Second Law of Thermodynamics
when energy is changed from one form to another, some useful energy is always degraded into lower quality energy (usually heat).
Ionizing radiation
radiation w/enough energy to free electrons from atoms forming ions, may cause cancer (ex. gamma, X-rays, UV).
High Quality Energy
organized & concentrated, can perform useful work (ex. fossil fuels & nuclear).
Low Quality Energy
disorganized, dispersed (ex. heat in ocean or air/wind, solar).
Natural radioactive decay
unstable radioisotopes decay releasing gamma rays, alpha & beta particles (ex. Radon).
Half-life
the time it takes for 1?2 of the mass of a radioisotope to decay.
Estimate of how long a radioactive isotope must be stored until it decays to a safe level
approximately 10 half-lives.
Nuclear Fission
nuclei of isotopes split apart when struck by neutrons. (Current nuclear energy)
Nuclear Fusion
2 isotopes of light elements (H) forced together at high temperatures till they fuse to form a heavier nucleus. Happens in the Sun, very difficult to accomplish on Earth, prohibitively expensive.
Ore
a rock that contains a large enough concentration of a mineral making it profitable to mine.
Organic fertilizer
slow acting and long lasting because the organic remains need time to be decomposed.
Best solution to energy shortage
conservation and increased efficiency
Mineral Reserve
identified deposits currently profitable to extract.
Surface mining
cheaper, can remove more minerals, less hazardous to workers.
Humus
organic, dark material remaining after decomposition by microorganisms.
Leaching
removal of dissolved materials from soil by water moving downwards through soil.
Loam
perfect agricultural soil with equal portions of sand, silt, and clay.
Conservation
allows the use of resources in a responsible manner
Preservation
setting aside areas and protecting them from human activities
Restoration
to bring back to former condition, active restoration seeks to reestablish a diverse, dynamic community at a site that has been degraded
Remediation
Most often used with cleanup of chemical contaminants in a polluted area
Mitigation
Repairing/rehabilitating a damaged ecosystem or compensation for damage, most often by providing a substitute replacement area; frequently involves wetland ecosystems.
Reclamation
typically used to describe chemical or physical manipulations carried out in severely degraded sites, such as open-pit mines or large-scale construction
Soil Conservation Methods
conservation tillage, crop rotation, contour plowing, organic fertilizers. (know WHY)
Hydrologic Cycle Components
evaporation, transpiration, runoff, condensation, precipitation, and infiltration.
Aquifer
any water-bearing layer in the ground.
Cone of Depression
lowering of the water table around a pumping well.
Salt Water Intrusion
near the coast, overpumping of groundwater causes saltwater to move into the aquifer.
ENSO
El Nino Southern Oscillation, see-sawing of air pressure and trade winds over the South Pacific
During an El Nino year
Trade winds weaken & warm water sloshes towards SA
During a La Nina "normal" year
Easterly trade winds and ocean currents pool warm water in the western Pacific, allowing upwelling of nutrient rich water off the West coast of South America.
Effects of El Nino
upwelling decreases disrupting food chains and diminished fisheries off South America, drought in western Pacific, increased precipitation in southwestern North America, fewer Atlantic hurricanes.
Nitrogen Fixation
because atmospheric N cannot be used directly by plants, it must first be converted into ammonia by bacteria.
Ammonification
decomposers covert organic waste into ammonia.
Nitrification
ammonia is converted to nitrate ions (NO3-).
Assimilation
inorganic N is converted into organic molecules such as DNA/amino acids & proteins.
Denitrification
bacteria convert ammonia back into N.
Phosphorus
does not exist as a gas; released by weathering of phosphate rocks, it is a major limiting factor for plant growth. Phosphorus cycle is slow, and not atmospheric.
Phosphorus does not circulate as easily as N because
it does not exist as a gas, but is released by the weathering of phosphate rocks.
Excess phosphorus is added to aquatic ecosystems by
runoff of animal wastes, fertilizer, discharge of sewage.
Sustainability
the ability to meet humanities current needs without compromising the ability of future generations to meet their needs
Photosynthesis
plants convert CO2 (atmospheric C) into complex carbohydrates (glucose C6H12O6).
