Land
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.
How does farmland become desertified?
Overgrazing, too many crops and land loses its fertility, soil erodes away, etc.
What is urban sprawl? Describe it.
Rapid expansion of a city into the countryside around the city creating suburbs.
What were the negative results of the green revolution?
Use of pesticides and fertilizers on large farms increased the risk of pollution.
What is deforestation? What is reforestation?
What are 3 negative impacts of deforestation?
Deforestation - The clearing of trees from an area without replacing them.
Reforestation - Replanting trees in an area. Growing a forest.
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 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.
List 3 modern agricultural methods.
Plowing with machines, irrigating with drip systems, and applying chemical fertilizers.
Where do most Americans live?
In what ways do people use land? List at least 3.
Urban areas - Suburbs.
Gathering resources (like wood), growing crops, building homes, creating recreation areas like parks, preserving native species, etc.
What is a persistent pesticide?
Becomes concentrated in organisms high on the food chain, does not break down into harmless chemicals, causes thin egg shells.
List 3 reasons why arable land is being reduced.
How are genetically engineered food crops viewed by scientists? Why?
Fast growing human populations, soil erosion, desertification.
Continue to be debated.
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 two major things drive farmers to cut down forests, 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 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
Integrated pest management includes what pest resistant methods?
Chemical pest control, biological pest control and a mix of farming methods.
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 is rangeland? What is it used for?
What can people do to improve rangeland? List 3 things.
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.
Eliminate invasive plants and replace them with native ones, leave land untouched so that it can recover, and raise smaller herds.
What is erosion? What are two human actions contribute to soil erosion?
Earthen materials are worn away and transported by natural forces such as wind or water.
Driving farming machinery over fields, constantly using soil thus degrading its quality, irrigation runoff.
List 3 factors that can cause famine. Why do many people around the world go hungry?
Failure of food production to keep up with population growth, distribution problems cause by political turmoil, and crop failure brought on by environment such as sustained drought.
Food production has not increased as quickly as the human population.
What is point source pollution? Provide two examples.
Why is groundwater pollution hard to clean? Give 3 reasons.
Pollution from a specific site. Ex - Waste entering water from a sewer pipe. Smokestacks. Factories and Power Plants. Drainage ditches.
Hard to reach deep groundwater. Time consuming. Pollutants can stick to materials in the aquifer.
How can we deal with the problem of seafood overharvesting? (First provide the test answer, then provide the real answer).
What are the impacts of overharvesting (not just seafood)?
Aquaculture – but not really, this is just what your outdated test asks for. The only actual ‘solution’ is to just stop eating them and let their severely depleted populations recover.
Collapse of food chains, economic collapse, and erosion of soil on land.
What percentage of all agricultural land is used by meat and dairy production?
What percentage of our current usable cropland is used for feeding livestock (so not considering the ~3/4ths of agricultural land being used for grazing)?
What percentage (or fraction) of pasture land used for grazing is unable to be converted to cropland for direct human use?
80% of all agricultural 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. Our current land usage for crops directly consumed by people is 704 million hectares.
Conclusion - We would have over 3x the cropland for growing food for people if we adopted vegan diets. The solution is not this simple, as that would be a LOT more water as well, but we already use water to grow crops for livestock on ~1/3 of that newly freed up land anyways, and these statistics are certainly interesting to consider when we look at hunger/starvation that exists in our current world.
How does no-till farming preserve soil quality?
How can a farmer reduce soil loss by erosion?
From where does irrigation water come from for most crops?
Remnants of previous crops are left to decay, fertilizing the soil.
By incorporating strips of vegetation inbetween plowed land.
Nearby rivers and groundwater.
What do people need to eat - What do we need to get to avoid malnutrition?
Where can we get this from? Do we need to eat meat?
What type of diet is shown to be the healthiest, leading to the most individuals that live 100+ years? What is the central theme of the diet?
Enough calories, and the 9 essential amino acids.
Food. No, we can get all 9 from plants.
Mediterranean diet - High in grains, beans, fruits, veggies, healthy fats (oils, nuts), and seafood.
All 9 are found in something like beans, and daily levels can be met with a reasonable intake of beans - 1 can puts you well over the daily requirements for everything other than methionine (which would be at around 67%), this can then be easily finished by eating something like nuts, pasta, etc.
While it is true you may want to think more about making sure you are meeting these levels as a vegetarian/vegan, it is so easy to do that it does not inconvenience your life at all whatsoever, and you probably accidentally meet the needs 99% of days if you eat a normal diet. On the other hand, if your diet is solely Doritos and mountain dew, then obviously you are more at risk of meeting these daily requirements (as well as everything else your body needs).
What is DDT? Why is DDT harmful to the environment?
It is a persistent chemical – does not break down into harmless chemicals, concentrates in the bodies of animals high on the food chain, and causes birds to lay eggs with thin shells so they break when birds sit on them.
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.