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When fish populations are temporarily reduced due to overfishing, they are said to be _____.
tragedy of the commons
The depletion of the world's marine fish stocks due to overfishing is a classic example of _____.
International Whaling Commission
intergovernmental organization that sets quotas for hunting certain whale species
optimum sustainable yield
_____ is the most beneficial to fish populations when estimating marine fish populations.
US Army Corps of Engineers
The _____ is responsible for undoing the development of the Everglades that the same agency has done since the 1940s.
_____ was introduced into the Great Lakes and has now spread through most of the major river systems in central and eastern U.S.
national wild and scenic rivers act
Under _____ protection can be offered to rivers and river segments with cultural and historic value, wildlife and scenic value, and recreational value.
Value of an organism, species, ecosystem, or the earth's biodiversity based on its existence, regardless of whether it has any usefulness to us.
The irrevocable elimination of species; can be a normal process of the natural world as species out-compete and kill off others or as environmental conditions change
habitat conservation plan
Agreements under which property owners are allowed to harvest resources or develop land as long as habitat is conserved or replaced in ways that benefit resident endangered or threatened species in the long run. Some incidental "taking" or loss of endangered species is generally allowed in such plans
Organisms that thrive in new territory where they are free of predators, diseases, or resource limitations that may have controlled their population in their native habitat
While still abundant in parts of its territorial range, this species has declined significantly in total numbers and may be on the verge of extinction in certain regions or localities
Naturally rare organisms or species whose numbers have been reduced by human activities that they are susceptible to actions that could push them into threatened or endangered status
a nuclear reaction in which an atomic nucleus, especially a heavy nucleus such as an isotope of uranium, splits into fragments, usually two fragments of com¬parable mass, releasing from 100 million to several hundred million electron volts of energy.
a hydrocarbon deposit, such as petroleum, coal, or natural gas, derived from living matter of a previous geologic time and used for fuel.
First Law of Thermodynamics
says that energy can neither be created nor destroyed; it can only be transferred and transformed.
the rocks and Earth that is removed when mining for a commercially valuable mineral resource.
devices containing alkaline substances that precipitate out much of the sulfur dioxide from industrial plants.
Second Law of Thermodynamics
when energy is changed from one form to another, some useful energy is always degraded into lower quality energy (usually heat)
involves the removal of the Earth's surface all the way down to the level of the mineral seam.
involves the sinking of shafts to reach underground deposoits. In this type of mining, networks of tunnels are dug or blasted and humans enter these tunnels in order to manually retrieve the coal.
removing shallow deposits such as nonfuel mineral and rock resources and 60% of U.S. coal
used for extracting mineral deposits that lie close to the earth's surface in large horizontal beds
Cyanide heap extraction
involves spraying toxic cyanide salts on heaps of crushed ore, where it reacts with the material and separates the gold from the ore
Surface Mining Control and Reclamation Act
requires mining companies to restore most surface-mined land by grading and replanting it
the amount of high-quality energy that is available to be used from a resource after subtracting the energy needed to make it usable
a thick liquid hydrocarbon that is extracted from underground deposits and separated into a wide variety of products
made of long chains of carbon atoms bonded together and also bonded to hydrogen, as well as smaller amounts of sulfur, oxygen, and nitrogen
passes when the pressure starts to decline and more and more energy is expended to get oil to the surface (Generally only 35-50% of oil is retrieved from any particular well)
brown coal; coal with a low heat content; low sulfur content; limited supplies in most areas
soft coal; Coal that is extensively used as a fuel because of its high heat content and large supplies; normally has a high sulfur content
hard coal; highly desirable fuel because of its high heat content and low sulfur content; supplies are limited in most areas
the process behind the concept of "clean coal," and is designed to remove carbon dioxide from the emissions produced by burning coal and turn coal into liquid gas fuel
A broad, regional type of ecosystem characterized by distinctive climate and soil conditions and a distinctive kind of biological community adapted to those conditions.
An area of waterlogged soil that tends to be peaty; fed mainly by precipitation; low productivity; some are acidic.
A broad band of mixed coniferous and deciduous trees that stretches across northern North America (and also Europe and Asia); its northernmost edge, the taiga, intergrades with the arctic tundra,
High mountain forests where temperatures are uniformally cool and fog or mist keeps vegetation wet all the time.
