AP Environmental Exam

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)
ionizing radiation
radiation with enough energy to free electrons from atoms forming ions, may cause cancer (ex. gamma, X-rays, UV)
High Quality Energy
organized and concentrated, can perform useful work (ex. fossil fuels and nuclear)
Low Quality Energy
disorganized, dispersed (ex. heat in ocean or air/wind, solar)
Natural radioactive decay
unstable radioisotopes decay releasing gamma rays, alpha and beta particles (ex. Radon)
Half-life
the time it takes for 1/2 of the mass of a radioisotope to decay. A radioactive isotope must be stored for approximately 10 half-lives until it decays to a safe level
Nuclear Fission
nuclei of isotopes split apart when struck by neutrons
Nuclear Fusion
2 isotopes of light elements (H) forced together at high temperatures until they fuse to form a heavier nucleus. Happens in the sun; very difficult to accomplish on Earth
Ore
a rock that contains a large enough concentration of a mineral making it profitable to mine
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
Soil Conservation Methods
conservation tillage, crop rotation, contour plowing, organic fertilizers
Soil Salinization
in arid regions, water evaporates leaving salts behind (ex. Fertile crescent, southwestern US)
Water Logging
water completely saturates soil, starves plant roots of oxygen, rots roots
Hydrologic Cycle Components
evaporation, transpiration, runoff, condensation, precipitation, infiltration
Watershed
all of the land that drains into a body of water
Aquifer
underground layers of porous rock allow water to move slowly
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)
trade winds weaken and warm surface water moves toward South America. diminished fisheries off South America, drought in western Pacific, increased precipitation in southwestern North America, fewer Atlantic hurricanes
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
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 and 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
Photosynthesis
plants convert CO2 (atmospheric carbon) into complex carbohydrates (glucose)
Aerobic Respiration
oxygen consuming producers, consumers and decomposers break down complex organic compounds and convert C back into CO2
Biotic
the living components of an ecosystem
Abiotic
the nonliving components of an ecosystem
Producer/Autotroph
organisms that make their own food–photosynthetic life (plants)
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 of thermodynamics), not all biomass is digested and absorbed, predators expend energy to catch prey
Primary Succession
development of communities in a lifeless area not recently inhabited by life (ex. lava flow, retreating glacier)
Secondary Succession
life progresses where soil remains (ex. clear-cut/burned forest, old farm, vacant lot)
Mutualism
symbiotic relationship where both organisms benefit
Commensalism
symbiotic relationship where both organisms benefit
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, famines, and pestilence (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 humber of children a couple must have to replace themselves (averages 2.1 in more developed nations, 2.7 in less developed nations)
World Population
a little over 6 billion
Demographic Transition Model
Preindustrial stage, transitional stage, industrial stage, postindustrial stage
Preindustrial stage
birth and death rates high, population grows slowly, infant mortality high
Transitional stage
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 and 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)USA 4)Indonesia
Low Status of Women
Most important factor keeping population growth rates high
Methods to Decrease Birth Rates
family planning, contraception, economic rewards and penalties
Composition of Water on Earth
97.5% seawater, 2.5% freshwater
Aquaculture
farming aquatic species, commonly salmon, shrimp, tilapia, oysters
Point Source
source from specific location such as pipe or smokestack
Non-Point Source (Area/Dispersed Source)
source spread over an area such as agricultural/feedlot runoff, urban runoff, traffic
Primary Sewage Treatment
first step of sewage treatment; eliminates most particulate material from raw sewage using grates, screens, and gravity (settling)
Secondary Sewage Treatment
second step of sewage treatment; bacteria breakdown organic waste, aeration accelerates the process
BOD (Biological Oxygen Demand)
amount of dissolved oxygen needed by aerobic decomposers to break down organic material
Eutrophication
rapid algal growth (algal bloom) caused by an excess of nitrogen and phosphorus, blocks sunlight, causing the death/decomposition of aquatic of plants, decreasing dissolved oxygen (DO), suffocating fish
Hypoxia
water with very low dissolved oxygen levels, the end result of eutrophication for example
CAFE standards (Corporate Average Fuel Economy standards)
enacted into law in 1975, established fuel efficiency standards for passenger cars and light trucks. fuel economy ratings must average at least 27.5 mpg for entire line of manufacturer’s passenger cars
Primary air pollutants
produced by humans and nature (CO, CO2, SO2, NO, hydrocarbons, particulates)
Secondary Air Pollutants
formed by reaction of primary pollutants
Particulate Matter
sources include burning fossil fuels and car exhaust. Effects include reduced visibility, respiratory irritation. Methods of reductions include filtering, electrostatic precipitators, alternative energy.