Aerobic Respiration
oxygen consuming producers, consumers & decomposers break down complex organic compounds & convert C back into CO2.
Largest reservoirs of Carbon (carbon sinks)
(1) carbonate rocks (2) oceans
Net Primary Productivity
amount of carbon from the atmosphere that gets added to green plants per unit time, rate at which new vegetation is added, calculated by total gain of plant biomass minus the losses due to plant respiration, this net gain is available to all other organis
Biotic/Abiotic
living/nonliving components of an ecosystem.
Producer/Autotroph
organisms that make their own food�photosynthetic life. (Plants and some algae and bacteria)
Fecal coliform bacteria
indicator of sewage contamination in the water
Trophic Levels
producers primary consumer secondary consumer tertiary consumer.
Energy Flow through Food Webs
10% of the usable energy is transferred to the next trophic level. Reason: usable energy lost as heat (2nd law), not all biomass is digested & absorbed, predators expend energy to catch prey.
First Law of Thermodynamics
energy is neither created nor destroyed, but may be converted from one form to another.
Chlorine
good for disinfection of water
Cogeneration
using waste heat to make electricity
Primary succession
development of communities in a lifeless area not previously inhabited by life (ex. lava).
Secondary succession
life progresses where soil remains (ex. clear-cut forest, old farm).
Mutualism
symbiotic relationship where both organisms benefit.
Commensalism
symbiotic relationship where one organism benefits & the other is unaffected.
Parasitism
relationship in which one organism (the parasite) obtains nutrients at the expense of the host.
Carrying Capacity
the number of individuals that can be sustained in an area.
r-strategist
reproductive strategy in which organisms reproduce early, bear many small, unprotected offspring (ex. insects, mice).
K-strategist
reproductive strategy in which organisms reproduce late, bear few, cared for offspring (ex. humans, elephants).
Natural Selection
organisms that possess favorable adaptations pass them onto the next generation.
Thomas Malthus
human population cannot continue to increase. Consequences will be war, famine & disease.
Doubling Time
(rule of 70) doubling time equals 70 divided by percent growth rate. (ex. a population growing at 5% annually doubles in 70 � 5 = 14 years)
Replacement Level Fertility
the number of children a couple must have to replace themselves (2.1 more developed, 2.7 less).
World Population
7 billion
US Population
300 million
Demographic Transition Model
the stages a country must pass through when transitioning from developing to developed countries, triggered by economic development.
Preindustrial stage
birth & death rates high, population grows slowly, infant mortality high.
Transitional stage
triggered by death rate (infant mortality) lower, birth rates remain high, better health care, population grows fast.
Industrial stage
decline in birth rate, population growth slows.
Postindustrial stage
low birth & death rates.
Age Structure Diagrams
broad base =rapid growth; narrow base negative growth; uniform shape zero growth
Most Populous Nations
(1) China (2) India (3) U.S.
Most important thing affecting population growth
low status of women
Methods to Decrease Birth Rates
family planning, contraception, economic rewards & penalties - know examples, why, and how.
Composition of Water on Earth
97.5% seawater, 2.5% freshwater.
Soil Salinization
in arid regions, water evaporates leaving salts behind. (ex. Fertile crescent, southwestern US)
Ways to conserve water
agriculture - drip irrigation, industry - recycling, conservation, home - conservation, use gray water, repair leaks, use low flow fixtures
Biome
large distinct terrestrial region having similar climate, soil, plants and animals
Positive feedback
when a change in some condition triggers a response that intensifies the changing condition (ex: warmer earth, snow melts, less sunlight reflected off the ice, makes earth even warmer)
Negative feedback
when a change in some condition triggers a response that counteracts the changed condition (ex: warmer earth, more ocean evaporation, more clouds, less sunlight reaches the ground - cooler earth)
Point Source
from specific location such as pipe or smokestack
Non-Point Source
from over an area such as agricultural (farm) runoff, traffic.
BOD
Biological Oxygen Demand, amount of dissolved oxygen needed by aerobic decomposers to break down organic materials.
Eutrophication
rapid algal growth caused by an excess of nitrogen & phosphorus.
