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Worlds most populous nation with 1/5 of all people living on earth

Size of Human Population

6.7 billion people

Worlds population increased the most

most recently

Environmental Impact

According to the IPAT model, technology that enhances our acquisition of minerals, fossil fuels, timber, and ocean fish

Sensitivity Factor

sensitivity of given environments to human impact and for the effects of social institutions such as education, laws, societies, ethical standards.


individuals who study the statistical characteristics of human populations, help predict population dynamics and environmental impacts

3 most populated countries

China, India, United States

Age structure

individuals in young age groups do a great deal of reproduction.. most industrialized nations are aging,

Population Change

An increase or decrease in the size of a population. It is equal to (Births + Immigration) [[minus]] (Deaths + Emigration).

TFR is controlled

social and economic security drive TFR down

replacement-level fertility rate

2.1 births per woman

Factors that affect total TFR

When the TFR drops below 2.1, population size, in the absence of immigration will shrink... medical care, urbanization drives TFR down, social security drives TFR down, women in the labor force drives TFR down.

Demographic Transition

the process by which a country moves from relatively high birth and death rates to relatively low birth and death rates... the decline in death rates followed by decline in birth rates when a country becomes pop growth occurs in period between death rates falling before birth rates

Family-Planning Programs

can effectively lower population growth rates in all types of nations, reduces birth rates through education and increased availability of contraceptives

Industrialized Agriculture

Using large inputs of energy from fossil fuels (especially oil and natural gas), water, fertilizer, and pesticides to produce large quantities of crops and livestock for domestic and foreign sale. Compare subsistence farming.. most characteristic of developed countries

Healthy soil

helps crops produce more food... requires contributions from B. organic material from formerly living material.
C. minerals from the weathering of the C horizon.
D. the millions of living organsims in the soil.
E. complex organic molecules resulting from decomposition.

Soil Erosion

Movement of soil components, especially topsoil, from one place to another, usually by wind, flowing water, or both. This natural process can be greatly accelerated by human activities that remove vegetation from soil.

Causes of Soil Erosion

overcultivating, overgrazing, clearing forests, removing plant cover


The loss of more than 10% productivity in arid areas due to erosion, soil compaction, forest removal, and an array of other factors (overgrazing, drought, salinzation, climate change, depletion of water)

National Resources Conservation Service

provides technical assistance to both farmers and ranchers... a conservation leader for all natural resources, ensuring private lands are conserved, restored, and more resilient to environmental challenges, like climate with landowners through conservation planning and assistance designed to benefit the soil, water, air, plants, and animals that result in productive lands and healthy ecosystems.

Crop Rotation

the system of growing a different crop in a field each year to preserve the fertility of the land.. controls erosion and helps replenish soil nutrients

Contour farming

Plowing and planting across the changing slope of land, rather than in straight lines, to help retain water and reduce soil erosion.


shaping the land to create level shelves of earth to hold water and soil; requires extensive hand labor or expensive machinery, but it enables farmers to farm very steep hillsides


Growing two or more different crops at the same time on a plot. For example, a carbohydrate-rich grain that depletes soil nitrogen and a protein-rich legume that adds nitrogen to the soil may be intercropped.


soil protection provided by rows of planted vegetation between strips

No-till farming

cuts furrows through the topsoil and crop residue, drops seeds into furrow, and closes the furrow over the seeds.. then add a localized dose of fertilizer


Process that occurs when soils in arid areas are brought under cultivation through irrigation. In arid climates, water evaporates quickly off the ground surface, leaving salty residues that render the soil infertile., the process in which soil becomes saltier and saltier until, finally, the salt prevents the growth of plants. Salinization is caused by irrigation because salts brought in with the water remain in the soil as water evaporates.

food supply problem

food security depends on maintaining healthy soil, water, and biodiversity.


farming strategy in which large fields are planted with a single crop, year after year... gains efficiency of scale

green revolution

the introduction of pesticides and high-yield grains and better management during the 1960s and 1970s which greatly increased agricultural productivity....increased crop output per unit area of existing cultivated land... Negative effects include the intensive use of water, fossil fuels, inorganic fertilizers, pesticides made pollution worse, erosion.. also reduced biodiversity, decline in soil quality

Biological control

A method of pest control that involves the use of naturally occurring disease organisms, parasites, or predators to control pests, a natural predator or disease released into an area to combat a pest insect

