Resource utilization Flashcards
Slash and burn
An area of vegetation is cut down and burned before being planted with crops. Then, because soils in these developing countries are generally poor, the farmer must leave the area after a relatively short time and find another location to clear. This practice severely reduced the amount of available forest; it is a significant contributor to deforestation.
The green revolution
The time after the industrial revolution when farming became mechanized and crop yields in industrialized nations boomed
What caused the green revolution
Increase in the use of chemical fertilizers and pesticides
Advanced irrigation techniques
Introduction of genetically engineered plants (GMOs)
What are 3 downsides to the widespread use of chemical fertilizers?
They reduce organic matter and oxygen in soil.
Require large amounts of energy to produce, transport, and supply.
Are dangerous pollutants once they are washed into watersheds.
Federal insecticide, fungicide, and rodenticide act (FIFRA) of 1947 (amended in 1972)
Requires the EPA to approve the use of all pesticides in the United States
Problems of repeated irrigation
Salinization of the land (Significant buildup of salts on the soils surface that make the land unusable for crops)
To combat salinization, farmers have begun flooding fields with massive amounts of water to move the salt deeper into the soil. This large amount of water can Waterlog plant roots, which can kill the crops. This also causes the water table of the region to rise.
Integrated pest management
Tries to keep the pest population down to an economically viable level. Some of the methods include introducing natural insect predators to the area, intercropping, using mulch to control weeds, diversifying crops, crop rotation, releasing pheromone or hormone interrupters, using traps, and constructing barriers.
Beneficial example of genetically engineered plants
Golden rice, which contains vitamin A and iron
Problems that arise from genetically modified organisms (GMOs)
Discourage biodiversity, which may harm beneficial insects and organisms
Could pose new allergen risks
May increase antibiotic resistance
Could cause new pesticide resistant pests
Cross pollination can contaminate other crops or cause unwanted mutations with unknown results
Photosynthate
Photosynthetic products
Contour plowing
Rows of crops are plowed across the hillside, preventing the erosion that occur when does are cut up and down on a slope.
Terracing
Aids in preventing soil erosion on steep slopes. Terraces are flat platforms that are cut into the hillside to provide a level planting surface; this reduces the soil runoff from the slope.
No-till methods
Farmers plant seeds without using a plow to turn the soil. Soil loses most of its carbon content during plowing, which releases carbon dioxide gas into the atmosphere
Crop rotation
Can provide soils with nutrients when legumes are part of the cycle of crops in an area.
Intercropping (strip cropping)
The practice of planting bands of different crops across a hillside. Can prevent some erosion by creating an extensive network of roots which hold the soil in place and reduce or prevent soil erosion
Overgrazing
Grass is consumed by animals at a faster rate than it can regrow. It is harmful to the soil because it leads to erosion and soil compaction
Solutions to overgrazing
Animals can be rotated from site to site and away from their source of water
Overall control of herd numbers
Silviculture
The management of forest plantations for the purpose of harvesting timber
Shelter-wood cutting
A type of uneven-aged management in which mature trees are cut over a period of time (usually 10-20 years); this leaves some mature trees in place to reseed the forest
Agroforestry
Trees and crops are planted together to create a mutualistic symbiotic relationship between the trees and crops - the trees create habitats for animals that prey upon the pests that harm crops, and their roots also stabilize and enrich the soil
Wilderness Act of 1964
Established a review of road-free areas of 5,000 acres or more and islands within the National Wildlife Refuges or the National Park System for inclusion on the National Preservation System. This act restricted activities in these areas.
Wild and Scenic Rivers Act of 1968
Established a National Wild and Scenic Rivers System for the protection of rivers with important scenic, recreational, fish and wildlife, and other values
greenbelts
Open or forested areas built at the outer edge of a city. Since no one is permitted to build in them, they can increase the quality of life for people living nearby. They also border cities, putting limits on their growth.
Surface fires
Typically burn only the forests underbrush and do little damage to mature trees. These fires actually serve to protect the forest from more harmful fires by removing underbrush and dead materials that would burn quickly at high temperatures, escalating more severe fires
