6 12 & 13 Flashcards
(110 cards)
1
Q
What is age structure?
A
Percentage of the population at each age level
Age structure indicates the distribution of various age groups in a population.
2
Q
Define crude birth rate.
A
Annual number of live births per 1,000 people in a population
Crude birth rate is measured at the midpoint of a given year.
3
Q
What is the crude death rate?
A
Annual number of deaths per 1,000 people in a population
Crude death rate is also measured at the midpoint of a given year.
4
Q
What does cultural carrying capacity refer to?
A
Limit on population growth allowing reasonable comfort and freedom
It must not impair the ability of the planet to sustain future generations.
5
Q
What is demographic transition?
A
Hypothesis that countries experience declines in death rates followed by declines in birth rates
This typically occurs as countries become industrialized.
6
Q
What is emigration?
A
Movement of people out of a specific geographic area
Compare with immigration and migration.
7
Q
What does family planning involve?
A
Providing information and contraceptives to help choose number and spacing of children
It includes clinical services to assist in these choices.
8
Q
Define fertility rate.
A
Number of children born to an average woman during her lifetime
Compare with replacement-level fertility.
9
Q
What is immigration?
A
Migration of people into a country to take up permanent residence
Compare with emigration and migration.
10
Q
What is the infant mortality rate?
A
Number of babies out of every 1,000 born who die before their first birthday
It is a critical measure of a country’s health system.
11
Q
Define life expectancy.
A
Average number of years a newborn can be expected to live
It is an important indicator of overall health in a population.
12
Q
What is population change?
A
Increase or decrease in the size of a population
It is calculated as (Births + Immigration) – (Deaths + Emigration).
13
Q
Define replacement-level fertility.
A
Average number of children a couple must bear to replace themselves
This average is slightly higher than two children per couple due to child mortality.
14
Q
What is the total fertility rate (TFR)?
A
Estimate of the average number of children born to a woman during her lifetime
It considers age-specific fertility rates for women aged 15–44.
15
Q
What is agroforestry?
A
Planting trees and crops together.
16
Q
What is alley cropping?
A
Planting of crops in strips with rows of trees or shrubs on each side.
17
Q
What is animal manure?
A
Dung and urine of animals used as a form of organic fertilizer.
18
Q
What is aquaculture?
A
Growing and harvesting of fish and shellfish for human use in freshwater ponds, irrigation ditches, and lakes, or in cages or fenced–in areas of coastal lagoons and estuaries or in the open ocean.
19
Q
What is arable land?
A
Land that can be cultivated to grow crops.
20
Q
What is bioaccumulation?
A
An increase in the concentration of a chemical in specific organs or tissues at a level higher than would normally be expected.
21
Q
What is biological amplification?
A
See biomagnification.
22
Q
What is biological pest control?
A
Control of pest populations by natural predators, parasites, or disease–causing bacteria and viruses (pathogens).
23
Q
What is biomagnification?
A
Increase in concentration of DDT, PCBs, and other slowly degradable, fat–soluble chemicals in organisms at successively higher trophic levels of a food chain or web.
24
Q
What is chronic malnutrition?
A
Faulty nutrition, caused by a diet that does not supply an individual with enough protein, essential fats, vitamins, minerals, and other nutrients needed for good health.
25
What is chronic undernutrition?
Condition suffered by people who cannot grow or buy enough food to meet their basic energy needs.
26
What is commercial inorganic fertilizer?
Commercially prepared mixture of inorganic plant nutrients such as nitrates, phosphates, and potassium applied to the soil to restore fertility and increase crop yields.
27
What is compost?
Partially decomposed organic plant and animal matter used as a soil conditioner or fertilizer.
28
What is conservation–tillage farming?
Crop cultivation in which the soil is disturbed little (minimum–tillage farming) or not at all (no–till farming) in an effort to reduce soil erosion, lower labor costs, and save energy.
29
What is contour farming?
Plowing and planting across the changing slope of land, rather than in straight lines, to help retain water and reduce soil erosion.
30
What is conventional–tillage farming?
Crop cultivation method in which a planting surface is made by plowing land, breaking up the exposed soil, and then smoothing the surface.
31
What is DDT?
Dichlorodiphenyltrichloroethane, a chlorinated hydrocarbon that has been widely used as an insecticide but is now banned in some countries.
32
What is desertification?
Conversion of rangeland, rain–fed cropland, or irrigated cropland to desertlike land, with a drop in agricultural productivity of 10% or more. It is usually caused by a combination of overgrazing, soil erosion, prolonged drought, and climate change.
33
What are domesticated species?
Wild species tamed or genetically altered by crossbreeding for use by humans for food (cattle, sheep, and food crops), as pets (dogs and cats), or for enjoyment (animals in zoos and plants in botanical gardens).
34
What is famine?
Widespread malnutrition and starvation in a particular area because of a shortage of food, usually caused by drought, war, flood, earthquake, or other catastrophic events that disrupt food production and distribution.
35
What is a feedlot?
Confined outdoor or indoor space used to raise hundreds to thousands of domesticated livestock.