Hypoxia
when aquatic plants die, the BOD rises as aerobic decomposers break down the plants, the DO drops & the water cannot support life
Primary Air Pollutants
produced by humans & nature (CO, CO2, SO2, NO, hydrocarbons, particulates).
Secondary Air Pollutants
formed by reaction of primary pollutants. (ozone, smog, acid rain)
Particulate Matter (sources, effects, reduction)
sources include burning fossil fuels and car exhaust. Effects include reduced visibility, respiratory irritation. Methods of reduction include filtering, electrostatic precipitators, alternative energy).
Nitrogen Oxides
(NOx) Major source is auto exhaust. Primary and secondary effects include acidification of lakes, respiratory irritation, leads to smog and ozone. Reduced using catalytic converters.
Equation for acid formation
NO + O2 NO2 + H2O HNO3.
Ozone
Secondary pollutant, NO2 + UV NO + O; O + O2 O3, with VOCs. Causes respiratory irritation and plant damage. Reduced by reducing NO emissions and VOCs.
Sulfur Oxides
(SOx) Primary source is coal burning. Primary and secondary effects include acid deposition, respiratory irritation, plant damage. Reduction methods include: scrubbers, burn low sulfur fuel.
Equation for acid formation
SO2 + O2 SO3 + H2O =H2SO4
Carbon Oxides
(CO2 and CO) Sources include burning fossil fuels, incomplete combustion. Effects: CO binds to hemoglobin reducing bloods ability to carry O; CO2 contributes to global warming. Reduction accomplished by catalytic converters, emissions testing, oxygenated
Industrial Smog
found in cities that burn large amounts of coal
Photochemical Smog
formed by chemical reactions involving sunlight (NO, VOC, O)
Acid Deposition
caused by sulfuric and nitric acids resulting in lowered pH of surface waters
Greenhouse Gases
Most significant: H2O, CO2, O3, methane (CH4), CFCs. Trap outgoing infrared energy (heat) causing earth to warm.
Greenhouse Effect
a vital process, required for life to exist on Earth. If accelerated, bad, leads to global warming.
Effects of Global Warming
rising sea level (due to thermal expansion not melting ice), extreme weather, droughts ((famine), and extinctions.
Ozone Depletion
caused by CFCs, methyl chloroform, carbon tetrachloride, halon, methyl bromide all of which attack stratospheric ozone.
Effects of Ozone Depletion
increased UV, skin cancer, cataracts, and decreased plant growth.
Radon
radioactive gas, formed from the decay of Uranium in the earth's crust, gets into houses through cracks in foundation, causes lung cancer
Municipal Solid Waste
is mostly paper and mostly put into landfills.
Sanitary Landfill
problems include leachate, which is solved using a liner with a collection system; methane gas, which may be collected and burned and the volume of garbage, which may be compacted and/or reduced.
Incineration
Advantages-volume of waste reduced by 90% and waste heat can be used. Disadvantages-toxic emissions (polyvinyl chloride, dioxin), scrubbers and electrostatic precipitators needed, ash disposal (contains heavy metals).
Best Solution for Waste Problem
reduce the amount of waste at the source.
Keystone Species
species whose role in an ecosystem is more important than others. Ex. Sea Otter
Indicator Species
species that serve as early warnings that an ecosystem is being damaged. Ex. Trout, Reptiles, Birds
Most Endangered Species
have a small range, require large territory or live on an island.
In Natural Ecosystems
50-90% of pest species are kept under control by: predators, diseases, parasites.
Major Insecticide Groups
chlorinated hydrocarbons�ex. DDT; organophosphates�ex. malathion; carbamates�ex. aldicarb
Pesticide Pros
saves lives from insect transmitted disease, increases food supply, and increases profits for farmers.
Pesticide Cons
genetic resistance, ecosystem imbalance, pesticide treadmill, persistence, bioaccumulation, and biological magnification.
Natural Pest Control
better agricultural practices, genetically resistant plants, natural enemies, and biopesticides, sex attractants.
Electricity Generation
steam, from water boiled by fossils fuels or nuclear energy, or falling water is used to turn a generator.
Petroleum Formation
microscopic aquatic organisms in sediments converted by heat & pressure into a mixture of hydrocarbons.
Petroleum Pros
cheap, easily transported, high-quality energy.
