Unit 8 Flashcards
an area where all the water contained drains into a common body of water, such as a river, lake, or ocean
watershed
A single source of pollution that you can “point” to
EX: a smokestack or waste discharge pipe
Point Source
A source of diffused (mixed/diluted) pollutants, therefore difficult to identify, commonly referred to as runoff
Non-Point Source
U.S. federal law that regulates the discharge of pollutants into the nation’s surface waters, including lakes, rivers, streams, wetlands, and coastal areas.
Clean Water Act
Type of species that are sensitive to specific environmental conditions & have a limited range of tolerance
population growth or reduction indicates environmental change
indicator species
A type of indicator species that live in an aquatic ecosystem for a long time, showing the chronic effects of pollutants
Macroinvertebrates
a scale for showing the quality of an aquatic environment by indicating the types and amounts of organisms in a representative sample
Biotic Index
A high biotic index indicates…
the presence of many pollution-sensitive organisms, therefore an unpolluted environment (Low BOD)
A low biotic Index indicates…
an abundance of pollution-tolerant organisms, therefore a polluted environment (High BOD)
The amount of _______ is used as a standard measure/indicator of disease potential
fecal coliform bacteria
The growth of the fecal coliform bacteria will cause a(n)…
increase in the biological oxygen demand (BOD)
High BOD or Low DO means high amount of bacteria
What produces BOD?
Dead organic waste/matter
Two most famous oil spills
Deepwater Horizon Oil Spill
(Gulf of Mexico) &
1989 Exxon Valdez Oil Spill (Alaska)
How long do environments need to recover from oil spills?(land or water)
days to decades, depending on size & scale of a spill
How do oil spills impact the surrounding organisms
-in marine waters: organisms to die from the hydrocarbons
-Oil on the water surface can coat feathers & fur
-Sunken oil components kill bottom-dwelling organisms
Ways to clean up oil spills:
-Oil absorbent booms
(absorb oil)
-Skimmer Boats
(collect w/vacuum)
-genetically engineered bacteria
(break down oil)
Main source of heavy metals polluting the environment
the burning of coal
vocab word
the use of plants to take in heavy metals and other contaminants in the environment (causes biomagnification in the food web)
Phytoremediation
greatest water pollutant by mass
sediment
Eutrophication leads to “hypoxia” which is
Low DO
(low amount of O2)
Dissolved oxygen concentrations drop quickly downstream (aka become runoff) from a point-source of organic matter due to…
breakdown of organic compounds by bacteria
What does an endocrine disruptor do?
blocks the receptor protein binding site of a hormone so that the cell cannot receive signals
chemicals that can interfere with the endocrine (hormone) systems of animals (affects brain & reproductive systems)
Endocrine disruptors
Endocrine disruptors can lead to:
-developmental malformations (including: birth defects & gender imbalances, learning disabilities, mutations)
-interference with reproduction (like low fertilization)
-increased cancer risk
-disturbances in the immune & nervous systems
Endocrine disruptors are found in many products, including:
Plastic bottles/containers
liners of metal food cans
Detergents
flame retardants
Food
Toys
Cosmetics
Soaps
Fragrances
Pesticides
What do Soil and Plants do for the wetlands?
filter out sediments in the water
What do wetlands do to support local environments
-soak up floods,
-clean water
-host wildlife
Wetland Characteristics
-Brackish Water: (mix of salt & fresh)
-hydric soil (water saturated soil)
-Supports many many species
Threats to Wetlands & Mangroves
-Agriculture
-aquaculture
-commercial development
-dam construction
-overfishing
-pollutants from agriculture or industrial waste
Wetlands provide a variety of ecological services, including:
water purification
flood protection
provides resources
habitat
A beach community was recently negatively affected by a hurricane. Community leaders are looking for a potential solution to prevent damage from future hurricanes.What solutions would best address the issues of greatest concern in the community?
Planting mangrove forests
What is a way to potentially eliminate one of the greatest threats to the world’s mangrove wetlands?
restrict aquaculture in those areas
A state highway was constructed over wetlands. The state obtained a permit to fill the existing wetlands in accordance with the provisions of the Clean Water Act in 1972, and agreed to create another wetland. This trade-off approach to addressing an environmental issue is known as what?
mitigation
What two excess nutrients cause eutrophication?
nitrogen & phosphorus
How does eutrophication lead to hypoxia?