36
What is fertilizer?
Substance that adds inorganic or organic plant nutrients to soil and improves its ability to grow crops, trees, or other vegetation.
37
What is fish farming?
See aquaculture.
38
What is a fishery?
Concentration of particular aquatic species suitable for commercial harvesting in a given ocean area or inland body of water.
39
What is food insecurity?
Condition under which people live with chronic hunger and malnutrition that threatens their ability to lead healthy and productive lives.
40
What is food security?
Condition under which every person in a given area has daily access to enough nutritious food to have an active and healthy life.
41
What is a fungicide?
Chemical that kills fungi.
42
What is a genetically modified organism (GMO)?
Organism whose genetic makeup has been altered by genetic engineering.
43
What is green manure?
Freshly cut or still–growing green vegetation that is plowed into the soil to increase the organic matter and humus available to support crop growth.
44
What is the green revolution?
Popular term for the introduction of scientifically bred or selected varieties of grain (rice, wheat, maize) that, with adequate inputs of fertilizer and water, can greatly increase crop yields.
45
What is an herbicide?
Chemical that kills a plant or inhibits its growth.
46
What is high–input agriculture?
See industrialized agriculture.
47
What is humus?
Slightly soluble residue of undigested or partially decomposed organic material in topsoil. This material helps retain water and water–soluble nutrients, which can be taken up by plant roots.
48
What is hydroponics?
Form of agriculture in which farmers grow plants by exposing their roots to a nutrient–rich water solution instead of soil.
49
What is industrialized agriculture?
Production of large quantities of crops and livestock for domestic and foreign sale; involves use of large inputs of energy from fossil fuels, water, fertilizer, and pesticides.
## Footnote
Compare subsistence farming.
50
What is inorganic fertilizer?
See commercial inorganic fertilizer.
51
What is an insecticide?
Chemical that kills insects.
52
What is integrated pest management (IPM)?
Combined use of biological, chemical, and cultivation methods in proper sequence and timing to keep the size of a pest population below the level that causes economically unacceptable loss of a crop or livestock animal.
53
What is intercropping?
Growing two or more different crops at the same time on a plot.
## Footnote
For example, a carbohydrate–rich grain that depletes soil nitrogen and a protein–rich legume that adds nitrogen to the soil may be intercropped. Compare monoculture, polyculture.
54
What is leaching?
Process in which various chemicals in upper layers of soil are dissolved and carried to lower layers and, in some cases, to groundwater.
55
What is low–input agriculture?
See sustainable agriculture.
56
What is malnutrition?
See chronic malnutrition.
57
What is manufactured inorganic fertilizer?
See commercial inorganic fertilizer.
58
What is manure?
See animal manure, green manure.
59
What is metabolism?
Ability of a living cell or organism to capture and transform matter and energy from its environment to supply its needs for survival, growth, and reproduction.
60
What is minimum–tillage farming?
See conservation–tillage farming.
61
What is monoculture?
Cultivation of a single crop, usually on a large area of land.
## Footnote
Compare polyculture.
62
What is no–till farming?
See conservation–tillage farming.
63
What is organic agriculture?
Growing crops with limited or no use of synthetic pesticides and synthetic fertilizers; genetically modified crops, raising livestock without use of synthetic growth regulators and feed additives; and using organic fertilizer and natural pest controls.
## Footnote
See sustainable agriculture.
64
What is organic farming?
See organic agriculture and sustainable agriculture.
65
What is organic fertilizer?
Organic material such as animal manure, green manure, and compost applied to cropland as a source of plant nutrients.
## Footnote
Compare commercial inorganic fertilizer.
66
What is overnutrition?
Diet so high in calories, saturated fats, salt, sugar, and processed foods, and so low in vegetables and fruits that the consumer runs a high risk of developing diabetes, hypertension, heart disease, and other health hazards.
## Footnote
Compare malnutrition, undernutrition.
67
What are PCBs?
See polychlorinated biphenyls.
68
What is percolation?
Passage of a liquid through the spaces of a porous material such as soil.
69
What is a pest?
Unwanted organism that directly or indirectly interferes with human activities.
70
What is a pesticide?
Any chemical designed to kill or inhibit the growth of an organism that people consider undesirable.
## Footnote
See fungicide, herbicide, insecticide.
71
What is plantation agriculture?
Growing specialized crops such as bananas, coffee, and cacao in tropical developing countries, primarily for sale to developed countries.
72
What are polychlorinated biphenyls (PCBs)?
Group of 209 toxic, oily, synthetic chlorinated hydrocarbon compounds that can be biologically amplified in food chains and webs.
73
What is polyculture?
Complex form of intercropping in which a large number of different plants maturing at different times are planted together.
## Footnote
See also intercropping. Compare monoculture.
74
What is salinization?
Accumulation of salts in soil that can eventually make the soil unable to support plant growth.
75
What is slash-and-burn agriculture?
