Env Sci Exam 1 Review PDF

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Environmental Science: Exam 1 Review

Chapter 1: Environmental Science is Interdisciplinary

- Environmental science: an interdisciplinary field of research that draws on information (natural and social sciences, and the humanities) to understand the natural world and our relationship to it

- Natural sciences: ecology, geology, chemistry - Social sciences: anthropology, psychology, economics - Humanities: art, literature, music - Environment: the biological and physical surroundings in which any given organism exists.

- Environmental science is an empirical science, which is a scientific approach that investigates the natural world through systematic observation and experimentation.

- It’s also an applied science, which implies that it’s scientific process whose research findings help solve practical problems.

- Environmental literacy: basic understanding of how ecosystems function and how our choices may affect it.

- Trade-offs: the imperfect and sometimes problematic responses that we must at times choose between when addressing complex problems. (NO ULTIMATE SOLUTION)

- Triple bottom line: the combination of the environmental, social, and economic impacts of our choices.

- Sustainable Development: development that allows researchers to meet present needs without compromising the ability of future generations to do the same.

- Carrying Capacity: Population size that an area can support indefinitely (Overpopulation)

- Carrying capacity is constantly changing - Ecological Footprint: Environmental scientists evaluate the impact any population has on its environment

- Anthropogenic: caused or related to human action. - Sustainable: A method of using resources in such a way that we can continue to use them indefinitely

- Renewable Energy: Energy that comes from an infinitivley available or easily replenished source

- Biodiversity: The variety of species present - Nonrenewable Resources: A supply that is finite or is not replenished easily - Social Traps: Decisions by individuals or groups that seem good at the time and produce a short-term benefit, but that hurt society in the long run

- The Tragedy of the Commons: Tendency of an individual to abuse commonly held resources in order to maximize his or her own personal interest

- Time Delay: Actions that produce a benefit today set into motion events that cause problems later on

- Sliding Reinforcer: Actions that are beneficial at first but that change conditions such that their benefit declines over time

- Worldviews: The window through which we view our world and existence - Environmental Ethic: How a person interacts with his or her natural environment and thus affects how one responds to environmental problems

- Anthropocentric Worldview: A human-centered view that assigns intrinsic value to only humans

- Instrumental View: The value or worth of an object, organism, or species is based on how useful it is to humans

- Biocentric Worldview: A view that values all life, every organism has an inherent right to exist

- Intrinsic Value: The worth of an object, organism or species based on the fact that it exists

- Ecocentric Worldview: Values the ecosystem as an intact whole Greenland Vikings:

- After 450 years of prosperity, the Greenland vikings disappeared - Middens: garbage heaps that demonstrated how the vikings lived and died

- Contrary to back then, collapse today would seem to be associated to political or economical conflict

- Reason as to why Greenland vikings disappeared: People that went across Norway to Greenland that were not environmentally literate.

- Jared Diamond’s 5 factors that contribute to societal collapse - 1. Climate change: The little ice age (lower temps > livestock starved) Natural event

- 2. Environmental degradation: Soil erosion due to overgrazed land. Human choice / natural event

- 3. Inability or unwillingness to adapt or failure to respond to the natural environment: eg - not changing from beef to fish , not conserving wood (prioritized status) Human choice

- 4. Loss of friendly allies: European ships stopped trade with them Human choice

- 5. Hostility from enemies: they detested the Inuit and considered them inferior, didn’t seek for their help Human choice

- Why should we care about the decline of the Vikings in Greenland? - Understand their mistakes - Become literate in environmental issues - Live more sustainably - Similarities between modern humans and vikings: - We use farming practices that strip away topsoil and diminish land fertility

- We over harvest our forrest - We overfish and overhunt - Our attitudes prevent us from responding effectively to environmental changes

- Root of problem: disconnect in our understanding between our understanding of the relationship between our actions and environment

- Sustainability is the opposite of collapse

- Wealth inequality is a huge problem for sustainable growth - Wealthier nations are less affected by resource availability - Social traps:

Chapter 2: Ozone and the Scientific Process

- Science: a body of knowledge (facts and explanations) about the natural world and the process used to get that knowledge

- The scientific process is a powerful tool that allows us to gather our ideas and to evaluate the quality of that evidence.

- Empirical Evidence: information gathered via observation of physical phenomena

- Observations: information detected with the senses or with equipment that extends our senses

- Inferences: conclusions we draw based on observations - Atmosphere: the blanket of gases that surrounds Earth and other planets. - Troposphere: The region of the atmosphere that starts at ground level and extends upward about 7 miles

- Stratosphere: the region of the atmosphere that starts at the top of the troposphere and extends up about 31 miles; contains the ozone layer

- Ozone: a molecule with three oxygen atoms that absorbs UV radiation in the stratosphere

- UV radiation: short-wavelength electromagnetic energy emitted by the sun - What problems could emerge if the ozone layer lost some of its ozone?

