AP Environmental Science Comprehensive Study Guide NOT A SUBSTITUTE FOR CLASS NOTES

260 Pages·2013·9.53 MB·English

AP Environmental Science
Comprehensive Study Guide

NOT A SUBSTITUTE FOR CLASS
NOTES
(Some Info May Be Repetitive)
APES Exam Topic Outline

I. Earth Systems and Resources (10-15%)
A. Earth Science Concepts (Geologic time scale; plate tectonics, earthquakes, volcanism; seasons;
solar intensity and latitude)
B. The Atmosphere (Composition; structure; weather and climate; atmospheric circulation and
the Coriolis Effect; atmosphere-ocean interactions; ENSO)
C. Global Water Resources and Use (Freshwater/saltwater; ocean circulation; agricultural,
industrial, and domestic use; surface and groundwater issues; global problems; conservation)
D. Soil and Soil Dynamics (Rock cycle; formation; composition; physical and chemical
properties; main soil types; erosion and other soil problems; soil conservation)

II. The Living World (10-15%)
A. Ecosystem Structure (Biological populations and communities; ecological niches; interactions
among species; keystone species; species diversity and edge effects; major terrestrial and aquatic
biomes)
B. Energy Flow (Photosynthesis and cellular respiration; food webs and trophic levels; ecological
pyramids)
C. Ecosystem Diversity (Biodiversity; natural selection; evolution; ecosystem services)
D. Natural Ecosystem Change (Climate shifts; species movement; ecological succession)
E. Natural Biogeochemical Cycles (Carbon, nitrogen, phosphorus, sulfur, water, conservation of
matter)

III. Population (10-15%)
A. Population Biology Concepts (Population ecology; carrying capacity; reproductive strategies;
survivorship)
B. Human Population
1. Human population dynamics (Historical population sizes; distribution; fertility rates;
growth rates and doubling times; demographic transition; age-structure diagrams)
2. Population size (Strategies for sustainability; case studies; national policies)
3. Impacts of population growth (Hunger; disease; economic effects; resource use; habitat
destruction)

IV. Land and Water Use (10-15%)
A. Agriculture
1. Feeding a growing population (Human nutritional requirements; types of agriculture;
Green Revolution; genetic engineering and crop production; deforestation; irrigation;
sustainable agriculture)
2. Controlling pests (Types of pesticides; costs and benefits of pesticide use; integrated
pest management; relevant laws)
B. Forestry (Tree plantations; old growth forests; forest fires; forest management; national
forests)
C. Rangelands (Overgrazing; deforestation; desertification; rangeland management; federal
rangelands)
D. Other Land Use
1. Urban land development (Planned development; suburban sprawl; urbanization)
2. Transportation infrastructure (Federal highway system; canals and channels; roadless
areas; ecosystem impacts)
3. Public and federal lands (Management; wilderness areas; national parks; wildlife
refuges; forests; wetlands)
4. Land conservation options (Preservation; remediation; mitigation; restoration)
5. Sustainable land-use strategies
E. Mining (Mineral formation; extraction; global reserves; relevant laws and treaties)
F. Fishing (Fishing techniques; overfishing; aquaculture; relevant laws and treaties)
G. Global Economics (Globalization; World Bank; Tragedy of the Commons; relevant laws and
treaties)

V. Energy Resources and Consumption (10-15%)
A. Energy Concepts (Energy forms; power; units; conversions; Laws of Thermodynamics)
B. Energy Consumption
1. History (Industrial Revolution; exponential growth; energy crisis)
2. Present global energy use
3. Future energy needs
C. Fossil Fuel Resources and Use
(Formation of coal, oil, and natural gas; extraction/purification methods; world reserves and
global demand; synfuels; environmental advantages/disadvantages of sources)
D. Nuclear Energy (Nuclear fission process; nuclear fuel; electricity production; nuclear reactor
types; environmental advantages/disadvantages; safety issues; radiation and human health;
radioactive wastes; nuclear fusion)
E. Hydroelectric Power (Dams; flood control; salmon; silting; other impacts)
F. Energy Conservation (Energy efficiency; CAFE standards; hybrid electric vehicles; mass
transit)
G. Renewable Energy (Solar energy; solar electricity; hydrogen fuel cells; biomass; wind energy;
small-scale hydroelectric; ocean waves and tidal energy; geothermal; environmental
advantages/disadvantages)

