I k New Page 1

[MA149]Pages 146-174
(It may take a while to download but I think it is worthy - John A. Keslick, Jr.)  A word from the webmaster - Within this article the word nutrient is misused at times where the true meaning is essential elements.  See my dictionary at www.treedictionary.com and look up nutrient as well as essential element.  The reason for the latter is to reduce misunderstanding of terms to better understand the message.  John A. Keslick, Jr.


VI. IMPROVING THE GAME

Figure 59. -Solar power and wind are two of the most promising sources of clean energy.  We are just beginning to develop the techniques necessary to generate electricity with large windmills (center background) and to heat and cool buildings with solar energy (solar collector panels on and near buildings).  The employment of solar power for many other uses is being explored in research programs around the world.

Page 146

ABIDING BY THE RULES

Energy

The conservation of energy offers the greatest opportunity for playing the Game of the Environment well.  But, to be effective, conservation must involve each of us as individuals.  It will be necessary for every person to make a strong personal commitment to conservation-a commitment that may require rethinking and perhaps reshaping of our personal lifestyles.  Where appropriate, emphasis must be on the development of mass transit and the production of small cars; on the insulation of existing buildings and the construction of new ones in ways that conserve energy; and on the reorientation of agricultural and industrial processes that use less energy. 
    Along with these energy conservation practices we must embark on programs to develop alternate sources of clean energy.  Recent reports indicate that both wind and solar power (fig. 59) can produce much more of our energy needs than had previously been suggested.  While it is questionable whether nuclear fusion will ever be a usable source of energy, only massive research will disclose its feasibility.

Page 147

Figure 60. - While only conceptionalized in this illustration, strip mine reclamation (background hills) will be an integral step in the coal producing process.  As our technologies improve, we may be able to actually make the sites more productive than they were originally.

Page 148

    Our need for energy can only increase, even if we eliminate all wasteful practices.  And our need may outstrip any progress we may make in developing alternative sources.   Since strip mining for coal will continue to increase, we must ensure through reclamation practices (fig. 60) that the productivity of land is restored to as high a level as possible.  And since we will continue to drill for oil and build pipelines in increasingly fragile Arenas, it is important that we learn from the hard environmental lessons of the past bow to conduct these activities. 
    The absence of visible stack emissions in the picture illustrating the landscape of the future on page 144 indicates that the cities of the future that survive will be those that have "cleaned up." Emissions from industrial and power generating plants that burn fossil fuels will be reduced sharply as better ways to remove particulates and noxious materials are developed and as clean sources of energy, such as solar, wind, tidal, and hydroelectric power, become relatively more abundant.  In certain circumstances, heated water from nuclear plants could be beneficial to ecosystems.  With wise planning, "thermal enrichment" could be used to cultivate aquatic food species, to lengthen the existing seasons for fishing and recreation, and to heat buildings, including greenhouses and domestic water supplies.  But these potential benefits must be weighed against the potential hazards of locating nuclear plants near population centers.  In our future Arena, the quality of life will be an important component in the energy equation.

Page 149

Figure 61.- Using forests and agricultural lands for final water treatment not only purifies the water but also recharges water supplies and cycles nutrients.

Page 150

Material Cycling

Solid waste disposal systems -landfills, dumps, incinerators - also are conspicuously absent in the picture on page 144 .  In our city of the future (indeed, in some European cities today) waste disposal will at last be coupled with reclamation.  Nature's Rule that all essential materials must cycle within the system will become a way of life, for no other reason than necessity.  There is simply no recourse but to change to a system where the circular movement of materials essential for our needs will be patterned after that of nature. 
    In our city of the future, it is likely that domestic and industrial solid waste will be collected and transported to reclamation centers and separated into combustibles and into metals and glass for recycling.  The combustibles may be burned to power the system-or perhaps they may be degraded to produce methane (also used for power) and compost for city gardens and parks.  It is quite possible that the value of recovered materials will offset the costs of collection and processing. 
    Sewage disposal systems will probably be linked directly to natural eco- systems at least for tertiary phases of water treatment.  Studies have demonstrated the feasibility of using forests and agricultural lands as recycling systems, where nutrients are incorporated by the Producer Players before they can intrude into waterways (fig. 61), and where water can be returned to recharge city aquifers.  In the future, the forest disposal systems will be cropped periodically to remove "excess" nutrients and prevent the overloading of cycles. 
    The primary concern in recycling materials in the future is the enormous energy that will be required to drive these cycles.  The closing of the last mines of precious metals and industrial minerals will signal the end of our free ride.   Just as great expenditures of energy were required by nature to separate, concentrate, and store mineral reserves eons ago, so, too, will we require great amounts of energy to repeatedly complete each phase of the cycle.  But when all costs (including those-of energy and environment) are considered, recycling still uses less energy than is ,used exploiting virgin materials; recycling also causes less air and water pollution and generates less solid waste.  Recycling is one of the basic ecological Rules of the Game by which we must abide. 
    An abundant supply of energy will be critical if we are to prevent cycles from running amuck.  And this presents a paradox because anticipated great increases in the use of coal and shale oil, the most likely stopgap energy sources, will result in great intrusions and disruptions of the sulfur, nitrogen, and carbon cycles-cycles that already are overloaded.

Page 151

CAREFUL MANIPULATION OF ECOSYSTEMS

The picture illustrating the manipulation of ecosystems on page 106 shows many of our actions at their worst.  From the time we have had the ways and means to do so, we have ruined many of our ecosystems.  Ancient, advanced civilizations are no more; cities, cultural centers for centuries, lie forgotten in ruins; and once fertile lands are now deserts-primarily because we mistreated our agricultural Arenas. 
    Yet it must be reemphasized that these ecological disasters are not in- evitable.  There are many fine examples, especially in Europe, where land farmed for thousands of years is still highly fertile and productive; where exceedingly beautiful landscapes have been preserved because of the interactions of people and nature over centuries.  What we have often thought of as "natural" and pleasing is often the result of playing within the Rules of the Game of the Environment (fig. 62).

Figure 62. -Diversity of land-use patterns and preservation of prime agricultural lands - practices in accord with the Rules of the Game.

