Tragedy of the Commons (TOC)
people overusing public/common resources because they do not experience the negative effects
Examples of TOC
overgrazing
overfishing
water and air polution
overuse of groundwater
public bathrooms
Why does the TOC occur
nobody suffers the consequences
assume others will overuse if they dont
no penalty
What is the problem with TOC
depletion of resource altogether
harmful effects
extternalities
cost that comes with a human activity, but the human doing that activity does not feel the effects
How to solve TOC
private land ownership
fees or taxes for use
taxes, fines, criminal charges for pollution or shared air/soil/water resources
Clearcutting
The process of cutting down all the trees in an area at once usually for lumber or to use the land for something else
economically advantageous
negatively effects the forest
Direct Effects of Clearcutting
Soil Erosion
loss of stabilizing root structure
no more org. matter and nutrients
sediments go into streams > turbid (cloudy) waters Increased soil and stream temp
lose of shade
soil absorbs more sunlight (low albedo)
loss of tree shade warms water
erosion of sediments into rivers and warms them
dries out soil (more erosion) Flooding and Landslides
no stabilizing root structure, more erosion
increased sublight dries soil logging machinery compacts soil > decrease H2O holding capacity causing flooding and landslides without trees roots
Tree plantations
areas where the same tree species are repeatedly planted, grown, and harvested
lowers biodiversity > lower resistance
trees all the same age > no dead trees - organisms need it like woodpeckers, insects, and decomposers
Forest Benefits
Filtering of Air Pollutants
Leaf pores (stomata) remove VOCs, NO2, PM from air and store in tree CO2 storage
take carbon dioxide and release O2, less CO2 in atm. Habitat for organisms
tourism, many organisms live in forests, biodiversity
deforestation consequences
reduces air filtering and carbon storing
releases CO2 from decomosition of leftover org material (stumpts)
slash and burn
method of clearing land for agriculture by cutting trees and burning them releases CO2, N2O and water vapor into atm (all Green House Gases)
Green Revolution
A shift in new agricultural strategies and practices in order to increase food production, with both positive and negative results. Some of these strategies and methods are mechanization, genetically modified organisms (GMOs), fertilization, irrigation, and the use of pesticides
shift from small, family owned farms to large industrial scale agribusiness
advantages of the Green Revolution
increased efficiency of lands, short-term profitability, and food supply
decreased world hunger and increased earth's carrying capacity for humans
negatives to the Green Revolution
soil erosion
biodiversity loss
contamination of ground and surface waters
mechanization
use of machines to do agricultural labor
increased use of tractors for plowing and tiling fields, and combines for harvesting = increased yield + profits
negatives
uses fossil fuels
climate change
soil erosions
compact soil, does not hold water
High Yield Variety Crops
hybrid, or genetically modified crops that produce a higher yield (amount fo crop produced per unit of area) advantages
increased yield and food stability in regions previously prone to famine (India, Pakistan, Mexico)
hybrid
cross pollinating different species, or parent plants with ideal traits
GMOS
Organisms that have been geneticly altered to improve their usefulnes
genes giving them advantageous traits
increases profiability with fewer plants lost to drought, disease, or pests + larger plant size + yield/acre
no genetic diversity, vulnerable to disease
synthetic fertilizer
manmade synthetic chemicals like ammonium, nitrate, and phosphate
increases yield and profits with more key nutrients needed for plant growth (N,P, K)
excess nutrients washing into water causing eutrophication
fossil fuels -> climate change
irrigation
drawing water from the ground or nearby surface waters and distributing it on fields to increase plant growth
make agriculture possible where it is too dry
can deplete aquifers and groundwater sources
overwatering -> water logging
soil salinization
Pesticides
increase in use of synthetic pesticides - chemicals sprayed on crops that kill weeds, insects, rodents, and other pests that eat or damage crops
increases yield and profits with fewer plants lost to pests
can wash off crops in runoff and kill or harm non targe species (bees especially)
DDT (dichlorodiphenyltrichloroethane)
is a pesticide that was widely used in the mid-20th century. It was effective in controlling a variety of insects, including those that spread diseases like malaria. However, it was later discovered that DDT was also highly toxic to wildlife and persisted in the environment for long periods of time. As a result, its use was banned in many countries, including the United States, in the 1970s. Despite the ban, DDT can still be found in the environment today, and it continues to be a controversial issue.