When algal bloom dies, microbes digest the algae, along with the oxygen in the water, leading to a decrease in the dissolved oxygen levels in the water (hypoxia) which can result in large die-offs
Hypoxic waterways
bodies of water that are low in DO
How to prevent eutrophication
-dredging out lakes to deepen them
-pumping oxygen into the lowest layers of water
-introducing herbicides and/or insects that eliminate certain nuisance plants
What is a Oligotrophic body of water
-low amounts of BOD
-high DO
-stable algae populations
Causes of Thermal Pollution
-Nuclear waste (hot water)
-soil erosion
-Deforestation reduces shade
-Water runoff from paved surfaces
-Volcanoes
-geothermal activity
-lightning
Higher water temps:
lower DO level
Lower water temp:
higher DO level
DO levels are higher in moving water
Impacts of Thermal Pollution
-warm water holds less DO which can lead to hypoxia & die-offs
-temp variation can impact the survival of low-tolerant eggs & larvae
-Feeding, Breeding, & migration patterns are altered
DDT
pesticide almost made the bald eagle extinct due to weak shell production
PCBs effects
-cancer
-damages the immune, reproductive, nervous, & endocrine systems
Sources of POPs
Industry, Waste, Traffic, Agriculture
pollutants that do not easily break down in the environment because they are synthetic, carbon-based molecules (such as DDT and PCBs) that can travel over long distances via wind and water before being redeposited. Another example is Lindane, a chlorinated hydrocarbon commonly used as an insecticide.
Persistent organic pollutants (POPs)
POP transportation methods
-Air
-water
-rain
-snow
Why are POPs toxic for organisms?
POPs are soluble in fat, allowing them to accumulate in organisms’ fatty tissues
Rachel Carson
highlighted the dangers of DDT in her 1962 book, Silent Spring
used DDT to share the disastrous consequences of the overuse of insecticides
-raised enough concern that Congress established the Environmental Protection Agency (EPA)
TLDR: increased public awareness of the risks of using pesticides
Effects of Bioaccumulation
eggshell thinning, developmental deformities in top carnivores of the higher trophic levels.
the absorption of a substance by a single organism at a rate greater than the rate of elimination
Bioaccumulation
the increasing up the trophic levels of food chains and food webs
Biomagnification
Effects of biomagnification
cancers and issues with the reproductive, nervous, and circulatory systems
DDT, Mecury, PCBs are known to biomagnify
Why would a US citizen test positive for DDT if it’s banned in our country?
other countries that export produce to the United States still use DDT
Litter that reaches aquatic ecosystems, can cause:
intestinal blockage and choking hazards for wildlife and introduce toxic substances to the food chain
Anthropogenic causes of eutrophication
agricultural runoff and wastewater release
any discarded material that is not a liquid or gas, generated in domestic, industrial, business, and agricultural sectors
Solid Waste
Largest single component of municipal solid waste waste in the US
Paper
most common method of waste disposal
landfills
The decomposition of food and other organic matter produces:
Methane, a gas that can be collected and used to power nearby buildings & homes
landfills must meet stringent design, operation and closure requirements established under the…
Resource Conservation and Recovery Act (RCRA)
When you think “RCRA” think “Hazardous Waste”
Disposal Method that leads to large trash islands & harm wildlife from entrapment & consumption
Ocean dumping
Disposal Method that makes trash take up less space but releases air pollutants
Incineration
Disposal Method where decomposition relies on the composition of the trash & the presence of microbes to break them down
Landfills
A sanitary municipal landfill consists of:
-bottom liner
(made of plastic or clay)
-storm water collection system
-leachate collection system
(for protecting groundwater)
-cap (for methane)
-methane collection system
water has percolated through a solid and leaches out ___
Leachate
More contaminants are leached when solid waste is in small particles and put in water than when the particles are large because…
because smaller particles have a larger surface area per unit volume than larger particles
Plastics are a problem in the waste system because
they decompose slowly, if at all, and persist as solid waste
Advantages of incineration:
-Waste reduction
-Reduced need for landfills
-Placed closer to source so less transportation required
-Source of energy
-No groundwater contamination
Disadvantages of incineration:
-Not very affordable
-Generates air pollution
-Discourages recycling & waste reduction
What happens when rubber tires are illegally dumped and left out in piles?
can become breeding grounds for mosquitoes that can spread disease
Act that authorizes the President to respond to releases or threatened releases of hazardous substances into the environment
Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)
also known as Superfund
What happens when items are placed in recycling that cannot be recycled?
the cost of recycling increases
advantage of recycling aluminum produced from recycled metal
uses much less energy than is required for its production from aluminum ore
What materials would be best suited for incineration to reduce total volume, produce energy, and have minimal release of air pollutants?
Wood
TorF: Food scraps & sewage are not considered hazardous waste on their own
True
The high cost of recycling is mainly due to…
sorting
(saleries of people employed to sort trash)
The most energy efficient method to reduce global demand on minerals
the use of reusable containers
Drawbacks to composting (making food scraps into fertilizer) include…
odor & rodents
The combustion of gasses produced from decomposition of organic material in landfills can be used to
turn turbines (generate electricity)
(reducing landfill volume)
Methods of Integrated waste management
reusing
recycling &
composting
Primary treatment of sewage is…
the physical removal of large objects in waste water
Main purpose: lower turbidity (filter out suspended particles)
often with of screens and grates & the settling of solid waste in the bottom of a tank
Secondary treatment of sewage is,
a biological process in which bacteria break down organic matter ( nitrates, phosphorous, organics & ammonia) into carbon dioxide & inorganic sludge which settles in the bottom of an aerated tank
main purpose: provide O2 (be aerated) to keep microorganisms (bacteria) alive to remove nitrates, phosphorous, organics & ammonia
Tertiary Treatment of sewage is,
use of ecological or chemical processes to remove any pollutants/bacteria left in the water after previous treatments (chlorine, ozone, or UV light is used to kill bacteria)
main purpose: remove pathogens & nutrients
What diseases are spread through ingestion of contaminated water or food?
cholera & dysentery
dysentery: aka Traveler’s diarrhea or Montezuma’s revenge
What are the two main water tests that would indicate the water is polluted with sewage?