Click here for larger image

Page 152

This does not mean that we should not manipulate our environment - that we should stand aside and allow ecological succession to proceed unhindered.  But it does suggest that we should heed the lesson that successional processes demonstrate, namely, that nature abhors a biotic vacuum.  Following disturbance, the natural tendency is to reestablish a viable, solar subsidized, self- perpetuating ecosystem.  Among other things, this lesson demonstrates two points: (1) Succession usually results in ecological diversity and (2) energy is required to hold successional processes in check. 
    In keeping with the first point, and as we discussed earlier, a diverse crop system is usually a hedge against devastation by pests or climate, and a landscape with diverse vegetational and land-use patterns can be esthetically desirable.  The second point suggests that we must realize and accept the fact that great energy subsidies will be required to grow low-diversity crops to hold back succession.  (In nature, succession is held in check by energy subsidies such as fire, insect defoliation, wind, and flood.)  As supplies of fossil fuel wane, it will be imperative that top priority be given to using them for subsidizing ecosystems that produce food.

Page 153

Figure 63.-In the future, productive natural ecosystems such as this salt marsh and estuary will be protected as national assets.

Page 154

Of necessity, land-use policies must soon become alined with ecological principles.  It no longer will be possible for urban sprawl to gobble up more than a million acres of prime agricultural land each year as it does now.  Several European countries have led the way in preserving their agricultural land base; a number of our own States are considering legislation which would empower them to purchase agricultural land outright or to purchase the developmental rights.  It is hoped that enlightened societies will enact these necessary policies long before the energy crunch does it for them. 
    In our future Arena, the sea itself will no longer be regarded as our infinite dumping ground.  The global nature of the sea (as with the air of the biosphere) will demand international approaches to the monitoring and control of pollution, and to the exploration and the exploitation of the sea's minerals, energy reserves, and fisheries. 
    Productive natural ecosystems will be highly prized for their contributions to our well-being, and they will be protected against destruction.  The salt marsh and estuary "nurseries" of our natural fisheries will be recognized and treated as national assets (fig. 63).  Many states have enacted legislation to protect their coastal wetlands from large-scale, destructive activities. 
    Earthmanship will succeed only when the entire biosphere is treated as a single unit, when all actions, no matter how small, are in accord with the Rules of the Game.  As the dominant Players of the Game of the Environment, our ultimate challenge will be to change from a pioneer Grand Exploiter to an enlightened and benevolent Steward of our environment.  We have always had the capacity to do so.  We now have the necessary motivation to do so-survival.

---- ---- ---- ----

IN YOUR ENVIRONMENTAL ARENA

 List the ways in which your community could improve its Gamesmanship in living within the Rules. 
 How would your lifestyle have to change? 
 What actions would be required to improve the Game?  By whom? 
 In what ways would it be more costly to live in your improved community?  In what ways would it be less costly?

Page 155

The Forest Service has developed a package of materials to help you better understand environmental relationships.  The package, Investigating Your Environment, contains lesson plans and an approach for studying water, soil, animals, forest; and people-produced communities.  You may obtain a copy by writing to: U.S. Department of Agriculture, Forest Service, Office of Information, Environmental Education, Room 3235, P.O. Box 2417, Washington, D.C. 20013.

Page 156

GLOSSARY OF ENVIRONMENTAL TERMS

A.

ABIOTIC: Nonliving.
ABSORPTION: The process of taking inorganic salts, in solution, into root hairs from soil water by osmosis.  In pollution control, absorption is the dissolving of a soluble gas, present in an emission, in a liquid, from which it can be extracted.
ABYSSAL ZONE: The area of the bottom waters of the ocean depths. 
ACCLIMATION: The physiological and behavioral adjustments of an organism to changes in its immediate environment. 
ACID PRECIPITATION: Snow or rain with a pH value of less than 5.6. 
ACTINOMYCETES: Small filamentous forms of bacteria that have some of the morphological characteristics of fungi.  These organisms are important decomposers. 
ADAPTION:
A change in the structure or habit of an organism that enables it to better adjust to the environment. 
ADVANCED WASTE TREATMENT: Waste water treatment beyond the secondary or biological stage that includes removal of nutrients such as phosphorus and nitrogen, and a high percentage of suspended solids.  Advanced waste treatment, known as tertiary treatment, is the "polishing" stage of waste water treatment; it produces a high-quality effluent. 
AEROBIC: Refers to life or processes that can occur only in the presence of oxygen. 
AEROSOL:
A suspension of liquid or solid particles in the air. 
AGRICULTURAL POLLUTION: The liquid and solid wastes from all types of farming, including runoff from animal waste disposal areas and the land used for livestock and crop production; erosion and dust from plowing; animal manure and carcasses; and crop residues and debris. 
AIR MONITORING: See monitoring. 
AIR POLLUTION: The presence of contaminants in the air in concentrations that prevent the normal dispersion of substances by the air, and that interfere directly or indirectly with our health, safety, or comfort. 
AIR POLLUTION EPISODE: Abnormally high concentrations of air pollutants, usually due to low winds and temperature inversion, and accompanied by an increase in illness and death.  See inversion. 
AIR QUALITY CRITERIA: The levels of pollution and lengths of exposure at which adverse effects on health and welfare occur. 
AIR QUALITY STANDARDS:
As prescribed by law, the level of pollutants in the outside air that cannot be exceeded during a specified time in a specified geographical area. 
ALGA (Algae): Simple, one- to many-celled plants capable of carrying on photosynthesis.  
AMBIENT AIR
: Any unconfined portion of the atmosphere; the outside air. 
ANAEROBIC: Refers to life or processes that occur in the absence of oxygen.

Page 157

AQUACULTURE: The growing ("farming") of plants or animals in or under the seas, lakes, ponds, rivers, or other water bodies. 
AQUATIC PLANTS: Plants that grow in water; includes those that float on the surface, grow up from the bottom of the body of water, or grow under the surface of the water.  
AQUIFER:
An underground bed or stratum of earth, gravel, or porous stone that contains water. 
ASSIMILATION: Conversion or incorporation of absorbed nutrients into protoplasm.  Also refers to the ability of a body of water to purify itself of organic pollution. 
ATMOSPHERE: The gaseous envelope of air that surrounds the earth and is held to it by the force of gravity. 
ATTRITION: Wearing or grinding down by friction.  One of the three basic processes that contribute to air pollution; the others are vaporization and combustion. 
AUTOTROPHIC ORGANISMS (Autotrophs): Self-nourishing: denotes those organisms capable of constructing organic matter from inorganic substances.  See Producers.

B.

