rose from about 171 Billion in 1960 to approximately44,000 billions in 2010 expressed in 2012 U.S. dollars. This is not to say that consumption is necessarily bad, butrather that there are so many people consuming so many resources that both the World environment and humanconsumption will have to be managed with far more care and delicacy than has been necessary in all of the historicalpast.The intersection of social and economic elements can form the basis of social equity. In the sense of enlightenedmanagement, "viability" is formed through consideration of economic and environmental interests. Between en-vironment and social elements lies “bearability,” the recognition that the functioning of societies is dependent onenvironmental resources and services. At the intersection of all three of these lies sustainability (see sustainability17
1.4. What does it mean to be sustainable?www.ck12.orgfigure above)FIGURE 1.12Datafromhttp://www.worldometers.info/world-population/ Collected on 8/22/2016Ecosystems SustainSustainable development has figured prominently on the international agenda for more than a quarter of a century.People talk earnestly of the environmental, social and economic dimensions of development. Yet we continue tobuild-up the economic component, at considerable cost to the environmental one. We risk undermining social andeconomic gains by failing to appreciate our fundamental dependency on ecological systems. Social and economicsustainability are only possible with a healthy planet. Ecosystems sustain societies that create economies. It doesnot work the other way round. But although human beings are a product of the natural world, we have become thedominant force that shapes ecological and biophysical systems. In doing so, we are not only threatening our health,prosperity and well-being, but our very future.This section was modified from Tom Theis and Jonathan Tomkin, Editors, Sustainability: A Comprehensive Founda-tion. OpenStax CNX. Jan 5, 2015 http://cnx.org/contents/1741effd-9cda-4b2b-a91e-003e6f587263@43.5@43.5.18
www.ck12.orgChapter 1.Introduction to Environmental ScienceFIGURE 1.1319
1.5. Environmental Issues Todaywww.ck12.org1.5Environmental Issues TodayFour Interrelated Environmental IssuesWhile there are numerous environmental problem in the world today, we will focus on four overarching problemsthat underlie most other issues. We will discuss these issues in depth throughout the course.1. Human Population Growth.2. Wasteful and Unsustainable Use of Resources3. Poverty.4. Market Values for goods do not take into account the true costs (including degradation of natural capitol).Overexploitation of Resources and the Tragedy of the CommonsThe concept of theTragedy of the Commonsis extremely important for understanding the degradation of ourenvironment. The concept was clearly expressed for the first time by Garrett Hardin in his now famous article inScience in 1968, which is "widely accepted as a fundamental contribution to ecology, population theory, economicsand political science." Hardin: University of California Santa Barbara.If a resource is held in common for use by all, then ultimately that resource will be destroyed. "Freedom ina common brings ruin to all." To avoid the ultimate destruction, we must change our human values and ideas ofmorality.• "Held in common" means the resource is owned by no one, or owned by a group, all of whom have access tothe resource.• "Ultimately" means after many years, maybe centuries. The time interval is closely tied to population increaseof those who have access to the resource. The greater the number of people using a resource, the faster it isdestroyed. Thus the Tragedy of the Commons is directly tied to over population.• The resource must be available for use. Iron in earth’s core is held in common, but it is inaccessible, and itwill not be destroyed.• Resources held by individuals, even if the individual destroys the resource, is not an example of the Tragedyof the Commons.• We can avoid tragedy only by altering our values, by changing the way we live. There is no technical solution.Examples of Common Resources• Air. No one owns the air, it is available for all to use, and its unlimited use leads to air pollution.• Water. Water in the seas, estuaries, and the ocean is a common resource. But, water in lakes and rivers is oftenowned by cities, farmers, or others, especially in the western US.• Fish of the sea.–Hardin writes that In 1625, the Dutch scholar Hugo Grotius said, "The extent of the ocean is in fact sogreat that it suffices for any possible use on the part of all peoples for drawing water, for fishing, forsailing." Now the once unlimited resources of marine fishes have become scarce and nations are comingto limit the freedom of their fishers in the commons. From here onward, complete freedom leads totragedy.20
