Environmental Impact
What is deforestation? What is reforestation?
Deforestation - The clearing of trees from an area without replacing them.
Reforestation - Replanting trees in an area. Growing a forest.
What is cropland? What is it used for? Why is this important?
Land with the right soil that can be used for growing crops.
Main purpose is to grow crops for food (human and livestock), fuel, fiber.
Importance: Oxygen source. Temperature moderator.
What is urban sprawl? Describe it.
Rapid expansion of a city into the countryside around the city creating suburbs.
Where do most Americans live?
Urban areas - Suburbs.
How many layers does Earth have? What are their names?
4
Crust, Mantle, Outer Core, Inner Core
What are 3 negative impacts of deforestation?
Habitat destruction, loss of flood control / protection, erosion and loss of topsoil, loss of temperature regulation, loss of carbon sequestration (plants capturing and storing atmospheric CO2).
What is rangeland? What is it used for?
Land that support different vegetative types like grasslands, shrublands, deserts, and land that is not used for farming or timber production.
Most common use for rangeland is grazing by livestock.
What is urban crisis? What are 3 issues associated with living in an urban area?
When urban areas grow so rapidly, they run into trouble such as: Traffic jams, Substandard housing, Polluted air, Polluted water, Loss of farmland
In what ways do people use land? List at least 3.
Gathering resources (like wood), growing crops, building homes, creating recreation areas like parks, preserving native species, etc.
What is a divergent boundary? What does it typically cause?
Two plates are moving in opposite directions as in a mid-ocean ridge.
Creates ridges, trenches, etc.
What are the four greenhouse gases we have mentioned in this class? What is one example of how each greenhouse gas would be released into the atmosphere?
Water Vapor - Water evaporating.
Carbon Dioxide - Burning fossil fuels.
Methane - Cow burps / farts, melting permafrost.
CFCs - Aerosol cans.
What is wilderness? What are two major threats to areas that are being protected?
Main purpose is that the land and ecosystems it supports are protected from all exploitation.
Population growth and tourism - more visitors, more visitors not practicing proper etiquette when visiting parks, climate change.
Why is rural land important? Why is it better for the environment than a concrete jungle? Provide at least 3 reasons.
Air purification, soil renewal, climate regulation, biodiversity, nutrient cycling, etc.
What can people do to improve rangeland? List 3 things.
Eliminate invasive plants and replace them with native ones, leave land untouched so that it can recover, and raise smaller herds.
What is a convergent boundary? What does it typically cause?
Two plates collide to form mountains or a subduction zone.
What is the difference between clear cutting and selective cutting? Which one is better for the environment?
Clear-cutting is the process of removing all of the trees from an area of land. Selective cutting is the process of cutting and removing only middle-aged or mature trees. Selective cutting minimizes the impact on forest ecosystems.
What are 3 benefits of forest preserves and parks?
Benefits of open spaces / parks in cities:
Improvement of air quality due to filtration of pollutants by plants. Flood control. Temperature regulation (keeps cities cooler in summer). Recreation space.
What (or who) is the largest producer of primary air pollutants in the US? Why does this result in so much pollution - what are they doing? How could this pollution be reduced?
The largest producer of primary air pollutants in the US is the energy industry – generating electricity.
Burning fossil fuels to generate energy.
Using green methods of generating electricity, such as solar, hydropower, geothermal, wind, nuclear, etc.
What two major things drive farmers to cut down forests in developing countries, excluding collecting wood?
(Why is this pretty ironic?)
More land for growing crops.
Search for better soil as soil quality decreases.
The more forest that is cut away, the more topsoil erodes and soil quality decreases, causing them to have to search further and cut down more trees. A much more obvious solution would be to cycle their crops, and preserve local ecosystems to maintain soil quality.
What is a transform boundary? What does it typically cause?
Two plates are sliding past each other as in the San Andreas fault of California. A transform boundary is like a tear in the Earth's crust. These plates move very slowly across the surface of the Earth as though they were on a conveyor belt.
What are six major consequences that our planet faces as a result of a rising global temperature?
Melting ice caps and glaciers.
Rising sea levels.
Spread of disease and release of preexisting diseases.
More frequent and severe storms, droughts, heatwaves.
Warming oceans, more acidic oceans.
Loss of biodiversity.
What percentage of all agricultural land is used by meat and dairy production?
What percentage of our current usable cropland is used for growing food to feed livestock?
What percentage (or fraction) of pasture land used for grazing is UNABLE to be converted to cropland for direct human use?
80% of all land.
43% of our cropland is used to create feed for livestock.
65% (2/3) of pasture land - Meaning that although we cannot use all of that land directly for crops / veggie diets, we can free up 1/3 directly towards growing crops... remember that pasture land makes up about ~70% of ALL land usage (2.9 billion hectares)... meaning that 1/3 of that land would be the equivalent of 967 million hectares of land freed up from pasturelands, on top of the 538 million hectares of land freed up from cropland used for animal feed. This brings us to a total of 1.5 billion hectares of land directly freed up to be used for growing crops, if we should so please.
What part of the atmosphere is the ozone layer located in?
What were we releasing that was damaging the ozone layer? How have we started to repair the ozone layer?
Why is the ozone layer important (what does it do for you)?
Stratosphere
CFCs - Chlorofluorocarbons
Lies high up in the atmosphere and shields us from harmful ultraviolet (UV) rays that come from the sun. Contains a high concentration of ozone in relation to the rest of the atmosphere.
Why are people wrong when they say our current climate trends are "natural" and "normal"?
Our current climate change trends are drastically more rapid than any previous climate period in all of history, and by a long shot. Rather than taking tens of millions to see a ~10-15 degree shift in global temperatures, we are estimated to see a ~10 degree shift in about 250 years.
Using these stats / predictions from our notes / graphic that I shared with you, this means we are raising global temperatures about 240,000 times faster than our most recent "natural" global temperature change in the past.
What is a subduction zone? How would a subduction zone be caused? What can subduction zones lead to / cause?
Subduction Zone - A boundary in which an oceanic plate is driven down and destroyed by a continental plate.
Cause increased amounts of earthquakes, tsunamis, volcanic eruptions, etc.