Monocropping
growing one single species of crop
highly efficient for harvest, pesticide and fertilizer application
greatly decreases biodiversity
increases soil erosion (b/c harvested all at once)
no habitat diversity for species in the area
tilling
mixing and breaking up soil to make planting easier
loosens soil for roots
erosions
loss of root structure
loss of org matter topsoil from erosions
Particulate matter, particles in air and water (turbid water)
slash and burn agriculture
cutting down vegetation and burning it to clear land for agriculture and return nutrients in plants to soil
deforestation
loss of habitat, biodiversity, CO2 storage, loss of air pollution filtration
releases GHS leading to global warming
particulate matter
lower albedo, increases temp, dry out area
Synthetic/ Inorganic Fertilizers
do not return org. matter to soil; no increased H2O holding capacity and no soil decomposers
leaching
Leaching
water carries excess nutrients into groundwater or into surface waters
contaminates groundwater for drinking
causes eutrophication
furrow irrigation
trench dug along crops and filled with water
easy, inexpensive
33% evap runoff
minecraft farms
flood irrigation
waterlogging
flood field -25% runoff evap afalafa
spray irrgation
expensive, efficient
20% to runoff and evap
fossil fuel
need lots of equipment
drip irrigation
costly, efficient
5% lost to evap and runoff
holes in hose allow slow drip of water
water logging
overwatering filling all soil pores, no O2 can go into it
stunt plant growth or kill crops solution - drip, soil aeration
soil aeration
poking holes or cores in soil to allow air in and water to drain through soil
soil salinization
salt building up in soil over time b/c groundwater has salt
water evaps and salt is left behind
dehydrates plant roots solutions
soil aeration, flush wish fresh water, fresh water sources, drip irrigation
global human use
agriculture - 70% municipal - 11% industrial - 19%
Groundwater
H2O stored in pore space of permeable rock and sediment layers
Aquifers
usable groundwater deposits for human
groundwater recharge
rain water percolating down through soil into aquifer
unconfined aquifer
an aquifer made of porous rock covered by soil out of which water can easily flow
confined aquifer
an aquifer surrounded by a layer of impermeable rock or clay that impedes water flow
Pesticides
Chemicals that are toxic to pests
different types for different pests
Can cause pests to become resistant to pesticide with over use
genetic biodiversity gives some pests resistant traits to pesticide
Pesticide artificially selects for pests with resistance by killing all the non-resistant individuals leaving only resistant ones
pesticide treadmill
A cycle of pesticide development, followed by pest resistance, followed by new pesticide development
GMOS
Gene for pest resistant trait is added to the plant through genetic modification
BT corn with bacteria gene that produces Bt toxic pests
GMOs and Pesticide Use
Bt corn has decrease insecticide use, since corn makes its own insecticide
Round up ready crops have increased b/c crops cannot be harmed by the pesticide
GMOs and genetic Diversity
no diversity
if disease or pest, they do not have any chance of any genetic mutation or adaptation b/c they are all the same
none will survive
CAFOs
Concentrated Animal Feeding Operations
feedlocks densley crowded method where animals are fed grain to raise them quickly
advantages of CAFOs
minimizes cost of meat for consumers -maximizes land use and profit
disadvantages of CAFOs
-given antibiotics and growth hormones to prevent disease and speed meat production
animals produce large volume of waste which can contaminate nearby surface or groundwater
green house gases
Manure Lagoons
large, open storage pits for animal waste
waste contrains: ammonia (N), hormones, antibiotics, fecal coliform bacteria (e.coli)
heavy rain can flood, contaminate these pollutants into surgace and ground water
causing eutrofication
ecoli
antibiotics and growth hormones alter humans -denitrification of ammonia in manure produces N2O (GHG!!!!)
solution: can be emptied and buried in landfills, or turned into fertilizer pellets
Free Range Grazing
animals graze on grass and grow at a natural rate without growth hormones
free range grazing advantages
no need for antibiotics, or corn waste is dispersed acting as fertilizer instead of building up in lagoons
animals can graze on land too dry for crop growth
Overgrazing
too many animals eat too much of the plant cover and impedes plant regrowth
erosion animals cna compact soil, decreasing H2O holding capacity -. more erosion
desertification if plants are killed by overgrazing and soil is compacted so much that it can't hold enough water anymore
Desertification
Degradation of land, especially in semiarid areas, primarily because of human actions like excessive crop planting, animal grazing, and tree cutting.