BACTERIA: Single-celled microorganisms that lack chlorophyll.  Some bacteria are capable of causing human, animal, or plant diseases; others are essential because they break down organic matter in the air and in the water.  With fungi, they comprise the decomposer level of food chains. 
BATHYAL ZONE: The open water zone in an ocean below the level where light penetrates.  
BENTHIC REGION:
The bottom of a body of water.  This region supports the benthos, a type of life that not only lives upon but also contributes to the character of the bottom.  
BENTHOS:
The plant and animal life whose habitat is the bottom of a sea, lake, or river.  
BIOCHEMICAL OXYGEN DEMAND (BOD):
A measure of the amount of oxygen consumed in the biological processes that break down organic matter in water.  Large amounts of organic waste use up large amounts of dissolved oxygen; thus the greater the degree of pollution, the greater the BOD. 
BIODEGRADABLE: The process of decomposing as a result of the action of microorganisms. 
BIOGEOCHEMICAL CYCLES: The mechanisms by which essential and non- essential materials move through the biosphere to be used over and over again. 
BIOLOGICAL CONTROL: A method of controlling pests by introduced or naturally occurring predatory organisms, sterilization, or the use of inhibiting hormones rather than by mechanical or chemical means. 
BIOLOGICAL MAGNIFICATION: Buildup in the concentration of substances in successively higher levels of the food chain.

Page 158

BIOLOGICAL OXIDATION: The process by which bacteria and other microorganisms feed on complex organic materials and decompose them.  Self-purification of waterways and activated sludge and trickling-filter waste water treatment processes depend on this principle. This process is also called biochemical oxidation. 
BIOMASS: The total weight (mass) of all living matter in a particular habitat or area.  
BIOME:
The complex of communities maintained by the climate of the region and characterized by a distinctive type of vegetation.  The biomes of North America include the tundra, the desert, the eastern deciduous forest, the prairie, the northern boreal forest, and the western coniferous forests. 
BIOSPHERE: The portion of the earth and its atmosphere capable of supporting life.  
BIOTA:
All species of plants and animals that occur within a certain area. 
BIOTIC: Living. 
BLOOM: A proliferation of living algae or other aquatic plants on the surface of lakes or ponds.  Blooms are frequently stimulated by phosphate enrichment.  BOD:  See biochemical oxygen demand. 
BOG: A wetland that is formed in a former glacial lake by the accumulation of' organic matter.  Peat often accumulates to a depth of 40 feet. 
BREEDER: A nuclear reactor that produces, from nonfissionable uranium-238, at least as much fissionable material (such as plutonium-239 or thorium) as is needed for the chain reaction, and usually more.

C.

CALORIE (GRAM CALORIE): The amount of energy required to raise the temperature of 1 gram (g) of water 1�C. 
CARBON DIOXIDE (CO
2): A colorless, odorless, nonpoisonous gas that is a normal part of the ambient air.  CO2 is a product of fossil fuel combustion; some researchers have theorized that an excess of CO2 raises atmospheric temperatures. 
CARBON MONOXIDE (CO): A colorless, odorless, highly toxic gas that is a normal byproduct of incomplete fossil fuel combustion.  CO, one of the major air pollutants, can be harmful in small quantities if breathed over a certain period of time. 
CARNIVORES: Organisms that eat animals. 
CARRYING CAPACITY: The maximum number of living things that can be supported indefinitely by a given ecosystem. 
CELLULOSE: A chemical substance that forms the walls of plant cells; the woody part of trees and plants.  Its formula is (C
6H10O5)n. 
CHILLING EFFECT: The lowering of the earth's temperature due to the increase of atmospheric particulates that inhibit penetration of the sun's energy. 
CLIMATE: The kind of weather a place has over a period of years, based on conditions of heat and cold, moisture and dryness, clearness and cloudiness, wind and calm.

Page 159

CHLORINATED HYDROCARBONS: A class of generally long-lasting, broad- spectrum insecticides of which the best known is DDT, first used for insect control during World War II.  Similar compounds include aldrin, dieldrin, heptachlor, chlordane, lindane, endrin, mirex, benzene hexachloride (BHC), and toxaphene.  The qualities of persistence and effectiveness against a variety of insect pests were long regarded as highly desirable in agriculture, public health, and home uses.  But research has revealed that these same qualities may represent a potential hazard by accumulating in the food chain and persisting in the environment.
CHRONIC:
Marked by long duration or frequent recurrence, as a disease.  
CLEARCUTTING:
Removing an entire stand of timber from a forest area.
CLIMAX COMMUNITY: A relatively stable community that appears to perpetuate itself in the absence of disturbance. 
COASTAL ZONE: Coastal waters and adjacent lands that exert a measurable influence on the uses of the sea and its ecology. 
COLIFORM INDEX: An index of the purity of water based on a count of its coliform bacteria. 
COLIFORM ORGANISM: Any of a number of organisms common to the intestinal tract of humans and animals, and whose presence in waste water is an indicator of pollution and of potentially dangerous contamination. 
COMBUSTION: Burning.  Technically, a rapid oxidation accompanied by the release of energy in the form of heat and light.  It is one of the three basic factors that contribute to air pollution; the others are attrition and vaporization. 
COMMUNITY: The group of populations occupying a particular habitat or area.  
COMPOST:
Relatively stable decomposed organic material. 
COMPOSTING: A controlled process of degrading organic matter by microorganisms. (1) Mechanical: a method in which the compost is continually and mechanically mixed and aerated. (2) Ventilated cell: compost is mixed and aerated by being dropped through a vertical series of ventilated cells. (3) Windrow: an open-air method in which compostable material is placed in windrows, piles, or ventilated bins or pits and is occasionally turned or mixed.  The process may be aerobic or anaerobic. 
CONDENSATION: The process whereby water is changed from a gas (water vapor) to a liquid. 
CONSUMERS: Organisms that live off others.  Usually they are classified as primary consumers (herbivores), secondary consumers (carnivores), and microconsumers (decomposers). 
COOLING TOWER: A device that removes excess heat from water used in industrial operations, usually in electric power generation. 
CULTURAL EUTROPHICATION: Acceleration by human action of the natural aging process of bodies of water. 
CYCLING: See Biogeochemical Cycling.

Page 160

D.

