AP Environmental Science UNIT 5

Tragedy of the Commons

The tendency of a shared, limited resource to become depleted if it is not regulated in some way

Externalities

Negative costs associated with a human action, that aren’t accounted for in the price (unintended side - effects)

• Overfishing: fishery collapse (population crash) - loss of income and starvation

• Air pollution from coal power plants that leads to bronchitis, asthma, and increased healthcare costs

Solutions to the Tragedy of the Commons

• Private land ownership (individual or government owned)

• Fees or taxes for use

• Taxes, fines, criminal charges for pollution - shared air/soil/water resources

Bureau of Land Management

Grazing, Mining, Timber Harvesting, and Recreation

United States Forest Service

Timber Harvesting, Grazing, and Recreation

National Park Service

Recreation of Conservation

Fish and Wildlife Service

Wildlife Conservation, Hunting, and Recreation

Forest

A land area dominated by trees and other woody vegetation, sometimes used for commercial logging

• harvest by clear and selective cutting

Clear Cutting

The removal of all, or almost all, of the trees within the area. - Easiest and most economical method

Selective Cutting

Removes a single tree or a relatively small number of trees from the larger forest. Creates many small openings where trees can be reseeds or young trees can be planted which causes regenerated stand of trees for many different ages - harvests the largest trees

Reforestation

Areas where the same tree species are repeatedly planted, grown, and harvested

1st Agricultural Revolution

Early humans began to domesticate plants and animals

2nd Agricultural Revolution

Involving the mechanical side of farming (tools for plowing, planting, and harvesting) - movement of subsistence farming - consumption by the farming family

20th Century

Farming is more mechanized (fossil fuels), increases the food production industry

Green Revolution (3rd Agricultural Revolution)

Shift of agricultural production from small families to large industrial scale business - more machinery and less human labor - began with crop scientists developing strains of disease resistant wheat - increased use of fertilizers, pesticides, irrigation, GMOs, fossil fuels

Mechanization

Increased use of tractors for plowing and tilling fields, and combines for harvesting

Fertilizers

Growing crops and transporting them from the farm system to humans for consumption

Irrigation

Drawing water from the ground or nearby surface waters and distributing it on fields to increase plant growth

Pesticides

Substances that are either natural or synthetic, that kill or control organisms that people consider pests

GMOs (genetically modified organisms)

Genetically modified crops and animals offer possibility of greater yield and food quality, reduction in pesticide use, and higher profits for agribusiness that use them - increases crop yield, quantity, and increases profits

Monocropping

Growing a single crop species - decreases biodiversity, making crops more prone to pests and diseases due to a lack of natural predators

Synthetic (inorganic) Fertilizers

Runoff leads to water contamination and eutrophication (excess nutrients in waterways); requires significant fossil fuel energy for production; does not add organic matter to the soil

Saltwater Intrusion

Excessive pumping near coast lowers water table pressure, allowing saltwater to seep into groundwater

Cone of Depression

Forms when water table is lowered by excessive pumping, depleting water, and drying nearby wells

Furrow Irrigation

The farmer digs trenches along the crop rows and fill them with water - the water seeps into the ground/soil slowly and provides moisture to plant roots

Flood Irrigation

Involves flooding an entire field with the water and letting the water soak in evenly - more disruptive to plant growth than furrow irrigation

Spray Irrigation

Water is pumped into an apparatus that contains of spray nozzles that spray water across the field - more expensive than furrow or flood irrigation - more efficient and less water loss than flood or furrow

Drop Irrigation

A slowly dripping hose either on the ground or buried beneath the soil delivers water directly to the roots - most effective but most costly - reduces weed growth - avoids water logging and conserves water

Waterlogging

Overwatering can saturate the soil, filling all soil pore space with water - does not allow air into pores, so roots can’t take in the O2 they need

Fungicides

Specifically target fungi

Rodenticides

Specifically target rodents

Persistent Pesticides

Remain in the environment from years to decades - accumulates in the fatty tissue of animals

Non-Persistent Pesticides

Break down relatively rapidly - have fewer long-term effects - must be applied more often = overall environmental impact is not always lower than persistent pesticides

Integrated Pest Management (IPM)

Use of variety of techniques designed to minimize pesticide inputs - includes crop rotation and intercropping, the use of pest-resistant crop varieties, the creation of habitats for predators or pests, and limited use of pesticides

CAFOs (Concentrated Animal Feeding Operations)

Large indoor or outdoor structures designed for maximum occupancy of animals and maximum output of meat - beef cattle, dairy cattle, hogs, and poultry

Manure Lagoons

A large, human made pond lined with rubber to prevent the manure from leaking into the groundwater