Petroleum Cons
reserves depleted soon, pollution during drilling, transport and refining, burning makes CO2.
Coal Formation
peat, lignite, bituminous coal, anthracite coal.
Nuclear Reactor
consists of a core, control rods, moderator, steam generator, turbine, containment building.
Alternative Energy Sources
wind, solar, waves, biomass, geothermal, fuel cells
True cost/external costs
harmful environmental side effects that are not reflected in the product's price
LD-50
the amount of a chemical that kills 50% of the animals in a test population
Mutagen
causes hereditary changes.
Teratogen
causes fetus deformities.
Carcinogen
causes cancer.
Multiple Use Public Lands
National Forest & National Resource lands
Moderately Restricted Use Public Lands
National Wildlife Refuges
Restricted Use Public Lands
National Parks, National Wilderness Preservation System
Volcanoes and Earthquakes
Occur at tectonic plate boundaries: divergent�spreading (ex. mid-ocean ridges); convergent (ex.trenches); transform fault,�sliding (ex. San Andreas).
Mineral Deposits
most abundant at convergent plate boundaries.
Garret Hardin & Tragedy of the Commons
Global commons such as atmosphere and oceans are used by all and owned by none leading to rapid depletion.
Ionizing radiation
enough energy to knock electrons from atoms forming ions, capable of causing cancer
High Quality Energy
organized & concentrated, can perform useful work (fossil fuel & nuclear)
Low Quality Energy
disorganized, dispersed (heat in ocean or air wind, solar)
First Law of Thermodynamics
Energy is neither created nor destroyed, but may be converted from one form to another
Second Law of Thermodynamics
When energy is changed from one form to another, some useful energy is always degraded into lower quality energy (usually heat)
Natural radioactive decay
unstable radioisotopes decay releasing gamma rays, alpha & beta particles
Half life
the time it takes for half the mass of a radioisotope to decay
Estimate of how long a radioactive isotope must be stored until it decays to a safe level
approximately 10 half lives
Nuclear Fission
Nuclei of isotopes split apart when struck my neutrons
Nuclear Fusion
2 isotopes of light elements (H) forced together at high temperatures until they fuse to form a heavier nucleus. Expensive, break even point not reached yet
Ore
a rock that contains a large enough concentration of a mineral making it profitable to mine
Organic Fertilizer
slow acting and long lasting because the organic remains need time to be decomposed
Best solution to energy shortage
conservation and increase efficiency
Surface mining
cheaper and can remove more mineral, less hazardous to workers. Really bad for the environment
Humus
organic, dark material remaining after decomposition by microorganisms
leaching
removal of dissolved materials from soil by water moving downwards
Illuviation
deposit of leached material in lower soil laters
Loam
perfect agricultural soil with equal portions of sand, silt, clay
Conservation
allows the use of resources in a responsible manner
Preservation
setting aside areas and protecting them from human activities
Parts of the hydrolic cycle
evaporation, transpiration, runoff, condensation, precipitation, infiltration
Aquifer
any water bearing later in the ground
Cone of depression
lowering of the water table around a pumping well
Salt water intrusion
near the coast, overpumping of groundwater causes saltwater to move into the aquifers
ENSO
El Nino Souther Oscillation, see-sawing of air pressure over the S. Pacific
During an El Nino year
trade winds weaken and warm water sloshed back to South Africa
During a non-El Nino year
Easterly trade winds and ocean currents pool warm water in the western Pacific, allowing upwelling of nutrient rich water off the west coast of South Africa
Effects of El Nino
upwelling decreases disrupting food chains, North Us has mild winters, South West Us has increased rainfall, less Atlantic Hurricanes
Nitrogen Fixing
because atmosphere Nitrogen cannot be used directly by plants it must first be converted into ammonia by bacteria
Ammonification
decomposers convert organic waste into ammonia
Nitrification
ammonia is converted to nitrate ions (NO3)
Assimilation
inorganic nitrogen is converted into organic molecules such as DNA/amino acids and proteins
Denitrification
bacteria convert ammonia back into nitrogen
Phosphorus does not circulate as easily as Nitrogen because:
it does not exist as a gas, but is released by weathering of phosphate rocks
Sustainability