DDT: The first of the modern chlorinated hydrocarbon insecticides whose chemical name is 1, 1, 1-trichloro-2, 2-bis (p-chloriphenyl)-ethane.  It has a half- life of 15 years, and its residues can become concentrated in the fatty tissues of certain organisms, especially fish. Because of its persistence in the environment and its ability to accumulate and magnify in the food chain, EPA banned the registration and interstate sale of DDT for nearly all uses in the United States, effective December 31, 1972. 
DECOMPOSERS: Bacteria and fungi that chemically degrade (rot or decay) organic matter.
DECOMPOSITION
: Reduction of the net energy level and change in chemical composition of organic matter due to the actions of aerobic or anaerobic microorganisms. 
DEFOLIATION:
Removal of leaves from plants. 
DESALINIZATION: Removal of salt from seawater or brackish water.
DETERGENT: Synthetic washing agent that, like soap, lowers the surface tension of water, emulsifies oils, and holds dirt in suspension.  Environmentalists have criticized the use of detergents because most have large amounts of phosphorus-containing compounds that contribute to the eutrophication of waterways. 
DETRITUS: The particulate organic matter included in the decomposition of dead material.  
DETRITUS FOOD CHAIN:
The transfer of energy from one food (trophic) level to another by decomposers. 
DIATOMS: Any of numerous microscopic, unicellular aquatic algae that have hard shells composed mostly of silica. 
DIGESTION: The biochemical decomposition of organic matter.  The digestion of sewage sludge takes place in tanks where the sludge decomposes; this results in partial gasification, liquefaction, and mineralization of pollutants. 
DILUTION RATIO: The ratio of the volume of water of a stream to the volume of incoming waste.  The capacity of a stream to assimilate waste is partially dependent upon the dilution ratio. 
DISINFECTION: Effective killing by chemical or physical processes of all organisms capable of causing infectious disease.  Chlorination is the disinfection method commonly used in sewage treatment. 
DISSOLVED OXYGEN (DO): The oxygen dissolved in water or sewage.  Adequately dissolved oxygen is necessary for the survival of fish and other aquatic organisms and for the prevention of offensive odors.  Low concentrations of dissolved oxygen generally are caused by the discharge of excess organic solids that have high BOD-the result of inadequate waste treatment. 
DIVERSITY OF ORGANISMS: Biological complexity (the number of species) of an ecosystem.  In many instances, the ecosystem becomes more stable as diversity increases.

Page 161 

DREDGING: A method for deepening streams, swamps, or coastal waters by scraping and removing solids from the bottom.  The resulting mud is usually deposited in marshes in a process called filling.  Dredging and filling can disturb natural ecological cycles.  For example, dredging can destroy oyster beds and other aquatic life; filling can destroy the feeding and breeding grounds for many fish species. 
DUMP: A land site where solid waste is disposed of in a manner that usually does not protect the environment. 
DUST: Fine-grain particulate matter that is capable of being suspended in the air.  
DYSTROPHIC LAKES:
Lakes between eutrophic and swamp stages of aging.  Such lakes are shallow and have high humus content, high organic matter content, low nutrient availability, and high BOD.

E.

ECOLOGICAL IMPACT: The total effect of an environmental change, either natural or human-caused, on the ecology of the area. 
ECOLOGICAL SUCCESSION: The changes, over time, in the structure and function of an ecosystem. Primary succession occurs on sites where no previous vegetation existed (bare sand); secondary succession occurs on sites that supported vegetation previously (abandoned fields). 
ECOLOGY: The interrelationships of living things to one another and to their environment, or the study of these interrelationships. 
ECOSYSTEM: The interacting system of a biological community and its non- living environment; also, the place where these interactions occur. 
EFFLUENT: A discharge of pollutants into the environment, partially or completely treated or in their natural state; usually refers to discharges into water. 
EMISSION: Usually refers to discharges in air.  See effluent. 
EMISSION STANDARD: The maximum legal amount of a pollutant that can be discharged from a single mobile or stationary source. 
ENERGY: The capacity to do work. 
ENERGY FLOW: The one-way passage (transfer) of energy through an ecosystem.  
ENERGY PYRAMID:
Passage of energy from one trophic level to another.  Because much energy is lost as heat (80 to 90 percent) in each transfer, the shape of the energy pyramid is always "right side up." 
ENRICHMENT: The addition of nitrogen, phosphorus, and carbon compounds or other nutrients into a lake or other waterway that greatly increases the growth potential for-algae and other aquatic plants.  Most frequently, enrichment results from the inflow. of sewage effluent or from runoff from farmlands. 
ENVIRONMENT: The sum of all external conditions and influences that affect the development and, ultimately, the survival of an organism. 
EPILIMNION: The warm, less dense top layer in a stratified lake. 
EROSION: The wearing away of the land surface by wind or water.  Erosion

Page 162

occurs naturally from weather or runoff, but it is often intensified by our land- clearing practices. 
ESTUARY: An area where freshwater meets saltwater; for example, a bay, mouth of a river, salt marsh, or lagoon.  Estuaries are delicate ecosystems; they serve as nursery, spawning, and feeding grounds for a large group of marine life, and they provide shelter and food for birds and wildlife. 
EUTROPHICATION: The normally slow aging process by which a lake evolves into a bog or marsh and ultimately assumes a completely terrestrial state and disappears.  During eutrophication, the lake becomes so rich in nutritive compounds-especially phosphorus-that algae and other microscopic plant life become superabundant, thereby "choking" the lake and causing it to dry up.  Eutrophication may be accelerated by many human activities. EUTROPHIC LAKE: A shallow lake that is choked by weeds at the edge and very rich in nutrients.  The water is characterized by large amounts of algae, low water transparency, low dissolved oxygen, and high BOD. 
EUTROPHIC ZONE: The surface layer of water bodies where light penetrates; the zone where photosynthesis occurs. 
EVAPORATION: The process whereby water is changed from a liquid to a gaseous state (water vapor).

F.

FALLOUT: The radioactive particles or dust that fall to the earth after an atomic explosion. Fallout may be assumed always to be dangerously radioactive. 
FEEDLOT: A confined space where large numbers of livestock are fattened for slaughter.  Although an economical method of fattening beef, a feedlot concentrates a large amount of animal wastes in a small area.  Excrement cannot be handled by the soil on a feedlot as it can on an open range where cattle are scattered.  Runoff from feedlots also contributes excessive quantities of nitrogen, phosphorus, and potassium to nearby waterways, thus contributing to eutrophication. 
FILLING: The process of depositing dirt and mud in marshy areas, often to create more land for real estate development.  Filling can disturb natural ecological cycles.  See Dredging.
FILTRATION: In waste water treatment, the mechanical process that removes particulate matter by separating water from solid material, usually by passing it through sand. 
FINITE RESOURCES (Nonrenewable): Resources such as minerals and fossil fuels that exist as fixed, depletable supplies. 
FIRST LAW OF THERMODYNAMICS: The law that states that while energy can be transformed from one type to another, it can neither be created nor destroyed. 
FISSION: The process by which neutrons and energy are released when the nucleus of a heavy element (uranium-235, plutonium-239) splits into nuclei (usually two) of lighter elements.

