Environ Science Test 3

What is the current global population mentioned in the paragraph?

More than 7.7 billion

Which country's restrictive governmental policies are mentioned as an example to avoid?

China

What is the preferred method to slow human population growth according to the paragraph?

Establishing societal conditions that lead people to desire fewer children

Restrictive governmental policies

Policies that limit personal freedoms, such as China's former one-child policy, to control population growth.

Societal conditions

The social, economic, and cultural factors that influence people's behaviors and decisions.

By what year is the global population expected to reach nearly 10 billion?

2050

What is India's current population growth rate?

1.5%

In what context do humans exist according to the principles of demography?

Within our environment as one species out of many

Population Ecology

A branch of biology that studies the factors affecting population size and composition in the natural world.

birth control

The effort to control the number of children one bears, particularly by reducing the frequency of pregnancy.

contraception

The deliberate attempt to prevent pregnancy despite sexual intercourse.

demographer

A social scientist who studies the size; density; distribution; age structure; sex ratio; and rates of birth, death, immigration, and emigration of human populations.

demographic fatigue

An inability on the part of governments to address overwhelming challenges related to population growth.

demographic transition

A theoretical model of economic and cultural change that explains the declining death rates and birth rates that occurred in Western nations as they became industrialized. The model holds that industrialization caused these rates to fall naturally by decreasing mortality and by lessening the need for large families. Parents would thereafter choose to invest in quality of life rather than quantity of children.

demography

A social science that applies the principles of population ecology to the study of statistical change in human populations.

family planning

The effort to plan the number and spacing of one's children to offer children and parents the best quality of life possible.

industrial stage

The third stage of the demographic transition model, characterized by falling birth rates that close the gap with falling death rates and reduce the rate of population growth.

infant mortality rate

The number of deaths of infants under 1 year of age per 1000 live births in a population.

IPAT model

A formula that represents how humans’ total impact (I) on the environment results from the interaction among three factors: population (P), affluence (A), and technology (T).

post-industrial stage

The fourth and final stage of the demographic transition model, in which both birth and death rates have fallen to a low level and remain stable there, and populations may even decline slightly.

pre-industrial stage

The first stage of the demographic transition model, characterized by conditions that defined most of human history. In pre-industrial societies, both death rates and birth rates are high.

rate of natural increase

The rate of change in a population’s size resulting from birth and death rates alone, excluding migration.

replacement fertility

The total fertility rate (TFR) that maintains a stable population size.

reproductive window

The portion of a woman’s life between sexual maturity and menopause during which she may become pregnant.

total fertility rate

(TFR) The average number of children born per female member of a population during her lifetime.

transitional stage

The second stage of the demographic transition model, which occurs during the transition from the pre-industrial stage to the industrial stage. It is characterized by declining death rates but continued high birth rates. See also post-industrial stage.

What crop is commonly associated with the clothes we wear?

Cotton

Why is it important to recognize where our food and fiber come from?

Because our lives depend directly on agriculture

What can we do to make our production of food and fiber more sustainable?

Devise ways to reduce the environmental impacts of agriculture and conserve the resources and processes that support it.

bedrock

The continuous mass of solid rock that makes up Earth’s crust.

clay

Sediment consisting of particles less than 0.002 mm in diameter.

erosion

The removal of material from one place and its transport to another by the action of wind or water.

fertilizer

A substance that promotes plant growth by supplying essential nutrients such as nitrogen or phosphorus.

humus

A dark, spongy, crumbly mass of material made up of complex organic compounds, resulting from the partial decomposition of organic matter.

industrial agriculture

Agriculture that uses large-scale mechanization and fossil fuel combustion, enabling farmers to replace horses and oxen with faster and more powerful means of cultivating, harvesting, transporting, and processing crops. Other aspects include large-scale irrigation and the use of inorganic fertilizers. Use of chemical herbicides and insecticides reduces competition from weeds and herbivory by insects.

inorganic fertilizer

A fertilizer that consists of mined or synthetically manufactured mineral supplements. Inorganic fertilizers are generally more susceptible than organic fertilizers to leaching and runoff and may be more likely to cause unintended off-site impacts.

intercropping

Planting different types of crops in alternating bands or other spatially mixed arrangements.

