Environmental Protection Agency Narragansett Bay Commission University of Rhode Island Office of Marine Programs

Glossary

(Choose a letter to go directly to that section)

A ~ B ~ C ~ D ~ E ~ F ~ G ~ H ~ I ~ J ~ K ~ L ~ M

N ~ O ~ P ~ Q ~ R ~ S ~ T ~ U ~ V ~ W ~ X ~ Y ~ Z



A
ACIDIC
describes a compound or solution with an excess of hydrogen ions. Forms an acid when dissolved in water.

AIR BLADDERS:
the balloon-like pockets of air found on the blades of some heavier seaweed (algae). These air pockets allow the blades to float near the water's surface to capture the sunlight needed for photosynthesis.

ALGAE:
simple 'plants' that have chlorophyll and photosynthesize. They do not have true stems, roots, or leaves. They range from microscopic, single cells (like diatoms) to large, multi-celled forms (like kelp). Single-celled algae are not plants but protists (Kingdom Protista) and many biologists classify all algae in the Protista kingdom.

ANADROMOUS
Animals that spawn in freshwater but live in saltwater, such as salmon.

ANOXIA
the absence of oxygen. Defined as less than 0.5 mg/l dissolved oxygen.

ANOXIC
lacking oxygen.

APPENDAGES
A smaller body part attached to the main body, ie. an arm or leg.

AQUACULTURE:
The growing of fish, shellfish, and marine plants to sell.

AQUATIC:
any organisms that lives in or near the water.

AQUIFER:
an underground area of permeable rock, gravel, or sand that is saturated with water

ARCHAEOLOGY:
the study of ancient people and their cultures as revealed by the items (artifacts) they left behind.

ARTHROPODS:
invertebrates of the phylum Arthropoda that have jointed appendages and a chitinous, segmented exoskeleton. Arthropods include insects, spiders, crabs, and lobsters.




B
BACTERIA (IUM):
single-celled microorganisms that belong to the kingdom Monera. Bacteria are among the smallest, simplest, and oldest types of cells.

BALLAST WATER:
Water that is used to stabilize large transporter ships and is discharged at various points on their routes; the water typically contains a variety of species which become invasive species when discharged into non-native waters.

BAR-BUILT ESTUARY:
Formed when sandbars build up along the coastline and partially cut off the waters behind them from the sea.

BARNACLE ZONE:
one of the life zones on the rocky shore; also called the white zone for the color of the barnacles that dominate this part of the shore. This zone is exposed to air for about half of the day.

BASIC
describes a compound or solution with an excess of hydroxide (OH) ions. Forms a base when dissolved in water.

BENTHOS:
Organisms that lie in and on the bottom of the ocean floor.

BIOAVAILABILITY
the availability of a pollutant to be used by living organisms.

BIVALVE:
the type of mollusk (Phylum Mollusca) that has two hinged shells (valves). Bivalves include clams, mussels, and scallops.

BLADE:
the flattened or leaf-like part of the body of an alga.

BLOOM:
High concentration of phytoplankton in an area, caused by increased reproduction; often produces discoloration of the water.

BYSSAL THREADS:
the strong fibers that mussels produce to attach themselves to rocks or hard surfaces.




C
CAMOUFLAGE:
a means of disguise that allows organisms to blend in with their background so that they are hidden or concealed.

CALCAREOUS:
having a hard, crust-like covering composed of calcium carbonate.

CALIBRATE
to adjust an instrument.

CAPPING:
Contaminated spoils covered with clean sediments to isolate the contaminated material from the surrounding sea life and water.

CARAPACE:
A hard outer covering such as a shell.

CARPOSPOROPHYTE:
a stage in the life cycle of red algae, this small rounded bump remains attached to the female gametophyte. This structure, when mature, bears carpospores; also called a cystocarp.

CELSIUS
a temperature scale in which the fixed points are the temperatures at standard pressure of ice at 0 degrees and of steam at 100 degrees. Abbreviated C.

CG-CM:
Canadian Global Coupled Model.

CHLOROPHYLL
pigment responsible for the green color in plants. The molecules are primary sites of light absorption in photosynthesis.

CNIDARIA:
phylum of aquatic invertebrates (formerly called Coelenterata) that includes Hydra, jellyfish, sea anemones, and corals. These animals have stinging cells on their tentacles and can occur in different body forms. They may be free-swimming medusa and/or attached polyps hydroids).

COASTAL PLAIN ESTUARY:
An estuary formed at the end of the last ice age. Ice melted, water warmed, and sea level rose invading the low-lying coastal river valleys.