Page 163

FIXATION: The process of making stable by decreasing or destroying volatility, fluidity, etc.
FLOOD PLAIN:
A lowland fringing a watercourse.  It serves a valuable function by containing large volumes of water in times of flood.  Development on flood plains, therefore, is considered unwise. 
FOOD CHAIN: The transfer of food energy from organisms in one trophic level to those in another.  There are two pathways or "circuits": the grazing food chain and the detritus food chain. 
FOOD WEB:
The complex and interlocking series of food chains. 
FOREST: A large area of land covered with trees. 
FOSSIL FUELS: Coal, oil, and natural gas; called fossil fuels because they are derived from the remains of ancient plant and animal life. 
FUNGI: Small, often microscopic plants without chlorophyll.  Some fungi infect and cause disease in plants or animals; other fungi are useful in stabilizing sewage or in breaking down wastes for compost. 
FUNGICIDE: A pesticide chemical that kills fungi or prevents them from causing diseases, usually on plants of economic importance.  See Pesticide. 
FUSION:
The process by which energy is released when nuclei of light elements combine to form the nucleus of a heavier element.

G.

GAME FISH: Those species of fish sought by sports fishermen; for example, salmon, trout, black bass, and striped bass.  Game fish are usually more sensitive to environmental changes and the degradation of water quality than "rough fish." 
GASEOUS CYCLE: Biogeochemical cycles in which the primary reservoir is the atmosphere. 
GASIFICATION: The processing of coal to produce synthetic natural gas (SNG).
GENERATOR:
A device that converts mechanical energy into electrical energy.
GEOTHERMAL ENERGY:
Energy derived from the heat of the earth's interior.
GRAZING FOOD CHAIN:
Transfer of food energy from plants to animals, excluding the actions of decomposers. 
GREEN BELT: An area where building is restricted; it often serves as a buffer between sources of pollution and concentrations of population. 
GREENHOUSE EFFECT: The heating effect of the atmosphere upon the earth.  Light waves from the sun pass through the air and are absorbed by the earth.  The earth then reradiated this energy as heat waves that are absorbed by the air, specifically by carbon dioxide.  The air thus behaves like glass in a greenhouse, allowing the passage of light but not heat.  Many scientists believe that an increase in the atmospheric concentration of CO
2 can eventually cause an increase in the earth's surface temperature. 
GROUNDWATER: The supply of freshwater under the earth's surface in an aquifer or soil that forms the natural reservoir for use by humans.

Page 164

GROUNDWATER RUNOFF: Groundwater that is discharged into a stream channel as spring or seepage water.

H.

HABITAT: The sum of environmental conditions of a specific place that is occupied by an organism, a population, or a community. 
HALF-LIFE: The time it takes certain materials such as persistent pesticides or radioactive isotopes to lose half their strength.  For example, the half-life of DDT is 15 years; the half-life of radium is 1,580 years. 
HAZARDOUS AIR POLLUTANT:
According to law, a pollutant to which no ambient air quality standard is applicable, and that may cause or contribute to an increase in death or in serious illness.  Asbestos, beryllium, and mercury have been declared hazardous air pollutants. 
HEAT ISLAND EFFECT: An adverse atmospheric condition that is peculiar to cities.  Tall buildings, heat from pavements, and concentrations of pollutants create a "dome" of haze that prevents rising hot air from being cooled at its normal rate.  A self-contained circulation system is put into motion that can be broken by relatively strong winds.  If such winds are absent, the heat island can trap high concentrations of pollutants and cause a serious health hazard. 
HEAVY METALS: Metallic elements with high molecular weights; in low concentrations, generally toxic to plant and animal life.  Such metals are often residual in the environment, and they are biologically accumulative.  Examples include mercury, chromium, cadmium, arsenic, and lead. 
HERBICIDE: A pesticide chemical used to destroy or control the growth of weeds, brush, and other undesirable plants.  See Pesticide. 
HERBIVORE: An organism that feeds on vegetation. 
HETEROTROPHIC ORGANISM (Heterotrophs): Organism that depends on organic matter for food.  Includes all animals and some plants. 
HUMUS: Decomposed material that is a highly complex mixture of organic and inorganic substances. 
HYDROCARBONS:
A vast family of compounds containing carbon and hydrogen, found especially in fossil fuels.  Some hydrocarbons are major air pollutants, some may be carcinogenic, others contribute to photochemical smog. 
HYDROELECTRIC POWER: Electricity generated by turbines that operate by water flow. 
HYDROGEN SULFIDE (H
2S): A gas, made up of hydrogen and sulfur, that has an odor characteristic of rotten eggs.  It is emitted in the natural decomposition of organic matter, and it is the natural accompaniment of advanced stages of eutrophication.  H2S is also a byproduct of refining activity and the combustion of oil during power plant operations.  In heavy concentrations, it can cause illness. 
HYDROSPHERE: The water portion of the earth, including water vapor.  
HYPOLIMNION:
The lower depths of a lake below the thermocline.

Page 165 

I.

INCINERATION: A controlled process by which solid, liquid, or gaseous combustible wastes are burned and changed into gases; the residue contains little or no combustible material. 
INFILTRATION: The flow of a fluid into a substance through pores or small openings; commonly used in hydrology to denote the flow of water into soil material. 
INFRARED: The part of the invisible spectrum whose wavelengths are longer than those of the red part of the visible spectrum.  Most of the heat from sunlight is from infrared rays.
INGESTION: The act of taking food and water, etc., into the body for digestion.
INTEGRATED PEST CONTROL:
A system of managing pests by biological, cultural, and chemical means. 
INTERTIDAL ZONE: The zone along the shore between high and low tides (littoral zone).  
INVERSION:
An atmospheric condition where a layer of cool air is trapped by an upper layer of warm air.  Inversions spread polluted air horizontally rather than vertically so that contaminating substances cannot be widely dispersed.  An inversion of several days can cause an air pollution "episode." 
ISOTOPE: A variation of an element having the same atomic number as the element itself, but having a different atomic weight because of a different number of neutrons.  Different isotopes of the same element have different radioactive behavior.

K.-L.

