Principles of Environmental Science

Title Page
Copyright Information
About the Authors
Brief Contents
Contents
Preface
Acknowledgments
Connect
Guided Tour
Preface
1 Understanding Our Environment
	LEARNING OUTCOMES
	Case Study   Sustainability and Power on the Reservation
	1.1   What is Environmental Science?
		Environmental science integrates many fields
		Environmental science is global
	Active Learning   Finding Your Strengths in This Class
		Environmental science helps us understand our remarkable planet
		Methods in environmental science
	1.2   Major Themes in Environmental Science
		Environmental quality
		Human population and well-being
		Natural resources
	1.3   Human Dimensions of Environmental Science
		How do we describe resource use and conservation?
		Planetary boundaries
		Sustainability requires environmental and social progress
	Key Concepts   Sustainable development
		What is the state of poverty and wealth today?
		Indigenous peoples safeguard biodiversity
	1.4   Science Helps Us Understand Our World
		Science depends on skepticism and reproducibility
		We use both deductive and inductive reasoning
		The scientific method is an orderly way to examine problems
		Understanding probability reduces uncertainty
		Experimental design can reduce bias
	Active Learning   Calculating Probability
		Science is a cumulative process
	Exploring Science   Understanding sustainable development with statistics
		What is sound science?
	What Do You Think?   Science and Citizenship: Evidence-Based Policy vs. Policy-Based Evidence?
		Uncertainty, proof, and group identity
	1.5   Critical Thinking
		Critical thinking is part of science and of citizenship
	1.6   Where Do Our Ideas About the Environment Come From?
		Environmental protection has historic roots
		Resource waste triggered pragmatic resource conservation (stage 1)
		Ethical and aesthetic concerns inspired the preservation movement (stage 2)
		Rising pollution levels led to the modern environmental movement (stage 3)
		Environmental quality is tied to social progress (stage 4)
	Conclusion
	Data Analysis   Working with Graphs
2 Environmental Systems: Matter, Energy, and Life
	LEARNING OUTCOMES
	Case Study   Death by Fertilizer: Hypoxia in the Gulf of Mexico
	2.1   Systems Describe Interactions
		Systems can be described in terms of their characteristics
		Feedback loops help stabilize systems
	2.2   Elements of Life
		Matter is recycled but not destroyed
		Elements have predictable characteristics
		Electrical charges keep atoms together
		Water has unique properties
		Acids and bases release reactive H+ and OH-
		Organic compounds have a carbon backbone
		Cells are the fundamental units of life
		Nitrogen and phosphorus are key nutrients
	What Do You Think?   Gene Editing
	2.3   Energy and Living Systems
		Energy occurs in different types and qualities
		Thermodynamics describes the conservation and degradation of energy
		Organisms live by capturing energy
		Green plants get energy from the sun
		How does photosynthesis capture energy?
	2.4   From Species to Ecosystems
		Organisms occur in populations, communities, and ecosystems
		Food chains, food webs, and trophic levels define species relationships
	Active Learning   Food Webs
	Key Concepts   How do energy and matter move through systems?
	Exploring Science   Who Cares About Krill?
		Ecological pyramids describe trophic levels
	2.5   Biogeochemical Cycles and Life Processes
		The hydrologic cycle
		The carbon cycle
		The nitrogen cycle
		Phosphorus eventually washes to the sea
		The sulfur cycle
	Conclusion
	Data Analysis   A Closer Look at Nitrogen Cycling
3 Evolution, Species Interactions, and Biological Communities
	LEARNING OUTCOMES
	Case Study   Natural Selection and the Galápagos Finches
	3.1   Evolution Leads to Diversity
		Natural selection and adaptation modify species
		Limiting factors influence species distributions
		A niche is a species’ role and environment
		Speciation leads to species diversity
		Taxonomy describes relationships among species
	Key Concepts   Where do species come from?
