Glossary

Acid Rain: Rain with a pH of less than 5.6; results from atmospheric moisture mixing with sulfur and nitrogen oxides emitted from the burning of fossil fuels; may cause damage to buildings, crops, forests, and aquatic life.

Acidic: Having a pH value less than 7.0.

Algae: Any of various primitive, chiefly aquatic, one-celled or multicellular plants that lack true stems, roots, and leaves but usually contain chlorophyll. Included among the algae are kelps and other seaweeds, and the diatoms.

Algae bloom: A proliferation of algae in a body of water often associated with excess nutrients (especially phosphorus and nitrogen) in the water column and/or sediments.

Alkaline: Having a pH value greater than 7.0.

Aquifer: Porous layer of underground rock that contains groundwater.

Atmospheric deposition: Particles from the atmosphere deposited on the earth's surface either in wet or dry form.

Bacteria: Single-celled organisms that do not possess chlorophyll.

Basin: Geographic land area draining into a lake or river; also referred to as drainage basin or watershed.

Benthic: Refers to being on the bottom of a lake.

Best Management Practices: An engineered structure or management activity, or combination of these, that eliminates or reduces adverse environmental effects of pollutants.

Bioaccumulation: A process whereby certain chemicals become more highly concentrated in the bodies of organisms higher in the food chain.

Bioassay: A biological test using a living organism such as an animal or plant. Bioassay is often used to test for toxic substances

Channelization: The cutting or manicuring of river channels, or direction by way of a channel.

Chlorine: A widely used disinfectant in waste treatment plants, drinking water, and swimming pools.

Combined Sewer: A sewer system by which both storm water and sanitary wastes are transported by the same pipe to a sewage treatment plant.

Compost: A mixture that consists largely of decayed organic matter used for fertilizing and conditioning land.

Decomposition: The breakdown of organic matter by bacteria and fungi.

Dioxin: Chlorinated organic compounds with low water solubility that bind to sediment and soil particles and concentrate in fatty tissues. Dioxins bioaccumulate moderately in the aquatic environment. They are by-products of incomplete combustion in the presence of chlorine and are found in fly ash and other products of these processes.

Dissolved Oxygen (DO or O2): The concentration of free (not chemically combined) molecular oxygen (a gas) dissolved in water, usually expressed in milligrams per liter, parts per million, or percent of saturation. Adequate concentrations of dissolved oxygen are necessary for the life of fish and other aquatic organisms and the prevention of offensive odors. DO levels are considered the most important and commonly employed measurement of water quality and indicator of a water body's ability to support desirable aquatic life. Levels above 5 milligrams per liter are often referred to as hypoxic and when O2 is totally absent anoxic (often called anaerobic which technically means without air).

Drainage Basin: See Basin

Dredging: Removal of earth from the bottom of waterways in order to create and maintain channels, canals, and marinas or to obtain deposits of sand, gravel, and shells, for construction materials. Dredging is also used to "clean up" contaminated sediment.

Ecosystem: All of the interacting organisms in a defined space in association with their interrelated physical and chemical environment.

Effluent: A discharge of liquid waste.

Environmental Protection Agency (EPA): A United States agency responsible for managing federal efforts to control air and water pollution, solid waste disposal, radiation and pesticide hazards, and other environmental concerns.

Epilimnion: The upper, wind-mixed layer of a lake. This water is turbulently mixed throughout at least some portion of the day and because of its exposure, can freely exchange dissolved gases (such as O2 and CO2) with the atmosphere.

Erosion: The wearing away of land surfaces by wind or water. This process occurs naturally, but can be greatly intensified by land clearing activities. Erosion of soil along stream banks can cause streams and rivers to appear brown, and sometimes cause problems for fish and wildlife.

Escherichia coli (E. coli): A specific coliform bacteria used as an indicator organism of pathogens in fecal coliform testing.

Eutrophication: A process of nutrient (mainly phosphorus and nitrogen) enrichment whereby water bodies gradually become more densely populated with vegetation and algae.

Evaporation: The process of converting liquid to vapor.

Fecal Coliform Bacteria: A group of organisms found in the intestinal tracts of people and animals. Their presence in water indicates pollution and in large numbers may pose a health hazard.

Food Chain: The transfer of food energy from plants through herbivores to carnivores. An example: the sequence of algae being eaten by zooplankton (grazers; herbivores) which in turn are eaten by small fish (planktivores; predators) which in turn are eaten by larger fish (piscivores; fish eating predators) and eventually by people or other predators (fish-eating birds, mammals, and reptiles).

Food Web: Food chains hooked together into a complex interconnected web.

Grasscycling: Grasscycling means leaving the grass clippings on your lawn after you mow instead of raking and bagging them. This enriches your lawn with important nutrients, reducing or eliminating the use of commercial fertilizer. New York State has banned grass clippings from being accepted at landfills to conserve valuable space.

Groundwater: Water that infiltrates into the earth and is stored in the soil and rock below the earth's surface.

Heavy Metals: Metallic elements like zinc, mercury, chromium, cadmium, arsenic, and lead, with high molecular weights. They can damage living things at low concentrations and tend to accumulate in the food chain.

Household hazardous waste: Any substance that ignites easily, reacts or explodes when mixed with other substances or is corrosive or toxic. Many home and garden products are considered hazardous and contain potentially dangerous chemicals that must be disposed of with special care.

Hydrology: The study of water's properties, distribution and circulation on Earth.

Hypolimnion: The bottom, and most dense layer of a lake. It is typically the coldest layer in the summer and warmest in the winter. It is isolated from wind mixing and typically too dark for much plant photosynthesis to occur.

