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TEACH Glossary

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acid rain
Airborne toxic contaminants, such as car emissions and the burning of other fossil fuels, enter the atmosphere and come back down to the land in the form of acid rain

1: a branch of philosophy dealing with the nature of beauty, art, and taste and with the creation and appreciation of beauty  2: a pleasing appearance or effect

a food fish of the herring family that is very abundant on the Atlantic coast; the alewife entered the Great Lakes through the Welland Canal in the 1940s and frequently die-off in large numbers because they are not well adapted to life in freshwater.
See also: Alewife, Alosa pseudoharengus

plants that have an enclosed seed. Examples: all flowering plants, including many hardwood trees, such as maples and oaks.

aquaculture (also known as aquiculture)
the cultivation of the natural produce of water (as fish or shellfish)

an expanse of water with many scattered islands; a group of islands

atmosphere, atmospheric science
the study of the air surrounding the earth, or the atmosphere

having the right or power of self-government; existing or capable of existing independently

ballast water
fresh or salt water (sometimes containing sediments) held in tanks and cargo holds of ships to increase stability and maneuverability during transit

large, flat-bottomed boat used on rivers and canals

barrier beach wetlands
created when a sand beach is created across a bay, resulting in an embayment connected to a lake by a channel, which protects the barrier beach from wave action. Bark Bay and Siskiwit Bay on Lake Superior and Oshawa Second Marsh on Lake Ontario are examples of barrier beach wetlands.

barometric pressure (also known as atmospheric pressure)
the pressure at any point in an atmosphere due solely to the weight of the atmospheric gases above the point concerned

the entire land area drained by a lake. Any pollution that occurs in a basin, even if it occurs far away from the lake itself, can eventually wind up in the lake. Also known as a watershed.

baymouth barriers
low ridges composed of beach sand where waves have eroded sections along the shore to form cliffs

beach dunes
dunes that develop on the low-lying shores of Lake Michigan, consisting mostly of sand

the solid rock underlying the surface materials (soils)

the bottom of a body of water and the organisms that live there

The net accumulation of a contaminant in an organism from all sources, including air, water and food. Toxic chemicals tend to bioaccumulate in the fatty tissues of fish, and these toxins increase in concentration as they are passed from the prey to the predator (called biomagnification).

biological diversity in an environment as indicated by numbers of different species of plants and animals

a branch of knowledge that deals with living organisms and vital processes

a disease or injury of plants resulting in withering, stopping of growth, and death of parts without rotting

abandoned, idled, or under-used industrial and commercial facilities where expansion, redevelopment, or reuse is complicated by real or perceived environmental contamination
See also: Great Lakes Regional Online Brownfields Information Network (ROBIN)

type of wetland ecosystem characterized by wet, spongy, poorly drained peaty soil

long pole

a favor given in answer to a request

front end of a boat or ship

containing some salt; brackish water: the area in a waterbody where freshwater and saltwater meet

literally means "between the capes"; U.S. Maritime Cabotage Laws include 31 separate enactments governing the transportation of cargo and passengers between any two points in the United States, its territories and possessions, and all dredging, towing, salvage and other marine operations and fishing in U.S. waters. See also: By the Capes: A Primer on U.S. Coastwise Laws

a watertight chamber used in construction work under water or as a foundation

a highly ornamented ceremonial pipe of the American Indians; illustration

cargo (or bulk cargo)
goods like wheat, coal or oil that must be shoveled, scooped, pumped or blown into a ship; any goods or merchandise transported in a ship, airplane or vehicle

any vessel for transporting materials or people

a narrow walkway connecting two points, usually suspended in the air

the processed, salted eggs of a large fish (such as sturgeon); a delicacy

the basic structural component of plant cell walls, making them rigid and "boxed" shaped

a machine that uses centrifugal force to separate substances of different densities, to remove moisture, or to simulate gravitational effects

the course, sometimes marked by buoys, that a ship follows in open water

a science that deals with the composition, structure, and properties of substances and with the transformations that they undergo

civil engineer
an engineer whose training or occupation is in the design and construction especially of public works (such as roads or harbors)

to completely cut down a forest, including the trees, plants, and grasses

solid substance left after gas and tar have been extracted from coal, used as fuel

combined sewer overflows (CSOs)
Sewer systems that combine both sewage and stormwater flow into one pipe are called combined sewer systems. Many cities found this system beneficial because, during a powerful rainstorm, water would not back up into people's basements, but would be taken directly to the outlet, usually a river or lake. Unfortunately, CSOs dump toxic pollutants, such as E. coli, into the water and create a public health threat.
See also: What are CSOs?