Prominent oceanic features composed of hard, limy skeletons produced by coral animals; usually formed along edges of shallow, submerged ocean banks or along shelves in warm, shallow, tropical seas.
A type of biome characterized by low moisture levels and infrequent and unpredictable precipitation. Daily and seasonal temperatures fluctuate widely.
Wetland without trees; in North America, this type of land is characterized by cattails and rushes.
The northernmost edge of the boreal forest, including species-poor woodland and peat deposits; intergrading with the arctic tundra.
The cool, dense rainy forest of the northern Pacific coast; enshrouded in fog much of the time; dominated by large conifers.
Forests in which rainfall is abundant- more than 00 cm (80 in.) per year- and temperatures are warm to hot year-round.
Treeless arctic or alpine biome characterized by cold, harsh winters, a short growing season, and potential for frost any month of the year; vegetation includes low-growing perennial plants, mosses, and lichens.
Ecosystems of several types in which rooted vegetation is surrounded by standing water during part of the year.
The maximum reproductive rate of an organism when given unlimited resources and ideal environmental conditions.
the maximum number of individuals of any species that can be supported by a particular ecosystem on a long term basis
a population founded when just a few members of a species survive a catastrophic event or create a new habitat geographically isolated from other members of the same species
all the limiting factors that tend to reduce population growth rates, set the maximum allowable population growth rates and set the maximum allowable population size or carrying capacity of an ecosystem
growth at a constant rate of increase per unit of time; can be expressed as a constant fraction or exponent
measurement of actual number of offspring produced through sexual reproduction: usually described in terms of number of offspring of females, since paternity can be difficult to determine
the effect on a population founded when just a few members of a species survive a catastrophic event or when they create a new habitat geographically isolated from other members of the same species
the study of rates of colonization and extinction of species on islands or other isolated areas based on size, shape, and distance from other inhabited regions
the average age that a newborn infant can expect to attain in a particular time and place
growth rates regulated by internal and external factors that establish an equilibrium with environmental resources
a sudden population decline caused by predation, waste accumulation, or resource depletion
growth of a population at exponential rates to a size that exceeds environmental carrying capacity; usually followed by a population crash
the percentage of a population reaching a given age or the proportion of the maximum life span of the species reached by any individual
Any genetically controlled structural, physiological, or behavioral characteristic that helps an organism survive and reproduce under a given set of environmental conditions. It usually results from a beneficial mutation.
Process in which numerous new species evolve to fill vacant and new ecological niches in changed environments, usually after a mass extinction. Typically, this takes millions of years.
Process by which humans select one or more desirable genetic traits in the population of a plant or animal species and then use selective breeding to produce populations containing many individuals with the desired traits. Compare genetic engineering, natural selection.
Normal extinction of various species as a result of changes in local environmental conditions. Compare mass depletion, mass extinction.
Change in the genetic makeup of a population of a species in successive generations. If continued long enough, it can lead to the formation of a new species. Note that populations not individuals evolve. See also adaptation, differential reproduction, natural selection, theory of evolution.
Use of genetically engineered animals to act as biofactories for producing drugs, vaccines, antibodies, hormones, industrial chemicals such as plastics and detergents, and human body organs.
Formation of the earth and its early crust and atmosphere, evolution of the biological molecules necessary for life, and evolution of systems of chemical reactions needed to produce the first living cells. These processes are believed to have occurred about 1 billion years before biological evolution. Compare biological evolution.
Evolution in which two or more species interact and exert selective pressures on each other that can lead each species to undergo various adaptations. See evolution, natural selection.
Phenomenon in which individuals with adaptive genetic traits produce more living offspring than do individuals without such traits. See natural selection.
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.
Total way of life or role of a species in an ecosystem. It includes all physical, chemical, and biological conditions a species needs to live and reproduce in an ecosystem. See fundamental niche, realized niche.
Species that is found in only one area. Such species are especially vulnerable to extinction.
Complete disappearance of a species from the earth. This happens when a species cannot adapt and successfully reproduce under new environmental conditions or when it evolves into one or more new species. Compare speciation. See also endangered species, mass depletion, mass extinction, threatened species.