VI. Pollution (25-30%)
A. Pollution Types
1. Air pollution (Sources-primary and secondary; major air pollutants; measurement
units; smog; acid deposition-causes and effects; heat islands and temperature inversions;
indoor air pollution; remediation and reduction strategies; Clean Air Act and other
relevant laws)
2. Noise pollution (Sources; effects; control measures)
3. Water pollution (Types; sources, causes, and effects; cultural eutrophication;
groundwater pollution; maintaining water quality; water purification; sewage
treatment/septic systems; Clean Water Act and other relevant laws)
4. Solid waste (Types; disposal; reduction)
B. Impacts on the Environment and Human Health
1. Hazards to human health (Environmental risk analysis; acute and chronic effects; dose
response relationships; air pollutants; smoking and other risks)
2. Hazardous chemicals in the environment (Types of hazardous waste;
treatment/disposal of hazardous waste; cleanup of contaminated sites; biomagnification;
relevant laws)
C. Economic Impacts (Cost-benefit analysis; externalities; marginal costs; sustainability)

VII. Global Change (10-15%)
A. Stratospheric Ozone (Formation of stratospheric ozone; ultraviolet radiation; causes of ozone
depletion; effects of ozone depletion; strategies for reducing ozone depletion; relevant laws and
treaties)
B. Global Warming (Greenhouse gases and the greenhouse effect; impacts and consequences of
global warming; reducing climate change; relevant laws and treaties)
C. Loss of Biodiversity
1. Habitat loss; overuse; pollution; introduced species; endangered and extinct species
2. Maintenance through conservation
3. Relevant laws and treaties
STANDARD GEOLOGIC TIME SCALE
AGE
EON ERA PERIOD EPOCH IMPORTANT EVENTS
(M.y.)
0.01 -
Holocene Human civilization develops.
present
Quaternary
1.6 - Continental glaciation in the
Pleistocene
0.01 northern hemisphere
Pliocene 5.3 - 1.6 Humans appear for the first time.
23.7 -
Miocene Antarctic Ice Sheet develops.
CENOZOIC 5.3
36.6 -
Oligocene Himalaya Mountains begin to form.
Tertiary 23.7
57.8 -
Eocene The Alps form in Europe.
36.6
66.4 - Mammals become dominant land
Paleocene
57.8 animals
144 - Dinosaurs become extinct; Rocky
Cretaceous
66.4 Mountains begin forming.
208 - Atlantic Ocean begins to form
MESOZOIC Jurassic
144 between N. America & Africa.
PHANEROZOIC
245 - 1st dinosaurs; North America begins
Triassic
208 to separate from Africa.
286 - All land masses joined to form a
Permian
245 single supercontinent called Pangea.
Appalachian Mountains & Ouachita
320 -
Pennsylvanian Mountains formed by continental
286
collision with Africa.
360 - Extensive deposits of coal
Mississippian
320 developed worldwide.
PALEOZOIC 1st fossils of amphibians (animals
Devonian 408-360
which could live on land).
438 -
Silurian 1st fossils of land plants.
408
505 - 1st fossil fish; evidence of
Ordovician
438 continental glaciation in Africa.
545 - Abundant fossils of marine
Cambrian
505 organisms.
PROTEROZOIC PRECAMBRIAN 2500 - 1st evidence of oxygen in
545 atmosphere = 2.0 billion years ago.
Earliest evidence of life = 3.8 billion
4500 - years ago.
ARCHEAN
2500
Earth forms = 4.5 billion years ago.