	3.2   Species Interactions
		Competition leads to resource allocation
		Predation affects species relationships
		Predation leads to adaptation
		Symbiosis involves cooperation
	Exploring Science   Say Hello to Your 90 Trillion Little Friends
		Keystone species play critical roles
	3.3   Population Growth
		Growth without limits is exponential
		Carrying capacity limits growth
		Environmental limits lead to logistic growth
		Species respond to limits differently: r- and K-selected species
	Active Learning   Effect of K on Population Growth Rate (rN)
	3.4   Community Diversity
		Diversity and abundance
		Patterns produce community structure
	What Can You Do?   Working Locally for Ecological Diversity
		Resilience seems related to complexity
	3.5   Communities Are Dynamic and Change over Time
		Are communities organismal or individualistic?
		Succession describes community change
		Some communities depend on disturbance
	Conclusion
	Data Analysis   Competitive Exclusion
4 Human Populations
	LEARNING OUTCOMES
	Case Study   Family Planning in Thailand: A Success Story
	4.1   Past and Current Population Growth Are Very Different
		Human populations grew slowly until recently
	Active Learning   Population Doubling Time
		Does environment or culture control human population growth?
		Technology increases carrying capacity for humans
		Population can push economic growth
	4.2   Many Factors Determine Population Growth
		How many of us are there?
	Key Concepts   How big is your footprint?
		Fertility has declined in recent decades
		Mortality offsets births
		Life expectancy is rising worldwide
	What Do You Think?   China’s One-Child Policy
		Living longer has profound social implications
	4.3   Fertility Is Influenced by Culture
		People want children for many reasons
		Education and income affect the desire for children
	4.4   The Demographic Transition
		Economic and social conditions change mortality and births
		Two ways to complete the demographic transition
		Improving women’s lives helps reduce birth rates
		Family planning gives us choices
	4.5   What Kind of Future Are We Creating Now?
	Conclusion
	Data Analysis   Population Change over Time
5 Biomes and Biodiversity
	LEARNING OUTCOMES
	Case Study   Ecosystems in Transition
	5.1   Terrestrial Biomes
		Tropical moist forests are warm and wet year-round
		Tropical seasonal forests have annual dry seasons
	Active Learning   Comparing Biome Climates
		Tropical savannas and grasslands are dry most of the year
		Deserts are hot or cold, but always dry
		Temperate grasslands have rich soils
		Temperate scrublands have summer drought
		Temperate forests can be evergreen or deciduous
		Boreal forests lie north of the temperate zone
		Tundra can freeze in any month
	5.2   Marine Environments
	Active Learning   Examining Climate Graphs
		Open ocean communities vary from surface to hadal zone
		Tidal shores support rich, diverse communities
	5.3   Freshwater Ecosystems
		Lakes have extensive open water
		Wetlands are shallow and productive
		Streams and rivers are open systems
	5.4   Biodiversity
		Increasingly we identify species by genetic similarity
		Biodiversity hot spots are rich and threatened
		Biodiversity provides food and medicines
	5.5   What Threatens Biodiversity?
		HIPPO summarizes human impacts
		Habitat destruction is usually the main threat
	Key Concepts   What is biodiversity worth?
		Fragmentation reduces habitat to small, isolated areas
		Invasive species are a growing threat
	What Can You Do?   You Can Help Preserve Biodiversity
		Pollution poses many types of risk
		Population growth consumes space, resources
		Overharvesting depletes or eliminates species
	Exploring Science   Restoring Coral Reefs
	5.6   Biodiversity Protection
		Hunting and fishing laws protect useful species
		The Endangered Species Act protects habitat and species
		Recovery plans aim to rebuild populations
		Landowner collaboration is key
		The ESA has seen successes and controversies
		Many countries have species protection laws
		Habitat protection may be better than individual species protection
	Conclusion
	Data Analysis   Confidence Limits in the Breeding Bird Survey
6 Environmental Conservation: Forests, Grasslands, Parks, and Nature Preserves
	LEARNING OUTCOMES
	Case Study   Palm Oil and Endangered Species
	6.1   World Forests
		Boreal and tropical forests are most abundant
	Active Learning   Calculating Forest Area
		Forests provide essential products
		Tropical forests are being cleared rapidly
	Exploring Science   How Can We Know About Forest Loss?