solution to overgrazing
rotational grazing (moving animals periodically) can prevent over grazing
can increase growth of grass by distributing manure and clipping grass back to size where growth is most rapid
Inefficiency of Meat
producing meat for humans to eat is far less efficent than producing plants in terms of energy, land and water use
energy
all the energy needed to plant, grow, harvest plants to feed to animals PLUS
energy needed to
bring water to animals
energy needed to house animals
energy needed to slaughter and package
land
all of the energy needed to grow plants to feed animals PLUS the room animals take up
water
all of the water for crops that animals eat plus the water animals drink
fisheries
populations of fish used for commercial fishing
fishery collapse
when overfishing causes 90% population decline in a fishery
population may never recover from fishery collapse b/c of decreased biodiversity, inability to find mates, inbreeding depression
decreases genetic biodiversity of fish populations and species biodiversity of ocean ecosystems if species are lost from ecosystem economic consequences: loss of income, lost of tourism money
Bottom Trawling
Especially harmful fishing method that involves dragging a large net along ocean floor bycatch more turbid, destroys coral reef structure decreases biodiversity by killing non target species and removing coral reef habitat
bycatch
The unintentional catch of nontarget species while fishing
Ore
commercially valuable deposits of concentrated minerals
metals
elements that conduct electricity, are shiny, heat well and are easily shaped, solid at room temperature (except mercury) (found within ores)
made steel
reserve
known amount of resource left that can be mined
usually measured in years left of extraction
overburden
soil, vegetation and rocks that are removed to get to an ore deposit below
Tailings and Slag
leftover waste material separated from the valuable metal or mineral within ore
Open put mining
dig a big pit and mine from sides
placer mining
shaking out sediments
strip mining
the removal of strips of soil and rock to expose ore
mountain top removal mining
entire mountaintops are blasted off, economically efficient. Used for coal
negatives to surface mining
removal of vegetation and soil
topsoil erosion
habitat loss
increased stream turb
increase PM in air
Why to do subsurface mining
surface becomes more scarce
subsurface mining
more expensive b/c of higher insurance and health care costs for workers
risks: poor ventiliation, leading to toxic gas exposure, mine shaft collapse, injury from falling rock, lung cancer, asbestos, fires, explotions
vertical shaft drilled down into crowned
elevator to transport workers and the resource
coal
increased use
acid mine drainage
rainwater leaks into abandomed mine tunnels and mizes with pyrite making sulfuric acid
rainwater carrier sulfuric acid into nearby streams, or infiltrates ground water
lower pH of water making toxic metals more soluble
methane release
coal mining releases methane gas from rock around coal
vented out of mine to prevent explosion and continues seeping out after mine closes -GHG -> climate change
PM release
coal mining especially, releases lots of soot that can irritate human and animal lungs
Mine reclamation
the process of restoring land that has been mined to a natural or economically usable state
fill hole
restore contours of land
return topsoil, remove bad stuff
replanting of native plants, resorting community
Urbanization
removal of vegetation and conversion to city
replaces soil, vegetation, wetlands, with impervious surfaces which dont allow water to infiltrate into the ground
CO2 emissions for the process -urbanization prevents groundwater recharge
Saltwater intrusion
an infiltration of salt water in an area where groundwater pressure has been reduced from extensive drilling of wells
Excessive groundwater withdrawal
near coast lowering water table pressure, allowing saltwater to seep into groundwater
sea level rise
due to warming of ocean and melting of ice caps can contaminate fresh groundwater with salt
urban sprawl
The process of urban areas expanding outwards, usually in the form of suburbs, and developing over fertile agricultural land.
b/c cheaper to live in suburbs
b/c cars easy transportation into city
everyone else leaving domino effect
fewer residents in cities leads to decline in tax revenue for city, decreases in city services
more residents leave, so business follow
blight (rundown)
solutions to urban sprawl causes: urban growth boundaries
zoning laws set by cities preventing development beyond a certain boundary
solutions to urban sprawl causes: mixed land use
residential, business, and entertainment buildings all located in the same area of a city -enables walkability and sense of place
Ecological Footprint
Total amount of land taken up by the consumption of an individual or a group
Factors of Ecological Footprint
food production
raw materials
housing
electricity production
waste
Differences between Ecological Footprint and Carbon Footprint
EF: global hectares or acres CF: tonnes
carbon footprint
the total carbon dioxide emissions produced by an individual, group, or location
all CO2 released from an individual or groups consumption and activities
material goods
food production
energy use
Factors that affect Footprint
INCREASE how wealthy you are
larger houses
more travel
more resources needed for material goods meat consumption fossil fuel usage DECREASE
renewable energy use
public transportation
plant based diet
less consumption, less travel, less energy use
Earths
5.1 earths is average currently using 1.85 earth- unsistainable
Sustainability
consuming a resource or using a space in a way that does not deplete or degrade it for future generations
maximum sustainable yield
the maximum rate at which a renewable resource can be exploited without impairing its ability to be renewed or replenished
Environmental indicators of sustainability
Factors that help us determine the health of the environment and guide us towards sustainable use of earth's resources
biodiversity = high= healthier
declining biodiv can indicate pollution, habitat descrution, climate change
global extinction rate
food production
indicates ability of earth's soil, water, and climate to support agriculture
major threats = climate change, soil degradtion, ground water depletion
meat consumption further strains on food prod
global grain production per capita has leveled off and sown signs of decline recently
Atmosphereic Temp and CO2 global indicator
-life on earth depends on very narrow temperature range
CO2 is a GHG
increased CO2 = increased temp
deforestation increase atm CO2
increasing CO2 = unsustainable
human population and resource depletion
as human pop grows resource depletion grows
harvest resources at unsustainable rate
Urban Runoff
Storm water runoff
env. consequences of urban runoff
decreased infiltration (groundwater recharge) b/c impermeable surfaces
rain washes pollutants into storm drains and into local surface waters Pollutants and effects
salt (death)
sediment (turbid)
fertilizer (eutrophication)
pesticides (kill non target)
oil and gas (suffocate fish/kill)