AP Environmental Science Unit 5
Abundance of Ores and Metals
Crustal Abundance
-The average concentration of an element in Earth’s crust.
-The concentration of the crust changes when you move mining locations.
Ore
-A concentrated accumulation of mneras from which econoicallt valuable materials can be extracted.
-Characterized by the presense of valubale metals, but salt and sand can also be considered ores.
Metal
-An element with proporties that allows it to conduct electricity and heat energy, and to perform other important functions.
-Copper, nickel, and aluminum are good examles of metals, similar to concentrations such as sulfur, oxygen and silicon, which all exist within rock.
Reserve
-The known quantity of a resource that can be economically recovered.
Mining Techniques
Strip Mining
-The removal of strips of soil and rock to expose ore
-Used when the ore is close to earths surface, usually coal or sand
-Use the removed mining spoils or tailings to the hole created.
Mining Spoil/Tailing
-Unwanted waste material created during mining, also known as tailings.
Open-pit Mining
-A mining technique that uses a large visibile pot or hole in the ground.
-Used when the resource is close to earths surface.
-Most commonly copper mines.
Mountaintop Removal
-A mining technique in which the entire top of a mountain is removed with explosives.
-Requires lots of heavy duy equipment, including oving equipment.
-Deposits talings in lower elevation regions, often in streams or rivers.
-Significant dust formed from earth-moving equipment
-Contamination f water that percolates through tailings.
-Most soil removed fom site; may be replacced if reclamation occurs.
-Habitat alteraion and destruction over the surface ares that are mined.
Placer Mining
-The process of looking for minerals, metals, and precious stones in river sediments.
-Miners use the river water to seperate heavier items, such as diamonds, tantlam and gold from lighter items such as sand and mud.
-Used during the gold rush in the mid 1800s.
Subsurface Mining
-Mining techniques used when the desired resource is more than 328 feet (100 meters) below the surface of the Earth.
-Usally a verticel mine that requires an elevator.
-Used to mine diamonds, coal and gold.
-Minimal dut buildup, but lots of emmioons from fossil fuels used go power mining equipment.
-Acid mine drainage as well as contamination of water that percolates through tailings.
-Road construction to mund fragments habitat.
-Possibility of death, or chronic respritory illnesses such as black lung disease.
Mining Safety and Legislation
Disease
-The inhalation of fumes from subsurface mining can cause black lung disease, and asbestos poisoning.
Injury
-More than 11,000 miners died in mine explosions between 1900 and 2006.
-The United States has restricted subsurface mining because of the risk involved. Countries like China have more accidents because they still use the subsurface mining technique.
Laws
-The mining law of 1872 focused on the mining of silver, copper snd gold ores as well as fuels including natrual gas and oil on federal land. This law was created to encourage settlement in the west.
-The surface mining control and reclamation act of 1977 regulates subsurface mining of coal and surface effects of subsurface coal mining. The act insures that land be minimally disturbed during the mining process and reclaimed after mining is complete.
Urbanization
Impervious Surface
-A surface like concrete that is unable to infiltrate water
-Creates run-off
CO2 Emission
-Increased in cities by cement production, construction machnery, desforestation and landfills.
Urbanization in Costal Cities
-Excessive groundwater withdral nearthe coast lowering water table pressure, allowing saltwater to seep into groundwater. (Saltwater Intrusion)
-Sea level rise due to warmng of ocean and the melting of ice caps, can contaminae groundwater with salt.
Trends in Population
-Many nations moving away from rural farm life and into city life.
-Some nations doing the opposite and moving from city life into rural life.
-Urban areas decrease the amount f transportation needed per person, decrease enviornmental impact.
-Population growth is highest in suburban areas.
Urban Sprawl
-Cheaper property in the suburbs.
-Cars make it easier to get around, especailly to work.
-Domino effect makes people move because of influence.
-Fewer residents in cities leads to decline in tax revenue in the city
-Abandoned homes create blights, rundown infrastructure
-Caused by the increase in highway expansion
-Can be solved by Urban Growth Boundaries, zoning laws that are set by cities preventing development beyond a certain boundary. Also, Mixed Land Use, residential, business, and entertainment buildings all located in the same area of a city.
Urban Runoff
-Decreased infiltration (groundwater recharge)
-Rain washes pollutants into strorm drains an into local surface waters.
-Salt, seditment, fertilizer, pesticides, oil and gas are all pollutants that are in urban runoff
Solution 1 Permeable Pavement
-Decreases runoff, decreasing pollutants carried into storm drains
-Decreases flooding.
-More costly
Solution 2 Rain Garden
-Creates habitat for pollinators and stores CO2.
Solution 3 Public Transit
-More cars on the road=more pollutants on the streets to runoff into storm drains and local waters.
-Public transit decreases urbam runoff, pollutants on the road, and CO2 emissions
-Less traffic.
Forestry
Clear Cutting
-A method of harvesting trees that involves removing all of the trees within an area.
-When replanted, all trees will be the same age.
-Reduction of biodiversity.
-Increase wind and soil erosion.
-Ideal for growth because of direct sunlight.
-Dangerous mudslides.
-Increases tempature because of direct sun.
-Heavy equipment.
Selective Cutting
-The method of harvesting trees that involves the removal of single trees or a relitively small number of trees amoung many in a forest.
-Different aged trees.
-Optimum growth for shade-tolerant trees.
-Less environmental impact.
-Heavy equipment.
Ecologically Sustainable Forestry
-An approach to removing trees from forests in ways that do not negatively affect the viabiliy of other trees.
-Maintains both plants and animals in a natural state.
-Makes less money.
Tree Plantation
-A large area typically planted with a single rapidly growing tree species.
-Same aged trees.
-Do not grow into diverse forests.