COENOCYTIC:
having many nuclei not separated into individual cells.

COLORIMETRIC
an analysis of solutions by estimating their color by comparing them with standard colors of known solutions.

CONCENTRATION
the quantity of a dissolved substance in a solution.

CONCEPTACLE:
a small cavity on the surface of an alga that contains reproductive structures.

CONDUCT
to transfer electricity through matter.

CONDUCTIVITY
a measurement of the ability to transfer electricity through matter.

CONTAINER PORT:
a port used by large vessels for the import and export of goods.

CRUSTACEANS:
a class of mainly aquatic, gill-breathing arthropods such as crabs, lobsters, shrimp, and barnacles. They usually have a hard exoskeleton and two pairs of antennae.

CSOs:
Combined Sewer Overflows.

CTENOPHORE:
another name for comb jellies (Phylum Ctenophora). These marine animals have a gelatinous body and no backbone. Even though they look similar to jellyfish (Cnidarians), they do not have stinging cells. They get their name from the 8 rows of cilia that look like combs.




D
DECOMPOSE:
to rot or break down in decay.

DEGREE
a division on a temperature scale.

DENSITY
mass of a substance per unit volume (i.e. pure water has a density of 1 gram per milliliter).

DEPOSIT FEEDERS:
organisms that ingest or sift through the sediment and consumes organic matter within it.

DETRITUS:
Organic or inorganic debris.

DICHOTOMOUS:
splitting into two.

DISSOLVED OXYGEN:
oxygen molecules (O2) dissolved in water.

DIURNAL TIDE:
a tidal cycle where there is one high tide and one low tide in one lunar day (lunar day = 24 hours, 50 minutes).

DREDGING:
the removal of sediments from an estuary's floor.




E
ECHINODERMS:
a large group of invertebrates that have radial symmetry and no heads (Phylum Echinodermata). All are marine and benthonic (live on or in the bottom). They have an internal skeleton and a special network of water-filled canals that move their tube feet. Sea stars, sea urchins, and sea cucumbers are all echinoderms.

ECOSYSTEM:
all the living and nonliving things that interact within a certain area; a web of life.

EDC:
Economic Development Council.

EFFLUENT:
discharge of waste from a sewer or sewage system.

EIS:
Environmental Impact Study.

ELECTRICITY
an effect resulting from the existence of stationary or moving electric charges.

EPIPHYTE:
a plant or alga growing on another plant or alga.

ESTUARY:
a semi-enclosed body of water where freshwater meets and mixes with saltwater. Narragansett and Chesapeake Bays are both examples of estuaries.

EUTROPHICATION:
the process of polluting a body of water with excessive nutrients, such as sewage or fertilizers. The nutrients cause an excessive growth of algae that leads to oxygen being depleted from the water (result of the decomposition of the algae).

EVAPORATE
to form a gas (vapor) from a liquid.

EVAPORITE DEPOSITS
deposit formed from minerals left behind by evaporating water, especially salt.

EXOSKELETON:
external skeleton; the hard skeleton that forms the external surface of some animals. The exoskeleton protects, supports, and provides a place for muscles to attach. Some mollusks, tortoises, and arthropods (such as crabs, lobsters, barnacles, and shrimp) have exoskeletons.




F
FAHRENHEIT
a temperature scale in which boiling of water takes place at 212 degrees and freezing of water occurs at 32 degrees. Abbreviated F

FASCICLE:
a bundle of branches that arise from a common point .

FAUNA:
the animals that live in a specific environment or place.

FECAL MATERIAL:
solid wastes produced by animals.

FILTER FEEDERS:
Organisms which take water in and filter out food; during this process, sediments and pollutants are also filtered out thus cleaning the water.

FJORD:
alleys that have been cut deeper by moving glaciers and then invaded by the sea. Fjord estuaries have a deep elongated basin that is U-shaped and a ledge or barrier that separates the basin form the sea.

FLORA:
the plants that live in a specific place or environment.

FLUORESCE
the emission of light by a substance.

FLUOROMETER
an instrument that measures the emission of light from a substance.

FOLIOSE:
having a leafy appearance.

FOSSIL:
the remains or traces of organisms.

FOSSIL FUEL:
the hydrocarbon remains of plants or animals that have been changed by natural processes; oil, coal and natural gas.

FRY:
recently hatched fish; very young fish.

FUCOID:
alga relating to or resembling the rockweeds.




G
GASTROPODS:
one-shelled mollusks (Phylum Mollusca, Class Gastropoda). These univalve invertebrates have a coiled shell, a flattened foot, and a well developed head with tentacles. Snails, limpets, conchs, whelks, and slugs are all gastropods.