		Saving forests stabilizes our climate
		REDD schemes can pay for ecosystem services
		Temperate forests also are at risk
	Key Concepts   Save a tree, save the climate?
	What Can You Do?   Lowering Your Forest Impacts
		Fire management is a growing cost
		Ecosystem management is part of forest management
	6.2   Grasslands
		Grazing can be sustainable or damaging
		Overgrazing threatens many rangelands
		Ranchers are experimenting with new methods
	6.3   Parks and Preserves
		Many countries have created nature preserves
		Not all preserves are preserved
	What Do You Think?   Wildlife or Oil?
		Marine ecosystems need greater protection
		Conservation and economic development can work together
		Native people can play important roles in nature protection
	What Can You Do?   Being a Responsible Ecotourist
	Citizenship Science   Monuments Under Attack
		Species survival can depend on preserve size and shape
	Conclusion
	Data Analysis   Detecting Edge Effects
7 Food and Agriculture
	LEARNING OUTCOMES
	Case Study   A New Pesticide Cocktail
	7.1   Global Trends in Food and Hunger
		Food security is unevenly distributed
		Famines have political and social roots
	Active Learning   Mapping Poverty and Plenty
	7.2   How Much Food Do We Need?
		A healthy diet includes the right nutrients
		Overeating is a growing world problem
		More production doesn’t necessarily reduce hunger
		Biofuels have boosted commodity prices
		Do we have enough farmland?
	7.3   What Do We Eat?
		Rising meat production is a sign of wealth
		Seafood, both wild and farmed, depends on wild-source inputs
		Biohazards arise in industrial production
	7.4   Living Soil Is a Precious Resource
		What is soil?
	Active Learning   Where in the World Did You Eat Today?
		Healthy soil fauna can determine soil fertility
		Your food comes mostly from the A horizon
		How do we use and abuse soil?
		Water is the leading cause of soil erosion
		Wind is a close second in erosion
	7.5   Agricultural Inputs
		High yields usually require irrigation
	Key Concepts   How can we feed the world?
		Fertilizers boost production
		Modern agriculture runs on oil
		Pesticide use continues to rise
	7.6   How Have We Managed to Feed Billions?
		The Green Revolution has increased yields
		Genetic engineering has benefits and costs
		Most GMOs are engineered for pesticide production or pesticide tolerance
		Is genetic engineering safe?
	7.7   Sustainable Farming Strategies
		Soil conservation is essential
		Groundcover, reduced tilling protect soil
		Low-input, sustainable agriculture can benefit people and the environment
		Consumer choices benefit local farm economies
	What Do You Think?   Shade-Grown Coffee and Cocoa
		You can eat low on the food chain
	Conclusion
	Data Analysis   Mapping Your Food Supply
8 Environmental Health and Toxicology
	LEARNING OUTCOMES
	Case Study   A Toxic Flood
	8.1   Environmental Health
		The global disease burden is changing
		Emergent and infectious diseases still kill millions of people
		Conservation medicine combines ecology and health care
		Resistance to antibiotics and pesticides is increasing
	What Can You Do?   Tips for Staying Healthy
	8.2   Toxicology
		How do toxics affect us?
		Is your shampoo making you fat?
	Key Concepts   What toxins and hazards are present in your home?
	8.3   Movement, Distribution, and Fate of Toxins
		Solubility and mobility determine when and where chemicals move
		Exposure and susceptibility determine how we respond
		Bioaccumulation and biomagnification increase chemical concentrations
		Persistence makes some materials a greater threat
		Chemical interactions can increase toxicity
	8.4   Toxicity and Risk Assessment
		We usually test toxic effects on lab animals
		There is a wide range of toxicity
		Acute versus chronic doses and effects
	Active Learning   Assessing Toxins
		Detectable levels aren’t always dangerous
		Low doses can have variable effects
		Our perception of risks isn’t always rational
	Exploring Science   The Epigenome
		How much risk is acceptable?
	Active Learning   Calculating Probabilities
	8.5   Establishing Health Policy
	Conclusion
	Data Analysis   How Do We Evaluate Risk and Fear?
