enviromental chapter 16 test

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fish and shellfish supply what percent of global food supply: 7%
industrial fishing fleets use 6 things to dominate the commercial industry: 1. sateillite positioning equipment.
2. sonar
3. huge nets.
4. spotter planes
5. factory ships
6.
what percent of annual catches comes from industrialized fishing metholds: 55%
Other than commercial fishing methods, annual catches come from what?: aquaculture--33% of annual catches
what is aquaculture: raising of marine and freshwater fish in ponds and underwater cages
inland fresh water fishing accounts for what percent of annual catches?: 12%
The decline of the commerical fish catch has been falling since 1992 because of what 4 reasons: 1. overfishing
2. habitat loss
3. population
4. population growth
sustainable yield: the size of the annual catch that could be harvested indefinitely without a decline in the population of a species.
Why should sustainable yield be established?: Each species should have sustainable yields established to avoid depleting the stock
Why is sustainable yeild difficult to determine?: 1. hard to estimate mobile aquatic populations
2. shift from year to year due to changes in climate, pollution
3. may severly reduce the population of other species that rely on it for food
Bycatch is?: the nontarget fish that are caught in nets and then thrown back into the sea
What is one agrument for continuing gov't subsidies of commercial fishing industry?: Phasing out subsidies would cause a loss in jobs for some fishers and fish processors in coastal communities
What is one arguement against continuing gov't subsidies of the commercial fishing industry?: Costs too much money. Government subsides such as fuel tax exemptions, price controls, low interest loans and grants for fishing cost $50 billions a year.
Two basic types of aquaculture?: fish farming and fish ranching
Fish farming: Cultivating fish in a controlled enviroment and harvesting them when the reach the desired size.
Fish ranching: holding anadromous species such as salmon in captivity for 1st few years of lives, usually in a lagoon
What two factors give aquaculture a large cost advantage over raiising livestock like cattle?: 1. Fish take 2kg of grain to gain 1kg of live weight, cows take 7 kgs of grain to gain 1 kg of live weight.
2. fish takes less water per kg of fish, cow takes 1000 kg of water to produce 1 kg of wieght
Why wont increasing both the wild catch and aquaculture not increase the world food supply significantly?: Fish and shellfish supply only about 1% of the calories and 7% of the protein in the human diet
Whyis rangeland unsuitable for growing crops: Too dry, to steeply sloped or too infertile to grow crops
Whats the difference between pastures and rangeland?: Pastures are managed grasslands or enclosed meadows usually planted with domesticated grasses or other foliage
meat and meat products are a good source of: protein
What are 4 problems generally associated with meat production throughout the world?: 1.Nitrates from animal wastes can contaminate drinking water
2.increases pressure on the worlds grain supply due to livestock and fish raised for food consumed 37% of worlds grain
3. it can endanger wildlife species
4.use more than half of the water withdrawn worldwide from rivers and aquifiers each year
occurs when too many animals graze for too long and exceed the carrying capactiry of a grass land area: Overgrazing
what is the primary goal of sustainable yield?: to maximize livestock prodcutivity with out overgrazing or undergrazing rangeland vegetation
What are riparian zones and why are they ecologically important?: they are thin strips of lush vegetation along steams. they are ecologically important areas because they help keep streams from drying out during droughts by storing and relaeasing water slowly from spring runoff and summer storms
What are fisheries?: concentrations of particular aquatic species suitable for commercial harvesting in a given ocean area or inland body of water
Is it likely that reudcing livestock production would result in more land being available for growing crops?: No, this would decrease the environmental impact of livestock production but it would not free up much land or grain to feed more of the worlds hungry people.
Animal products provide: 15% of the energy and 30% of the protein in the human diet
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. See fish farming, fish ranching
annual: Plant that grows, sets seed, and dies in one growing season. Compare perennial.
alley cropping: Planting of crops in strips with rows of trees or shrubs on each side
agroforestry: Planting trees and crops together
arable land: Land that can be cultivated to grow crops
biological pest control: Control of pest populations by natural predators, parasites, or disease-causing bacteria and viruses (pathogens
calorie: Unit of energy; amount of energy needed to raise the temperature of 1 gram of water 1!C (unit on Celsius temperature scale). See also kilocalorie
commercial extinction: Depletion of the population of a wild species used as a resource to a level at which it is no longer profitable to harvest the species.
