safsfasf

Get a hint

hint

Tragedy of the Commons (TOC)

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

1. fill hole

2. restore contours of land

3. return topsoil, remove bad stuff

4. 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)