Glossary

	A
	An acid is a substance that has a pH of less than 7, which is neutral.
	Aerobic refers to something occurring, acting or living only in the presence of oxygen.
	Algae are simple, rootless plants found in natural waters that grow in relative proportion to the amount of nutrients available. Sudden growth spurts , or blooms, can adversely affect water quality.
	Anaerobic refers to something happening in the absence of oxygen.
	An anion is a negatively charged ion.
	Anthropogenic: human related
	An aquifer is a geologic formation that is water bearing. It includes structures that store and/or transmits water, such as to wells and springs. Use of the term is usually restricted to those water bearing formations capable of yielding water in sufficient quantity to constitute a usable supply for people's purposes.
	An atom is the smallest whole unit of a chemical element.

	B
	Benthic refers to the bottom of a body of water.
	Benthos refers to bottom dwelling organisms.
	Biomass includes the total weight or volume of all living things found in a defined location.
	Biota is the living matter of an area.
	Brackish waters refer to bodies of water that are between fresh water (0 to 10 parts per thousand salt) and marine waters (35 parts per thousand salt.)
	Brine refers to a salty solution similar to that of ocean water usually found in water softeners.
	A buffer is a substance to which small amounts of acids or bases are added which when added to another solution prevents appreciable changes of pH of the solution.

Top	C
	Carotenes are pigments that produce a yellow to orange color in plants.
	A cation is a positively charged ion.
	A catalyst is a substance that causes a change in the rate of a chemical reaction without being consumed by the reaction.
	Centrifugation is a process in which substances are spun very rapidly forcing heavier materials to the bottom of the container.
	Chlorine is the mainstay of disinfection in the U. S. water system. It kills many bacteria, but not all.
	Chlorophyll is the green light trapping pigment essential as an electron donor in photosynthesis.
	Coagulation is the process in which a chemical is added to a solution (water in this case) and the chemical causes the impurities to clump together for easy removal.
	A colloidal state represent properties that are intermediate between those of an ordinary suspension and those of a true solution.
	Colorimetric determination is the process by which a specific compound is analyzed on the basis of its ability to react with another chemical and change color. The color is then measured on an instrument using a controlled light source which can distinguish small differences in color.
	A compound is a pure substance that can be broken down by chemical means into two or more simpler substances.
	Condensation is the process of water vapor in the air turning into liquid water. Water drops on the outside of a cold glass of water are condensed water. Condensation is the opposite process of evaporation.
	Consumers are organisms that cannot make their own food and must obtain energy by eating other living things

Top	D
	Decomposers include organisms such as bacteria and fungi that break down plant and animal remains into forms once again usable by producers.
	Denitrification is the process by which nitrates are converted to ammonia and molecular nitrogen as by denitrifying bacteria.
	Disinfection is the process by which chemicals are added to water to reduce bacterial contamination
	Distillation is the process by which water is boiled to make steam which is then collected and condensed for drinking. It is an expensive way to purify water.
	Detritus is the decaying organic matter found on the bottom of lakes and streams.
	Discharge of streams and rivers is the volume of water passing a certain point along a stream or river at a given period of time.
	DNA is the abbreviation for deoxyribonucleic acid.
	Duplicate is usually the smallest number of replicates(two).

Top	E
	Ecology is the study of the interactions between living things and their environment.
	An ecosystem includes all of the biotic and abiotic components of a given area.
	An element is a substance that can not be broken down into a more simple substance. Each element is represented by a symbol. A group of elements is represented by the first capital letter in the name of the element. For the others, the symbol consists of the first capitalized letter in the name of the element followed by an appropriate second letter.
	Endemic refers to a plant or animal that is naturally found in an area.
	The epilimnion is the upper stratum of more or less uniformly warm, circulating and fairly turbulent water. (Greek epi = on, limne = lake)
	Equilibrium is the state in which chemical and physical elements of a system are balanced.
	Euphotic or photic is the lighted and well mixed portion of the lake which extends from the lake surface down to where the light is about 1% of that at the surface. (Includes most of the epilimnion.)
	Eutrophic are waters with a good supply of nutrients and hence a rich organic production. (Greek eu = well, trophien = to nourish)
	Evaporation is the process of liquid water becoming water vapor, including vaporization from water surfaces, land surfaces, and snow fields, but not from leaf surfaces.

Top	F
	Facultative anaerobic bacteria are bacteria that use oxygen when it is available, but are also capable of fermentation.
	Fecal Coliforms are species of bacteria that are present in the digestive tracts of humans and other warm-blooded animals. These are not disease producers, but great numbers of these bacteria indicate unsanitary conditions where disease-causing organisms may also be present.
	Fermentation is the chemical process by which a sugar is turned into an alcohol, releasing energy.
	A food chain is a way of showing how nutrients and energy pass from producers through the various trophic levels in an ecosystem at any given time, moving from producers up the food web to top-level consumers.
	A food web is the integration of many food chains existing in an ecosystem showing the complex, interwoven pathways of energy flow between the organisms living in that environment.
	Fucoxanthin is a brownish pigment found in diatoms, brown algae and dinoflagellates.

Top	G
	Gram-negative bacteria have an outer cell wall consisting of lipopolysaccharides and proteins and do not retain crystal violet stain, but are colored red by the counter stain, safranin.
	Ground water is water that flows or seeps downward and saturates soil or rock, supplying springs and wells. The upper surface of the saturate zone is called the water table. Also, it refers to water stored underground in rock crevices and in the pores of geologic materials that make up the Earth's crust.