APES NOTES (Alpabetical by Topic) (Ctrl + F)
Agriculture and Food
NUTRITION & FOOD SUPPLIES
~ although enough food is being produced to feed everyone, it is unevenly distributed
~undernourished: consuming less than enough calories needed for an active, healthy life
~over nutrition: too many calories, a problem in wealthy countries, greatest risk in the US
affects 20% of the world, increases blood pressure, heart attacks, strokes, diabetes
~sub-Saharan Africa: food is becoming scarce (war, poor governments, drought, etc)
~800 million undernourished ~obese:30 lbs over (morbidly- 100 lbs over (5 million Americans)
~60% of Americans are obese (we consume 3500 calories/day)
Chronic Hunger and Food Security
~Undernourishment as a child can lead to stunted growth, mental development, and other disorders. Infectious
diseases like diarrhea that are usually to no concern can become lethal.
~Food Security: ability to obtain sufficient food on a day-today basis, threatened by poverty, women are usually
more effected than men
Other Essential Nutrients
~It is possible to have plenty of calories but still suffer from malnutrition (having a nutritional imbalance, or by
lacking a dietary component)
~Kwashiorkor: a protein deficiency in children, mainly in West Africa, victims have reddish hair, puffy, discolored
skin, and a bloated stomach
~Marasmus: caused by a diet low in calories and protein, the child is thin and shriveled
~Both diseases can cause anemia, lower one's resistance to infections, or cause stunted growth and mental
retardation
~Vitamin A deficiencies can cause blindness, while lack of folic acid causes neurological problems in babies, such
as small heads or no brains
~Anemia: most common dietary deficiency in the world (not enough iron), is a lack of hemoglobin in the blood
~A deficiency of iodine can cause goiter (a swollen thyroid gland) or cause brain damage
Eating a Balanced Diet
~Eating a balanced diet full of grains, fruits, and vegetables, with moderate meat, dairy, and fats will give you all the
nutrients you need
Famines
~Large-scale food shortages, massive starvation, social disruption, economic chaos
~Even if condition improve, it will be hard to recover (they have ruined their resources in order to survive)
~Causes: politics, government failure, adverse weather, insects, war, natural disasters, poverty, political boundaries,
democracies seldom have famines
MAJOR FOOD SOURCES
~Our diet: a dozen grains, 3 root crops, 20 fruits/veggies, 6 mammals, two fowl,
Major Crops
~Mainly wheat, rice, and maize, wheat and rice make up 60% of calories consumed
~Fruits and veggies: have lots of vitamins, minerals, fiber, and complex carbs
Milk, Meat, & Seafood
~N. America, Japan, 7 Europe (20% world population) consume 80% of animal products
~Average American eats 260 lbs/meat/year (Bangladesh-6.5 lbs)
~90% of grain grown is used to feed animals (for slaughter)
~over harvesting, habitat destruction are endangering fisheries: 13/17 gone, with new technology, we can exhaust
entire populations, 70% of fish are declining
1/4 animals are unwanted "by-catch", includes birds and mammals (by lines, drift nets)
~trawl nets can destroy habitats, spawning areas, impossible to rebuild populations
SOIL: A RENEWABLE RESOURCE
~mixture of weathered minerals from rocks, decaying organic material, and living organisms
~with good husbandry, soil can be replenished and renewed
~1/2 of cropland is being destroyed quicker than replaced
Soil Composition
~1/2 mineral (from bedrock/sediments), plant & animal residue, air, water, organisms
~sandy soil: light soil, good drainage, dries quickly vs. clay (tiny particles), heavy, impermeable, holds water longer
~Humus: a sticky, brown residue from decaying plants & animals, gives structure to soil and helps drainage
Soil Organisms
~Topsoil contains millions of organisms, most microscopic (bacteria, algae), worms insects, animals, plant roots
draw up minerals and release acids that decompose particles
~leaf litter creates new organic material
Soil Profiles
~soil horizons: layers of soil, reveal the history, classified by color, texture, composition,
~Horizons make up soil profiles
~Topsoil: A horizon, covered by O horizon (newly deposited material), minerals mixed w/ organic matter, where
most plants spread their roots to absorb nutrients
~subsoil: B horizon, dense with clay and nutrients (soluble)
~C horizon: parent material, weathered rock, weathering allows soil to extend downward
Soil Types
~classified into soil orders by their structure and composition
WAYS WE USE AND ABUSE SOIL
~11% of Earth is used for agriculture
Land Resources
~the average land area available to each individual is decreasing
~ways to improve usage of land: variety, better fertilizers, irrigation, pesticides, labor, water- 95% of agricultural
growth
~forests, plains being converted to farmland, will eventually have to increase output/acre
~some land shouldn't be farmed (more valuable in natural state)- nutrients in the plants, not soil, would result in loss
of biodiversity
Land Degradation
~land destroyed by: 1) humans (buildings, etc) 2) desertification 3) erosion
~in some places, the degradation is so bad that no crops can be supported
~effects: less species, crops, biomass, diversity, vegetation, soil eroded, water runs off
~Causes: 1) water (55%) 2) wind (29%) 3) chemical (12%) 4) physical (4%)
Erosion: The Nature of the Problem
~Importance: redistributed sediments, part of soil formation and loss, sculpts landscapes, creates silt for farming