Integrated Pest Management

a variety of pest control methods that include repairs, traps, bait, poison, etc. to eliminate pests.. biocontrol measures, crop rotation, habitat diversification

Insects and agriculture

usually essential pollinators and predators for successful agriculture

Genetically Modified Organisms

crops that carry new traits that have been inserted through advanced genetic engineering methods, organisms whose genetic code has been altered by artificial means such as interspecies gene transfer

Seed banks

holds and preserves hundreds of plants that are going extinct.. protects genetic diversity


allow for greater production of food, but can emit strong odors and pollute surface water and groundwater because livestock produce prodigious amounts of feces and urine


can bring economic benefits and food security to many developing regions , the science and business of raising and harvesting fish in a controlled situation

Most energy efficient foods

energy is lost from one animal to another, vegetarian diet must more energy efficient than eating meat.. eggs chicken and milk good choices... cattle the worse (beef)

Organic Agriculture

crops produced without the use of synthetic or industrially produced pesticides and fertilizers, Approach to farming and ranching that avoids the use of herbicides, pesticides, growth hormones, and other similar synthetic inputs.

Sustainable agriculture

Farming methods that preserve long-term productivity of land and minimize pollution, typically by rotating soil- restoring crops with cash crops and reducing in-puts of fertilizer and pesticides.

How to name an organism

categories meant to reflect evolutionary relationships. related species grouped together into genera, related genera grouped into families..every species has two part latin name denoting genus and species.. third part of the name is subspecies


the diversity of plant and animal life in a particular habitat (or in the world as a whole), the variety of species living within an ecosystem.... he genetic diversity within and between populations of a species.

Global biodiversity patterns

species richness generally increase as one approaches the equator ( pattern of variation with latitude called the latitudinal gradient). species diversity tends to increase with diversity of habitats

Mass extinction

event in which many types of living things become extinct at the same time

Background extinction

Normal extinction of various species as a result of changes in local environmental conditions. Compare mass depletion, mass extinction., the gradual process of species becoming extinct

Changes species diversity globally

speciation and extinction

Recent extinction rates

species loss is accelerating as our population growth and resource consumption put increasing strain on habitats and wildlife.

Red list

an updated list of species facing high risks of extinction to keep track of the current status of endangered species... , categorise species at risk

Biodiversity loss

the decline in population sizes of many organisms which are accompanied by shrinkage of species geographic ranges. 4 primary causes: habitat alteration, invasive species, pollution, and overharversting.. global climate change becoming the 5th (habitat destruction, the introduction of invasive species, and overexploitation)

invasive species

gypsy moth, european starling, cheatgrass, brown tree snake, kudzu, asian long horned beetles, rosy wolfsnail, european rabbits

Species loss on humans

species have ecological, economic, medical, scientific, and intrinsic value

threatened species

California condor and whooping crane

Equilibrium Theory of Island Biogeography

theory that says species richness on islands can be modeled as a dynamic balance between colonization by species and extinction of species, the theory that the biodiversity on islands is governed by rates of colonization and extinction, which in turn are controlled by island isolation and island size (he number of species increases with the size of the island; all else being equal, larger islands contain more species (correct answer)

Endangered Species Act

. is one of the world's toughest environmental laws.
B. allows the use of endangered species for approved scientific purposes or if the use enhances the survival of the species.
C. authorizes identification of endangered species solely on a biological basis.
D. requires all commercial shipments of wildlife enter or leave the U.S. through one of nine designated ports.
-dictates that landowners can harm species only if they improve habitat for the species in other areas

umbrella species

need large areas of undisturbed habitat, a species that impacts the survival of many species


tries to prevent the extinction of species by asking countries to stop the importation of organisms or parts of organisms (like tiger bones) if they are endangered species

biodiversity hotspots

A relatively small area with an exceptional concentration of endemic species (map in book p.181)

Urban growth boundary

geographical boundaries placed around a city to limit suburban growth within that city, is intended to provide guidelines for future city development

U.S. Population shift

shifting to the south and the west

Urban populations are changing

urban areas are spreading outward in what is called sprawl.


Development of new housing sites at relatively low density and at locations that are not contiguous to the existing built-up area.