Skeletons, bones, shells, body parts, leaves, seeds, or impressions of such items that provide recognizable evidence of organisms that lived long ago.
The full potential range of the physical, chemical, and biological factors a species can use if there is no competition from other species. See ecological niche. Compare realized niche.
The sum total of all genes found in the individuals of the population of a particular species.
Species with a broad ecological niche. They can live in many different places, eat a variety of foods, and tolerate a wide range of environmental conditions. Examples are flies, cockroaches, mice, rats, and human beings. Compare specialist species.
Changes in the genetic makeup of organisms of a species that allow the species to reproduce and gain a competitive advantage under changed environmental conditions. See differential reproduction, evolution, mutation, natural selection.
Insertion of an alien gene into an organism to give it a beneficial genetic trait. Compare artificial selection, natural selection.
Long-term, large-scale evolutionary changes among groups of species. Compare microevolution.
Widespread, often global period during which extinction rates are higher than normal but not high enough to classify as a mass extinction. Compare background extinction, mass extinction.
A catastrophic, widespread, often global event in which major groups of species are wiped out over a short time compared with normal (background) extinctions. Compare background extinction, mass depletion.
Random change in DNA molecules making up genes that can alter anatomy, physiology, or behavior in offspring. See mutagen.
Process by which a particular beneficial gene (or set of genes) is reproduced in succeeding generations more than other genes. The result of natural selection is a population that contains a greater proportion of organisms better adapted to certain environmental conditions. See adaptation, biological evolution, differential reproduction, mutation.
Parts of the fundamental niche of a species that are actually used by that species. See ecological niche, fundamental niche.
Long-term geographic separation of members of a particular sexually reproducing species.
Species with a narrow ecological niche. They may be able to live in only one type of habitat, tolerate only a narrow range of climatic and other environmental conditions, or use only one type or a few types of food. Compare generalist species.
Formation of two species from one species because of divergent natural selection in response to changes in environmental conditions; usually takes thousands of years. Compare extinction.
theory of evolution
Widely accepted scientific idea that all life forms developed from earlier life forms.
any heritable trait that enables an organism to survive through natural selections and reproduce better under prevailing environmental conditions
abiotic factors that limit an organisms ability to survive in an area according to their range of tolerance and genetic makeup
Pollution-putting nondegradeable materials into the environment, chemicals into the waters, burning fossil fuels, leads to climate change
biological and chemical processes such as energy flow and mater recycling needed for the SURVIVAL of ORGANISMS (species, communities, and ecosystems)
nutrients cycling in a continuous flow in various forms from the environment to organisms and back to the environment
evaporation + transpiration-->condensation-->precipitation->infiltration+peroculation-->ground water movement+surface runoff-->evaporation + transpiration
nitrogen fixation-->ammonification-->nitrification + nitrifying bacteria-->assimilation-->nitrification-->nitrifying bacteria-->denitrifying bacteria-->nitrogen fixation
mixture of decomposed organic matter, organic matter, inorganic minerals (rocks, sand, clay, insects), water and air
fertile soil. partially decomposed bodies of dead plants and animals that the topsoil (a horizon) is a porous mixture of.
Any method used to reduce births, including celibacy, delayed marriage, contraception; devices or medication that prevent implantation of fertilized zygotes, and induced abortions
The process by which a country moves from relatively high birth and death rates to relatively low birth and death rates
Controlling reproduction; planning the timing of birth and having as many babies as are wanted and can be supported
Total growth rate
The net rate of population growth resulting from births, deaths, immigration, and emigration
Land along a coastline, extending inland from an estuary, that is covered with salt water all or part of the year. Examples are marshes, bays, lagoons, tidal flats, and mangrove swamps.
Warm, nutrient-rich, shallow part of the ocean that extends from the high-tide mark on land to the edge of a shelflike extension of continental land masses known as the continental shelf.
Single-celled, prokaryotic, microscopic organisms. Before being reclassified as monera, they were called blue-green algae.
Partially enclosed coastal area at the mouth of a river where its fresh water, carrying fertile silt and runoff from the land, mixes with salty seawater.