9 Climate
	LEARNING OUTCOMES
	Case Study   Shrinking Florida
	9.1   What Is the Atmosphere?
		The atmosphere captures energy selectively
		Evaporated water stores and redistributes heat
		Ocean currents also redistribute heat
	9.2   Climate Changes Over Time
		Ice cores tell us about climate history
		What causes natural climatic swings?
		El Niño/Southern Oscillation is one of many regional cycles
	9.3   How Do We Know the Climate Is Changing Faster Than Usual?
		Scientific consensus is clear
	Active Learning   Can you explain key evidence on climate change?
		Rising heat waves, sea level, and storms are expected
		The main greenhouse gases are CO2, CH4, and N2O
		We greatly underestimate methane emissions
		What does 2˚ look like?
		Ice loss produces positive feedbacks
	Key Concepts   Climate change in a nutshell: How does it work?
	Exploring Science   How Do We Know That Climate Change Is Human-Caused?
		Climate change will cost far more than climate protection
		Why are there disputes over climate evidence?
	9.4   Envisioning Solutions
		The Paris Accord establishes new goals
		We have many drawdown options right now
		Wind, water, and solar could meet all our needs
	What Do You Think?   Unburnable Carbon
	What Can You Do?   Climate Action
		Local initiatives are everywhere
		States are leading the way
		Carbon capture saves CO2 but is expensive
	Conclusion
	Data Analysis   Examining the IPCC Fifth Assessment Report (AR5)
10 Air Pollution
	LEARNING OUTCOMES
	Case Study   Delhi’s Air Quality Crisis
	10.1   Air Pollution and Health
		The Clean Air Act regulates major pollutants
		Conventional pollutants are abundant and serious
	Active Learning   Compare Sources of Pollutants
		Hazardous air pollutants can cause cancer and nerve damage
		Mercury is a key neurotoxin
		Indoor air can be worse than outdoor air
	10.2   Air Pollution and Climate
		Air pollutants travel the globe
		CO2 and halogens are key greenhouse gases
		The Supreme Court has charged the EPA with controlling greenhouse gases
	Exploring Science   Black Carbon
		CFCs also destroy ozone in the stratosphere
		CFC control has had remarkable success
	10.3   Environmental and Health Effects
		Acid deposition results from SO4 and NOx
		Urban areas endure inversions and heat islands
		Smog and haze reduce visibility
	10.4   Air Pollution Control
		The best strategy is reducing production
		Clean air legislation has been controversial but extremely successful
		Trading pollution credits is one approach
	10.5   The Ongoing Challenge
		Pollution persists in developing areas
		Change is possible
	Key Concepts   Can we afford clean air?
	Conclusion
	Data Analysis   How Polluted Is Your Hometown?
11 Water: Resources and Pollution
	LEARNING OUTCOMES
	Case Study   A Water State of Emergency
	11.1   Water Resources
		How does the hydrologic cycle redistribute water?
		Major water compartments vary in residence time
		Groundwater storage is vast and cycles slowly
		Surface water and atmospheric moisture cycle quickly
	Active Learning   Mapping the Water-Rich and Water-Poor Countries
	11.2   How Much Water Do We Use?
		We export “virtual water”
		Some products are thirstier than others
		Industrial uses include energy production
		Domestic water supplies protect health
	11.3   Dealing with Water Scarcity
		Drought, climate, and water shortages
	What Do You Think?   Water and Power
		Groundwater supplies are being depleted
		Diversion projects redistribute water
		Questions of justice often surround dam projects
		Would you fight for water?
		Land and water conservation protect resources
		Everyone can help conserve water
	What Can You Do?   Saving Water and Prevenvting Pollution
		Communities are starting to recycle water
	11.4   Water Pollutants
		Pollution includes point sources and nonpoint sources
		Biological pollution includes pathogens and waste
		Nutrients cause eutrophication
		Inorganic pollutants include metals, salts, and acids
	Exploring Science   Inexpensive Water Purification
		Organic chemicals include pesticides and industrial substances
		Is bottled water safer?