- Less ozone in the ozone layer would allow more UVb and UBa radiation through. This could increase the risk of cancer and other damage caused by these UV rays

- Correlation: two things occurring together but not necessarily having a cause and effect relationship

- Cause and effect: an association between two variable that identifies one (the effect) occurring as a result of or in response to the other (the cause)

- Scientific method: the procedure scientists use to empirically test a hypothesis - 1. Observation - 2. question/hypothesis - 3. prediction - 4. experiment - 5. analyze - 6. conclusion - Hypothesis: a possible explanation for what we have observed that is based on some previous knowledge; must be testable and falsifiable.

- Testable: having a possible explanation that generates predictions for which empirical evidence can be collected to verify or refute the hypothesis

- Predictions: a statement that identifies what is expected to happen in a given situation

- Falsifiable: being capable of being proved wrong by evidence - Peer review: a process whereby researchers submit a report of their work to outside experts who evaluate the study's design and results to determine whether it is of a high enough quality to publish.

- Theory: a widely accepted explanation of a natural phenomenon that has been extensively and rigorously tested scientifically

- Observational study: research that gathers data in a real-world setting without intentionally manipulating any variable (observing relationship between skin cancer and Ozone size)

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Observe or measure existing phenomena Do not change or manipulate anything Generally involves field work Generally involves large, complex systems that are hard or impossible to replicate in the lab

- Generally involves large, complex systems that are hard or impossible to replicate in the lab

- Also called comparative studies - Experimental study: research that manipulates a variable in a test group and compares the response to that of a control group that was not exposed to the same variable (study with mice)

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Change one variable and see how it affects other(s) Control and experimental groups Generally involves lab work Very simplified model of nature – findings may not always be applicable outside the lab

- Can definitively show causation - Control group: the group in an experimental study that the test group's results are compared to; ideally, the control group will differ from the test group in only one way

- Test group: the group in an experimental study that is manipulated such that it differs from the control group in only one way

- Independent variable: the variable in an experiment that a researcher manipulates or changes to see if the change produces an effect

- Dependent variable: the variable in an experiment that is evaluated to see if it changes due to the conditions of the experiment

- Control variable: all other things should be held constant during the experiment - Statistics: the mathematical evaluation of experimental data to determine how likely it is that any difference observed is due to the variable being tested

- Montreal Protocol: an international treaty that laid out plans to phase out ozonedepleting chemicals such as CFCs

- Policy: a formalized plan that addresses a desired outcome or goal - Precautionary principle: a principle that encourages acting in a way that leaves a margin of safety when there is a potential for serious harm but uncertainty about the form or magnitude of that harm

- Adaptive management: a plan that allows room for altering strategies as new information becomes available or as the situation itself changes

- Layers of atmosphere: Starting from bottom: Troposphere, Stratosphere, Mesosphere, Thermosphere, Exosphere

- What depletes ozone? Chlorofluorocarbons (CFCs) - human made molecules - Replication: repetition of treatments; conducting the experiment may times Ozone Hole

- Do CFCs, or more specifically Cl, destroy O3? - Lab work showed Cl breaks down O3; chemical makeup of stratosphere

- Why and when was the O3 layer above the South Pole disappearing? - Location and timing of O3 hole; change over time in O3 and ClO in stratosphere

- Is O3 depletion causing more skin cancer? - Results from expt. lab studies in mice that expose them to UV AND observational studies of people

- How was the precautionary principle applied to the problem of the ozone hole? - The Montreal protocol - Scientific Questions should be: - Specific - Generally have to do with causal relationships, patterns, differences between groups (“is/will be”)

- Do NOT have to do with morality, philosophy, etc (“should”) - Can be supported or falsified with data that, at least theoretically, can be observed or generated

- Scientific Questions should be: - Specific - Generally have to do with causal relationships, patterns, differences between groups (“is/will be”)

- Do NOT have to do with morality, philosophy, etc (“should”) - Can be supported or falsified with data that, at least theoretically, can be observed or generated

Chapter 3: Toxins

- Toxic substances / toxics: Chemicals that cause direct damage upon exposure - Natural toxics can be as harmful as synthetic ones - Combination of experimental and observational studies to determine toxicity

- Persistent Chemicals: Chemicals that do not degrade over time - 1,000-2,000 enter the consumer market each year - Risk Assessment: A careful weighing of the risks and benefits associated with any given chemical

- Regulations begin with risk assessments - Precautionary principle: The rule of thumb that calls for leaving a wide safety margin when setting the exposure limit- the maximum quantity humans can safely be exposed to (better safe than sorry principle)

- More common in EU than in US (innocent until proven guilty) - Information Literacy: Ability to find and evaluate the quality of information - Primary sources: Sources that present new and original data or information - Peer Review: A process where researchers submit a report of their work to outside experts who evaluate they study's design and results to determine if it is of a high-enough quality to publish

- Secondary Sources: present and interpret information from primary sources (Include newspaper, magazines, books and most information from the Internet.)