Upper layer of a body of water through which sunlight can penetrate and support photosynthesis.
Lake with a large or excessive supply of plant nutrients, mostly nitrates and phosphates.
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.
freshwater life zones
Aquatic systems where water with a dissolved salt concentration of less than 1% by volume accumulates on or flows through the surfaces of terrestrial biomes. Examples are standing (lentic) bodies of fresh water such as lakes, ponds, and inland wetlands and flowing (lotic) systems such as streams and rivers.
Land away from the coast, such as a swamp, marsh, or bog, that is covered all or part of the time with fresh water.
Large natural body of standing fresh water formed when water from precipitation, land runoff, or groundwater flow fills a depression in the earth created by glaciation, earth movement, volcanic activity, or a giant meteorite.
Swamps found on the coastlines in warm tropical climates. They are dominated by mangrove trees, any of about 55 species of trees and shrubs that can live partly submerged in the salty environment of coastal swamps.
Small plant organisms (phytoplankton) and animal organisms (zooplankton) that float in aquatic ecosystems.
Fresh water from precipitation and melting ice that flows on the earth's surface into nearby streams, lakes, wetlands, and reservoirs.
Precipitation that does not infiltrate the ground or return to the atmosphere by evaporation or transpiration.
Zone of gradual temperature decrease between warm surface water and colder deep water in a lake, reservoir, or ocean.
Process in which water is absorbed by the root systems of plants, moves up through the plants, passes through pores (stomata) in their leaves or other parts, and evaporates into the atmosphere as water vapor.
Land area that delivers water, sediment, and dissolved substances via small streams to a major stream (river).
an uncut or regenerated primary forest that has not been seriously disturbed by human activities or natural disasters for 200 years or more
managed tracts with uniformly aged trees of one or two genetically uniform species that usually are harvested by clear-cutting as soon as they become commercially valuable
clear-cutting a strip of trees along the contour of land within a corridor narrow enough to allow natural regeneration
good; usually burn only undergrowth and lead litter on forest floor; spare most mature trees; help prevent worse fires, allow vegetation to flourish
bad; extremely hot, leaps from treetop to treetop, destroy vegetation, kill wildlife, damage human structures
the temporary or permanent removal of large expanses of forest for agriculture, settlements, or other uses
provide soil formation, erosion control, nutrient cycling, storage of atmospheric Co2 in biomass, and maintenance of biodiversity
unfenced grasslands in temperate and tropical climates that supply vegetation for grazing or browsing animals
managed grasslands or enclosed meadows usually planted with domesticated grasses or other forage
occurs when too many animals graze for too long and exceed the carrying capacity of a rangeland area; reduces grass cover, exposes the soil to erosion by water
cattle are confined by portable fencing to one area for a short time and then moved to a new location
buffer zone concept
protecting the inner core of a preserve by establishing 2 buffer zones in which local people can extract resources sustainably without harming the inner core
protected areas between isolated reserves, help support more species and allow migration for vertebrates that need large ranges
a federal regulation that put undeveloped areas of national forests off-limits to road building and logging while they were evaluated for wilderness protection
returning a particular degraded habitat to a condition as similar as possible to its natural state
turning a degraded ecosystem into a functional ecosystem without trying to restore it to its original state
working together, compromising, finding ways to share land; inventing, establishing and maintaining new habitats to conserve species diversity in places where people live, work, or play
when a parasite feeds on part of the host (usually by living on or inside of them). Promotes biodiversity and controls population by keeping one species from being too plentiful that they eliminate other species
the ability of one species to become most efficient in acquiring resources leading another species to 1)migrate and therefore change its feeding habits through natural selection or 2) population decline or 3) extinction in that area.
the biological change in communities over time due to changing environmental conditions
the establishment of various communities in places that contain soil or bottom sentiment, life was there prior
when the species of a community modifies/changes the environment by creating beneficial conditions for another species to move in
natural (earth quakes, plate tectonics, climate change) and human made environmental changes that leads ecosystems to readjust theirselves
sustainable environments have greater biodiversity. the ability of the earth's various systems to survive and adapt to changing environmental conditions.
when an ecosystem adapts/changes in order to survive changing environmental conditions
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