KILOCALORIE: Unit of energy equal to 1,000 calories. 
LAGOON: In waste water treatment, a shallow pond, usually not natural, where sunlight, bacterial action, and oxygen interact to restore waste water to a reasonable state of purity. 
LAKE:
A large body of water entirely or nearly surrounded by land.  Lakes differ from ponds chiefly in size, but this carries with it profound changes in all the principal factors of environment -light, temperature, and dissolved gases- with their effects upon nutrition. 
LANDFILL:
A place where solid waste is dumped.  See Sanitary Landfilling. 
LEACHING: The process by which soluble materials in soil such as nutrients, pesticide chemicals, and contaminants are washed into a lower layer of soil, or are dissolved and carried away by water. 
LEAD: A heavy metal that may be hazardous to health if breathed or ingested.
LIFE CYCLE: The phases, changes, or stages through which an organism passes during its lifetime. 
LIGNIN: The organic substance that holds together the individual fibers of wood.

Page 166

LIMITING FACTOR: Factors such as temperature, light, water, and nutrients that limit the ability of an organism to grow and survive. 
LIMNITIC ZONE: In lakes, the open-water region that supports plankton and fish as the principal Producers and Consumers. 
LIMNOLOGY: The study of the physical, chemical, meteorological, and biological aspects of fresh water. 
LITTORAL ZONE: The area on or near the shore of a water body.  In the ocean, this area is called the intertidal zone.

M.

MACROCONSUMERS: Organisms, chiefly animals, which ingest other organisms or particulate organic matter. 
MACRONUTRIENTS: Chemicals required by organisms in relatively large quantities.  Carbon, oxygen, hydrogen, and nitrogen are examples. 
MARSH: A low-lying tract of soft wetland that provides an important ecosystem for a variety of plant and animal life, but that often is destroyed by dredging and filling.  Trees and shrubs are absent. 
MEGALOPOLIS: A large continuous urban belt formed by a number of cities that adjoin each other. 
MERCURY: A heavy metal, highly toxic if breathed or ingested.  Mercury is residual in the environment, and it accumulates in aquatic organisms, especially fish and shellfish.  Chronic exposure to airborne mercury can seriously affect the central nervous system. 
METHANE: Colorless, nonpoisonous, and flammable gaseous hydrocarbon.  Methane (CH
4) is emitted by marshes and by dumps undergoing anaerobic decomposition.
MICROCONSUMERS:
See Decomposers. 
MICRONUTRIENTS: Chemicals required by organisms in small quantities.  Included in this group are copper, nickel, and magnesium. 
MICROORGANISM (Microbes): Microscopic organisms including bacteria, yeasts, fungi; some algae, and protozoans. 
MONITORING: Periodic or continual determination of the amount of pollutants or radioactive contamination in the environment. 
MONOCULTURE: The growing of a single species to the exclusion of others on a large area of land. 
MULCH: A layer of wood chips, dry leaves, straw, hay, plastic strips, or other material placed on the soil around plants to retain moisture, to prevent weeds from growing, and to enrich soil. 
MUTATION: The process of change in the genetic material that determines the characteristics of a species.  When caused by chemicals, mutations are usually deleterious.

Page 167

N.

NATURAL GAS: A fuel gas that occurs naturally in certain geologic formations,  Natural gas is usually a combustible mixture of methane and hydrocarbons. 
NATURAL SELECTION: The process by which the organisms best adapted to their environment survive and those less well adapted are eliminated. 
NICHE: The ecological role played by organisms.  Also refers to specific places where individual organisms can live (spatial niche). 
NITRIC OXIDE (NO): A gas formed in great part from atmospheric nitrogen and oxygen when combustion takes place under high temperature and high pressure, as in internal combustion engines.  NO itself is not a pollutant; however, in the ambient air, it converts to nitrogen dioxide, a major contributor to photochemical smog. 
NITROGEN DIOXIDE (NO
2): A compound produced by the oxidation of nitric oxide in the atmosphere; a major contributor to photochemical smog. 
NITROGEN FIXATION: The process by which some bacteria arid algae convert atmospheric nitrogen into nitrates. 
NITROGENOUS WASTE: Waste of animal or plant origin that contains a significant concentration of nitrogen. 
NO: A notation meaning oxides of nitrogen, See Nitric Oxide. 
NONRENEWABLE RESOURCES: See Finite Resources. 
NUCLEAR POWER PLANT: Any device, machine, or assembly that converts nuclear energy into some form of useful power, such as mechanical or electrical power.  In a nuclear electric power plant, heat produced by a reactor is generally used to make steam to drive a turbine that, in turn, drives an electric generator. 
NUCLIDE: An atomic species in which all atoms have the same atomic number and mass number; an individual atom in such a species. 
NUTRIENTS:  Elements or compounds essential as raw materials (building blocks) for the growth and development of an organism; for example, carbon, oxygen, nitrogen, and phosphorus.  See Macronutrient and Micronutrient.

[Note from web master. Please see essential elements and nutrients at www.treedictionary.com for some additional thoughts on the topic. John A. Keslick, Jr.]

O.

OIL SHALE: Fine-grain shale rock impregnated with natural hydrocarbons.
OIL SPILL: The discharge of oil into oceans, bays, or inland waterways.  Methods of controlling oil spills include chemical-dispersion, combustion, mechanical containment, and absorption.
OLIGOTROPHIC LAKE: A deep lake that has a low supply of nutrients and thus contains little organic matter.  Such lakes are characterized by high water transparency and high dissolved oxygen.
OMNIVORES: Organisms that eat animals and plants.
ORGANIC:
Referring to or derived from living organisms.  In chemistry, any compound containing carbon.
ORGANISM:
Any living human, plant, or animal.

Page 168

ORGANOPHOSPHATES: A group of pesticide chemicals, containing phosphorus, that are used to control insects.  These compounds are short-lived and, therefore, do not usually contaminate the environment.  However, organophosphates such as parathion are extremely toxic when initially applied and exposure to them can interfere with the normal processes of the nervous system, causing convulsions and eventually death.  Other organophosphates such as malathion are low in toxicity and relatively safe for humans and animals; malathion is a common ingredient in household insecticides.  
OUTFALL:
The mouth of a sewer, drain, or conduit where effluent is discharged into a body of water. 
OXIDANT:
Any oxygen-containing substance that reacts chemically in the air to produce new substances.  Oxidants are primary components of photochemical smog. 
OXIDATION: The combining of oxygen with another element to form one or more new substances.  Burning is one kind of oxidation.  Organic matter is oxidized by the action of aerobic bacteria.
OXIDATION POND: A constructed lake or pond in which organic wastes are reduced by bacterial action.  Oxygen often is injected into the pond to speed the process. 
OZONE (O
3): A pungent, colorless, toxic gas.  Ozone is a component of photo- chemical smog and is considered a major air pollutant. 
OZONE LAYER: A layer of ozone in the high atmosphere that protects life on earth by filtering out lethal ultraviolet radiation.