- Tertiary sources: Sources that present and interpret information from secondary sources

- Persistence: How long it takes the substance to break down in the environment - Solubility: ability of a substance to break down in liquid - Bioaccumulation: The buildup of fat-soluble substances in the tissue of an organism over the course of its lifetime (occurs in the individual)

- Biomagnification: A consequence of bioaccumulation- its what happens when animals that are high up on the food chain eat other animals that have bioaccumulated toxins (they consume their prey's entire lifetime dose of toxins) (occurs as a food chain phenomenon)

- Epidemiologists: A scientist who studies the cause and patterns of disease in human populations

- Toxicologists: A scientist who studies the specific properties of any given potential toxin

- In vivo: (in the body) studies the effects of an experimental treatment in intact organisms

- In vitro: Research that studies the effects of experimental treatment cells in culture dishes rather than in intact organisms

- Additive effect of toxins: Exposure of two or more chemicals has an effect equivalent to the sum of their individual effects

- Antagonistic Effects: Exposure to two or more chemicals has a lesser effect than the sum of their individual effects would predict

- Synergistic Effects: Exposure to two or more chemicals has a greater effect than the sum of their individual effects would predict

- Endocrine disruptor: A molecule that interferes with the endocrine system, typically mimicking a hormone

- Low doses can have different (and sometimes worse) effects than high doses

- Hormones: chemical messengers that coordinate numerous bodily functions

- Can particularly affect developing fetuses and young children - Receptor: A structure on or in the cell that binds a hormone and allows the hormone to affect the cell

- Dose-response curve: A graph that effects a substance at different concentrations or levels of exposure

- LD50 (Lethal Dose 50%): The dose of a substance that would kill 50% of the test population

- Logical Fallacies: Arguments that are used to sway the reader with out using actual facts

Chapter 3: Information Literacy and Toxicology

- Flint Michigan: - 40% of pop live in poverty - city changed water sources to Flint River - residents complained about color, odor and taste of water - GM stops using Flint River, citing high metal concentrations and high chlorine levels, used to treat bacterial contamination

- EPA limit for safe drinking water is 15 part per billion (Flint Measured at 113 ppb)

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Knowing how to respond to the latest toxic scare is often difficult due to conflicting messages

- Synthetic chemicals are long-lasting in the environment and not fully removed by water treatment. Typically the the body tissues of most people

- Types of toxins: - Natural - Synthetic - Water soluble - Fat-soluble - Carcinogens: cause cancer

- Mutagens: damage DNA directly - Can cause cancer or disrupt normal body function - Types and effects of substances: - Teratogens: substances that cause birth defects by disrupting normal embryonic development

- Endocrine disruptors (e.g., BPA): chemicals that interfere with the body’s system of hormones

- Poisons (e.g., lead): damage or kill cells, or disrupt biochemical processes

- Types of effects: - Acute: rapid adverse reaction that occurs after exposure - Chronic: repeated long-term exposure to low doses of a toxic substance causes an adverse reaction (e.g., smoking cigarettes daily and developing lung cancer later in life)

- Factors that determine toxicity: - Potency: dose size required for a chemical to cause harm - BPA – different effects @ low and high doses - Lead – highly potent @ any dose - Persistence: measure of how resistant a chemical is to degradation - BPA – low persistence - Lead – high persistence - Solubility: ability of a substance to dissolve in a water- or fat-based liquid or gas

- Bioaccumulation vs biomagnification - BPA: -

Synthetic molecule Binds to body’s cellular estrogen receptors Triggers the same effects that actual estrogen would trigger Biological effects at low doses Starting material of plastics

- Component of many human made products (plastics of all kinds, lining of metal cans)

- Lead: - lead affects children more than adults - GI tracts absorb more of it - Brains and blood–brain barriers are not yet fully developed. - Naturally occurring element (metal) - Used in water pipes - Formerly an important component of gasoline - Factors that affect toxicity: Exposure, victim traits, chemical interactions - Certain toxins can have more serious effects on one person or group of people than another.

- The route of exposure and the dose of that exposure (Inhalation, dermal, ingestion)

- Some people are genetically predisposed to be more or less sensitive to a chemical

- Illness may also make a person more vulnerable. - Additionally, affects can be additive, antagonistic, or synergistic Chapter 4: One Child China Grows Up

- Population growth rate: The percent increase of population size over time; affected by births, deaths, and the # of people moving into or out of a regional population

- Takes into account the number of births and deaths as well as immigration and emigration numbers

- Life expectancy: The # of years someone is expected to live - Crude death rate: # of deaths per 1,000 people per year - Less variable worldwide

- Crude birth rate: # of offspring born per 1,000 people per year - Tends to be almost twice as high in less developed countries - Population Density: # of people per unit area - Overpopulation: More people living in an area than its natural and human resources can support

- It depends on several factors, including how many resources people use and how much waste they produce.

- Population momentum: The tendency of a young population to continue to grow even after birth rates drop to replacement rates

- Infant mortality rate: # of infants who die in their 1st year of life per every thousand live births in that year

- Total fertility rate: # of children the average woman has in her lifetime - Demographic factors: Population characteristics such as birth rate or life expectancy that influence how a population changes in size and composition

- Zero Population Growth: The absence of population growth; occurs when birth rates equal death rates

- Replacement Fertility Rate: The rate at which children mu...