the ability to meet humanity's current needs without compromising the ability of future generations to meet their needs
Excess phosphorus is added to aquatic ecosystems by:
runoff of animal wastes, fertilizer, discharge of sewage
Photosynthesis
plants convert atmospheric Carbon dioxide into complex carbohydrates (glucose)
Aerobic respiration
oxygen consuming producers consumers and decomposers break down complex organic compounds and convert carbon back into carbon dioxide
largest reservoirs of Carbon
carbonate rocks first, oceans second
biotic/abiotic
living and nonliving components of an ecosystem
producer/autotroph
photosynthetic life
fecal coliform/enterococcus
indicator of sewage contamination
energy flow in food webs
only 10% of the usable energy is transformed because usable enrgy lost as heat (2nd law), not all biomass is digested and absorbed, predators expend energy to catch prey
Chlorine
Good-disinfection of water, bad-forms trihalomethanes
primary succession
development of communities in a lifeless area not preciously inhabited by life (lava)
secondary succession
life progresses where soil remains (clear cut forest, fire)
cogeneration
using waste heat to make electricity
mutualism
symbiotic relationship where both partners benefit
commensalism
symbiotic relationship where one partner benefits and the other is unaffected
parasitism
relationship in which one partner obtains nutrients at the expense of the host
biome
large distinct terrestrial region having similar climate, soil, plants and animals
carrying capacity
the number of individuals that can be sustained in an area
r strategist
reproduce early, many small unprotected offspring
K strategist
reproduce late, few, cared for offspring
Positive feedback
when a change in some condition triggers a response that intensifies the changing condition (ex: warmer earth-snow melts-less sunlight is reflected and more is absorbed, therefore warmer earth)
Natural selection
organisms that possess favorable adaptations pass them onto the next generation
Malthus
said human population cannot continue to increase, consequences will be war, famine and disease
doubling time
rule of 70, 70 divided by the % growth
Replacement level fertility
the number of children a couple must have to replace themselves (2.1 developed, 2.7 developing)
Preindustrial stage
birth and death rates HIGH, population grows SLOWLY, infant mortality HIGH
Transitional stage
death rate LOWER, better HEALTH CARE, population grows FAST (where we are now)
Industrial stage
decline in birth rate, population growth SLOWS
Postindustrial stage
low birth and death rates (population evens out)
Age structure diagrams
(broad base, rapid growth) (narrow base, negative growth) (uniform shape, 0 growth)
Most important thing affecting population growth
low status of women
ways to decrease birth rate
family planning, contraception, economic rewards & penalties
Percent of water type on the earth
97.5% seawater (salt water), 2.5% freshwater
Salinization of soil
in arid regions, water evaporates leaving salts behind
ways to conserve water
(agriculture, drip/trickle irrigation, center pivot) (industry, recycling) (home, use gray water, repair leaks, low flow fixtures, dual flush)
point vs. nonpoint sources
(point, from specific location such as pipe) (non-point, from over an area such as runoff)
BOD
Biological oxygen demand, amount of dissolved oxygen needed by aerobic decomposers to break down organic materials)
Eutrophication
rapid algal growth caused by an excess of nitrogen and phosphates (bad to an extent, low oxygen levels)
Hypoxia
when aquatic plants die, the BOD rises as aerobic decomposers break down the plants, the dissolved oxygen drops and the water cannot support life
Minamata Disease
mental impairments caused by mercury
Primary air pollutants
produced by humans and nature (CO, CO2, SO2, NO,hydrocarbons, particulates)
Negative feedback loop
when a changing in some condition triggers a response that counteracts the changed condition (ex. warmer earth-more ocean evaporation-more stratus clouds-less sunlight reaches the ground-therefore cooler earth)
Particulate matter (source, effect, reduction)
(burning fossil fuels and diesel exhaust) (reduces visibility and respiratory irritation) (filtering, precipitators, alternative energy)
nitrogen oxides (source, effect, reduction)
(auto exhaust) (acidification of lakes, respiratory irritation, leas to smog & ozone) (catalytic converter)
Sulfur oxides (source, effects, reduction)