		Sediment is one of our most abundant pollutants
	11.5   Persistent Challenges
		Developing countries often have serious water pollution
		Groundwater is especially hard to clean up
		Ocean pollution has few controls
	11.6   Water Treatment and Remediation
		Impaired water can be restored
		Nonpoint sources require prevention
		How do we treat municipal waste?
		Municipal treatment has three levels of quality
		Natural wastewater treatment can be an answer
		Remediation can involve containment, extraction, or biological treatment
	Key Concepts   Could natural systems treat our wastewater?
	11.7   Legal Protections for Water
		The Clean Water Act was ambitious, popular, and largely successful
		The CWA helped fund infrastructure
		The CWA established permitting systems
		The CWA has made real but incomplete progress
	Conclusion
	Data Analysis   Graphing Global Water Stress and Scarcity
12 Environmental Geology and Earth Resources
	LEARNING OUTCOMES
	Case Study   Salmon or Copper?
	12.1   Earth Processes Shape Our Resources
		Earth is a dynamic planet
		Tectonic processes reshape continents and cause earthquakes
	12.2   Minerals and Rocks
		The rock cycle creates and recycles rocks
		Weathering and sedimentation
		Economic Geology and Mineralogy
		Metals are essential to our economy
		Nonmetal mineral resources include gravel, clay, glass, and salts
		Currently, the earth provides almost all our fuel
	12.3   Environmental Effects of Resource Extraction
	Active Learning   What Geologic Resources Are You Using Right Now?
	Key Concepts   Where does your cell phone come from?
		Mining and drilling can degrade water quality
	Exploring Science   Induced Seismicity
		Surface mining destroys landscapes
		Processing contaminates air, water, and soil
		Recycling saves energy as well as materials
		New materials can replace mined resources
	12.4   Geologic Hazards
		Earthquakes are frequent and deadly hazards
		Volcanoes eject deadly gases and ash
		Floods are part of a river’s land-shaping processes
		Flood control
		Mass wasting includes slides and slumps
		Erosion destroys fields and undermines buildings
	Conclusion
	Data Analysis   Exploring Recent Earthquakes
13 Energy
	LEARNING OUTCOMES
	Case Study   Greening Gotham: Can New York Reach an 80 by 50 Goal?
	13.1   Energy Resources
		The future of energy is not the past
		We measure energy in units such as J and W
		How much energy do we use?
	13.2   Fossil Fuels
		Coal resources are greater than we can use
		Coal use is declining in the United States
		When will we run out of oil?
		Extreme oil and tar sands extend our supplies
		Access to markets is a key challenge
		Natural gas is growing in importance
		Hydraulic fracturing opens up tight gas resources
	13.3   Nuclear Power and Hydropower
		How do nuclear reactors work?
	What Do You Think?   Twilight for Nuclear Power?
		We lack safe storage for radioactive waste
		Moving water is one of our oldest power sources
		Large dams have large impacts
	13.4   Energy Efficiency and Conservation
	What Can You Do?   Steps to Save Energy and Money
		Costs can depend on how you calculate them
	Active Learning   Driving Down Gas Costs
		Tight houses save money
		Passive housing is becoming standard in some areas
		Cogeneration makes electricity from waste heat
	13.5   Wind and Solar Energy
		Wind could meet all our energy needs
		Wind power provides local control of energy
		Solar thermal systems collect usable heat
		CSP makes electricity from heat
		Photovoltaic cells generate electricity directly
	Key Concepts   How can we transition to alternative energy?
	13.6   Biomass and Geothermal Energy
		Ethanol has been the main U.S. focus
		Cellulosic ethanol remains mostly uneconomical
		Methane from biomass is efficient and clean
		Heat pumps provide efficient cooling and heating
	13.7   What Does an Energy Transition Look Like?
		The grid will need improvement
		Storage options are changing rapidly
		Fuel cells release electricity from chemical bonding
		Wind, water, and solar are good answers
	Conclusion
	Data Analysis   Personal Energy Use
14 Solid and Hazardous Waste
	LEARNING OUTCOMES
	Case Study   Plastic Seas
	14.1   What Waste Do We Produce?
		The waste stream is everything we throw away
	14.2   Waste Disposal Methods
		Open dumps release hazardous substances into the air and water
		Ocean dumping is mostly uncontrolled
		Landfills receive most of our waste
	Active Learning   Life-Cycle Analysis
		We often export waste to countries ill-equipped to handle it
		Incineration produces energy from trash
	What Do You Think?   Who Will Take Our Waste?