www.ck12.orgChapter 1.Introduction to Environmental ScienceA General Statement of the Tragedy of the Commons1. The Earth is finite: it has a limited stock of renewable fuels, minerals, and biological resources, a limitedthroughput of energy from the sun, and a finite sink for processing wastes.2. Although human activity very often does occur on privately owned lands which are not a commons, that andall other human activities take place in some larger natural commons. And that larger commons is a limitedbiosystem which is in a dynamic, competitive, and constantly evolving equilibrium. The equilibrium of anecosystem can usually accommodate any activity on the part of its members as long as that activity is limited inamount and/or is practiced only by a small population. But continuous growth in the numbers of any organismor in its exploitation of land and resources will eventually exceed the capacity of the ecosystem to sustain thatorganism.3. Now for the first time on global scale human beings are exceeding the land and resource use which the Earth’sbiosystem can sustain.Some ConsequencesThe large and rapid increase in population since the beginning of the anthropocene has altered the global commons.Will our atmosphere, rivers, lands, and ocean ultimately be destroyed because they are held in common for use byall? Will we place ever stronger restrictions on their use? Or will we limit the population of the world?Individualism is cherished because it produces freedom, but the gift is conditional: The more the population exceedsthe carrying capacity of the environment, the more freedoms must be given up. As cities grow, the freedom to parkis restricted by the number of parking meters or fee-charging garages. Traffic is rigidly controlled. On the globalscale, nations are abandoning not only the freedom of the seas, but the freedom of the atmosphere, which acts asa common sink for aerial garbage. Yet to come are many other restrictions as the world’s population continues togrow.- Hardin (1998): Extensions of "The Tragedy of the Commons."ReferencesHardin, Garret. (1969) "The Tragedy of the Commons." Science. 162: 1243-8.Hardin, G. (1998)."ESSAYS ON SCIENCE AND SOCIETY: Extensions of "The Tragedy of the Commons."Science 280 (5364): 682-683.This section was modified from http://oceanworld.tamu.edu/resources/environment-book/Vocabularynm21
1.6. Looking Ahead with Hopewww.ck12.org1.6Looking Ahead with HopeWhile the environmental challenges that we face may seem overwhelming, I urge you not to get depressed about thefuture. As one traces societal attitudes, we have reason to hope that humans can change. And the way to get peopleto change their behavior is through hopeful goals rather than bleak outlooks and grim statistics.For an optimistic way to confront environmental problems, watch:Nic Marks: The Happy Planet IndexVocabularyAh22
www.ck12.orgChapter 1.Introduction to Environmental Science1.7References1. Image copyright Dennis Cox, 2014.http://www.shutterstock.com. Used under license from Shutterstock.com2. Hana Zavadska.CK-12 Foundation.3. Flickr:OakleyOriginalS.http://www.flickr.com/photos/oakleyoriginals/4536342259/. CC BY 2.04. Peter Shanks (Flickr:BotheredByBees).http://www.flickr.com/photos/botheredbybees/3152335109/.CCBY 2.05. Mariana Ruiz Villarreal (User:LadyofHats/Wikimedia Commons).http://commons.wikimedia.org/wiki/File:Greenfrog_life_stages.svg. Public Domain6. Human cells: Image copyright Sebastian Kaulitzki, 2014; Onion cells: Umberto Salvagnin.Human cells: http://www.shutterstock.com; Onion cells: http://www.flickr.com/photos/kaibara/3839720754. Human cells:Used under license from Shutterstock.com; Onion cells: CC BY 2.07. Mariana Ruiz Villarreal (User:LadyofHats/Wikimedia Commons).http://commons.wikimedia.org/wiki/File:Organization_levels_mouse.svg. Public Domain8. Christopher Auyeung.CK-12 Foundation. CC BY-NC 3.09. Archaebacteria: NASA; Bacteria: De Wood and Chris Pooley/Agricultural Research Service, USDA; Protist:Image copyright MichaelTaylor, 2014; Fungus: Tony Hisgett; Plant: Mauro Guanandi; Animal: úlfhams_-víkingur.Archaebacteria: http://commons.wikimedia.org/wiki/File:Halobacteria.jpg; Bacteria: http://commons.wikimedia.org/wiki/File:Campylobacter.jpg; Protist: http://www.shutterstock.com/; Fungus: http://www.flickr.com/photos/hisgett/4086503406/; Plant: http://www.flickr.com/photos/mauroguanandi/2194637211/; Animal: http://www.flickr.com/photos/24710622@N05/3230447306/.Archaebacteria, Bacteria: Public Do-main; Protist: Used under license from Shutterstock.com; Fungus, Plant, Animal: CC BY 2.010. Mariana Ruiz Villarreal (User:LadyofHats/Wikimedia Commons).http://commons.wikimedia.org/wiki/File:Timeline_evolution_of_life.svg. Public Domain11. .http://cdn1.footprintnetwork.org/Living_Planet_Report_2014_summary.pdf.23