GAMETE:
a mature male or female germ cell.

GAMETOPHYTE:
the phase of the life history that produces gametes.

GCMs:
general circulation models.

GEOLOGY:
the study of the origin, structure, and composition of the earth.

GIS:
this abbreviation stands for Geographic Information System. GIS is a combination of computer software and hardware tools used for creating maps and analyzing spatial data. GIS links the map and database information so that questions can be asked and answers given in map or visual form.

GLACIER:
A large, permanent mass of ice .

GLOBAL WARMING:
An increase in Earth's average temperature caused by the greenhouse effect.

GREENHOUSE EFFECT:
The trapping of heat in the atmosphere; caused by gases such as carbon dioxide and methane.

GREENHOUSE GASES:
the gases responsible for the greenhouse effect such as carbon dioxide and methane.

GROUNDWATER
water beneath the ground that has seeped into the soil and rock from above.




H
HABITAT:
the place or environment where a plant or animal lives.

HEAVY METALS:
metallic elements such as cadmium, lead, mercury, nickel, arsenic, and selenium, and their compounds.

HOLDFAST:
the root-like part of a seaweed. The holdfast attaches the seaweed to a hard surface.

HEAT
the process of energy transfer from one body or system to another as a result of difference in temperature.

HEAT CAPACITY
the quantity of heat required to produce a 1 degree Celsius change of temperature in one gram of material.

HYPOXIA
a deficiency in oxygen. Defined as less than 3.0 mg/l dissolved oxygen.

HYPOXIC
deficient in oxygen.




I
INTERTIDAL:
area of the shore between the highest and lowest tides.

INVASIVE SPECIES:
A species that does not naturally occur in a specific area and whose introduction does or is likely to cause economic or environmental harm or harm to human health.

INVERTEBRATES:
animals without a backbone. At least 97% of all animal species are invertebrates; with the exception of insects, most invertebrates are marine species.

ION
positively or negatively charged atom or group of atoms.

IPCC:
International Panel on Climate Change.

IRISH MOSS ZONE:
one of the life zones of the rocky shore. This lower intertidal area is submerged most of the time and is exposed to the air only during very low tides. This zone is dominated by the red algae, Irish moss.




J



K
KELP ZONE:
the lowest or most seaward life zone of rocky shore. This zone is always submerged and extends seaward as far as light can penetrate. The kelp zone is identified by the large, leathery, brown kelp that grows there.

KELVIN
a temperature scale used by scientists where 0 Kelvin is -273 degrees C. Abbreviated K




L
LAGOON:
a shallow, sheltered body of water that is separated from the sea by a barrier island, sand bar, or coral reef.




M
MANTLE (in zoology):
the fold of skin covering the top of a mollusk body. The outer surface of the mantle secretes the shell.

MEDULLA:
the inner layers of cells; colorless and may function in storage.

MIDRIB:
a strip or thickening that runs up the center of a blade.

MIGRATE:
the periodic or regular movement of animals from one place to another. Often animals migrate to feed or breed.

MINNOW TRAP:
a specialized trap or enclosure to capture small fish, such as minnows, by attracting them to the bait in the trap.

MOLLUSKS:
invertebrates in the Mollusca phylum; these animals have a soft, unsegmented body and are bilaterally symmetrical. Most have a muscular foot, calcareous shell, and gills. This phyla includes terrestrial as well as fresh and salt water forms. Common examples are clams, snails, slugs, and octopuses.

MOLT:
to periodically shed hair, feathers, outer skin, or horns with the cast off parts being replaced by newly grown replacements.

MUDFLAT:
a muddy flat intertidal area that is covered by water at high tide and exposed to the air at low tide. Mud flats form at the edge of salt marshes or at the mouths of estuaries.




N
NEAP TIDE:
tides occurring near the first and last quarter moons of each month when the range of the tide is the least.

NEKTON:
free swimming organisms that are capable of moving through the water at will.

NON POINT SOURCE POLLUTION:
occurs when a pollutant is from a source that is not so easily identifiable such as water runoff. Example: run-off during a rainstorm may cause contamination from fertilizers onto the surface of the bay.

NUCLEI:
the control centers of cells .

NUTRIENTS:
organic or inorganic compound that is used by plants in primary production. Examples: nitrogen and phosphorus compounds.




O
OMNIVORE:
Eating both plants and animals.

OPERCULUM:
A lid or flap of skin covering an opening. Examples are the flap of skin covering the gills of some fish and the hard calcite cover of the snail shell opening when the snail is drawn up inside the shell.