~However, erosion can destroy topsoil, (exposing the subsoil) reduce land fertility, load rivers with sediments,
smother wetlands, clog water intakes, coat reservoirs with silt
~Erosion equals a 1% loss in cropland/year
Other Agricultural Resources:
water- 73% of all freshwater used for irrigation (15% crops are irrigated world wide)
-80% water irrigated never reach destination (because of evaporation and seepage)
water logging- water-saturated soil causing plants roots to die from lack of oxygen
salinization- when mineral salts accumulate in the soil (particularly occurs when soil in dry climates are irrigated
with saline water)
-when water evaporates, leaves behind lethal salt accumulation for plants
-irrigation problems: 150 million acres worldwide crop land damaged by water logging and salinization.
Water Conservation: greatly reduced problems from excess water use
-makes water available for other uses
Fertilizer- inorganic nutrients
-plants need: nitrogen, potassium, phosphorus, calcium, magnesium and sulfur
-calcium and magnesium limited in areas w/ high rainfall: must be supplied in form of lime (fertilizer)
-lack of nitrogen, potassium and phosphorus also limits plants growth and these elements are added in fertilizers to
enable plant growth
-crop production up since 1950: Nitrate levels in ground water have increased from fertilizers and young children
are sensitive to this and it can be fatal
Alternatives for fertilizer:
-manure and green manure
-nitrogen-fixing bacteria in root nodules of legumes
-interplanting or rotating beans (or other leguminous crop) with other crops (corn, wheat)
Energy: Direct- Fossil fuels supply almost all energy for farming
Indirect-energy synthetic fertilizers, pesticides (agricultural chemicals)- increase in this energy
-food system in U.S.: 16% of total energy use
-more energy put to produce, process and transport than actual farming
-present energy usages unsustainable (need alternatives for future because going to run out)!
New Crops and Genetic Engineering:
-3,000 species of plants have been used for food
-most food only comes from 16 widely grown crops!
-new varieties of crops valuable for humans and good for areas that are limited by climate, soil, pests, etc (harsh
environments)
-ex: winged beans, perennial plants (hot climates), tricale: drought resistant; grows in light, sandy, infertile soil
Green Revolution:
-50 years ago: agricultural research for tropical wheat and rice varieties (for developing countries)
-"miracle" variety- dwarf (Warmon Varlaug) in Mexico
-International Rice Institute in Philippines est. dwarf rice- dramatic increases with these varieties
-green rev. Breeds: "high responders": yield more than other varieties in optimal condition and produce less when
under optimal conditions
Genetic Engineering-
-genetically modified organisms (GMO's) or Frankinsteinian foods!
-have DNA containing genes borrowed from unrelated species.
Ex: "golden rice": gene from daffodil- makes rice produce beta carotene (artificial nutrient in many poor countries).
-genetic engineering also creating new animals
-developed in 1980s
-2000 U.S. Dept of Agriculture reported more than 70 million acres of GM corn, soybeans and other crops planted.
-more than half of all soybeans and cotton and more than 1/4 of corn in the U.S. were GM varieties in the year of
2000
-most of these crops are in the U.S. - Canada and Argentina hold most of these crops outside the U.S.
Positives and Negatives: crops would require less chemicals, be nutrient rich and could withstand harsh conditions
-however, most are resistant to herbicides and can tolerate more chemical use
-some fear that traits will transfer to wild plants creating super, out-of-control weeds
-expensive
Pest Resistance:
-plants created with genes for insecticides
-Bacillus thuringiensis (Bt): bacterium makes toxins lethal to butterfly family and beetle family-
when transformed to crops, protects against these pests
-reduces insecticide spraying
-most Bt crops in North America
-concerns: plants used to perfect conditions and not immune to pests (this natural pesticide is likely to be useless in
the near future, so plants could be in danger in the future)
-effects on non-target species: can kill other species because susceptible and pesticides can travel long distances
-ex: can contaminate milkweeds that monarchs feed on
Weed Control- most popular transgenic crops: tolerates high doses of herbicides
-occupy 3/4 of all genetically engineered acreage
-2 main products: Monsanto's "Round up Ready" (resists glyphosate) and AgrEvo's "Liberty Link" crops (resists
glufosinate).
-exterminates weeds but forces greater amounts of herbicides
-if widespread could create herbicide resistant "super weeds" (genes jump to wild relatives mostly in high
biodiversity regions)
Public Opposition-
public shows concerns for safeness and making rich farmers richer and poor farmers bankrupt
-1999: protestors in India burnt crops suspected of genetic engineering
-objections strong in Europe (esp. Italy)
-2001 European Parliament passed rules requiring strict testing, monitoring and labeling of genetically engineered
food products and seeds. Also banned genes for antibiotic resistance in plants: fear bacteria would become immune
to it.
-potential risks to human health
-2000: StarLink corn only for livestock mixed into corn used in variety of human foods.
Sustainable Agriculture: (regenerative farming)