commercial fishing
the act of fishing with the intent to make a profit from selling the catch to consumers

an article of commerce especially when delivered for shipment

constitution (in relation to laws and policy)
a : the basic principles and laws of a nation, state, or social group that determine the powers and duties of the government and guarantee certain rights to the people in it b : a written instrument embodying the rules of a political or social organization

conventional pollutants
Otherwise nontoxic, conventional pollutants, such as dirt, can contaminate a water body by making the water unusable for drinking and swimming, and ultimately destroying fragile aquatic life

continuous moving belt to transport objects from one place to another

a class of arthropod animals having jointed feet and mandibles, two pairs of antennae, and segmented, chitin-encased bodies

crust of the earth
the outermost solid layer of the earth, mostly consisting of crystalline rock

repeating itself in some manner in space or time; following a cycle

DDT was a manufactured chemical mainly used as a pesticide on agricultural crops. DDT attacks the nervous system, and many animals, such as birds, died as a result of spraying the pesticide on fields and trees. Because of damage to wildlife and the potential harm to human health DDT was banned in 1972 in the United States, although the chemical still persists today in soil and water contamination and in the fatty tissues of fish, birds, and other animals.
See also: The Story of Silent Spring and Rachel Carson.

someone or something used to lure or lead another into a trap; example: an artificial bird used to attract live birds within shot-range when hunting

oil-burning engine in which ignition is produced by the heat of compressed air

an artificial watercourse; a bank usually of earth constructed to control or confine water, such as a levee

Dioxins are often formed during the chlorination process at paper mills and waste and drinking water treatment plants; they are also released into the air by municipal solid waste and industrial incinerators. Dioxins accumulate in fatty tissues of animals, and have been linked to skin disease, liver damage and cancer in humans.

located near or on the back of an animal or one of its parts

toward the Atlantic Ocean

draft (or draught)
depth of water needed to float a ship

to deepen a waterway with a dredging machine
See also: Great Lakes Dredging Team

a hill or ridge of sand piled up by the wind
See also: Dunes in the Great Lakes Region

E. coli (Escherichia coli)
E. coli is a bacteria naturally found within the intestinal tracts of humans and other animals, and is necessary for proper development and health. Certain strains of E. coli, however, can be extremely harmful, even fatal, if ingested. E. coli is found in human and animal wastes, and can infect drinking water if not properly treated through a wastewater treatment plant.

related to the interrelationships which exist between living organisms and their environment

the relationship of air, land, water and all living beings; a community of organisms and its environment

an animal that obtains most of its heat from the environment and therefore has a body temperature very close to that of its environment

formation of a bay

military or naval flag

to do away with as completely as if by pulling up by the roots

wearing away of the land, chiefly by rain and running water

a water passage where the tide meets a river current; especially : an arm of the sea at the lower end of a river

the process by which a body of water becomes enriched in dissolved nutrients (as phosphates) that stimulate the growth of aquatic plant life usually resulting in the depletion of dissolved oxygen

disappearance of water by conversion into vapor

similar to bogs but with less acidic soil, due to more ground and surface water. Low shrubs prevail, with some orchids and insect-eating plants.

a substance (such as manure or a chemical mixture) used to enrich the soil and increase plant growth

a place for catching fish; the occupation, industry, or season of taking fish or other sea animals

ships sailing together; vehicles or aircraft under one command or ownership

to wander in search of food

GI Bill
Established after World War II, the GI Bill is a government funded program that help veterans receive money for education and job training. The law also made possible the loan of billions of dollars to purchase homes for millions of veterans, and helped transform the majority of Americans from renters to homeowners.

Refers to a group of species of plants that share certain structural characteristics as determined by botanical study. The genus name, a noun, may come from mythology, literature, or other sources which refer to something the plant resembles.

of or relating to the form or surface features of the earth or other celestial body (as the moon)

gill nets
a flat net suspended vertically in the water with meshes that allow the head of a fish to pass but entangle it at withdrawal; invented circa 800 A.D. and used extensively by Native American fishers in the Great Lakes region. see also seine nets

a large body of ice moving slowly down a slope or valley or spreading outward on a land surface
See also: The Retreat of Glaciers in the Midwestern U.S.