Suburb problems

suburbs allot more space to each person and has spread human impact across the landscape.. natural areas gone due to housing developments, roads to drive everywhere and more pollution

New urbanism

Outlined by a group of architects, urban planners, and developers from over 20 countries, an urban design that calls for development, urban revitalization, and suburban reforms that create walkable neighborhoods with a diversity of housing and jobs.

sustainability of cities

use renewable energy sources, mass transit and recycle materials...ustainable uses for different areas of the city is city planners first priority

Sprawl impact

forces people to drive cars, increased pollution due to transportation, promotes physical inactivity, more land is developed, drains tax dollars and puts into new developments, (trans, pollution, health, land use, economics)

Resource Management

the sustainable use of natural resources is the goal

Maximum Sustainable Yields

The population size that yields maximum production that allows the population to be sustained indefinitely without decreasing its ability to provide the same level of production.... cut trees shortly after fastest stage of growth.. keep fish at intermediate levels just like trees

Forest greatest ecological complexity

they are mature and exhibit a multi-level canopy

Ecosystem services provided by forest

structural complexity and their ability to provide many niches for organisms... provide habitat and help maintain soil, air, and water quality.... Ecosystem services include forest vegetation, plants help regulate the hydrolic cycle, plants store carbon and release oxygen, provide people with wood


has the greatest impacts in tropical areas and arid regions... forest cut down for population expansion

Reasons not to restrict logging

desperate enough for economic development, logging gives jobs

secondary forest

trees that sprouted after old growth timber was cut

Forestry practices that conserve biodiversity

using a selection system to get uneven-aged stands .. definitely not clear cutting

National Forest Management Act

was passed in 1976 with the intent to ensure multiple use and sustainable yield of commercial forests

Forests Restoration Act

directs timber companies to remove small trees, underbrush, and dead trees to reduce fires in

Fires important to forests

fire important to function and biodiversity.

Wilderness areas

off limits to development but they are open to hiking, nature study, and other low impact public recreation. Necessary to assure that an increasing population, accompanied by expanding settlement and growing mechanization, does not occupy and modify all areas with the U.S.. can hunt in national parks

land trust

private nonprofit groups , a local or regional organization that purchases land valued by its members, with the aim of preserving it in its natural condition

how water contaminates effect aquatic organisms

most chemicals are water soluble so they enter these organisms through drinking or skin absorption

physical hazard

earthquakes, volcanic, fires, floods, blizzard, landslides, hurricanes, and droughts

chemical hazard

synthetic chemicals that our society produces such as disinfectants, pesticides, chemicals produced naturally by organisms can also be hazardous

biological hazard

virus, bacterial infection, infectious diseases such as malaria, cholera, tuberculosis, influenza.. organisms transmit disease

cultural hazard

smoking, drugs, diet, unsafe sex

Most significant cause of death


3 top deaths in U.S.

diseases of heart, cancer, stroke

indoor pollutants

adon, cigarette smoke, asbestos and lead, dust, toxicants in plastics and consumer products


one who studies the nature and effects of poisons and their treatment, study the effects of chemical agents suspected to be harmful

pesticide drift

chemical substances can be transported by air, effects can occur far from the site of direct chemical use


the selective absorption and concentration of molecules by cells, the gradual build-up of synthetic and organic chemicals in living organisms


Increase in concentration on certain stable chemicals in successively higher trophic levels of a food chain., the process by which the concentration of toxic substances increases in each successive link in the food chain.


because it contributed to the near extinction of birds, including the bald eagle and the peregrine falcon. DDT is a persistent chemical that becomes concentrated in animal tissues, rising in concentration in animals that are higher in the food chain. It is particularly toxic to fish, aquatic invertebrates and insects (including some that are beneficial).

dose-response curves

show the effects of various doses of toxic agents on a group of test organisms.

LD 50

the amount of a chemical that kills 50% of the animals in a test population, the single dose of a substance at which 50% of the test animals die

acute exposure

(short-term, intense) Burns. Radiation sickness.

chronic exposure

low amounts of contact with a toxicant over long periods of time

synergistic effects

often have effects that are multiplicative, When the effects of two factors working together have more impact than either would working alone

calculated risk

a chance that a person takes after carefully considering all possible outcomes

percieved risk

the anxieties felt because the consumer cannot anticipate the outcomes of a purchase but believes there might be negativve consequences


Pesticides in the United States are registered through the, an independent federal agency established to coordinate programs aimed at reducing pollution and protecting the environment

Toxic Substance Control Act

EPA tracks 75,000 chemicals. May ban chemicals that pose unreasonable risk.

4 stages of demographic transition

stable preindustrial stage, transitional stage, industrial stage, stable postindustrial stage

the preindustrial stage

birth and death rates are high during

red list

a record of current species facing unusually high risks of extinction

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