ORGANIC MATTER:
Compounds that are or were once part of a living organism or produced by a living organism.

ORGANISM:
any living individual, whether it is a protist, plant, or animal.




P
PARENCHYMATOUS:
a description of a organism that has developed in three dimensions, caused by cell divisions.

PARTIALLY MIXED ESTUARY:
An estuary where the salt water is mixed upward and fresh water is mixed downward.

PART PER THOUSAND
a unit of salinity where 35 parts per thousand is equal to 35 grams of salt in 1000g of seawater. Abbreviated ppt

PATHOGENS:
any microscopic organism that can cause a disease.

PELAGIC:
organisms that swim or drift in the water, these organisms are distinct from those living on the bottom.

PERICARP:
this structure encloses the carposporophyte and is formed by a layer of cells from the female gametophyte.

PERIWINKLE ZONE:
the second highest (from land) life zone found on the rocky shore. Periwinkles are abundant in this part of the rocky intertidal shore but since they are mobile, this zone is often indistinct. For this reason, some biologists don't include this as one of the life zones on the rocky shore.

pH
the measure of concentration of hydrogen ions in solution. This concentration determines the acidity of the solution.

PHOTOSYNTHESIS:
A process where plants use the sun's energy to combine carbon dioxide and water into simple foods.

PIGMENT
a compound that gives color to a tissue and has a variety of functions.

PLANKTON:
pelagic organisms that drift or float passively in the water and are carried wherever currents and tides take them. Plankton are often microscopic and are an important food source for other aquatic community. There are two types of plankton- phytoplankton (plants and autotrophs) and zooplankton (animals).

PLATE TECTONICS:
theory and study of Earth's lithospheric plates, their formation, movement, interaction, and destruction; the attempts to explain Earth's crustal changes in terms of plate movements.

POINT SOURCE POLLUTION:
occurs when a pollutant is discharged at a specific source, the source can be easily identified. Example: Leaking pipe, the cause of pollution can be observed.

POLYCHAETE:
annelid or segmented worms that have flat extensions with stiff, sometimes sharp, bristles sticking outward from each body segment (Phylum Annelida, Class Polychaeta). Most marine worms are polychaetes.

PORTS:
Physical Oceanographic Real-Time System.

PRECIPITATE
a suspension of small solid particles produced in a liquid by a chemical reaction.

PREDATOR
An animal that preys upon others.

PREY
An animal hunted or caught for food.




Q
QPP:
Quonset Port Partners.




R
RECEPTACLE:
the swollen or inflated portion of a branch or branch tip found on Fucoids. These inflated branches may have conceptacles on them.

RED TIDE:
red coloration, usually of coastal waters, caused by large quantities of phytoplankton; some red tides are caused by polluted waters, other are not.

REFRACTION
change in direction, or bending of a wave.

REFRACTOMETER
any of various instruments used to measure the refraction of a substance or medium.

REFUGE:
shelter or protection from danger.

RESISTANCE
a measure of opposition to the flow of electrical charge.

RESTORATION:
the act of bringing something back to its original state.

RIFW:
Rhode Island Fish and Wildlife.

ROCKWEED ZONE:
a life zone at the intertidal area of a rocky shore. This life zone is submerged at every high tide and is dominated by brown seaweed, such as knotted wrack and rockweed. For this reason this zone is often called the brown zone.

RUN-OFF:
water from rain, melted snow or agricultural or landscape irrigation that flows over the land surface and discharges to surface waters.




S
SALINITY:
the total amount of salt dissolved in seawater; the units most often used are parts per thousand (ppt) but practical salinity unit (psu) is now the accepted standard in oceanography. An average salinity value for seawater is 35 ppt (psu) or 35 parts of salt in 1000 parts of water.

SALT
crystaline ionic compounds such as NaCl.

SALT POND:
New Englander's term for a coastal lagoon; a body of salt or brackish water that is located behind a barrier beach or island and is connected to the sea by a natural (temporary) or man-made (permanent) opening called a breachway.

SALT WEDGE ESTUARY:
Occurs when the mouth of a river flows directly into salt water.

SATURATED
containing the maximum amount of a dissolved substance at a given temperature.

SCAVENGER:
An animal that feeds on dead or decaying matter.

SEA-LEVEL:
level of the sea surface; used as a reference for measuring height on land or depth in the ocean.

SEAWEED:
any of the larger (multicellular) forms of algae that live in the ocean.

SEDIMENT:
particulate organic and inorganic matter that accumulates in loose, unconsolidated form.