(coal burning) (acid deposition, respiratory irritation, damages plants) (scrubbers, burn low sulfur fuel)
carbon oxides (source, effects, reduction)
(auto exhaust, incomplete combustion) (CO binds to hemoglobin reducing bloods ability to carry O2, CO2 contributes to global warming) (catalytic converter, emission testing, oxygenated fuel, mass transit)
ozone (formation, effects, reduction)
(secondary pollutant, with VOC's) (respiratory irritant, plant damage) (reduce NO emissions and VOC's)
Radon
radioactive gas, formed from the decay of Uranium, causes lung cancer
Photochemical smog
formed by chemical reactions involving sunlight (NO, VOC, O)
Acid deposition
caused by sulfuric and nitric acids resulting in lowered pH of surface waters
Greenhouse gases
Water Vapor,Carbon Dioxide, Ozone, Methane, Nitrous Oxide, CFC's (effects: they trap outgoing infrared (heat) energy causing earth to warm)
Effects of global warming
rising seal level, extreme weather, droughts, extinctions
Ozone depletion caused by
CFC's, methyl chloroform, carbon tetrachloride, halon, methyl bromide all of which attack stratospheric ozone
Effects of ozone depletion
increased UV, skin cancer, cataracts, decreased plant growth
Municipal solid waste is mostly
paper and most is landfilled
true cost/external costs
harmful environmental side effects that are not reflected in a product's price
sanitary landfill problems and solutions
(problems: leachate, methane gas, volume of garbage) (linear with collection system, collect gs and burn, compact and reduce)
Incineration advantages
volume of waste reduced by 90% and waste heat can be used
Incineration disadvantages
toxic emissions, scrubbers and electrostatic precipitators needed, ash disposal (contains heavy metals)
Best way to solve waste problem
reduce the amounts of waste at the source
Keystone species
species whose role in an ecosystem are more important than others. (ex:sea otter, dung beetle). The species effects the life of other species, if they were gone, it would completely effect the whole ecosystem
Indicator species
species that serve as early warnings that an ecosystem is being damaged ex. trout
Most endangered species
have a small range, require large territory or live on an island
In natural ecosystems 50-90% of pest species are kept under control by:
predators, diseases, parasites
pesticide pros
saves lives from insect transmitted disease, increases food supply, increases profits for farmers
pesticide cons
genetic resistance, ecosystem imbalance, pesticide treadmill, persistence, bioaccumulation, biological magnification
natural pest control
better agricultural practices, genetically resistant plants, natural enemies, biopesticides, sex attractants
electricity is generated by
the use of steam (from water boiled by fossil fuels or nuclear) or the fall of water to turn a generator
petroleum forms from
microscopic aquatic organisms in sediments converted by heat and pressure into a mixture of hydrocarbons
petroleum pros
cheap, easily transported, high quality energy
petroleum cons
genetic resistance, ecosystem imbalance, pesticide treadmill, persistence, bioaccumulation, biological magnification
two most serious NUCLEAR accidents
(Chernobyl, Ukraine) (Three Mile Island, Pennsylvania)
Alternative energy sources
wind, solar,waves, biomass, geothermal, fuel cells
LD50
the amount of a chemical that kills 50% of the animals in a test population
Mutagen, Teratogen, Carcinogen
causes hereditary changes, fetus deformities, cancer
Garret Hardin and The Tragedy of the Commons
Freedom to breed is bringing ruin to all. Global commons such as atmosphere and oceans are used by all and owned by none
Volcanoes and Earthquakes occur
at plate boundries
Sources of mercury
burning coal, compact fluorescent bulbs
Major source of sulfur
burning coal
threshold dose
the maximum dose that has not measurable effect
surface mining control and reclamation act
requires coal strip mines to reclaim the land
Madrid protocol
moratorium on mineral exploration for 50 years in Antarctica
Safe drinking water act
set maximum containment levels for pollutants in drinking water that may have adverse effects on human health
clean water act
set maximum permissible amounts of water pollutants in drinking water that may have adverse effects on human health
Kyoto Protocol
controlling global warming by setting greenhouse gas emissions targets for developed countries
Montreal Protocol
phase-out of ozone depleting substances
Resource conservation and recovery act
controls hazardous waste with a cradle to grave system