Free Range Grazing

Allowing animals to graze outdoors on grass for most of all of their lifecycle without growth hormones - more sustainable meat production method

Overgrazing

Excessive grazing that can reduce or remove vegetation and erode and compact the soil

Desertification

Transformation of arable, productive, low precipitation land to desert or unproductive land due to climate change or destructive land such as overgrazing and logging

Nomadic Grazing

The feeding of herds of animals by moving them seasonally, productive feeding grounds, often over long distance (solution to overgrazing)

Fish Consumption Usage

Over 3 million people in the world with 20% of their animal protein (mostly Asia and Africa)

Fisheries

Populations of fish used for commercial farming

Surface Mining

Removal of overburden to access ore near the surface - open pit, strip, mountaintop removal, placer - removal of vegetation and soil, topsoil erosion, habitat loss, increased stream turbulence

Subsurface Mining

As ore near surface becomes more scarce, mining moves deeper underground to subsurface mining (more dangerous and expensive) - higher insurance and healthcare cost for workers - vertical shaft drilled down to transport (coal) - increasingly used as surface coal deposits are depleted

Strip Mining

Removal of overlaying vegetation and strips of soil and rock, called overburden to expose the underlying ore - used when the ore is close to earth’s surface - more susceptible to erosion

Mine Tailing

Unwanted waste material created during mining include material and other rock residues that are left behind the desired metals are removed from the ore

Mountaintop Removal

Miners remove the entire top of a mountain with explosives - large earth moving equipment removes the resources and deposits the tailing in lower revelation regions nearby

Open-Pit Mining

Creates a visible pit or hole close to the surface but extends beneath the surface both horizontally and vertically

Placer Mining

The process of looking for minerals, metals, and precious stones in river sediments (uses river water to separate heavier items)

Urbanization

The process of an area becoming more urban, increasing the density of people per unit area of land - removal of vegetation - prevents groundwater recharge, causing runoff

CO2 Emissions

Cement production, construction machinery, deforestation, landfills needed for disposing trash from large populations

Saltwater Intrusion

Excessive groundwater withdrawal near coast lowering water table pressure, allowing saltwater to seep into groundwater (caused by urbanization in coastal cities)

Suburbs

Less dense areas surrounding urban areas

Exurbs

Suburbs, but not connected to any central city or densely populated area

Urban Sprawl

Population movement out of dense, urban centers to less dense suburban areas surrounding the city

Ecological Footprint

Measure of how much a person/group consumes, expressed in area of land (gha - global hectare) - biologically productive hectare (2.47 acres)

Carbon Footprint

Measured in tones of CO2 produced per year

Sustainability

Consuming a resource or using a space in a way that does not deplete or degrade it for future generations

Urban Runoff

Rainwater or irrigation water that flows over impervious urban surfaces - such as sidewalks, roads, and rooftops - instead of soaking into the ground

Permeable Pavement

Designed to allow storm water to infiltrate and recharge ground water

Urban Systems

Urban systems that collect water (rain collection for city purposes, returned)

Build Up, Not Out

Building taller buildings so the footprint on the city surface stays the same - capacity to provide living and office space increases

Increased Planting and Public Transit

More cars on the road increases pollutants and trees store carbon

Biological Control (Biocontrol)

Introduces natural predators, parasites, or pathogens to manage pest populations

Intercropping

Planting diverse crops together to interrupt pest movement

Crop Rotation

Changing the type of crop grown in a field each season to balance nutrient use and disrupt pest cyces

Rotational Grazing

Moving livestock between different pastures in a planned way to allow vegetation time to rest and regrow, preventing overgrazing

Aquaculture

The farming of aquatic organisms such as fish, shellfish, and seaweeds

Open - Net Pens

Unsustainable method that floats in water offshore or near offshore - frame and netting that encloses the fish

Submerged - Net Pens

Sustainable method that is similar to open - net pens but the fish is completely submerged underwater

Pond Aquaculture

Sustainable method that uses open - net pens, but these pens are located in constructed or natural ponds on land

Recirculating Above - Ground Tanks

Sustainable method that can be located inside buildings or outdoors in almost any location as long as there is a suitable source of water for use inside the tanks

Sustainable Forestry

A methodology for managing forests so they provide wood while also provide clean water, maximum biodiversity, and maximum carbon sequestration in both trees and soil

Fire Suppression

The practice of putting out all natural forest fires as soon as they start - leads to more biomass buildup - worsens future fires - prevents fire damage and worse fires in the future

Prescribed Burn

When a fire is deliberately set under controlled conditions, thereby decreasing the accumulation of dead biomass on the forest floor - burns lots of biomass - uses biomass as fuel - susceptible for disease and pests - trapped nutrients stored in dead biomass - nutrients are recycled