-aim to produce food and fiber on a sustainable basis and repair the damage caused by destructive practices.
Alternative Methods:
Soil conservation- soil is renewable resource
-most important elements in soil conservation: land management, ground cover, climate, soil type and tillage system
Managing Topography- water runoff downhill causes erosion: contour plowing- leave grass strips in waterways
(plowing across hills, rather than up and down).
-like this is Strip Farming- planting of different kinds of crops in alternating strips along the land contours
-ridges created by cultivation make little dams that trap water to seep into the soil rather than runoff
terracing- shaping the land to create level shelves of earth to hold water and soil: edges of terraces planted with soil,
anchoring plant species
-this is expensive and requires much hand labor (or expensive machines), but makes farming on steep hills possible
perennial species: plants that grow for more than two years- necessary for some crops to protect certain unstable
soils on sloping gradients or watercourses (low areas w/ water runoff)
Ground Cover: protect soil
-cover crops (crop residues)
-interplanting of two different crops (or more) in same field (not only protects but produces double harvest) ex:
beans or pumpkins planted in between corn rows- beans provide nitrogen for corn, pumpkin crowded out weeds and
both crops provided balance of nutrients for corn
-Mulch: manure, wood chips, straw, seaweed, leaves, and other natural products
Reduced tillage: machines just cover seeds so do not disrupt ecosystem
Air
Weather is the day to day fluctuations in the atmosphere while Climate describes temperature and humidity changes
over long periods of time. Climates are not static- they cycle through yearly, centurial (is that a word?) and
millennial patterns.
Initially the climate on Earth was a deadly mixture of Hydrogen, Helium and Methane from the outgassing of
molten rock. 3 billion years ago oxygen was added to our atmosphere with the evolution of photosynthetic
organisms.
Air pressure at sea level 14.5 lbs per square inch known as one Atm. Air pressure decreases with altitude. The
surface of the Earth also experiences low pressure when warm air masses rises due to low density.
Air composition of the Troposphere today:
Nitrogen- 78%
Oxygen- 21%
Traces of Water Vapor, Argon and Carbon dioxide
The Atmosphere has four distinct layers.
Troposphere (roughly 10 km up)
The layer closest to earth. Holds 75% air mass.
Gets colder with altitude
Weather happens here, also only layer with water
Stratosphere
The top of the stratosphere contains ozone- O3
Ozone absorbs high level UV radiation from the sun.
Temperature increases with altitude because of UV absorption
Ozone molecules are broken down by CFC (now outlawed ingredient in aerosol sprays, refrigerator coolants and
electrical cleaning solvents)
Excessive UV light on the Earth causes skin cancer, cataracts and mutates and kills plankton (the ocean's bread
basket).
Mesosphere
Temperature decreases with height
Thermosphere
Highly ionized gas interacts with magnetosphere to create Aurora borealis (Northern Lights)!
Global Energy Transfer- before man (and woman) global energy was in balance.
Most of the energy from the sun is in the high energy wavelengths- UV and visible light.
50% of this energy is absorbed at the surface.
Energy reflected from the surface is infrared (longer wavelengths)
Convection- the transfer of energy of a warm fluid (like gas or water) upwards into a cooler zone. The cycle of air
upwards around and down is called Convection Currents.
Why it rains in a rain forest: The sun's energy is concentrated near the Equator. Rising hot air expands and cools
(called Adiabatic cooling). Colder air can't hold as much moisture so after a certain altitude, the air dumps out its
water vapor in the form of water droplets- the stuff of clouds. Rising air creates low pressure and lots of nasty
weather, unless you are a tropical plant in which case you are very happy. As the water vapor condenses it gives up
latent heat energy- this helps large cloud formations rise higher, cool more and build energy to form large storm
systems like hurricanes.
Why it is dry in a desert: At 30 degrees North and South latitude the air is cooling, becoming more dense and
sinking. Sinking air creates high pressure. High pressure days are cloudless great tanning weather kind of days,
unless you are thirsty.
Global winds are caused by the constant balancing act going on in our atmosphere as moist, warm air travels upward
from the Equator and then cools and sinks at the 30 degree latitude belt. The air rises again at the 60 latitude and
sinks at the poles. When the air moves laterally across the Earth's surface from belt to belt (High to Low pressure) it
creates winds- we live in the Westerly wind belt which is why all of our weather comes from West to East. Below us
are the trade winds which blow towards the Equator.
All wind belts are curved to the rotation of the Earth knows as the Coriolis Effect. In the Northern hemisphere the
air curves to the right. In the south it curves to the left. These curving winds are also partially responsible for the
direction of the major ocean currents of the world.
The Coriolis effect is also what spins tornadoes and cyclones. Cyclones are low pressure centers with winds that
blow inwards in a counterclockwise direction. Weather conditions are very stormy.