ESR 172 Final

Proton-middle(positive charge)

Electron-Outer(negative charge)

Neutron- Middle(neutral)

Number of protons

Protons plus neutrons

Energy of atomic nucleus

Same protons-- Different # of neutrons-- Different atomic mass #'s

form of an element that spontaneously undergoes radioactive decay

Radioisotope emits radiation and changes to another isotope

Time required for one-half of a given amount of an isotope to decay

Emitted from atomic nucleus as result of radioactive decay and nuclear reactions

Two protons and two neutrons

Electrons

Electromagnetic radiation

Radiation absorbed dose

• Atomic bomb detonations
• Uranium mine workers
• Etc.

• Vomiting
• Abortion of pregnancies
• Cancers (lung, thyroid, etc.)
• Radiation burns

Deposit of radioactive materials around the world

Intense radiation kills organisms directly

Radioisotopes enter food chains

Nuclear fuel becomes so hot that it breaches the reactor and contaminates the outside environment with radioactivity (Chernobyl)

• Oceans- 97.2%
• Ice caps- 2.15%

• Water removed from its source for use and returned to its source after use
• Example: water used to cool industrial processes goes to cooling ponds and then discharged to source

• Use of rivers for
• Navigation
• Hydroelectric power generation
• Fish and wildlife habitats
• Recreation

• Thermoelectric
• Irrigation

Areas inundated by water or where the land is saturated to a depth of a few centimeters for at least a few days per year

• Contaminants and sediments are filtered
• Saturated soil stores water
• Bacteria breakdown contaminents

water below the water table

Upper surface of groundwater

Groundwater which can be obtained at a useful rate

Groundwater withdrawal from wells is greater than natural inflow

Amount of oxygen consumed by microorganisms as they break down organic matter

When BOD high, dissolved oxygen content of water may become too low

• Difficult to monitor disease-carrying organisms directly
• Presence of fecal coliform bacteria indicates fecal material present
• Organisms that cause waterborne diseases may be present

• Drinking water
• No fecal coliform bacteria

• Swimming water
• Not more than 200 cells per 100 ml of water

• Human processes (fertilizers, sewage-treatment plants, etc.) add nutrients to a body of water
• Effects--
• Increase in growth of aquatic plants (algae)
• Water below surface shaded
• BOD increases when algae die
• Oxygen content of water reduced
• Fish and other organisms die

• Nearshore environments
• Nitrogen causes cultural eutrophication
• Low dissolved oxygen concentrations
• Fish and shrimp swim away
• Shellfish, crabs, etc. killed

• Rock and mineral fragments (gravel, sand, silt, clay)
• Results from erosion

• Chokes streams
• Fills lakes, reservoirs, etc.
• Buries vegetation
• Smothers coral reefs

Lower part of the atmosphere (6-8 mi)

• Weather
• Atmospheric conditions for a region of Earth over short periods of time

• Climate
• Atmospheric conditions for a region on Earth over long periods of time

A natural or human-induced increase in the average global temperature of the atmosphere

Processes that result from human activities

• Combustion of fossil fuels
• Deforestation

• Relative contribution
• 50%-60%

• Landfills
• Production of coal and natural gas
• Cultivation of rice
• Raising of cattle

• Relative contribution
• 12%-20%

• Aerosol propellants in spray cans
• Refrigeration units

• Relative contribution
• 15%-25%

• Agriculture (application of fertilizers)
• Burning of fossil fuels

• Relative contribution
• 5%

Strong correlation

Global warming causes greater temperature increases at polar regions because of a positive-feedback mechanism

• Primary cause
• Thermal expansion of warming ocean water

• Secondary cause
• Melting of glacial ice

• Increased coastal erosion
• Coastal wetland loss due to landward migration of estuaries and salt marshes
• Loss of property, whole islands

Organisms have a range of tolerance and an optimum level for each environmental factor that affects them

• Six most common
• Responsible for most air pollution problems

• Major sources
• Burning fossil fuels (coal in power plants)

• Effects
• Damage to lungs
• Precursor to acid rain

• Major sources
• Automobiles
• Burning fossil fuels (natural gas and coal)

• Effects
• Development of smog
• Precursor to acid rain

• Major sources
• Incomplete burning of fuels (automobiles)

• Effects
• Reduces oxygen transport
• Headache, fatigue, nausea
• Reduces endurance

• A photochemical oxidant in smog
• Major sources
• Automobiles
• Burning fossil fuels

• Effects
• Lung and airway damage
• Kills leaf tissue, whole plants

• Major sources
• Dust from farming
• Burning fossil fuels

• Effects
• Lung cancer
• Bronchitis

Gradual reduction in solar radiation that reaches the Earth due to particulate pollution

• pH of pure rainfall = 5.6
• Acid rain is precipitation in which the pH is below 5.6

• Sulfur dioxide (SO2 ) and nitrogen oxides (NOx ) major contributors
• Transformed to sulfuric acid (H2 SO4 ) and nitric acid (HNO3 ) in the atmosphere

• Forest ecosystems
• Kills and weakens trees
• Loss of nutrients from soil
• Kills fish, aquatic species
• Loss of nutrients from water
• Damages building materials
• Damages lungs when inhaled

Warmer air found above cooler air

L.A.-type smog, or brown air

Nitrogen oxides (NOx)

Organic compounds (hydrocarbons)

Solar radiation (sunlight)

• Describes air pollution on a given day
• AQI greater than 100 is unhealthy