domesticated species: Wild species tamed or genetically altered by crossbreeding for use by humans for food (cattle, sheep, and food crops), pets (dogs and cats), or enjoyment (animals in zoos and plants in gardens). Compare wild species
drift-net fishing: Catching fish in huge nets that drift in the water
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
feedlot: Confined outdoor or indoor space used to raise hundreds to thousands of domesticated livestock. Compare rangeland
fishery: Concentrations of particular aquatic species suitable for commercial harvesting in a given ocean area or inland body of water.
fungicide: Chemical that kills fungi.
gene splicing: genetic engineeringInsertion of an alien gene into an organism to give it a beneficial genetic trait. Compare artificial selection, natural selection.
genetically modified organism (GMO): Organism whose genetic makeup has been modified by genetic engineering.
green revolution: 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.
herbicide: Chemical that kills a plant or inhibits its growth.
high-input agriculture: industrialized agricultureUsing 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.
insecticide: Chemical that kills insects.
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 size that causes economically unacceptable loss of a crop or livestock animal.
intercropping: 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. Compare monoculture, polyculture, polyvarietal cultivation.
interplanting: Simultaneously growing a variety of crops on the same plot. See agroforestry, intercropping, polyculture, polyvarietal cultivation.
kilocalorie (kcal): Unit of energy equal to 1,000 calories. See calorie.
low-input agriculture: sustainable agriculture.
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. Compare overnutrition, undernutrition.
monoculture: Cultivation of a single crop, usually on a large area of land. Compare polyculture, polyvarietal cultivation.
net primary productivity (NPP): Rate at which all the plants in an ecosystem produce net useful chemical energy; equal to the difference between the rate at which the plants in an ecosystem produce useful chemical energy (gross primary productivity) and the rate at which they use some of that energy through cellular respiration. Compare gross primary productivity.
organic farming: Producing crops and livestock naturally by using organic fertilizer (manure, legumes, compost) and natural pest control (bugs that eat harmful bugs, plants that repel bugs, and environmental controls such as crop rotation) instead of using commercial inorganic fertilizers and synthetic pesticides and herbicides. See sustainable agriculture.
overfishing: Harvesting so many fish of a species, especially immature fish, that there is not enough breeding stock left to replenish the species, such that it is not profitable to harvest them.
overgrazing: Destruction of vegetation when too many grazing animals feed too long and exceed the carrying capacity of a rangeland or pasture area.
overnutrition: Diet so high in calories, saturated (animal) fats, salt, sugar, 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. Compare malnutrition, undernutrition.
pasture: Managed grassland or enclosed meadow that usually is planted with domesticated grasses or other forage to be grazed by livestock. Compare feedlot, rangeland.
perennial: Plant that can live for more than 2 years. Compare annual.
pest: Unwanted organism that directly or indirectly interferes with human activities.
pesticide: Any chemical designed to kill or inhibit the growth of an organism that people consider undesirable. See fungicide, herbicide, insecticide.
plantation agriculture: Growing specialized crops such as bananas, coffee, and cacao in tropical developing countries, primarily for sale to developed countries.
polyculture: Complex form of intercropping in which a large number of different plants maturing at different times are planted together. See also intercropping. Compare monoculture, polyvarietal cultivation.
polyvarietal cultivation: Planting a plot of land with several varieties of the same crop. Compare intercropping, monoculture, polyculture.
radioactivity: Nuclear change in which unstable nuclei of atoms spontaneously shoot out 'chunks' of mass, energy, or both at a fixed rate. The three principal types of radioactivity are gamma rays and fast-moving alpha particles and beta particles.
response: The amount of health damage caused by exposure to a certain dose of a harmful substance or form of radiation. See dose, dose-response curve, median lethal dose.
surface runoff: Water flowing off the land into bodies of surface water. See reliable runoff.
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.
toxic chemical: Chemical that is fatal to humans in low doses or fatal to more than 50% of test animals at stated concentrations. Most are neurotoxins, which attack nerve cells. See carcinogen, hazardous chemical, mutagen, teratogen.
toxicity: Measure of how harmful a substance is.
tree plantation: Site planted with one or only a few tree species in an even-aged stand. When the stand matures it is usually harvested by clear-cutting and then replanted. These farms normally are used to grow rapidly growing tree species for fuelwood, timber, or pulpwood. See even-aged management. Compare old-growth forest, second-growth forest, uneven-aged management.
trophic level: All organisms that are the same number of energy transfers away from the original source of energy (for example, sunlight) that enters an ecosystem. For example, all producers belong to the first trophic level, and all herbivores belong to the second trophic level in a food chain or a food web.

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