Midterm Flashcards
Environmental Science
An interdisciplinary study of
1. How the earth (nature) works and has survived and thrived (ENST 210)
2. how humans interact with the environment (ENST 303)
3. how SHOULD humans interact with nature (ENST 395)
What does Grady assume?
- Humans have changed the environment in significant ways
- Science can describe many of these changes accurately
- Everyone has an interest in environmental protection:
- we disagree about the nature of environmental problems
- we disagree about the best solutions
Ecological Sustainability
Capacity of the earth’s natural systems that support life and human economic systems to survive or adapt to changing environmental conditions indefinitely
Sustainable Development
Meeting the current and future basic needs of its people in a just and equitable manner without compromising the ability of future generations to meet their basic needs
Triple Bottom Line of sustainability
Focusing on economic prosperity, environmental quality, and social justice
Calvin’s definition of sustainability
Sustainability emerges from choices that, on balance, promote economic vitality, social equity, and a flourishing natural environment both now and for generations to come
Ecological Principles of Sustainability
- Rely on Solar Energy
- Protect Biodiversity: genes, species, ecosystems, and ecosystem processes
- Protect Chemical Cycles: nutrient circulation
MEMORIZE THESE
Social Principles of Sustainability
- Politics: win-win results
- Economics: full-cost pricing
- Ethics: responsibility to future generations
Natural Capital
Types:
1. Inexhaustible (ex Sun)
2. Renewable (ex Trees)
3. Nonrenewable (ex Coal)
Sustainable living
Living off the earth’s natural income without depleting or degrading the natural capital that supplies it
Natural Capital & Sustained Yield
How much can you harvest now to continue to have that same harvest in perpetuity
- only take when there are plenty of plants and they’re healthy
- minimize harm, share what you’ve taken, and reciprocate the gift
- “take what is given to you”
Tragedy of the Commons
Prècis Breakdown
What is Science?
- Make an observation and identify a question
- Propose a hypothesis
- Test your hypothesis
- Gather data from your test
- Interpret your results
- Report for Peer Review
Correlation and Causation
Type 1 Error: False positive
Type 2 Error: False Negative
Myths of Science
- Provides proof/certainty
- Remains purely objective
- Limited only by the amount of data
Systems Thinking
A system is an interconnected set of elements that is coherently organized in a way that achieves something
- elements
- interconnectedness
- purpose of function
How to identify a system:
A) Can you identify parts
B) Do the parts affect each other
C) Do the parts together produce an effect that is different from the effect of each part on its own
D) (Usually) Does the effect, the behavior over time, persist in a variety of circumstances
How to influence a system:
Find the right leverage points
Five Axioms of Sustainability
- Any society that continues to use critical resources unsustainably will collapse
- Population growth / growth in rates of resource consumption cannot be sustained
- To be sustainable, the use of renewable resources must proceed at a rate that is less than or equal to the rate of natural replenishment
- To be sustainable, the use of nonrenewable resources must proceed at a rate that is declining, and the rate of decline must be greater than or equal to the rate of depletion
- Sustainability requires that substances introduced into the environment from human activities be minimized and rendered harmless to biosphere functions
Four Earth Systems:
- Atmosphere
- Hydrosphere
- Lithosphere (Geosphere)
- Biosphere
Atmosphere
Ozone layer, which filters out UV radiation
We evolved to see visible light–animals with night vision can see what we call UV light
Hydrosphere
Sublimation and evaporation put water in the atmosphere
1% freshwater, 2% icecaps, 97% oceans
Lithosphere
We’re mostly interested in the crust
Tectonic plates–convergent and divergent boundaries
Biosphere
Biosphere -> Ecosystem -> Community -> Population
Ecosystem
A set of organisms within a defined area…interacting with one another and with their nonliving environment of matter and energy
Life in an ecosystem is sustained by…
flows of matter and energy
Trophic levels
Producers -> Primary consumers -> secondary consumers -> tertiary consumers
Underneath are decomposers and detritus feeders
Productivity in ecosystems
Swamps and marches, tropical rainforest, temperate forest, taiga, savanna, agricultural land, woodland, temperate grassland, tundra, desert scrub, extreme desert
Chemical Cycles
SEE SLIDES
Climate:
Average weather
Key factors that determine climate:
- Uneven distribution of solar energy
- Rotation of the earth on its axis
- Properties of air, water, and land
Climate: Hadley Cells
0-60: Polar caps
60: temperate deciduous forest and grassland
60-30: Desert
30-0: Tropical deciduous forest
0: Tropical rainforest
Biome:
Large…regions, each characterized by a particular type of climate and a certain combination of dominant plant life
Terrestrial biome:
determined largely by precipitation and temperature
Marine biome:
Determined largely by light, temperature, and nutrients
Freshwater biomes:
determined largely by light, temperature, and nutrients
Oligotrophic and Eutrophic lakes
Oli: low in plant nutrients, high in oxygen in the deep parts
Eu: too many nutrients in the water–high plant growth uses up oxygen and marine animals die
Ecosystem Roles:
Native, nonnative, indicator, keystone
Evolution:
populations evolve when genes mutate and give some individuals genetic traits that enhance their abilities to survive and to produce offspring with these traits
Process of evolution:
- Genetic diversity and mutations
- Natural selection and adaptation (some die)
- Differential reproduction rates (survivors reproduce)
Speciation
Formation of new species
1. Geographic isolation
2. Reproductive isolation
Extinction & Extirpation
Extinction: gone over the whole world
Extirpation: gone in a local area
Keystone species
indicator species
K and R reproduction
Inertia vs Resilience:
Moderate vs severe effects
Ecological Inertia: ability of an ecosystem to survive moderate disturbances
Ecological Resilience: ability of an ecosystem to be restored (potentially drastic measures) after a severe disturbance
3 components (Cody):
Spirit, love, hope