-Fecal Coliform Bacterial Test: indicates a presence of feces from a warm blooded animal
BOD (Biological Oxygen Demand) Test: amount of O2 consumed by bacteria & other microorganisms decomposing organic matter under aerobic (oxygen- present) conditions at a specified temperature
What problems are associated with untreated wastewater (sewage)?
Eutrophication & Petrification
[Petrification is (aka when the algae die) caused by eutrophication]
Nitrogen is more likely to be high in…
Phosphorous is more likely to be high in…
Nitrogen: saltwater
Phosphorus: freshwater
Things removed by wastewater treatment:
Suspended solids;
Organic (biodegradable) material;
Nutrients (nitrogen and phosphorous);
Pathogenic organisms (expressed as E. Coli)
Things that cannot be removed by wastewater treatment:
-drugs, medicines, and other chemicals
(making it unusable as fertilizer)
-organic chemicals (POPs)
-Heavy metals
Water Softeners take out
calcium, magnesium, & iron
Physical treatment processes include:
Primary Treatments:
-sedimentation
-flotation
-screening
-filtration
Tertiary treatment:
-Membrane filtration
Biological treatment processes include:
Secondary Treatments:
-trickling filters
-biofilters
-activated sludge
-Denitrification
Tertiary Treatments:
-Septic tanks
-Ponds
anaerobic processes – absence of dissolved oxygen
Chemical treatment processes include
Tertiary Treatments:
-ozonation (kills bad bacteria through ozone infusion)
-chlorination
-Ultra Violet Radiation (disinfection process of passing Ultraviolet (UV) light through water)
-Chemical Precipitation (lime, Fe, Al salts, Struvite formation)
-Adsorption
an outdoor tank that separates solids from liquid, digests (biochemically changes) & stores organic matter through a period of detention then discharges clarified liquid into a drain field (absorption field or field bed) from a piping system allowing seepage into soil where it is then further treated by natural processes of oxidation & filtering.
when water reaches a freshwater supply, it should be safe for other uses
Septic Tank
Ammonia is in urine & the ____ from it helps ______
nitrogen from it helps plans grow
Why do fish die during an algal bloom?
Decreased O2 (DO) [aka hypoxia] causes asphyxiation
LD ÷ LC =
higher means ____ toxic, lower means ____ toxic
higher = less toxic
lower = more toxic
Lethal dose 50% (LD50) is the dose of a chemical that is lethal to
50% of a population
graph that describes the effect on an organism or mortality rate in a population based on the dose of a particular toxin or drug
dose responce curve
a type of cancer caused mainly by exposure to asbestos
Mesothelioma
elevated levels of tropospheric ozone causes…
Respiratory problems and decrease in overall lung function
interaction of different substances where the combined effect is greater than the sum of the effect of the separate substances
Synergism
The activity with the health risk most likely to be overestimated by the public in the US is:
living near a power plant
As equatorial-type climate zones spread north and south into what are currently subtropical and temperate climate zones…
pathogens, infectious diseases, and any associated vectors are spreading to new areas
what areas are likely to lack sanitary waste disposal leading to havens and opportunities for the spread of infectious diseases?
Poverty-stricken, low-income
a disease carried by organisms infected with its bacteria. It is transferred to humans via the bite of an infected organism or through contact with contaminated fluids or tissues
plague
a bacterial infection that typically attacks the lungs. It is spread by breathing in the bacteria from the bodily fluids of an infected person
Tuberculosis
a parasitic disease caused by bites from infected mosquitoes. It is most often found in sub-Saharan Africa
Malaria
virus transmitted to humans via bites from infected mosquitoes
west nile virus
transferred by inhaling or touching infected fluids
Severe acute respiratory syndrome (SARS) [form of pneumonia]
a viral respiratory illness that is transferred from animals to humans
Middle East Respiratory Syndrome (MERS)
a virus caused by bites from infected mosquitoes that causes major birth defects. It can be transmitted through sexual contact
Zika Virus
Factors that affect the spread of diseases
-flooding, (contaminates water supplies with raw sewage)
-global warming, (can transfer carriers of disease from tropical to more temperate areas)
-introduction/spread of insect vectors (caused by gw & cc)
-rural poverty, (causes people to condense in urban areas)
When scientists discover the existence of an emerging infectious disease such as SARS (severe acute respiratory syndrome), they must take immediate steps to determine the cause of the disease and the method of transmission. These initial steps would include what?
Tracing the medical & travel history of the infected
Ticks are vectors for various diseases, they acquire the disease-causing organisms from what?
feeding on host animals