good faith agreement
an agreement based upon honesty rather than enforceable laws

generally parkland, undeveloped open space and agricultural lands, located near the outskirts of towns, cities and larger metropolitan areas.
See also: Great Lakes Greenfields Exchange

plants that have an exposed seed. Examples: conifers and evergreens

a widely distributed mineral consisting of hydrous calcium sulfate that is used especially as a soil amendment and in making plaster of paris

the place or environment where a plant or animal naturally lives and grows

habitat fragmentation
when the place or environment where a plant or animal naturally lives and grows is divided by human development, such as housing divisions, roads, and strip malls. Often connected with urban sprawl.

common salt occurring in solid form as a mineral (rock salt)

heavy metals
Heavy metals, such as lead, copper, iron, and zinc, are naturally found in trace amounts in the earth's crust. However, heavy metals are used extensively in manufacturing and industry (see pesticides), and prolonged exposure can cause deadly health effects. DDT, dioxins and polychlorinated biphenyls (PCBs) are examples of dangerous heavy metals.

relating to or concerned with wholes or with complete systems rather than with the analysis, treatment or dissection of individual parts; example: holistic ecology views man and the environment as a single system

the body or shell (framework) of a ship

offspring of genetically dissimilar parents

the study of the water cycle, both on and below the earth's surface and in the atmosphere

a plot of lake levels versus time

hydroelectric power
of or relating to production of electricity by waterpower

a rolled iron or steel joist (beam like those used in house construction) having an "I" section, with short flanges

ice jam
accumulation of broken river ice caught in a narrow channel, frequently producing local flooding

treating or affecting all equally and fairly

to charge (a public official) before a competent tribunal with misconduct in office

indian corn
a tall widely cultivated American cereal grass (Zea mays) bearing seeds on elongated ears; also maize

International Great Lakes Datum 1985 (IGLD 1985)
benchmark for measuring Great Lakes water levels. referenced to sea level, as measured at Rimouski, Quebec, near the mouth of the St. Lawrence River

tending to spread, infringe or encroach upon

iron ore
rocks or deposits containing compounds from which iron can be extracted

to supply the land with water by artificial means


timber or steel structure along the base of a ship

unit of speed used by ships and aircraft; 1 knot=1 nautical mile/hour (1.852 km/hour), equal to approximately .5 meters/second

Laurentian Mountains
A mountain range located in southern Québec, north of the St. Lawrence River on the southern edge of Canadian Shield.

the act of making laws

a rock that is formed chiefly by accumulation of organic remains (as shells or coral), consists mainly of calcium carbonate, is extensively used in building, and yields lime when burned

littoral transport
the movement of sedimentary material along the shoreline by waves and currents

an enclosure with gates at either end for lifting or lowering vessels from one level to another

longshore transport
littoral transport that is parallel to the shoreline

low-sulfur western coal
coals that typically originate in the western U.S.'s Powder River and Hanna basins, possessing a heating value from 8,700 to 11,500 BTU's per pound as shipped. Other high BTU low-sulfur coals travel to the Great Lakes region from Colorado and Utah. A BTU (British Thermal Unit) is equal to the heat needed to raise the temperature of one pound of air-free water from 60 to 61 degrees Fahrenheit at a constant pressure of 1 standard atmosphere.

molten rock material within the earth from which igneous rock results by cooling

a tall widely cultivated American cereal grass (Zea mays) bearing seeds on elongated ears; also indian corn

type of wetland ecosystem characterized by poorly drained mineral soils and by plant life dominated by grasses

a poisonous heavy metal that is liquid at ordinary temperatures and is used especially in scientific instruments (such as thermometers)

a fabled marine creature with the head and upper body of a man and the tail of a fish

a science that deals with the atmosphere and its phenomena and especially with weather and weather forecasting

minute animals; especially, those invisible to the naked eye

nervous system
a group of organized cells that allow an organism to respond to sensory impulses

New Urbanism
A branch of land-use planning that seeks to redesign towns so that they have a central downtown area, walkable neighborhoods, and public meeting spaces. Often seen as a solution to urban sprawl.

not existing or having not originated naturally in a particular region or environment

nonpoint source pollution (nps)
This type of pollution does not have a specific source (contrary to point source pollution), and is very difficult to regulate. Examples of nps include contaminated runoff and soil erosion.

a science that deals with the oceans including the physics and chemistry of their waters, marine biology, and the exploitation of their resources

oligotrophic having low levels of plant nutrients and an abundant supply of dissolved oxygen. Compare eutrophication

on-offshore transport littoral transport that is perpendicular to the shoreline

to swing backward and forward like a pendulum; to move or travel back and forth between two points

to fish to the detriment of (a fishing ground) or to the depletion of (a kind of organism); to fish until all the fish are gone