Top	H
	A habitat is the kind of environment in which a certain organism normally lives.
	HCl is the symbol for hydrochloric acid.
	HNO₃ is the symbol for nitric acid.
	H₂SO₄ is the symbol for sulfuric acid.
	Hydrologic cycle is the cyclic transfer of water vapor from the Earth's surface via evapotranspiration into the atmosphere, from the atmosphere via precipitation back to earth, and through runoff into streams, rivers, and lakes, and ultimately into the oceans.
	Hydrolyzation is the decomposition of a chemical by the addition of water.
	Hypolimnion is the lower stratum of deep, cold relatively undisturbed water, lying below the epilimnion. (Greek hypos = under, limne = lake)

Top	I
	An inorganic anion is a negatively charged ion that contains no carbon atoms.
	Inorganic compounds are substances that do not contain carbon.
	An ion is an electrically charged atom or group of atoms.
	In situ is from the Latin meaning in its original site or position. Usually, it refers to an experiment conducted in the lake as opposed to in the laboratory.
	Invertebrates are animals that lack segmented vertebral columns.

Top	L
	Lactose fermenting bacteria are bacteria which will turn lactose (a sugar) into an alcohol.
	Leaching is the process by which soluble materials in the soil, such as salts, nutrients, pesticides chemicals or contaminants, are washed into a lower layer of soil or are dissolved and carried away by water.
	Lentic refers to standing water such as in ponds or lakes.
	Limnology is the study of inland waters. (Greek limne = lake, logos = discourse)
	A limnologist is a person who studies inland waters.
	Littoral is the shore area of a lake encompassed between the highest seasonal water levels and the maximum depth of rooted vegetation. (Latin litus = shore)
	Lotic refers to running water as found is streams or rivers.

Top	M
	A macrophyte is a form of aquatic vegetation (i.e. water weeds) large enough to be seen by the unaided eye.
	Mesotrophic is a state of lake productivity characterized by moderate levels of nutrients, moderate growth and imtermediate levels of oxygen.
	The metalimnion is thermal layer that forms if lakes during the warm season. It is the intermediate layer between the upper warm layer (epilimnion) and the colder lower layer (hypolimnion).

	N
	Non-spore forming bacteria are bacteria that do not form spores in their reproductive cycle.
	Nutrients are any of a group of elements necessary for growth. Although over 15 elements have been identified as necessary; for the growth of aquatic plants, phosphorus is usually the limiting nutrient in Michigan surface waters.

	O
	Oligotrophic is a state of lake productivity characterized by clear water, low nutrient levels and high oxygen levels.
	Organic compounds are substances that contain carbon.
	Osmosis is the movement of water molecules through a thin membrane.
	An oxidizing agent is a substance, which causes another element or compound to go from a lower to a higher oxidation state. An example is found when oxygen combines with iron to form rust.

Top	P
	Photosynthesis is the process by which plants form carbohydrates from carbon dioxide and water, mediated by sunlight on chlorophyll. (Greek phos, photos = light + synthesis = placing together)
	Phycobilins are red and blue pigments found in blue-green and red algae. (Greek, phykos = seaweed + Latin, bilin = bile)
	Phycoerythrin is the red pigment found in red algae. (Greek, phykos = seaweed = erythros = red)
	Phytoplankton are microscopic plants that are free floating in the open water. (Greek, phyton = plant + planktos = wandering)
	Phytoplankton biomass is the weight of the living phytoplankton in a given area.
	Plankton is usually a small freely floating group of organisms (plants and animals). (Greek, planktos = wandering)
	Potable water is water that is suitable to drink.
	Precipitation refers to the direct falling of a substance (rain, snow, dust, etc.) onto a body of water. In an aqueous solution, it can refer to the settling out of a substance due to a chemical reaction or a state of supersaturation.
	Primary producers include green plants and others that are capable of changing inorganic elements into organic tissue (food energy).
	Pyrite oxidation is the chemical reaction that occurs between oxygen and pyrite. Pyrite, commonly known as fool's gold, is widely distributed in rock of all ages and is used chiefly as a source of sulfur for sulfuric acid.

Top	R
	A reducing agent is a substance which causes another element or compound to go from higher to a lower oxidation state in a chemical reaction.
	Respiration is the process during which organisms metabolize food molecules to get energy for growth and maintenance, consuming oxygen and giving off carbon dioxide.
	Riparian refers to organisms or items located along the edge of a stream or river.
	RNA is the abbreviation for ribonucleic acid.

Top	S
	Sedimentation occurs in lakes or streams during the natural decaying processes of plants and animals in which the decaying matter settles to the lake or stream bottom.
	A solution is a substance which contains another substance that is completely dissolved.
	A stream is a body of flowing water.
	Surface water is water from rivers and lakes
	A suspension is a mixture of finely divided insoluble substance which appears cloudy or turbid. On standing, however, the mixture soon becomes clear as the particles settle out to the bottom.
	T
	Transpiration is the process by which water that is absorbed by plants, usually through the roots, is evaporated into the atmosphere from the plant surface, such as leaf pores.
	A tributary is a smaller river or stream that flows into a larger river or stream. Usually, a number of smaller tributaries merge to form a river.
	Turbidity is a measure of the ability of light to penetrate water.

	V
	Vertebrates are animals that possess segmented vertebral columns.

Top	W
	Wastewater is water that has been used in homes, industries and business that is is not for reuse unless it is treated.
	Water quality is a term used to describe the chemical, physical and biological characteristics of water, usually in respect to its suitability for a particular purpose.
	The water table is top of the water surface in the saturated part of an aquifer.
	A watershed is the land area that drains water to a particular stream, river or lake.

	X
	Xanthophylls are a group of yellow pigments found in plants. (Greek, xanthos = yellow + phyllon = leaf)

	Z
	Zooplankton are small animals with limited powers of locomotion, suspended in water. They are usually denser than water and constantly sink by gravity to lower depths. (Greek zoion = animal + planktos = wandering)


Page last updated on 17 February 2003
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