Science Olympiad 2019: Water Quality


Without oxygen


Animals that live inside the sediment


Organisms that are affixed to the surface of the sediment

Mobile Epibenthos

Organisms that move around on the surface of the sediment


A group of individuals of the same species living in a given place


Comprised of populations of different species that live together


Encompasses the community and its abiotic environment


The places where organisms make their homes within the estuarine ecosystem

Habitat (Estuarine)

Tens of thousands of birds, mammals, fish, and other wildlife depend on estuaries

Nursery (Estuarine)

Many marine organisms, most commercially valuable fish species included, depend on estuaries at some point during their development.

Productivity (Estuarine)

A healthy, untended estuary produces from four
to ten times the weight of organic matter produced by a cultivated corn field the same size.

Water Filtration (Estuarine)

Water draining off the uplands carries a
load of sediments and nutrients. As the water flows through salt marsh peat and the dense mesh of marsh grass blades, much of the sediment and nutrient load is filtered out. This filtration process creates cleaner

Flood Control (Estuarine

Porous, resilient salt marsh soils and grasses
absorb floodwaters and dissipate storm surges. Salt marsh dominated estuaries provide natural buffers between the land and the ocean. They
protect upland organisms as well as billions of dollars of human real

Types of Estuaries

Coastal Plain Estuaries
Tectonic Estuaries
Bar-built Estuaries

Coastal Plain Estuaries

Formed as rising sea level invaded existing river valleys


Steepwalled valleys created by glaciers

Tectonic Estuaries

Formed when geologic faulting or folding resulted in a depression

Bar-built Estuaries

Separated from the ocean by barrier beaches lying
parallel to the coastline

Abiotic Factors


Light (Abiotic Factors)

Plants use energy in sunlight to convert water and carbon dioxide into carbohydrates and oxygen. This is accomplished through a series of chemical reactions called photosynthesis.

Oxygen (Abiotic Factors)

Used in respiration. Respiration releases
stored chemical energy to power an organism's life processes. An absence of oxygen severely restricts the amount of life that can be


Releases stored chemical energy to power an organism's life processes

Water (Abiotic Factors)

Without water, no organism can remain biologically active. In fact, all living organisms are comprised of 50 to 99 percent water.

Nutrients (Abiotic Factors)

Although sunlight is the fuel for food production, and water and carbon dioxide are the raw materials, plants cannot survive on these alone. Other substances, called nutrients, are necessary for the proper function of a living organism. Major nutrients, i

Temperature (Abiotic Factors)

Temperature is one of the best-understood abiotic
factors affecting the distribution and abundance of organisms. Temperature has a large impact on plants and animals because it influences their metabolic rates and affects rates of growth and

Salinity (Abiotic Factors)

Pure water contains only oxygen and hydrogen, but in the natural world, solid substances such as salt are often dissolved in water. In an estuary, the salt content of water fluctuates continuously
over the tidal cycle. It decreases drastically in the uppe

Space (Abiotic Factors)

A precious resource exploited by living things. The
need for space is most pronounced for organisms that need a substrate, or base, on which to live. Many animals require a certain amount and
type of space to meet their needs, other than simple physical a



Biotic Factors

Interactions among living things that affect the survival of species

List of Biotic Factors


Competition (Biotic Factors)

Occurs between organisms using a
resource that is in finite supply. Can occur between members of different species or the same species. They may compete for
food, space, light, nutrients, water, or even pollinators. Plays an important role in shaping comm

Predation (Biotic Factors)

Killing and/or consumption of one
organism by another. Herbivores eat plants, seeds, and/or fruits. Carnivores eat animals. Omnivores eat both plants and animals. Predation is a major selective force in animal evolution. Individuals are more likely to rep

Parasitism (Biotic Factors)

Similar to predation in that one species
benefits from the relationship and the other is harmed. Differs from predation, however, because parasitism is generally not fatal to the adversely affected organism.

Commensalism (Biotic Factors)

Commensal relationships occur when one
organism benefits and the other is neither helped nor harmed

Mutualism (Biotic Factors)

Occurs when both organisms gain from the relationship


Progressive changes in the composition of a community

Anthropogenic Disturbances

Human created disturbance

Ecological Responses

Happen during the lifetime of a single organism

Evolutionary Adaptation

Happens over the course of multiple individuals' lifetimes and causes changes to occur in a
species' genetic makeup

Natural Selection

Process in which a species' genetic makeup changes.


Creation of a new species through natural selection, occurs when a selective force is intense


Distinct bands of vegetation


Items such as the food and water that an
organism uses during its lifetime.


Characteristics of the environment (such as temperature and salinity) that influence the survival of an organism but are not used by it


The proportion of salt in a solution; levels of salts dissolved in water


Particles of decaying plants and animals suspended in the water, which provide nutrients to the organisms living in it

Aquatic orgamisms

Plants and animals that live in water


All aquatic organisms that can swim against water currents


All water borne organisms that move through the water by currents


A group of plankton which are plants


A group of plankton which are animals


Very common, herbivorous zooplankton


Carnivores that eat other zooplankton


Common type of carnivorous zooplankton


Surfaces with two layers; first layer containing diatoms and seaweed, the second containing bacteria


A unique role

High marsh

The highest part of a salt marsh, where the soil is infrequently flooded

Low marsh

The lowest part of a salt marsh, where the soil is flooded two times a day with salt water

Producers (autotrophs)

Organisms able to obtain energy from the sun and use it to form energy-rich material

Consumers (heterotrophs)

Organisms which obtain energy-rich materials by eating autotrophs.

Food Chain

The pattern of energy flow, in which an autotroph produces food, a heterotroph eats that autotroph, another heterotroph eats that heterotroph, and so on.


An area of land that drains into one river, stream, or other body of water.