land degradation

A general deterioration of land that diminishes its productivity and biodiversity, impairs the functioning of its ecosystems, and reduces the ecosystem services the land can offer us.

leaching

The process by which minerals dissolved in a liquid (usually water) are transported to another location (generally downward through soil horizons).

loam

Soil with a relatively even mixture of clay-, silt-, and sand-sized particles.

colony collapse disorder

A mysterious malady afflicting honeybees, which has destroyed roughly one-third of all honeybees in the United States annually in recent years. Likely caused by chemical insecticides, pathogens and parasites, habitat and resource loss, or combinations of these factors.

compost

A mixture produced when decomposers break down organic matter, such as food and crop waste, in a controlled environment.

Conservation Reserve Program

U.S. policy in farm bills since 1985 that pays farmers to stop cultivating highly erodible cropland and instead place it in conservation reserves planted with grasses and trees.

conservation tillage

Agriculture that limits the amount of tilling (plowing, disking, harrowing, or chiseling) of soil.

contour farming

The practice of plowing furrows sideways across a hillside, perpendicular to its slope, to help prevent the formation of rills and gullies. The technique is so named because the furrows follow the natural contours of the land.

crop rotation

The practice of alternating the kind of crop grown in a particular field from one season or year to the next.

deposition

The arrival of eroded soil at a new location.

desertification

A form of land degradation in which more than 10% of a land’s productivity is lost due to erosion, soil compaction, forest removal, overgrazing, drought, salinization, climate change, water depletion, or other factors. Severe desertification can result in the expansion of desert areas or creation of new ones.

Dust Bowl

An area that loses huge amounts of topsoil to wind erosion as a result of drought and/or human impact. First used to name the region in the North American Great Plains severely affected by drought and topsoil loss in the 1930s. The term is now also used to describe that historical event and others like it.

monoculture

The uniform planting of a single crop over a large area. Characterizes industrial agriculture.

no-till

Agriculture that does not involve tilling (plowing, disking, harrowing, or chiseling) the soil. The most intensive form of conservation tillage.

organic fertilizer

A fertilizer made up of natural materials (largely the remains or wastes of organisms), such as animal manure, crop residues, charcoal, fresh vegetation, and compost.

overgrazing

The consumption by too many animals of plant cover, impeding plant regrowth and the replacement of biomass. Overgrazing can worsen damage to soils, natural communities, and the land’s productivity for further grazing.

parent material

The base geologic material in a particular location.

pollination

The process by which male sex cells of a flowering plant (pollen) fertilize female sex cells of a flowering plant (ova, or egg cells). This may occur by wind, or it may result from a plant-animal interaction in which one organism (e.g., a bee or a hummingbird) transfers pollen from flower to flower.

polyculture

The planting of multiple crops in a mixed arrangement or in close proximity. An example is some traditional Native American farming that mixed maize, beans, squash, and peppers.

precision agriculture

The use of technology to precisely monitor crop conditions, crop needs, and resource use to maximize production while minimizing waste of resources.

salinization

The buildup of salts in surface soil layers.

sand

Sediment consisting of particles 0.005–2.0 mm in diameter.

seed bank

A storehouse for samples of seeds representing the world’s crop diversity.

shelterbelt

A row of trees or other tall perennial plants that are planted along the edges of farm fields to break the wind and thereby minimize wind erosion.

silt

Sediment consisting of particles 0.002–0.005 mm in diameter.

slash-and-burn

A mode of agriculture frequently used in the tropics in which natural vegetation is cut and then burned, adding nutrition to the soil, before farming begins. Generally farmers move on to another plot once the soil fertility is depleted.

soil

A complex plant-supporting system consisting of disintegrated rock, organic matter, air, water, nutrients, and microorganisms.

soil degradation

A deterioration of soil quality and decline in soil productivity, resulting primarily from forest removal, cropland agriculture, and overgrazing of livestock.

soil horizon

A distinct layer of soil.

soil profile

The cross-section of a soil as a whole, including all soil horizons from the surface to the bedrock.

sustainable agriculture

Agriculture that can be practiced in the same way and in the same place far into the future. Sustainable agriculture does not deplete soils faster than they form, nor does it reduce the clean water, genetic diversity, pollinators, and other resources essential to long-term crop and livestock production.