	14.3   Shrinking the Waste Stream
		Recycling saves money, energy, and space
	Key Concepts   Garbage: Liability or resource?
		Composting recycles organic waste
		Reuse is even better than recycling
		Reducing waste is the cheapest option
	What Can You Do?   Reducing Waste
	14.4   Hazardous and Toxic Wastes
		Hazardous waste includes many dangerous substances
	Active Learning   A Personal Hazardous Waste Inventory
		Federal legislation regulates hazardous waste
		Superfund sites are listed for federally funded cleanup
		Brownfields present both liability and opportunity
		Hazardous waste must be processed or stored permanently
	Exploring Science   Bioremediation
	Conclusion
	Data Analysis   How Much Waste Do You Produce, and How Much Do You Know How to Manage?
15 Economics and Urbanization
	LEARNING OUTCOMES
	Case Study   Using Economics to Fight Climate Change
	15.1   Cities Are Places of Crisis and Opportunity
		Large cities are expanding rapidly
		Immigration is driven by push and pull factors
		Congestion, pollution, and water shortages plague many cities
		Many cities lack sufficient housing
	15.2   Urban Planning
		Transportation is crucial in city development
	Key Concepts   What makes a city green?
		Rebuilding cities
		We can make our cities more livable
		Sustainable urbanism incorporates smart growth
	15.3   Economics and Resource Management
		Our definitions of resources influence how we use them
		Ecological economics incorporates principles of ecology
		Scarcity can lead to innovation
		Communal property resources are a classic problem in economics
	15.4   Natural Resource Accounting
	Exploring Science   What’s the Value of Nature?
	Active Learning   Costs and Benefits
		Internalizing external costs
		New approaches measure real progress
	What Can You Do?   Personally Responsible Consumerism
	15.5   Trade, Development, and Jobs
		Microlending helps the poorest of the poor
		Market mechanisms can reduce pollution
	Active Learning   Try Your Hand at Microlending
		Green business and green design
	Science and Citizenship   Green Energy Jobs Versus Fossil Fuels
		Green business creates jobs
	Conclusion
	Data Analysis   Plotting Trends in Urbanization and Economic Indicators
16 Environmental Policy and Sustainability
	LEARNING OUTCOMES
	Case Study   Fossil Fuel Divestment
	16.1   Environmental Policy and Science
		What drives policymaking?
		Policy creation is ongoing and cyclic
		Are we better safe than sorry?
	16.2   Major Environmental Laws
	Active Learning   Environment, Science, and Policy in Your Community
		NEPA (1969) establishes public oversight
		The Clean Air Act (1970) regulates air emissions
		The Clean Water Act (1972) protects surface water
		The Endangered Species Act (1973) protects wildlife
		The Superfund Act (1980) addresses hazardous sites
	16.3   How Are Policies Implemented?
		The legislative branch establishes statutes (laws)
		The judicial branch resolves legal disputes
	Key Concepts   How does the Clean Water Act benefit you?
		The executive branch oversees administrative rules
		How much government do we want?
	16.4   International Policies
		Major international agreements
		Enforcement often relies on national pride
	16.5   What Can Students Do?
		Working together gives you influence, and it’s fun
		New groups and approaches are emerging
		Find your own niche
	What Can You Do?   Actions to Influence Environmental Policy
		Environmental literacy integrates science and policy
		Colleges and universities are powerful catalysts for change
	Science and Citizenship   Water Protectors at Standing Rock
		Audits help reduce resource consumption
		Campus rankings motivate progress
		How much is enough?
	16.6   The Challenges of Sustainable Development
		Sustainable Development Goals aim to improve conditions for all
	Conclusion
	Data Analysis   Campus Environmental Audit
Appendix 1   Vegetation
Appendix 2   World Population Density
Appendix 3   Temperature Regions and Ocean Currents
Glossary
Index