Paleozoic Era
A geologic time period that lasted from about 570 to 250 million years ago. The 320-odd million years of the Paleozoic era saw many important events, including the evolution of fish, reptiles, insects, and vascular plants; no less than two distinct ice ages; and, possibly, the formation of the supercontinent of Pangaea.

hypothetical land area believed to have once connected the landmasses of the southern hemisphere with those of the northern hemisphere.
Graphic:This Dynamic Earth, USGS

the supreme legislative body of a usually major political unit, such as the British Parliament

perched dunes
dunes that sit on a plateau high above the shore; they consist of sand as well as other loose material, and dramatically changing lake levels help to create them

Persistent Organic Pollutants
Also known as persistent toxic substances, POPs are chemical substances that persist in the environment, bioaccumulate through the food web, and pose a risk of causing adverse effects to human health and the environment. Some examples of POPs include DDT, PCBs and mercury.

an agent, often toxic to humans, used to destroy pests, such as insects; often used in an agricultural setting

a complex tissue in the vascular system of plants that consists mainly of sieve tubes and elongated cells, functioning in support and storage
See also: xylem

the process by which plants transform energy from the sun into the energy they need to survive

the basic activities that occur in cells and tissues of living organisms

microscopic plants that live in water bodies; since phytoplankton depend upon certain conditions for growth, they are a good indicator of change in their environment

an ancient or prehistoric drawing or painting on a rock wall; one of the symbols belonging to a pictorial graphic system

Pleistocene Epoch
a geologic time period, lasting from 1.8 million to 11,000 years ago, in which the most recent global cooling, or the ice ages, took place

point source pollution
Pollution that can be traced back to a definite source, such as a drainpipe, is called point source pollution (contrary to nonpoint source pollution). Under the Clean Water Act, the Environmental Protection Agency (EPA) has set limitations on point source pollution and has forced companies to obtain permits to discharge pollutants.

polychlorinated biphenyls (PCBs)
Any of several compounds that are produced by replacing hydrogen atoms in biphenyl with chlorine, PCBs have various industrial applications, and are poisonous environmental pollutants which tend to accumulate in animal tissues. The Toxic Substances Control Act (TOSCA) banned the manufacture, processing, and distribution of PCBs, but, due to the longevity of PCBs, we're still feeling their effects today.
See also: Agency for Toxic Substances and Disease Registry

land predominantly made up of grass

water deposits to the earth in the form of rain, sleet, snow, mist or hail

an animal that preys on other animals as a source of food

proglacial lakes
lakes that were created from glacial meltwater

a : a preliminary memorandum often created and signed by diplomatic negotiators as a basis for a final treaty b : the records of a diplomatic conference or congress that show officially the agreements arrived at by the negotiators

one of the most common minerals in the Earth's crust. Made up of silicon dioxide (SiO2), also called silica. Crystals are clear, glassy 6-sided prisms.

red tide
a reddish discoloration of coastal surface waters due to concentrations of certain toxin-producing dinoflagellates [marine plankton]

to replant a forest after it has been cut down, such as for the logging industry

revetment (seawall)
a wall or embankment to protect the shore from erosion or to act as a breakwater

river mouth
the end of a river, or the point at which one river discharges into another body of water (either a river, lake or ocean)

the portion of precipitation on land that ultimately reaches streams, often with dissolved or suspended material (including pollution)

consisting of or containing salt

salmonid (or Salmonidae)
a family of soft-rayed fishes including the trouts, salmons, whitefishes and graylings

sand bar
offshore shoals, built up by wave, current, or wind action; transitory habitat

sand dune
a hill, mound, or ridge of sand and other loose material that is formed by wind action

a sedimentary rock consisting of usually quartz sand united by some cement (such as silica or calcium carbonate)

a treeless plain

seawall (revetment)
a wall or embankment to protect the shore from erosion or to act as a breakwater

Sedimentation occurs when eroded soil is deposited by runoff into rivers, harbors and lakes, degrading water quality and inhibiting navigation

seiche (pronounced "sayshe")
Phenomenon that occurs following a storm surge, when the wind abruptly subsides or barometric pressure changes rapidly on a lake causing the water to oscillate until it stabilizes again

seine nets
a large net with sinkers on one edge and floats on the other that hangs vertically in the water and is used to enclose fish when its ends are pulled together or are drawn ashore; used by Native American fishers, a precursor to gill nets

seventh generation
a belief originating with the Native Peoples that "In our every deliberation, we should consider the impact of our decisions on the next seven generations."

