Intro to Environmental Studies
Rules of Sustainability
1. Everything must cycle
2. Population must be limited and vary inversely with resource use per capita
3. Equity must be maintained
Environmental Studies
1. Natural Science
2. Values
3. Policy
4. Economics
Correctness of measurement, the right answer
Repeatability of results, narrowing down the uncertainty
Deductive reasoning
Logical reasoning from general to specific
a methodical, logical process for producing knowledge about natural phenomena.
• a cumulative body of knowledge produced by scientists.
• based on careful observation and hypothesis testing
Inductive reasoning
Reasoning from many observations to produce a general rule
A testable explanation
Scientific Theory
a description or explanation that has been supported by a large number of tests and is considered by experts to be a reliable
Scientific Method
1. Identify
2. Form testable hypothesis
3. Collect data to test hypothesis
4. Interpret results
5. Submit for peer review
6. Publish
Measure of how likely something is to occur
Natural experiment
involves observation of events that have already happened
manipulative experiment
conditions are deliberately altered and all other variables are held constant
Dependent is on the Y, independent is on the X
Descriptive Ethics
Describes what one ought to do. Tells us how the world is
Normative Ethics
Tells us how the world should be
Emphasis on consequences. John Stuart Mill
Emphasis on duty/obligation. Immanuel Kant
Virtue Ethics
Emphasis on character, how one should live. Aristotle
What is valuable to humans
Views oriented around life. Have reverence for life, entities with interests. Singer, Regan
Land ethic, Deep ecology. Allows for species and ecosystems
Impact on the environment is a combination of: Population, Affluence, Technology
encompasses vital statistics about people such as births, deaths, distribution, and population size.
Population growth in the last few centuries
1. Increase in commerce and communication
2. Agricultural revolution
3. Use of fossil fuel energy
4. Improvements in health care, hygiene
Population growth rate
Depends on
1. How many children are born (natural growth rate)
2. The age when women give birth
3. Death rate (natural growth rate)
4. Immigration (total growth rate)
5. Emigration (total growth rate)
Life expectancy
Average age an infant can expect to reach in any given society
Crude Death Rate
Number of deaths per thousand people in any given year
Crude Birth rate
Number of births per year per thousand
Total Fertility Rate
Total children born to an average women during her lifetime
Population growth equation
Population (t) = population (t-1)*e(k*t) : population at some later
time (t) = population at an earlier time (t-1) * 2.718(growth rate*time)

You can guess at a doubling time by 70/R where R is the rate

Pre-modern society
Poor living conditions keep death rates high, thus birth rates are correspondingly high
Thomas Malthus
Human populations increase exponentially and eventually outstrip food supply and collapse
Carl Marx
Population growth is an outcome of poverty and other social inequalities. Exploitation and Oppression the real problems
Technological optimists
Malthus was wrong, failed to account for scientific progress. Technology will solve all our problems
People are the ultimate resource. Growth rate will lead to technological solutions to our resource problems
We need to implement legislation to limit population growth
a network of relationships among a group of parts, elements, or components that interact with and influence one another through the exchange or energy, matter, and/or information
excess nutrients in the water which increase, which increase the production of organic matter, which depletes the oxygen
substances that cannot be broken down into simpler form by ordinary chemical reactions
revolve around the nucleus and bind one element to another
Determine the amount of protons
Extra electrons create electricity
Atoms electrically charged, due to gain or loss of electrons
are alternate versions of elements which differ in mass by having a different number of neutrons. Stable or radioactive
sharing of electrons- the more stable. Accumulate in fats
cations and anions- selfish relationship, less stable * Salt is ionic and water is ionic. Like dissolves like
Rock, sediment, soil below the earth’s surface
elements and compounds required in relatively large amounts: nitrogen, carbon, phosphorous
Nutrients needed in small amounts
Biogeochemical cycles
the movement (or cycling) of matter and energy through a system
Residence time
the average amount of time something spends in a reservoir
Residence time
the average amount of time something spends in a reservoir. Long residence time
CO2 cycle
So only about half of our anthropogenic CO2 stays in the atmosphere. It goes into plants, the ocean, and rocks
Phosphorous cycle
Comes from rocks. Weathering releases. Water soluble. One of the 2 most important nutrients for plants to have. Phosphorous has no stable gas phase, so addition of P to land is slow (low P in rain), and P is not well distributed. It can be transferred from the ocean to plants very effectively
Nitrogen cycle
Bacteria takes N2 out of the atmosphere and converts it into nitrates. Almost all is in the atmosphere.Today we are fixing as much nitrogen artificially as all bacteria do naturally. N20 a key greenhouse gas
The process where water goes from liquid to vapor through plants
Hydrologic cycle
Without more evaporation or transpiration, it cannot rain or snow- desertification (It’s a desert because there’s no plants there- plants keep the air with moisture). Warmer areas rain more. Rivers flow because there is more precipitation than evaporation
The rock cycle
The slow cycle of plate tectonics is what removes carbon from the atmosphere. Helps us find resources and tells us what we’re not likely to find
All organisms of the same kind that are genetically similar enough to breed in nature and produce live, fertile offspring
6 kindoms of life
1. Bacteria
4. Plantae
5. Fungi
6. Anamalia
4 conditions for evolution
1. Traits must vary within a population
2. Traits must affect reproductive success
3. Traits must be inheritable
4. External environmental pressure must favor
Law of competitive exclusion
no two species will occupy the same niche and compete for exactly the same resources for an extended period of time.
Allopatric isolation
Due to geographic separation
Sympatric isolation
Species doesn’t require separation. Occupy different niches
isolating mechanisms
1. Mechanical (structural difference)
2. Temporal (different timing for breeding)
3. Behavioral (differences in courtship)
4. Ecological
Direction selection
one trait is being favored and the other is being eliminated so the population shirts towards one trait. 1 new species
Stabilizing Selection
range of a trait is narrowed- no new spcies
Disruptive selection
traits diverge towards different ends- 2 new species
Intimate living together of members of two or more species
One member is benefited but neither is harmed
both members benefits
One member benefits at the expense of antoehr
Defensive mechanism (against predation and parasitism)
1. Massive numbers of offspring
2. Timing of activity
3. Location of habitat
4. Camouflage
5. Protecting young
6. Unpalatable body structure
7. Mimicry
Batesian Mimicry
Harmless species evolve characteristic to imitate poisonous or unpalatable species
Mullerian Mimicry
2 unpalatable species evolve to look like each other
number of species at each trophic level (where an organism is in the food chain), and the number of trophic levels, in a community
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