Definitions Flashcards
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 w/ 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 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 mass of a radioisotope to decay. A radioactive isotope must be stored for approximately 10 half-lives until it decays to a safe lever
Nuclear fission
Nuclei of isotopes split apart when stuck by neutrons
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
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 soul w/ 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, and 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, over pumping of groundwater causes saltwater to move into the aquifer
ENSO
El Niño Oscillation, trade winds weaken and warm surface water moves toward Souther America. Diminished fisheries off South America, drought in western Pacific, increase precipitation in Southwestern North America, fewer Atlantic hurricanes
La Niña
“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 covered into ammonia by bacteria
Ammonification
Decomposers convert organic waste into ammonia
Nitrification
Ammonia is covered in 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
Photosynthesis
Plants convert CO2 (atmospheric carbon) into complex carbohydrates (C6H12O6)
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/ Autograph
Organisms that 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 Thermodynamics), not all biomass is digested and absorbed, predators expend energy to catch prey.
Primary succession
Development of communities in a lifeless area nor recently inhabited by life (ex lava flow, retreating glacier)
Secondary succession
Life progresses where soil remains (ex clear cut/burned forrest, old farm, vacant lot)
Mutualism
Symbiotic relationship where both organisms benefit
Commensalism
Symbiotic relationship where one benefits and 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 produce late, bear few, cared for offspring (ex humans, elephants)
Natural selection
Organisms that process favorable adaptations pass them onto the next generation
Thomas Malthus
“Human population cannot continue to increase. Consequences will be war, famine, and pestilence (disease)”
Doubling Time
(Rule of 70) doubling time equals 70 divided by percent growth rate (ex a pop of 5%annually doubles in 70/5=14years)
Replacement Level Fertility
The number of children a couple must have to replace themselves (avgs 2.1 in more developed nations, 2.7 in less developed nations)
World Population
A little over 6billion
Demographic Transition Model
Ok
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 rates, 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 Us
4 Indonesia
Low Status of Women
Most important factor keeping population growth rates high
Method 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-PointSource
(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 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 progress.
BOD
Biological Oxygen Demand, amount of dissolved oxygen needed by aerobic decomposers to break down organic materials
Eutrophication
Rapid algal growth (algal bloom) caused by an excess of nitrogen and phosphorus, blocks sunlight, causing the death/decomposition of aquatic 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 inti law in 1975, established fuel efficiency standards for passenger cars and light trucks. The fuel economy rating a manufacturer’s entire line of passenger cars must currently average at least 27.5 mpg for the manufacturer to comply with the standard
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 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.
Ozone
Secondary pollutant, NO2 +UV~>NO+O; O2~> O3, with VOC’s. Causes respiratory irritation and plant damage. Reduced by reducing NO emissions and VOC’s
Sulfur oxides
(SOx) primary source coal burning. Primary n secondary effects include acid deposition, respiratory irritation, plant damage. Reduction methods include: scrubbers, burn low sulfur fuel
Carbon Dioxide
(CO2) sources include the combustion of fossil fuels. Effects: greenhouse gas-contributes to global warming. Reduction accomplished by increAsed fuel efficiency (gas mileage) mass transit (reduction)
Photochemical Smog
Formed by chemical reactions involving sunlight (NO, VOC, O2)
Acid deposition
Causes by sulfuric and nitric acids resulting resulting in lowered pH of surface waters
Greenhouse Gases
Most significant H2O CO2 methane (CH4) CFC’s. trap outgoing infrared energy (heat)causing earth to warn
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 CFC’s, methyl chloroform, carbon tetrachloride, halon, methyl bromide all of which attack stratospheric ozone. Negative effects of ozone depletion include increased UV, skin cancer cataracts, and decreased plant growth
Municipal Solid Waste
is mostly paper and mostly put into landfills
Sanitary Landfill
problems include: leachate, which is solved usinfg liner with a colection system; methane gas, which may be collected and burned; and volume of garbage, which may be compacted and are/or reduced
incineration
advantages-volume waste reduced by 90% and waste heat can be used. Disadvantages-tpxic emissions (polyviny chloride, dioxin), scrubber and electrostatic precipitators needed. ash disposal.
Best soulution for waste problem
reduce amount of waste at the source
Brownfield
abandoned industrial sites
Keystone Species
species who role an ecosystem is more important than others.
Indictaor Species
species that serve as early warnings than an ecosysten is being damanged.
In Natural Ecosystem
50-90% of pest species are kept under control by: predators, diseases, parasites.
Major Insecticide Groups
clorinated hydrocarbons—- ex DDT; organophosphates— ex malathion; carbamates– ex aldicarb
Pesticide Pros
saves lives from insecttransmitted diseases. increases food supply, and increases prohits for farmers. Cons: genetic resistance, ecosystem imbalance, pesticide treamill, persistence, bioaccumilation and biological magnification.
Natural Pest Control
better agricultural practices, genetically resisitant plants, natural enemies, and biopesticides, sex attractants
Genetically Modified Organisms (GMO’s)
new organisms created by altering the genetic material (DNA) of existing organisms; usually in an attempt to remove undesireable or create desireable characteristics in the new organism.
Electricity Generation
steam, from water boiled fossil fuels or nuclear energy, or falling water is used to turn a generation.
Petroleum (Crude Oil) Formation
microscopic aquatic organisms in sendiments 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 substences, 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 coal, anthracite coal
Nuclear Reactor
consists of a core, control rods, moderator, steam generator, turnbine, containment building.
Alternate Energy Sources
Wind, solar, waves, biomass, geothermal, fuel cells.
Remediation
return a cintaminated area into it’s original state.
LD-50
the amount of chemical that kills 50% of the animals in the test population
Troposphere
first layer of atmosphere 0-10 miles above the Earth’s surface, Contains weather, greenhouse gases (bad ozone)
Stratosphere
second layer of atmosphere 10-30 miles above Earth’s surface. Contains protective ozone layer (good layer)
Inversion Layer (Temperate Inversion)
a warm layer of air above a cooler layer of traps pollutants close to the Earth’s surface
Mutagen
substances that causes changes in DNA; may result in herediatry changes
Teratogen
substances that cause fetus deformities (birth defects)
Carcinogen
substances that cause cancer
Dioxin
one of the most toxic human-made chemicals. Stable, long-lived, by product of herbicide production enters environment as fallout from the incineration of municipal and medical waste and persists for years
PCB’s (Polychlorinated Biphenyls)
Sable, lon-lived, carcinogenic chlorinated hydrocarbons. Produced by the electronics industry.
Multible Use Public Lands
National Forest and National Resource lands
Moderately Restricted Use Public Lands
National Wildlife Refuges
Divergent Plate Boundaries
tectonic plates spreading apart, new crust being 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 at convergant plate boundaries.
Transform Fault
tectonic plates sliding past one another (ex San Andreas fault)