human and animal waste matter carried off by sewers

a fossil rock that is formed by the consolidation of clay, mud, or silt, has a finely layered structure, and is composed of minerals essentially unaltered since deposition

sandy elevations offshore, which may be partially or fully submerged; transitory habitat

sink (referring to pollution)
a lake or wetland can act as a sink for pollutants, where pollutants settle to the bottom and become submerged in soil

Smart Growth
A branch of land-use planning that addresses growth by redirecting public spending away from projects and programs that promote urban sprawl and toward those that revitalize cities and towns

to strike sharply or heavily especially with the hand or an implement held in the hand

a seasonal accumulation of slow-melting packed snow
See also: Compare Great Lakes Snow Melt: 1997-2000

the evolution of a species

The species, an adjective, often refers to a place, the plant's characteristics/appearance, or the name of the person credited with discovering it. Species is abbreviated sp. or spp.

a visible disembodied spirit; ghost

narrow points of land extending into a body of water. May house complex animal and plant communities

rear of a ship or aircraft

storm surge (also known as wind set-up)
phenomenon that occurs when sustained high winds from one direction push the water level up at one end of a lake, which makes the level drop by a corresponding amount at the opposite end

a narrow passageway (usually narrow) connecting two large bodies of water

a grant or gift of money; a grant by a government to a private person or company

suspended solids
organic and inorganic material in the water flow (such as dirt and timber residue); pollutants can attached themselves to suspended solids and settle to the bottom downstream; suspended solids can also make the water murky, affecting aquatic life

suspension bridge
a bridge that has its roadway suspended from two or more cables usually passing over towers and securely anchored at the ends; types of bridges

wetland ecosystem characterized by mineral soils with poor drainage and by plant life dominated by trees

ship, aircraft or vehicle for carrying liquid in bulk

toxic pollutants
Contrary to conventional pollutants, these pollutants are dangerous. Some toxic contaminants, such as sewage, can be treated and then dumped back into the water, while other toxic contaminants, such as heavy metals and PCBs, are too toxic to be treated effectively for water disposal.

an agreement or arrangement made by negotiation; a contract in writing between two or more political authorities (as states or sovereigns) formally signed by representatives duly authorized and usually ratified by the lawmaking authority of the state; or a document in which such a contract is set down

a stream or river flowing into a larger stream, river, or lake

small powerful boat for towing others

machine or motor driven by a wheel that is turned by a flow of water or gas

ultraviolet light
radiation having a wavelength shorter than wavelengths of visible light and longer than those of x-rays

from the Atlantic Ocean

vascular plants
plants that have specialized supporting and water-conducting tissue, called xylem and phloem; these plants typically possess roots, stems, and leaves

animals with backbones, from fish to humans

the time rate of change of position of a body; speed

having a huge appetite; ravenous [very eager or greedy for food, satisfaction, or gratification]

a man employed by a fur company to transport goods to and from remote stations especially in the Canadian Northwest; from Old French "voiage," meaning "to travel"

water that has been used in a manufacturing process, or sewage

floating on or transported by water

water resource policy
the study of the science, engineering, and management of water and related natural resources, and the public policies developed from that research

a region of land that is crisscrossed by smaller waterways that drain into a larger body of water. For example, thousands of creeks, streams and rivers in the midwest ultimately drain into the Great Lakes. The land that these streams and rivers drain from is considered the Great Lakes watershed or basin.

land or areas, usually found around rivers (bog, marsh, swamp) containing much soil moisture; wetlands are important to healthy ecosystems because they are home to a number of critical wildlife and plant species, improve water quality by filtering out sediments and other pollutants, protect the shorelines of rivers and lakes from erosion, and help control and reduce flooding

wind set-up (also known as storm surge)
phenomenon that occurs when sustained high winds from one direction push the water level up at one end of a lake, which makes the level drop by a corresponding amount at the opposite end

woodland land covered with woody vegetation, such as forests

a complex tissue in the vascular system of plants that consists of vessels and wood fibers, conducting water and dissolved minerals, and aiding in support and food storage.
See also phloem


tiny, free-living animals found in the open water of all water bodies; serving as food for fish, they provide an important link in the food chain of aquatic systems

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