3) water pollution (FT & E) Flashcards
eutrophication: definition & cause
eutrophication is the abundance of nitrogen and phosphorus paired with a lack of oxygen that causes algae to grow in excess and create dead zones in bodies of water
Caused when waterways are polluted by nitrogen & phosphorus (fertilizers)
point vs. non-point sources
Discrete and confined sources
(Pipes from industrial or municipal facilities)
Usually treated on-site and regulated by permit
Intermittent and diffuse sources
(Runoff pollution)
Difficult to control; a variety of pollutants
Urban courses → street runoff
Rural sources → agriculture and mining
acid mine drainage: causes & impacts
Acid mine drainage is the discharge of acidic water with elevated concentrations of dissolved metals that drain from mines
Caused by sulfide minerals’ interaction with oxygen-rich water near the surface in mines
Introduces toxins to aquatic plants & animals, mobilizes other toxic chemicals, worsens water pollution
stream-floodplain restoration goals
stabilize rivers, restore riparian zones, restore aquatic habitats, improve water quality, increase denitrification, improve aquatic life
wetlands
Wetlands are areas inundated by water or saturated to depth for some days out of the year
Characterized by presence of water, hydric soil, hydrophytic plants, and services they provide to the ecosystem
(Buffers, filters, sponges, recharge areas)
Cuyahoga river fire: causes
The rise in industrialization in the late 19th century led to pollutants making their way into the river
1969 - water was oil-soaked & train spark caused the river to catch fire
N & P importance for water quality
in small amounts they provide alge & food for aquatic life
in large doses they cause hypoxia & eutrophication
saltwater intrusion: definition & causes
Saltwater intrusion is the displacement of fresh groundwater by saltwater
groundwater wells being pumped too close to coastal areas, groundwater is overpumped and saltwater finds its way to the pump
septic systems
waste collection where bacteria degrades solids and liquids undergo further underground drainage
wastewater treatment plants
Primary treatment removes 30-40% of pollutants
Screening for large particles
Mud-like settled sludge goes to the digester
Secondary treatment removes 90% of organic materials
Wastewater goes into an aeration tank
Oxygen bubbles & bacteria break down organic matter
Water goes to ozone/chlorine disinfection
advanced treatment
nutrients, heavy metals, chemicals removed
“reclaimed water”
wetlands & water pollution
Wetlands combat water pollution by absorbing and filtering toxins
More wetlands = more filtration
limiting nutrients: definition & impacts
Limiting nutrients are the scarcest nutrients in a population that stop the growth of the rest, regardless of the others’ abundance
Phosphorus limitations in lakes & nitrogen limitations in oceans cause eutrophication
They also limit oxygen growth
(Hypoxia in the Sound)
denitrification: definition & s-f reconnection
Denitrification is the conversion of nitrate into nitrogen to remove it from waterways
(NO3 → NO2 → NO → N2O → N2)
Stream restoration enhances riparian zones which facilitates denitrification
acid rain: water quality & alkalinization
Acid rain turns bodies of water acidic which reduces the water quality
As a result, the alkalinity of bodies of water goes down so efforts must be taken to increase alkalinity to counteract the acid rain (lake liming)
S-F reconnection in MD
business growth, hydrologic conductivity, water quality (human & animal use), aquatic life
Clean Water Act
Clean Water Act is a legal statute to reduce direct pollutant discharge into waterways, finance municipal wastewater treatment facilities, and manage runoff
It protects the chemical, physical, and biological integrity of waterways for shellfish, fish, wildlife, and recreation
ecosystem services
Ecosystem services are benefits that humans receive from nature that underpin food, water, security, health, and economy
acid rain & nature
Acid rain decreases water quality, turning water acidic and creating health problems for fish
(Fish gills crusted over, reproductive cycles were interrupted)
Trees were denied nutrients and were unable to grow
Birds didn’t have enough calcium so eggshells were weakened
origins of coal
Dead plants decay in swamps → get buried → get compressed until all water & organic gases are removed → concentrated carbon (coal) left behind
origins of oil
Ancient plankton & marine algae in anoxic conditions are preserved → pressure compresses it → lithification turns it into black shale (source rock) → as temp. rises kerogen turns to oil and is released
origins of natural gas
Organic matter in rocks (?) is broken down by bacteria → everything but methane is broken down → methane stays behind as volatile short-chain hydrocarbons floating on top of oil