SEINE:
rectangular net used to collect fishes or other animals from shallow water; also called a beach seine. One of the long sides of the net is weighted and the other long side has floats. The net is pulled through the water by the short sides so that the side with floats rides on the surface and the weighted side moves along the bottom.

SEMIDIURNAL TIDE
a tidal cycle where there are two high tides and two low tides in one lunar day (lunar day = 24 hours, 50 minutes).

SEPTIC SYSTEM:
an underground system that breaks down sewage from homes. Septic systems are used where homes are not hooked up to a city (municipal) sewer system. The system includes a septic tank where solid sewage is broken down by bacteria and a leach field into which water flows from the tank.

SESSILE:
an animal that lives permanently attached to the bottom or to a surface.

SIPHON:
a tube like structure used by organisms for drawing in or forcing out water.

SMOG:
An atmospheric condition in which visibility is reduced due to air pollution that contains high levels of particulates or photochemical oxidants.

SOLUBILITY
the amount of solute that dissolves in a solvent to form a solution usually depends on temperature.

SPECIES:
a group of similar individuals that can breed among themselves. A biological category used to classify organisms.

SPRING TIDES:
tides of greater than average tidal range that occur twice a month at the new and full moons.

SPOROPHYTE:
the phase of the life history that produces spores.

STIPE:
The "stem" of the organism. May be cylindrical or flattened. Function not specialized for transport as in plant stems.

SUBTIDAL:
the area of the shore bottom that is always covered by water and is never exposed at low tide.

SUPERSATURATION
the state of a solution where the concentration of the dissolved substance exceeds the equilibrium concentration at that temperature.




T
TECTONIC ESTUARY:
formed when the sea fills in the "hole" or basin that was formed by the sinking of land due to folding and faulting in the Earth's crust.

TEMPERATURE
the property of a region or body which determines whether or not there will be a flow of heat into or out of the body.

TERRESTRIAL:
organisms living or found on land.

TETRASPORE:
a reproductive spore produced by some red algae.

THALLUS (thalli, pl.):
a simple plant body, such as multicellular algae, that is not differentiated into stem and leaves.

THERMISTOR
a device that measures temperature by measuring the resistance to electric flow in a metal as the temperature changes.

THERMOMETER
an instrument used to measure the temperature of a substance.

TIDE:
the daily rising and falling of the ocean's surface. This change in the water's height is caused by the combined gravitational pull of the moon and sun on the Earth's surface.

TIDE CHART:
a list showing the times each day when the tide will be high or low.

TIDE POOL:
a low spot in the rocks or sand that holds seawater when the tide is out.

TITRATION
a method of volumetric analysis in which an amount of one agent is added to a known amount of another slowly from a burette in order to reach a point of equal acidity. Used to calculate an unknown volume from a known volume of liquid.

TRAWLING:
A process where nets are towed through the water by boats to collect sea life.

TUNICATE:
marine invertebrates that are also chordates (Phylum Chordata). They have a sac-like body and don't move because they attach to the bottom or a surface (like boats and docks). They're commonly called sea squirts.




U
UNEP:
United Nations Environment Programme.

UNISERIATE:
one row.

UNIVALVE:
a one shelled mollusk; gastropod.




V
VECTOR BORNE DISEASE:
a disease that is spread by non-human organism such as a tick, to a human being.

VERTEBRATE:
animals with backbones (vertebral columns) and whose brain is encased in a skull; Vertebrata is in the largest subphylum of Chordata.

VIRUS:
A very small particle made up of nucleic acid with a protein covering, or protein coat; not cells but can reproduce in the cells of living organisms.

VOCs:
Volatile Organic Compounds.




W
WAMPUM:
beads made from two types of shells. The white beads were made from Northern whelk shells and the purple beads were made from quahog (clam) shells.

WATER POLLUTION:
The change to water that is harmful to organisms.

WATERSHED:
a region or area drained by a particular body of water.

WEATHERING:
the processes that decay or break up rocks by a combination of physically fracturing or chemically decomposing them.

WELL-MIXED ESTUARY:
An estuary with strong tidal mixing and low river flow that mix the sea water throughout the shallow estuary. Salinity is the same top to bottom and decreases from ocean to river.

WETLANDS:
areas that are covered by water at least part of the year. These areas have a specific type of soil, can be covered by either fresh or salt water, and are heavily vegetated.

WMO:
World Meterorological Organization.




X



Y



Z
ZONATION:
series of life zones that indicate the presence of organisms within a particular range of time or space.

ZONE:
a geographic area where only certain organisms live.




Please address comments and questions
to Gail Scowcroft at gailscow@gso.uri.edu.


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