P.

PAN: Peroxyacetyl nitrate, a pollutant created by the action of sunlight on hydrocarbons and nitrogen oxides in the air.  PAN's are an integral part of photo- chemical smog. 
PARTICULATE: Finely divided solid or liquid particle in the air or in an emission.  Particulates include dust, smoke, fumes, mist, spray, and fog. 
PATHOGEN: Any organism that incites disease. PATHOGENIC: Inciting or capable of inciting disease. 
PCB's: Polychlorinated biphenyls, a group of organic compounds used in the manufacture of plastics.  In the environment, PCB's have many of the same characteristics as DDT and, therefore, may be confused with that pesticide.  PCB's are highly toxic to aquatic life, they persist in the environment for long periods of time, and they are biologically accumulative. 
PERCOLATION: Downward flow or infiltration of water through the pores or spaces of rock or soil. 
PEST: Harmful or noxious insects, microorganisms, weeds, or animals. 
PESTICIDE: An agent used to control pests.  This can be an insecticide for use against harmful insects; a herbicide for weed control; a fungicide for control of plant diseases; a rodenticide for killing rats and mice; a germicide used in disinfectants; an algaecide, or a slimicide.  Some pesticides can contaminate water, air,

Page 169

or soil, and can accumulate in humans, animals, and the environment if misused.  Some of these chemicals also interfere with the reproductive processes of predatory birds and possibly other animals. 
pH: A measure of the acidity or alkalinity of a material, liquid, or solid. pH is represented on a scale of 0 to 14; 7 represents a neutral state; 0 represents the most acid., and 14, the most alkaline. 
PHENOLS: A group of organic compounds that in very low concentrations produce a foul taste or odor in water.  In higher concentrations, they are toxic to aquatic life.  Phenols are by products of petroleum refining; tanning; and textile, dye, and resin manufacturing processes. 
PHOSPHORUS:
An element that; while essential to life contributes to the eutrophication of lakes and other bodies of water. 
PHOTOCHEMICAL OXIDANTS: Secondary pollutants formed by the action of sunlight on the oxides of nitrogen and hydrocarbons in the air; they are the primary contributors to photochemical smog. 
PHOTOCHEMICAL SMOG:
Air pollution associated with oxidants rather than with sulfur oxides or particulates; smog causes necrosis,. chlorosis, and growth alteration in plants, and is an eye and respiratory irritant in humans. 
PHOTOSYNTHESIS: The process by which chlorophyll-bearing (green) plants combine carbon dioxide and water in the presence of light energy to form sugars; it is the conversion of light energy to potential chemical energy of food. Oxygen is released in the process. 
PHYSIOGRAPHY:
Physical geography.
PHYTOPLANKTON:
The plant portion of plankton. 
PLANKTON:
The often microscopic floating or weakly swimming plant and animal life in a body of water. 
POLLUTANT:
Any introduced gas, liquid, or solid that makes a resource unfit for a specific purpose. 
POLLUTION:
The presence of matter or energy whose nature, location, or quantity produces undesirable environmental effects.
POND: A body of still water smaller than a lake. 
POTABLE WATER:
Water suitable for drinking or cooking.
PRECIPITATION:
Water from the atmosphere that falls to the ground as rain, snow, sleet, or hail. 
PREDATOR:
Organisms that live by preying on other organisms.  Predators are at or near the tops of food chains.
PREY:
Organisms that serve as food for predators. 
PRIMARY TREATMENT:
The first stage in waste water treatment in which nearly all floating or settleable solids are mechanically removed by screening and sedimentation.
PRODUCERS:
Green plants that synthesize their own Organic Compounds from Inorganic Substances.  See Autotrophs.
PROTOPLASM: The complex living matter of organisms.

Page 170

R.

RADIATION: The emission of fast atomic particles or rays by. the nucleus of an atom.  Some elements are naturally radioactive; others become radioactive after bombardment with neutrons or other particles.  The three major forms of radiation are alpha, beta, and gamma. 
RADIOECOLOGY:
The study of the effects of radiation on plants and animals in natural communities. 
RADIOISOTOPE:
. Radioactive isotope whose nuclei emit radiation spontaneously.  Radioisotopes such as cobalt-60 are used in the treatment of disease:
RADIONUCLIDE: A radioactive nuclide. 
RECYCLING: The process by which waste materials are transformed into new products in such a way that the original products may lose their identity. 
RED TIDE: Seawater colored red or orange by a proliferation or bloom of a certain type of plankton; this bloom often causes massive, fish kills.  Though natural phenomena, blooms are believed to be stimulated by phosphorus and other nutrients discharged into waterways by humans. 
REFUSE RECLAMATION: The process of converting solid waste into commercial products.  For example, the composting of organic solid waste yields a salable soil conditioner. 
RESOURCE RECOVERY: The process of obtaining materials or energy, particularly from solid waste. 
RESPIRATION:
Aerobic oxidation of food or organic substances by organisms.  Respiration releases usable energy, carbon dioxide, and water. 
RIVER BASIN:
The total area drained by a river and its tributaries. 
RUNOFF:
The portion of rainfall, melted snow, or irrigation water that flows . across the ground (overland flow) and eventually is returned to streams.  Runoff can pick up pollutants from the air or on the land and carry them to bodies of water.

S.

SALINITY: The degree of salt in water. 
SANITARY LAND FILLING: A method of solid waste disposal on land that protects the environment; waste is spread in thin layers, compacted to the smallest practical volume, and covered with soil. 
SAPROTROPHIC ORGANISMS (Saprotrophs): Organisms that obtain food by absorbing the products of decomposition; they live off dead organisms. 
SCRUBBER: An air pollution control device that uses a liquid spray to remove pollutants from a gas stream, as for example in a smoke stack, by absorption or chemical reaction.  Scrubbers also lower the temperature of the emission. 
SECOND LAW OF THERMODYNAMICS: The law that states that energy is degraded to less useful forms (heat) as it flows through an ecosystem. 
SECONDARY TREATMENT: Waste water treatment beyond the primary stage in which bacteria consume the organic parts of the wastes. This biochemical

