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96 Cards in this Set
- Front
- Back
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To survive and maintain good health, all forms of life must have enough...
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food, clean air, clean water, and shelter to meet their basic needs.
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An environmentally sustainable society satisfies the basic needs of its people without depleting or degrading its...
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natural resources
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Living sustainable means living off the natural income replenished by...
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soils, plants, air, and water
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Ecosystem services are the processes by which the environment produces resources such as...
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clean air, water, timber, and/or fish fertile soil.
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Ecosystems provide services that moderate…
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weather extremes.
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Ecosystems provide services that disperse…
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seeds and pollinate crops and natural vegetation
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Ecosystems provide services that protect...
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people from UV rays
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Ecosystems provide services that cycle and move...
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nutrients
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Ecosystems provide services that detoxify and decompose...
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wastes.
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Ecosystems provide services that control agricultural...
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pests.
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Ecosystems provide services that contribute to climate...
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stability.
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Ecosystems provide services that purify...
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air and water.
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Ecosystems provide services that generate and preserve...
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soils.
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Material Resources are Non-renewable and renewable resources. (T/F?)
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true
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Fossil fuels are examples of ... resources.
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finite
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A renewable resource can be replenished through natural processes as long as it is not...
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used up faster than it's replaced.
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Renewable resources are ... resources that pass through plants, economies, and other systems.
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flow
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Earth has perhaps ... plant species with parts that people can eat.
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30,000
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Only .. plant and ... terrestrial animal species supply 90% of our food.
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15 plant and 8 terrestrial
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Just three grain crops- ...-provide more than half the calories people consume.
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wheat, rice, and corn
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These three grains, and most other food crops, are...
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annuals.
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Two-thirds of the world's people survive primarily on...
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wheat, rice, and corn because they are to poor to eat meat.
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There are two major types of agricultural systems:
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industrialized and traditional.
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Industrialized agriculture, or high-input agriculture, uses large amounts of...
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fossil fuel energy.
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Industrialized agriculture is practiced on about ... of all cropland,
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25%
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Plantation agriculture is a form of ... practiced primarily in
tropical developing countries. |
industrialized agriculture
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Plantation agriculture involves growing...
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cash crops.
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An increasing amount of livestock production in developed countries is ...
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industrialized.
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Most pigs and chickens in developed countries spend their entire lives in ...
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densely populated pens and cages.
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41% of all freshwater used by humans in the United States was used for ...
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agriculture.
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Agriculture accounted for more than ... of US “consumptive use” of water.
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80%
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Industrial Agriculture and chemical fertilizer’s over-enrichment of nutrients (esp. NO3-) in water causes...
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algal blooms.
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Algal blooms increase water column...
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turbidity (killing sea grasses)
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In water, decaying organic matter leads to low oxygen, suffocating...
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marine animals.
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Industrialized agriculture and soil degradation leads to the loss of ... acres/year.
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12–17 million
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Erosion, desertification, salinization, water-logging, are common problems caused by...
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soil degradation
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Since the 1930's over ... biocides have been developed and used.
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500,000
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2700 known cases of resistance by ... species to >300 pesticides
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540
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Traditional agriculture consists of two main types:
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traditional subsistence agriculture & traditional intensive agriculture
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Traditional subsistence agriculture typically uses mostly ... labor.
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human
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Numerous forms of shifting cultivation in tropical forests and nomadic livestock herding are examples of...
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traditional subsistence agriculture.
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In traditional intensive agriculture, farmers increase their inputs of ... and ...labor
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human and draft
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... ... agriculture can produce enough food to feed a family's food needs and to sell for income.
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Traditional intensive agriculture
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Traditional farmers in developing countries today grow about ... of the world's food on about ... of its cultivated land.
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20%, 75%
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Many traditional farmers simultaneously grow several crops on the same...
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plot.
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growing several crops on the same plot, is a practice known as...
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interplanting.
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...reduces the chance of losing most or all of the year's food supply to pests, bad weather, and other misfortunes.
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Crop diversity
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Polyvarietal cultivation, in which a plot is planted with ... of the same crop.
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several varieties
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Intercropping, in which two or more ... crops are grown at the same time on a plot.
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different
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Agroforestry, or alley cropping, in which ... and ... are planted together.
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crops and trees
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Polyculture, a complex form of intercropping in which many different plants ... at various times are planted together.
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maturing
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Crop rotation can prevent...
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soil degradation.
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Contour farming -
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planting along contour lines of slopes
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Terracing -
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cutting stair steps or terraces
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The only method to farm on steep hillsides without causing massive erosion is...
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terracing.
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Shelterbelts rows -
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fast-growing trees around crop plantings provide windbreaks, reducing wind erosion
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Conservation tillage -
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reduced or no tillage
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Conservation tillage reduces erosion by...
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90%
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Forests provide numerous ecological...
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services.
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For example, 50-80% of the moisture in the air above tropical forests comes from...
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trees via transpiration and evaporation.
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If large areas of are cleared, average annual precipitation...
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drops and the region's climate gets hotter and drier.
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The world's forests provide habitats for ... of all terrestrial species
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50-90%
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Trees harvested from forests are worth more than ... per year.
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$400 billion
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Economic uses of forests include:
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Fuelwood, pulp for paper, lumber, medicines, mining, livestock grazing, and recreation.
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There are ... general types of forests.
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three
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Old-growth forests are ...forests or ... forests.
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uncut or regenerated
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snags -
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dead trees
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Stands of trees resulting from secondary ecological succession.
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Second-growth forests
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Some old-growth and second-growth forests have been cleared and converted to ...
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tree farms or plantations.
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Tree farms or plantations contain trees of ...
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one species.
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Tree farms or plantations contain trees that are harvested by clear-cutting as soon as they become ...
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commercially valuable.
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Forests are ... resources.
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renewable
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Deforestation decreases the overall... of an area.
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net primary productivity
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Deforestation reduces the stock of...
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nutrients.
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Deforestation diminishes...
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biodiversity.
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Deforestation makes the soil more prone to...
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erosion and drying.
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Deforestation increases the rate of...
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runoff of water.
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Deforestation reduces the uptake of ...
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CO2.
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Deforestation contributes to...
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global warming.
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There are two basic forest management systems:
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even-aged and un-even-aged.
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Even-aged management (industrial forestry), trees in a given stand are maintained at...
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about the same age and size.
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Intensive even-aged management of forests has shown that in a forest in which almost all the trees are repeatedly cut and removed, ...
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the soil is depleted of nutrients.
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In uneven-aged management, a variety of tree species in a given stand are maintained at...
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many ages, and sizes to foster natural regeneration.
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Boom-bust cycles:
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Extensive clear-cutting can greatly increase short- term profits
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Before large amounts of timber can be harvested, ...
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roads must be built for access.
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Selective cutting reduces...
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crowding.
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Selective cutting encourages ...
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growth of younger trees.
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Selective cutting maintains an uneven-aged stand of trees of ...
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different species.
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Selective cutting allows natural regeneration from the...
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surrounding trees.
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Selective cutting allows a forest to be used for ...
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multiple purposes.
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Shelterwood cutting removes all... in two or three cuttings over ten years.
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mature trees
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Shelterwood cutting allows natural seeding from the ...
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best seed trees.
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Shelterwood cutting keeps seedlings from being ...
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crowded out.
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Shelterwood cutting helps reduce...
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soil erosion.
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... is individuals or biomass removed or harvested from a population per unit time.
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Yield
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.. is when the yield per unit time is equal to the production per unit time of an exploited population.
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Sustained yield
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