Cutting down trees and other vegetation in a patch of forest, leaving the cut vegetation on the ground to dry, and then burning it. The ashes that are left add nutrients to the nutrient-poor soils found in most tropical forest areas. Crops are planted between tree stumps. Plots must be abandoned after a few years (typically 2–5 years) because of loss of soil fertility or invasion of vegetation from the surrounding forest.
76
What is soil?
Complex mixture of inorganic minerals (clay, silt, pebbles, and sand), decaying organic matter, water, air, and living organisms.
77
What is soil conservation?
Methods used to reduce soil erosion, prevent depletion of soil nutrients, and restore nutrients previously lost by erosion, leaching, and excessive crop harvesting.
78
What is 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.
## Footnote
Compare soil conservation.
79
What are soil horizons?
Horizontal zones, or layers, that make up a particular mature soil. Each horizon has a distinct texture and composition that vary with different types of soils.
## Footnote
See soil profile.
80
What is a soil profile?
Cross-sectional view of the horizons in a soil.
## Footnote
See soil horizon.
81
What is strip-cropping?
Planting regular crops and close-growing plants, such as hay or nitrogen-fixing legumes, in alternating rows or bands to help reduce depletion of soil nutrients.
82
What is subsistence farming?
Farming that provides enough food for a farm family’s survival and a surplus that can be sold.
## Footnote
See traditional subsistence agriculture.
83
What is sustainable agriculture?
Method of growing crops and raising livestock based on organic fertilizers, soil conservation, water conservation, biological pest control, and minimal use of nonrenewable fossil-fuel energy.
84
What is terracing?
Planting crops on a long, steep slope that has been converted into a series of broad, nearly level terraces with short vertical drops from one to another that run along the contour of the land to retain water and reduce soil erosion.
85
What is traditional intensive agriculture?
Production of enough food for a farm family’s survival and a surplus that can be sold. This type of agriculture uses higher inputs of labor, fertilizer, and water than traditional subsistence agriculture.
## Footnote
See traditional subsistence agriculture. Compare industrialized agriculture.
86
What is traditional subsistence agriculture?
Production of enough crops or livestock for a farm family’s survival.
## Footnote
Compare industrialized agriculture, traditional intensive agriculture.
87
What are transgenic organisms?
See genetically modified organisms.
88
What is undernutrition?
See chronic undernutrition.
89
What is waterlogging?
Saturation of soil with irrigation water or excessive precipitation so that the water table rises close to the surface.
90
What is a windbreak?
Row of trees or hedges planted to partially block wind flow and reduce soil erosion on cultivated land.
91
What is an aquifer?
Porous, water–saturated layers of sand, gravel, or bedrock that can yield an economically significant amount of water.
92
What is a dam?
A structure built across a river to control the river’s flow or to create a reservoir.
## Footnote
See reservoir.
93
What is desalination?
Purification of salt water or brackish (slightly salty) water by removal of dissolved salts.
94
What is a drainage basin?
See watershed.
95
What is a drought?
Condition in which an area does not get enough water because of lower–than–normal precipitation or higher–than–normal temperatures that increase evaporation.
96
What is a floodplain?
Flat valley floor next to a stream channel. For legal purposes, the term often applies to any low area that has the potential for flooding, including certain coastal areas.
97
What is groundwater?
Water that sinks into the soil and is stored in slowly flowing and slowly renewed underground reservoirs called aquifers; underground water in the zone of saturation, below the water table.
## Footnote
Compare runoff, surface water.
98
What is natural recharge?
Natural replenishment of an aquifer by precipitation, which percolates downward through soil and rock.
## Footnote
See recharge area.
99
What is a recharge area?
Any area of land allowing water to percolate down through it and into an aquifer.
## Footnote
See aquifer, natural recharge.
100
What is reliable runoff?
Surface runoff of water that generally can be counted on as a stable source of water from year to year.
## Footnote
See runoff.
101
What is a reservoir?
Artificial lake created when a stream is dammed.
## Footnote
See dam.
102
What is subsidence?
Slow or rapid sinking of part of the earth’s crust that is not slope–related.
103
What is surface runoff?
Water flowing off the land into bodies of surface water.
## Footnote
See reliable runoff.
104
What is surface water?
Precipitation that does not infiltrate the ground or return to the atmosphere by evaporation or transpiration.
## Footnote
See runoff. Compare groundwater.
105
What is virtual water?
Water that is not directly consumed but is used to produce food and other products.
106
What is a water footprint?
A rough measure of the volume of water that we use directly and indirectly to keep a person or group alive and to support their lifestyles.
107
What is the water table?
Upper surface of the zone of saturation, in which all available pores in the soil and rock in the earth’s crust are filled with water.
## Footnote
See zone of aeration, zone of saturation.
108
What is a watershed?
Land area that delivers water, sediment, and dissolved substances via small streams to a major stream (river).
109
What is the zone of aeration?
Zone in soil that is not saturated with water and that lies above the water table.
## Footnote
See water table, zone of saturation.
110
What is the zone of saturation?
Zone where all available pores in soil and rock in the earth’s crust are filled by water.
## Footnote
See water table, zone of aeration.