Page 171

action uses trickling filters or activated sludge. Effective secondary treatment removes virtually all floating and settleable solids, and about 90 percent of both BODs and suspended solids. Disinfection by chlorination usually is the final stage of the secondary process. 
SEDIMENT: Soil particles (sand, silt, clay, and minerals) washed from land into water systems as a consequence of natural or human activities. 
SEDIMENTATION: In waste water treatment, the settling out of solids by gravity. 
SEEPAGE: Water that flows through the soil. 
SELECTIVE HERBICIDE: A pesticide for killing only certain types of plants, especially broad-leafed weeds, but not other plants such as farm crops or lawn grasses. 
SILT: Very fine particles of earth, sand, clay, etc.  Often silt is carried by moving water and deposited as a sediment. SILTATION: The formation or deposition of silt.
SMELTING: The process of melting ore to extract metals or impure metal to refine it. |
SNG: See Synthetic natural gas. 
SOLAR RADIATION: The radiant energy of the sun. 
SOLID WASTE: Useless, unwanted, or discarded material with insufficient liquid content to be free flowing. (1) Agricultural: solid waste from raising and slaughtering animals and processing animal products, and orchard and field crops. (2) Commercial: waste from stores, offices, and other activities that do not actually turn out a product. (3) Industrial: waste from industrial processes and manufacturing. (4) Institutional: waste from institutions such as educational, health care, and research facilities. (5) Municipal: residential and commercial solid waste generated within a community. (6) Pesticide: residue from the manufacturing, handling, and use of chemicals designed to kill plant and animal pests. (7) Residential: waste that usually originates in a residential environment; sometimes called domestic solid waste. See Waste. 
SOLID WASTE DISPOSAL:
The ultimate disposition of refuse that cannot be salvaged or recycled. 
SPOIL:
Dirt or rock that has been removed from its original location; specifically, materials that have been dredged from the bottom of waterways. 
STABILITY: The ability of an ecosystem (the landscape, numbers of species, populations) to tolerate changes in the environment.
STABLE AIR:
An air mass that remains in the same position rather than moving horizontally or vertically.  Stable air does not disperse pollutants, and it can lead to high concentrations of air pollutants. 
STAGNATION:
Lack of wind in an air mass or lack of motion in water; both tend to trap and concentrate pollutants.
STRATIFICATION:
Separation into layers. 
STRIP MINING:
The process by which rock and topsoil strata overlying ore or fuel deposits are scraped away by mechanical equipment; also known as surface mining.

Page 172

SUCCESSION: See Ecological Succession. 
SULFUR DIOXIDE (SO
2): A heavy, pungent, colorless gas formed primarily by the combustion of fossil fuels.  SO2 damages the respiratory tract as well as vegetation and materials; it is considered a major air pollutant. 
SURVEILLANCE SYSTEM: A monitoring system to determine environmental quality.  Surveillance systems can be established to monitor progress in meeting environmental standards, and to identify potential episodes of high pollutant concentrations in time to take preventive action. 
SWAMP:
A marsh that contains wetland trees and shrubs. SYNERGISM: The cooperation of separate substances so that the total effect is greater than the sum of the effects of the substances acting independently. 
SYNTHETIC NATURAL GAS: (SNG)
A gas produced from coal by the process of gasification.  While SNG eliminates the high sulfur oxide and particulate air pollution problems associated with coal, it is relatively inefficient because about 25 percent of the coal's energy is lost in the conversion process.

T.

TERRESTRIAL: Of the land, not the water.
TERTIARY TREATMENT:
Waste water treatment beyond the secondary or biological stage; includes the removal of nutrients such as phosphorus and nitrogen, and a high percentage of suspended solids.  Tertiary treatment, also known as advanced waste treatment, produces a high-quality effluent.
THERMAL INVERSION: See Inversion. 
THERMAL POLLUTION: Degradation of water quality by the introduction of heated effluent; it is primarily the result of the discharge of cooling waters from industrial processes, particularly from electrical power generation.  Even small deviations from normal water temperatures can affect aquatic life.  Thermal pollution usually can be controlled by cooling towers.
THRESHOLD DOSE:
The minimum dose of a substance that is necessary to produce a measurable physiological or psychological effect.
TOLERANCE:
The relative capacity of an organism to endure an unfavorable environmental factor; the amount of a chemical on any food considered safe for consumption by humans or other animals. 
TOXICANT:
A substance that kills or injures an organism or that alters its environment through a chemical or physical action. Examples are cyanides, phenols, pesticides, and heavy metals. Toxicants are used especially for insect control.
TOXICITY: The quality of or degree to which a substance is poisonous or harmful to plant or animal life.
TRANSPIRATION: Evaporation of water from the leaves of plants.
TROPHIC LEVEL (Food level): The level at which food energy is transferred from one organism to another.
TROPOSPHERE:
The layer of the atmosphere extending 7 to 10 miles above

Page 173

the earth.  Vital to life on earth, the troposphere contains clouds and moisture that reach earth as rain or snow.

U.

UPWELLING REGION: The area adjacent to a continent where nutrient-rich bottom waters are brought to the surface where they can be used by organisms at the bottoms of food chains.
ULTRAVIOLET:
The invisible part of range of the spectrum just beyond the violet.  The visible spectrum from violet to red comprises only a small part of the whole range of wavelengths radiated by a source such as the sun. The spectrum goes on into the ultraviolet in one direction and into the infrared in the other.

V.

VAPOR: The gaseous phase of substances that usually are liquid or solid at atmospheric temperature and pressure; for example, steam and phenolic compounds.
VAPORIZATION:
The change of a substance from the liquid to the gaseous state.  One of three basic factors that contribute to air pollution; the others are attrition and combustion.
VOLCANISM:
The phenomena associated with volcanoes and volcanic activity.

W.

WASTE: ( 1) Bulky waste: an item whose large size precludes or complicates handling by normal collecting, processing, or disposal methods. (2) Construction and demolition waste: building materials and rubble from construction, remodeling, repair, and demolition operations. (3) Hazardous waste: waste that requires special handling to avoid illness or injury to persons or damage to property. (4) Special waste: waste that requires extraordinary management. (5) Wood pulp waste: wood or paper fiber residue from manufacturing processes. (6) Yard waste: plant clippings, pruning, and other discarded material from yards and gardens; also known as yard rubbish.  See solid waste.
WATER POLLUTION:
The addition of sewage, industrial waste, or other harmful or objectionable material to water in sufficient quantities to measurably degrade water quality.
WATERSHED:
The area drained by a stream.
WATER TABLE: The upper level of groundwater.
WETLAND: An area that is regularly wet or flooded, and where the water table stands at or above the land surface for at least part of the year.

Z.

ZOOPLANKTON: Planktonic animals that supply food for fish.

Page 174

*U.S. GOVERNMENT PRINTING OFFICE: 1979-0-300-842