-Soil can become depleted because of frequent replanting.
Prescribed Burn
-A fire deliberately set under controlled conditions in order to reduce the accumulation of dead biomass on a forest floor.
-Decreases the frequency of natural forest fires.
Human Nutritional Needs
Primary Plants - Wheat, corn, rice
Primary Animals- Beef, pork, chicken
Malnourishment
-Lacking balance of calories and nutrients.
-Developmental issues and a higher risk of cancer.
Undernourishment
-Lacking Calories.
-Causes low energy and reduced physcial and mental capabilities.
Overnutrition
-Too many calories
-Can cause heart problems and diabetes.
Agriculuture
Industrilized Agriculture
-Uses large amounts of fuel, water, fertilizers and pesticides.
-80% of our food supply.
Traditional Agriculture
-Less technology, fertilizers and pesticides.
-Usually grown for one family, not for a corporation.
1st Green Revolution (1950 to 1970)
-Increased crop yield per area of land in developed countries by implementing:
-Selective breeding
-Pesticides
-Fertilizers
-Irrigation
-Better equipment
-Multiple cropping
-Increase in intensity and multiude of farming
2nd Green Revolution
-Came in developing countries around 1970 with the introduction of fast growing crops.
Food production in the U.S
-Production has doubled since 1940
-Corporate farming has replaced smaller family farms
Cost of increased production
-More energy is used than created for most crops (especailly meat)
-The energy requires shipping and processing
-Industrilized agriculture requires 10 units of energy to make 1 unit of product
-Traditional agriculture requires 1 unit of energy to make 10 units of product.
Salinization
-Irrigation water contains salt when the water gets evaporated the salt gets left behind.
Waterlogging
-When soil is too saturated and can’t drain.
Types of pesticides
-Can be either organic or synthetic
Broad spectrum pesticides
-Kills a wide variety of bug species including target species and beneficial insects.
Selective pesticides
-Is designed to harm only target pests, minimizes harm to other benefical organisms.
Persistent pesticides
-Remains for a long time
-Prolonged toxcity affects other species
-Don’t have to apply as often
-Can lead to bioaccumulation and biomagnification
Non persistent pesticides
-Have to apply more often
-Breaks down in a few weeks or months
Biomagnification
-The process as described when toxic substances increase in concentrations as they continue through a food chain.
Pesticides Pros and Cons
-Less labor needed to kill harmful species.
-Controls diseases caused by pests.
-Newer pestices are not as harmful for the environment.
-Toxins accumulate in food chains
-Threatens endangered species
-Small amount of success (5%)
Pesticide treadmill
-The cycle in which farmers go through in order to make sure pesticides work.
-Farmers have to constantly apply pesticdes because of the low success rate.
Genetic Engineered Crops (GMO)
-Crops that are modified to be more resistant against disease and pests.
-Large debate over possible health impacts.
Concentrated Animal Feeding Operations (CAFOs)
-An agricultural practice in which animals are confined in one area and fed constantly
-Most livestock comes from CAFOs
-Minimizes land and energy usage
-Improves feeding efficiency
Cons to CAFOs
-Tons of waste with poor management
-Desertification
-Erosion
-Water pollution from runoff
-Large onnection to global warming (Methane and Nitrous Oxide)
Aquaculture (Blue revolution)
-The cultivation (breeding) of underwater animals
-Very efficient and produces a lot of stock in small volumes of water.
-Requires large amounts of land, feed, water and energy.
-Creates lots of waste and runoff.
Whats happening
-The creation of better technology has created a high demand for fish.
Ex: Sushi
-Aqua culture has caused mass extintion amoung seabass, and the tooth fish
-Responsible for the creation of fisheries and fish farms
-High pollution of coastal areas
-Habitat degradation.
Alternatives to Industrial Farming Methods
Slash and burn
-The cutting and buring of trees to prepare the desired land for agriculture. Creates deforestation and increaseed carbon emissions.
Nomadic Grazing
-Free range animals
Desertification
-Fertile land becomes dry and loses productivity through the use of excessive agriculture.
Intercropping
-Growing two or more crops in the same field at the same time.
-Increases nutrients and the soil and prevents erosion.
Crop rotation
-Growing different crops in the same area over multiple growing seasons
-Helps to replace missing nutrients and to allows soil to recover.
Agroforestry
-Growing trees and crops along with crops and animals
-Vegetation of different heights reduces erosion
Contour plowing
-Planting following the curves of the land
-Slows erosion
Terracing
-Cutting flat areas into sloped land (like steps)
-Slows erosion
Preventing Soil Degradation
No till agriculture
-Planting crops without disrupting the soil.
-Leaving old crops on soil instead of plowing, this can provude cover for new plants while they grow.
-Increases crop yield and carbon content, while decreasing water and pesticide use.
Integrated Pest Management (IPM)
-Pest control using a variety of strategies
-Sustainability, economics, integration, practicality
Pros
-Reduced contamination and degradation of the environment
-Cancer causing residues are present in smaller amounts or are not on food at all
Cons
-Takes a long amount of time, must be a year-round program and multiple crop inspections are requried to check effectiveness
-Some parts of the IPM method can cause damage to the crops
Free range meat
-Less disease
-Less antibiotics
-Less supplemental feeding
-Natural processing of waste
-Costs more
CAFO meat
-Increased land use
-Worse land and animal conditions
-Bad waste disposal
-Requires more feed
-More antibiotics
Organic Agriculture
-Minimal use of pesticides, aviods synthetics
-No antibiotics or growth hormones
-No GMOs
-May be small family farm or large agribuisness
USDA Organic
-If an agricultual product is labeled organic that means it contains 95% or more organic material.
-The organic label does not guarantee a small family buisness, a local source, humane pracices, free range, worker safey or fair worker conditions.