Nitrogen Oxides (NOx)
Major source is auto exhaust. Primary and secondary effects include acidification of lakes. respiratory irritations, 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
Carbon Dioxide
sources include combustion of fossil fuels. Effects: greenhouse gas-contributes to global warming. Reduction accomplished by increased fuel efficiency (gas mileage), mass transit (reduction)
Carbon Monoxide
Sources include incomplete combustion of fossil fuels. Effects:binds to hemoglobin reducing bloods ability to carry O2. Reduction accomplished by catalytic converters, oxygenated fuel, mass transit
Photochemical Smog
formed by chemical reactions involving sunlight (NO, VOC, O2)
Acid Deposition
caused by sulfuric and nitric acids resulting in lowered pH of surface waters
Greenhouse Gases
Most significant: H2O, CO2, methane (CH4), CFCs. Trap outgoing infrared energy (heat) causing earth to warm.
Greenhouse Effect
vital process, requred for life to exist but if accelerated 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. Negative effects: increased UV, skin cancer, cataracts, decreased plant growth
Municipal Solid Waster
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; volume of garbage which may be compacted 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
Best Solution for Waste Problem
reduce the amount of waste at the source
Brownfield
abandoned industrial sites
Keystone Species
species whose role in an ecosystem is more important than others
Indicator Species
species that serve as early warning that an ecosystem is being damaged
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, increases profits for farmers. Cons:genetic resistance, ecosystem imbalance, pesticide treadmill, persistence, bioaccumulation, and biological magnification
Natural Pest Control
better agricultural practices, genetically resistant plants, natural enemies, biopesticides
Genetically Modified Organisms (GMOs)
new organisms created by altering the genetic material (DNA) of existing organisms; usually in an attempt to remove undesirable or create desirable characteristics in the new organism
Electricity Generation
steam, from water boiled by fossil fuels or nuclear energy, or falling water is used to turn a generator
Petroleum (Crude Oil) Formation
microscopic aquatic organisms in sediments converted by heat and pressure into a mixture of hydrocarbons
Petroleum
Pros: cheap, easily transported, high-quality energy. Cons: reserves depleted soon, pollution during drilling, transport and refining, land subsidence, burning oil produces CO2
Coal Formation
prehistoric plants buried un-decomposed in oxygen-depleted water of swamps/bogs converted by heat and pressure
Ranks of Coal
peat, lignite, bituminous, anthracite
Nuclear Reactor
consists of core, control rods, moderator, steam generator, turbine, containment building
Alternate Energy Sources
wind, solar, waves, biomass, geothermal, fuel cells
Remediation
return a contaminated area to its original state
LD-50
amount of a chemical that kills 50% of the animals in a test population
Troposphere
first layer of atmosphere 0-10 miles above Earth’s surface. contains weather, greenhouse gases (bad ozone)
Stratosphere
second layer of atmosphere 10-30 miles about Earth’s surface. contains protective ozone layer
Inversion Layer (Temperature Inversion)
warm layer of air above a cooler layer traps pollutants close to Earth’s surface
Mutagen
substances that cause changes in DNA; may result in hereditary changes
Teratogen
substances that cause fetus deformities (birth defects)
Carcinogen
substances that cause cancer
Dioxin
one of the most toxic human-made chemicials; stable, long-lived, by-product of herbicide production enters environment as fallout from the incineration of municipal and medical waste and persists for many years
PCBs (Polychlorinated Biphenyls)
stable, long-lived, carcinogenic chlorinated hydrocarbons. produced by electronics industry
Multiple Use Public Lands
National Forest and National Resource lands
Moderately Restricted use Public Lands
National Wildlife Refuges
Restricted use Public Lands
National Parks and National Wilderness Preservation System
Divergent Plate Boundaries
tectonic plate spreading apart, new crust bein formed (ex. mid-ocean ridges, rift valleys)
Convergent Plate Boundaries
tectonic plates with the oldest crustal material on Earth moving together, one moving under another (ex. mid-ocean trenches). mineral deposits and volcanoes are most abundant here
Transform Fault
tectonic plates sliding past one another (ex. San Andreas Fault)