Impervious surfaces: Land surfaces such as roads, parking lots, buildings, etc. that prevent rainwater from soaking into the soil. The water increases in velocity causing more erosion; it warms causing potential heat stress for downstream trout; it picks up roadway contaminants; and the loss of vegetation removes a "sink" for dissolved nutrients - plant uptake.

Indicator: In biology, an organism, species, or community, that indicates the presence of certain environmental conditions.

Invasive Plant: A plant that moves in and takes over an ecosystem to the detriment of other species (often the result of environmental manipulation).

Landfill: A large, outdoor area for waste disposal; landfills where waste is exposed to the atmosphere are called open dumps which are currently against the law in the United States; in sanitary landfills, waste is layered and covered with soil.

Larvae: The earliest developmental stages of various animals that undergo metamorphosis, differing markedly in form and appearance from the adult.

Leaching: The process by which water filters down through the soil or some other material, often carrying with it dissolved nutrients, chemicals, or other pollutants.

Macroinvertebrate: An animal that lacks a backbone and is large enough to be seen with the naked eye.

Metalimnion: The middle or transitional zone between the well-mixed epilimnion and the colder hypolimnion layers in a lake. This layer contains an area in the water column where the temperature drops sharply.

Mirex: A persistent chlorinated compound that is resistant to biological and chemical degradation. It is converted to photomirex by sunlight with the loss of one chlorine atom per molecule. Both compounds are insoluble in water but dissolve in fatty tissue and adhere to sediment particles. Mirex was originally used as an insecticide and fire retardant and was produced in Niagara Falls, NY. It is no longer produced or used in New York.

Nonpoint Source Pollution: Pollution that cannot be traced to a specific point, because it comes from many individuals.

Nutrients: Substances which are necessary for the growth of all living things such as nitrogen, phosphorus, carbon, and potassium. Too many nutrients in water bodies can contribute to algae blooms.

Nymph: Young of an insect species that does not have a pupal stage in its development.

Oligotrophic: Very unproductive lakes low in nutrients and algae, usually very transparent with abundant hypolimnetic oxygen if stratified.

PCB's (Polychlorinated Biphenyls): Mixtures of chlorinated biphenyls with different degrees of chlorination. They are quite insoluble in water and adhere readily and strongly to sediments, soils, and fatty tissue. Because they are nonflammable and have useful heat exchange and electrical insulation properties, they have been used extensively in the electrical industry in capacitors and transformers. They were also used in lubricating and cutting oil formulations as well as in pesticide formulations. Adhesives, plastics, inks, paints, and sealants. The use of PCBs, except in closed systems, has been banned in the United States since the late 1970's.

Pesticide: Any chemical or biological agent that kills plant or animal pests; herbicides, insecticides, fungicides, rodenticides, etc., are all pesticides.

pH: A symbol for measuring the degree to which a solution is acidic or basic. It is based on a scale from 0 to 14. A pH of 7 is neutral, from 0 to 7 is acidic and from 7 to 14 is basic. Pure distilled water has a pH of 7.

Phosphorus: Key nutrient influencing plant growth in lakes. Soluble reactive phosphorus is the amount of phosphorus in solution that is available to plants. Total phosphorus includes the amount of phosphorus in solution (reactive) and in particulate form.

Photosynthesis: The process by which green plants convert carbon dioxide (CO2) dissolved in water to sugars and oxygen using sunlight for energy. Photosynthesis is essential in producing a lake's food base, and is an important source of oxygen for many lakes.

Phytoplankton: Microscopic floating plants, mainly algae, that live suspended in bodies of water and that drift about because they cannot move by themselves or because they are too small or too weak to swim effectively against a current.

Point source pollution: A type of pollution that can be traced to a specific source, usually an outfall or discharge pipe.

Pollution: A negative or unwanted change in character of air, water, or soil that can affect the health, survival, or activities of humans and other organisms in nature.

Polluted Runoff: See Runoff.

Riffle: A shallow, fast flowing rocky area of a stream. (A good place to collect aquatic macroinvertebrates.)

Riprap: Large rocks placed along the bank of a water body to prevent erosion.

Runoff: Water from rain, snowmelt, or irrigation that flows over the ground and into water features. It can collect pollutants from the air and land and carry them into the receiving waters.

Secchi Disk: A disk with a 4-6 inch radius that is divided into 4 equal quadrates of alternating black and white colors. It is lowered in to a section of shaded water until it can no longer be seen and then lifted back up until it can be seen once again. Averaging the two depths gives the clarity of the water.

Sediment: Insoluble material suspended in water that consists mainly of particles derived from rocks, soil, and organic materials; a major nonpoint source pollutant that other pollutants may attach to.

Septic System: An on-site wastewater treatment system that consists of two basic parts: an underground tank for sewage treatment, and a drainfield or leachfield for water dispersal into the soil.

Stormwater Discharge: Precipitation and snowmelt runoff from roadways, parking lots, roof drains that is collected in gutters and drains; a major source of nonpoint source pollution to water bodies.

Stormwater Runoff: Precipitation and snowmelt runoff from roadways, parking lots, roof drains that is collected in gutters and drains; a major source of nonpoint source pollution to water bodies.

Surface Water: Precipitation which does not soak into the ground or return to the atmosphere by evaporation or transpiration, and is stored in streams, lakes, wetlands, and reservoirs.

Tributary: A stream that feeds into a larger stream, river, or lake.

Water Cycle: The movement of water from the atmosphere to the earth and back to the atmosphere through precipitation, runoff, infiltration, percolation, storage, evaporation, and transpiration.

Watershed: All the land that drains to a specific stream, river, or lake.

Wetland: A landform (marshes, swamps, bogs, and fens) characterized by the presence of water, hydric soils, and hydorphytic vegetation. Often wetlands form the transition zones between upland and deep-water environments.

Zooplankton: Microscopic animals which move passively in aquatic ecosystems.