terracing

The cutting of level platforms, sometimes with raised edges, into steep hillsides to contain water from irrigation and precipitation. Terracing transforms slopes into series of steps like a staircase, enabling farmers to cultivate hilly land while minimizing their loss of soil to water erosion.

topsoil

That portion of the soil that is most nutritive for plants and is thus of the most direct importance to ecosystems and to agriculture. A soil horizon also known as the A horizon.

traditional agriculture

Agriculture in which human and animal muscle power, along with hand tools and simple machines, performs the work of cultivating, harvesting, storing, and distributing crops.

waterlogging

The saturation of soil by water, in which the water table is raised to the point that water bathes plant roots. Waterlogging deprives roots of access to gases, essentially suffocating them and damaging or killing the plants.

weathering

The process by which rocks and minerals are broken down, turning large particles into smaller particles. Weathering may proceed by physical, chemical, or biological means.

What is the projected global population by the middle of this century?

Nearly 10 billion

By 2050, for every four people living today, how many people will there be?

Five

What is a major challenge mentioned in the paragraph regarding the future?

Feeding more than 2 billion additional mouths

What will be required to feed the growing population while protecting natural resources?

More sustainable farming and grazing practices

How many additional people are expected to be living in 2050 compared to today?

More than 2 billion

Sustainable farming practices

Agricultural methods that protect natural resources and are capable of being maintained over the long term

Natural resources

Materials or substances such as water, minerals, forests, and fertile land that occur in nature and can be used for economic gain

What major shift in human history occurred around 10,000 years ago that changed food production?

The domestication of plants and animals

What practice led to the creation of crops with large and flavorful produce?

Selective breeding

How did the advent of agriculture affect human settlements?

It led to more permanent camps and villages

What was one consequence of the ability to grow excess produce?

Development of professional specialties and commerce

What has industrial agriculture introduced to boost food production?

Advanced technology and mechanized approaches

What has been a key factor in increasing agricultural yields in the past century?

Use of fossil fuels and synthetic fertilizers

Approximately how many years ago did humans begin to domesticate plants and animals?

About 10,000 years ago.

Selective Breeding

The process of breeding plants and animals for particular genetic traits.

Industrial Agriculture

A form of modern farming that refers to the industrialized production of livestock, poultry, fish, and crops using advanced technology, mechanization, and synthetic inputs.

Traditional Agriculture

Farming that relies on human and animal muscle power, hand tools, and simple machines, often producing just enough food for subsistence.

aquaculture

The cultivation of fish, shrimp, algae, or other aquatic organisms for food in controlled environments.

Bacillus thuringiensis

(Bt) A naturally occurring soil bacterium that produces a protein that kills certain insects. A common means of controlling crop pests. Its genes have been engineered into some crop plants.

biological control

Control of pests and weeds with organisms that prey on or parasitize them rather than with chemical pesticides. Commonly called biocontrol.

community-supported agriculture

(CSA) A system in which consumers pay farmers in advance for a share of their yield, usually in the form of weekly deliveries of produce.

feedlot

A huge indoor or outdoor pen designed to deliver energy-rich food to animals living at extremely high densities. Also called a factory farm or concentrated animal feeding operation.

food security

The guaranteed availability of an adequate, safe, nutritious, and reliable food supply to all people at all times.

gene editing

An array of new methods allowing scientists in the lab to change particular stretches of DNA in the genome of a target organism in order to express desirable traits in the organism. More targeted and direct than recombinant DNA technology. CRISPR is one common method. Also called genome editing.

genetic engineering

Any process scientists use to manipulate an organism’s genetic material in the lab by adding, deleting, or changing segments of its DNA.

genetically modified (GM) food

Food derived from a genetically modified organism. Often abbreviated as GM food.

Green Revolution

An intensification of the industrialization of agriculture in the developing world in the latter half of the 20th century that dramatically increased crop yields produced per unit area of farmland. Practices include devoting large areas to monocultures of crops specially bred for high yields and rapid growth; heavy use of fertilizers, pesticides, and irrigation water; and sowing and harvesting on the same parcel of land more than once per year or per season.