Chapter 14 Flashcards
polyculture
planting a mix of perennial grasses, legumes, sunflowers, grain crops and plants that provides natural insecticides in the same field. (many different plants maturing at various time are planted together.)
- less need for fertilizers and water
- more protection to the plants from wind and water erosion
- little to no need for insecticides and herbicides
perennials
plants that have more than a two year life cycle
-less labor, reduces soil erosion and less polution
annuals
plants that have a one year life cycle
industrialized agriculture (high-input agriculture)
- 80% of world’d food supply
- uses large amounts of fossil fuels, water, commercial fertilizers and pesticides to produce a single crop (monocultures) or livestock
plantation agriculture
- form of industrialized agriculture
- used on developing countries growing cash crops (soybeans, coffee, sugarcane, cocoa, vegetables, bananas)
traditional subsistence agriculture
- mostly draft animals and human labor
- it only produces enough for a farm family’s survival
Traditional intensive agriculture
-high inputs of human labor, draft labor, water, and fertilizers in order to get a higher yield per area of cultivated land
green revolution
- 1950
- new management techniques and mechanization as well as more fertilization and irrigation
- improved crop varieties and increased food production
second green revolution
- 1967-present day
- introducing fast growing varieties of rice and wheat in several developing countries
interplanting
- growing several different crops on the same plot
- reduces the chances of losing food supplies due to pests, bad weather and other misfortunes.
polyvarietal cultivation
planting a plot with several varieties of the same crop
intercropping
growing two or more different crops at the same time on a plot
agroforestry (alley cropping)
crops and trees are planted in alternate rows
land degradation
natural or human processes decrease the future ability of land to support crops, livestock or wild species
soil erosion
-the movement of soil components (surface litter or topsoil) from one place to another.
main causes: flowing water and wind
harmful effects: loss of soil fertility and sediments pollute water
desertification
the productive potential of arid or semi-arid land falls by 10% or more because of natural climate change and human activities
salinization
- when the small amts. of salts in irrigation water become highly concentrated on the soil surface through evaporation.
- stunts crop growth, lowers crop yields and eventually kills plants and ruins the land
waterlogging
when the soil remains under water for a prolonged periods of time, which impairs root growth due to decreased oxygen levels.
soil conservation
-using ways to reduce soil erosion and restore soil fertility
conventional-tillage farming
farmers plow the land and then break up and smooth the soil to make a planting surface
conservation-tillage farming
the soil is disturbed little or not at all to reduce soil erosion, lower labor costs, and save energy
terracing
can reduce soil erosion on steep slope by converting the land into a series of broad, nearly level terraces that run across the land contour
contour farming
involves plowing and planting crops in rows across the slope of the land rather than up and down
strip cropping
planting alternating strips of a row crop and another crop that completely covers the soil
cover crops
the planting of cops such as alfalfa, clover, or rye immediately after harvest to help protect and hold the soil
windbreaks (shelter belts)
row of trees or hedges to partially block wind flow and reduce soil erosion on cultivated land
organic fertilizer
organic material such as animal manure, green manure, and compost, applied to cropland as a source of plant nutrition
commercial inorganic fertilizer
commercially prepared mixture of plant nutrients such as nitrates, phosphates, and potassium applied to the soil to restore fertility and increase crop yields
animal manure
dung and urine of animals used as a form of organic fertilizer
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
compost
partially decomposed organic plant and animal matter used as a soil conditioner or fertilizer
crop rotation
Planting a field, or an area of a field, with different crops from year to year to reduce soil nutrient depletion.
chronic undernutrition
An ongoing condition suffered by people who cannot grow or buy enough food to meet their basic energy need
malnutrition
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
over nutrition
diet so high in calories, saturated fats, sugar, salt, and processed foods and so low in vegetables and fruits that the consumer runs high risks of diabetes, hypertension, heart disease, and other health hazards
third green revolution
- a gene revolution
- using genetic engineering to develop genetically improved strains of crops and livestock animals.
genetic engineering
insertion of an alien gene into an organism to give it a beneficial genetic trait
genetically modified food (GMFs)
organisms whose genetic makeup has been modified by genetic engineering
rangelands
land that supplies forage or vegetation for grazing and browsing animals and is not intensively managed
overgrazing
destruction of vegetation when too many grazing animals feed too long and exceed the carrying capacity of a rangeland or pasture area
fisheries
concentrations of particular aquatic species suitable for commercial; harvesting in a give ocean area or inland body of water
aquaculture
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
trawling fishing
used to catch fish and shellfish that live on or near the ocean floor. It involves dragging a funnel shaped net held open at the neck along the ocean bottom and weighed down with chains or metal plates
bycatch
most of the fish and other aquatic species
pures-seien fishing
involves catching surface-dwelling species such as tuna, mackerel, anchovies, and herring, which tend to feed in schools near the surface or in shallow areas
longlining
involves putting out lines up to 140 kilometers (80miles) long, hung with thousands of baited hooks
drift-net fishing
fish are caught by huge drifting nets that can hang as much as 15 meters (50 ft) below the surface and be up to 64 kilometers (40 miles) long.
- leads to overfishing and may trap/kill large quantities of unwanted fish and marine mammals.
overfishing
taking of so many fish that too little breeding stock is left to maintain numbers
fish farming
involves cultivating fish in a controlled environment and harvesting them when they reach the desired size
fish ranching
involves holding anadromous species such as salmon that live part of their lives in fresh water and part in salt water in captivity for the the first few years of their lives, usually in fenced-in areas or floating cages in coastal lagoons and estuaries
sustainable (low-input agriculture, organic farming, agroecology)
method of food production that uses technology based on ecological knowledge to increase yields, control pests, and build soil fertility
relies more on perennial crops