Runoff, groundwater, surface water

Water sources that feed watersheds.

Tidal height

The height above sea level to which the tide rises. It is affected by the position of the moon, sun, earth, and land configuration.

Tidal range

The difference in height between high and low tides.

Tertiary Treatment

The fluid from the secondary treatment is cleansed of phosphate and nitrate products that could cause pollution before the water is returned to a natural water source.

Secondary Treatment

After primary treatment, the primary effluent is passed into large aeration tanks where it is constantly agitated mechanically and air is pumped associated with fungal filaments to form mesh like structures.

Primary Treatment

The treatment step of sewage for physical removal of particles, large and small, from the sewage through filtration and sedimentation.

Nutrient Recycling

Natural processes recycle all chemicals or nutrients that plants and animals need to stay alive and reproduce.

Methane Recovery

Gas produced by bacteria in landfill is collected and used to make electricity.


The process of forming semisolid lumps in a liquid.


The phenomenon of sediment or gravel accumulating.


The process whereby fluids pass through a filter or a filtering medium.


Rough, shallow that produce rapid turbulent flows


smooth, deep bottoms that result in a slower, smooth flow in areas

Population Ecology

the study of how populations interact with their environment

Population Size

number of individuals making up its gene pool

Population Density

number of individuals per unit of area or volume

Population Distribution

the general pattern in which the population members are dispersed through its habitat (Clumped, Uniformly, Randomly)

Clumped (of population distribution)

The most common

Uniformly (of population distribution)

Dispersed (the rare kind)

Randomly (of population distribution)


Age Structure (of a population)

the relative proportions of individuals of each age (Pre-Reproductive, Reproductive, Post-Reproductive)

Community Ecology

the study of how different species interact within communities


the study of how different species interact within communities


beneficial to one species but neutral to another

Resource partitioning

the resources are divided, permitting species with similar
requirements to use the same resources in different areas, ways and/or times


an interaction that benefits one species and is detrimental to another. Note that the host is generally not killed.


an interaction that is beneficial to both species


Clear water, low conductivity


Increased production, accumulated organic matter, good fishery


Very productive, oxygen depletion, rough fish common

Oligotrophic lakes

Deep, clear, nutrient-poor lakes

Eutrophic lakes

Shallow, nutrient-rich lakes,


Area covered by water, which supports aquatic vegetation

Basin wetlands

Develop in shallow basins ranging from upland depressions to lakes and ponds that have filled in

Riverine wetlands

Develop along shallow and periodically flooded banks of streams and rivers

Fringe wetlands

Found along coast of large wetlands and seas where rising lake levels or tide causes water to flow back and forth

Streams and rivers

Bodies of water that move continuously in one direction


A tributary stream of a river close to or forming part of its source

First-order streams

Have no tributaries

Second-order streams

When first-order streams join together

Third-order streams

When two second-order streams join togther

River Continuum Concept

A model used to determine the biotic community expected as the size of the stream increases


A microoranganism, especially a bacteria causing disease


Animals that only eat plants and trees


An animal that naturally preys on others


water from the clouds fall to earth rain, snow, hail or sleet

Surface Runoff

water on the surface of the land that flows downhill into bodies of water such as streams, rivers, ponds, and lakes


rain water soaks into the ground through soil and rock layers under the soil with some remaining underground as groundwater


liquid water changes to a gaseous state as water vapor


water that has been absorbed by plants will evaporate through the leaves as
water vapor


water vapor is changed into a liquid Water vapors join dust particles to form clouds

Point Source Pollution

Pollution from a clearly identifiable location

Nonpoint Source Pollution

Pollution from many different places

Organic Pollution

decomposition of living organisms and their biproducts

Inorganic Pollution

dissolved and suspended solids as silt, salts, and minerals

Toxic Pollution

heavy medals and other chemical compounds that are lethal to organisms

Thermal Pollution

waste heat from industrial and power generation processes

Lentic Ecosystems

Still water


small body of freshwater, with no stream draining it - often fed by an underground spring


larger body of freshwater, usually drained by a stream. May be naturally occurring or man made.


region of land that holds a great deal of water for significant periods of time, and that contains specialized plants able to grow in these wet conditions

Lotic Ecosystems

flowing water


bodies of moving water, contained within a bank (sides) and bed (bottom).


natural streams of water of fairly large size flowing in a definite course or channel or series of diverging and converging channels

Light Penetration Stratification

Ponds or lakes are divided into two layers due to a decrease in light intensity with increasing depth - as light is absorbed by the water and suspended microorganisms.

Upper Photic Zone

layer where light is sufficient for photosynthesis

Lower Aphotic Zone

receives little light and no photosynthesis occurs

Temperature Stratification

occurs in deeper ponds and lakes during summer in
temperate zones.


narrow vertical zone between the warmer and colder waters where a rapid temperature change occurs

Benthic Zone

one at the lowest level or bottom of the lake including sediment surface and some subsurface layers - most of the organisms are scavengers and

Littoral Zone

hallow, well-lighted, warm water close to shore.
Has rooted and floating vegetation, and a diverse attached algal community
(especially diatoms)
Has a diverse animal fauna including suspension feeders (clams);herbivorous
grazers (snails); and herbivorous

Limnetic Zone

open, well-lighted waters away from shore

Eutrophic Zone

Has photosynthetic phytoplankton (algae and cyanobacteria), zooplankton (rotifers and small crustaceans) that graze on phytoplankton, and small fish which feed on the zooplankton.
Animals visiting this zone may include large fish, turtles, snakes, and bir

Profundal Zone

deep, aphotic zone lying beneath the limnetic zone.
This is an area of decomposition where detritus (dead organic matter that drifts in from above) is broken down.
Water temperature is usually cold and oxygen is low due to cellular respiration of decompos