water quality - vocab

lentic

still water

lotic

flowing water

epilimnion

warm surface layer that interacts with sunlight and wind

thermocline

• middle layer where temperature changes rapidly with depth

hypolimnion

cold bottom layer that remains stable and is often devoid of light

evaporation

Sun heats water, changes from liquid to vapor & rises into the atmosphere.

transpiration

Plants release water vapor from their leaves into the air

condensation

as water vapor rises, it cools into tiny droplets forming clouds

precipitation

Droplets in clouds combine, fall back to the Earth as rain, snow, sleet, or hail

runoff

Water that falls onto ground flows & returns to oceans, rivers, & lakes

watershed

 land area draining to a common body of water

agricultural runoff

Fertilizers lead to eutrophication/algal blooms

urban stormwater runoff

Carries pollutants (oil, grease, metal, trash, pathogens) from impervious surfaces (roads, rooftops) into waterways

industrial discharge

Factories release chemicals, metals (lead, mercury), and high-temperature water

sewage treatment plant discharge

Sewage introduces nutrients, pathogens, pharmaceuticals, and endocrine-disrupting chemicals

mining impacts

Acid mine drainage (sulfuric acid/heavy metals) severely acidifies water

construction site erosion

Exposed soil is easily eroded by rain

acid rain & atmospheric deposition

Air pollutants (sulfur dioxide, nitrogen oxides) from industry and vehicles react

thermal pollution

 Discharge of heated water

bioaccumulation

toxins accumulate in organismsmio

biomagnification

toxins become more concentrated up the food chain

best management practices (BMP)

reducing fertilizer use, improving wastewater treatment, controlling erosion

riparian buffer zones

vegetated areas along waterways filter runoff, stabilize banks, act as a natural pollution control system

eutrophication

nutrient enrichment → algal bloom → DO crash → kills fish

harmful algal blooms (HABs)

produce toxins that are harmful to humans & other animals

hypoxic zones

decomposition of these blooms by bacteria consumes DO, creating areas where most aquatic life cannot survive

turbidity

cloudiness of water caused by suspended particles

cogaulation

adding chemical coagulants to water to destabilize colloidal particles (clump together)

flocculation

gentle mixing process that encourages the growth of clumping

sedimentation

heavier flocs settle out of the water due to gravity

filtration

solid particles in a liquid or gaseous fluid are removed by a filter

disinfection

kill/inactivate remaining pathogens

primary treatment

physical processes

secondary treatment

biological treatment

tertiary treatment

remove remaining pollutants

competition

organisms vie for the same limited resources

predation

one organism hunts and kills another for food

mutualism

both organisms benefit from the interaction

commenalism

one organism benefits, the other neither helped nor harmed

parasitism

one organism benefits at the expense of another

keystone species

species that has disproportionately large effect on its environment

carrying capacity (K)

maximum population size that can be sustained indefinitely

exponential growth

population growth that occurs when resources are unlimited — J-shaped curve

logistic growth

population growth that occurs when resources are limited — S-shaped growth

density-dependent factors

factors whose effects on the size or growth of population vary with the population density

density-independent factors

factors whose effects on the size or growth of the population are not dependent on the population density

r-strategists

many offspring, low survival

K-strategists

few offspring, high survival

traditional ecological knowledge (TEK)

indigenous knowledge systems based on long-term observation and intergenerational transmission