Flashcards in Chapter 14 Deck (52):
planting a mixture of different crops in the same area. this involves planting a mix of perennial grasses, legumes, sunflowers, grain crops, and plants that provide natural insecticides in the same field.
plant that can live for more than 2 years.
plant that grows, sets seeds, and dies in one growing season.
industrialized agriculture (high-input agriculture)
uses large amounts of fossil fuel energy, water, commercial fertilizers, and pesticides to produce single crops (monocultures) or livestock animals for sale.
is a form of industrialized agriculture used primarily in tropical developing countries. Involves growing cash crops.
traditional subsistence agriculture
typically uses mostly human labor and draft animals to produce only enough crops or livestock for a farm family's survival.
Tradition intensive agriculture
farmers increase their inputs of human and draft labor, fertilizer, and water to get a higher yield per area of cultivated land.
popular term for introduction of scientifically bred or selected varieties of grain (rice, wheat, maize) that, with high enough inputs of fertilizer and water, can greatly increase crop yields.
second green revolution
involves introducing fast-growing dwarf varieties of rice and wheat into several developing countries in tropical and subtropical climates.
many traditional farmers simultaneously grow several crops on the same plot.
involves planting a plot with several varieties of the same crop.
growing two or more different crops at the same time on a plot.
agroforestry (alley cropping)
crops and trees are grown together
many different plants maturing at various times are planted together.
occurs when natural or human-induced processes decrease the future ability of land to support crops, livestock, or wild species.
the movement of soil components, especially surface litter and topsoil from one place to another.
the productive potential of arid or semiarid land falls by 10% or more because of a combination of natural climate change that causes prolonged drought and human activities that reduce or degrade topsoil.
repeated annual applications of irrigation water lead to the gradual accumulation of salts in the upper soil layers.
saturation of soil with irrigation water or excessive precipitation so that the water table rises close to the surface.
involves using ways to reduce soil erosion and restore soil fertility.
farmers plow the land and then break up and smooth the soil to make a planting surface.
farmers use it to disturb the soil as little as possible while planting crops.
can reduce soil erosion on steep slopes by converting the land into a series of broad, nearly level terraces that run across the land contour.
involves plowing and planting crops in rows across the slope of the land rather than up and down
involves planting alternating strips of a row crop and another crop that completely covers the soil.
the planting of crops such as alfalfa, clover, or rye immediately after harvest to help protect and hold the soil.
farms establish to reduce wind erosion, help retain soil moisture, supply wood for fuel, and provide habitats for birds, pest-eating and pollinating insects, and other animals.
organic material such as animal manure, green manure, and compost, applied to cropland as a source of plant nutrients.
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.
the dung and urine of cattle, horses, poultry, and other farm animals.
consists of freshly cut or growing green vegetation plowed into the soil to increase the organic matter and humus available to the next crop.
produced when micro-organisms in soil break down organic matter such as leaves, food wastes, paper, and wood in the presence of oxygen.
planting a field, or an area of a field, with different crops from year to year to reduce soil nutrient depletion.
people who cannot grow or buy enough food to meet their basic energy needs suffer.
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.
occurs when food energy intake exceeds energy use and causes excess body fat.
third green revolution
or gene revolution, by using genetic engineering to develop genetically improved strains of crops and livestock animals.
insertion of an alien gene into an organism to give it a beneficial genetic trait.
genetically modified food
is seen by its producers and investors as a potentially sustainable way to solve world food problems but critics consider it potential dangerous "Frankenfood"
are grasslands in temperate and tropical climates that supply forage and vegetation for grazing and browsing animals.
occurs when too many animals graze too long and exceed the carrying capacity of a grassland area.
concentrations of particular aquatic species suitable for commercial harvesting in a given ocean area or inland body of water.
to raise marine and freshwater fish like livestock animals in feedlots in ponds and underwater cages and from inland freshwater fishing from lakes, rivers, reservoirs, and ponds.
his used to catch fish and shellfish that live on or near the ocean floor.
most of the fish and other aquatic species are thrown back into the ocean dead or dying.
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.
involves putting out lines up to 130 kilometers (80 miles) long, hung with thousands of baited hooks.
fish are caught by huge drifting nets that can hang as much as 15 meters (50 feet) below the surface and be up to 64 kilometers (40 miles) long.
is the taking of so many fish that too little breeding stock is left to maintain numbers
involves cultivating fish in a controlled environment and harvesting them when they reach the desired size.
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 first few years of their lives, usually in fenced-in areas or floating cages in coastal lagoons and estuaries.