lecture 30- pollution Flashcards
What is a contaminant?
Presence of, or elevated concentrations of, a potentially toxic
substance in the environment
What is pollution?
Contamination that results in measurable effects on natural
processes (abiotic or biotic)
What is a primary pollutant?
Pollution that is produced directly from a source
What is a secondary pollutant?
Primary pollutants undergoing chemical changes within a
natural reservoir, forming a different form of pollutant
What is bioaccumulation?
Toxin levels increasing in in the body tissues of an individual during its lifetime
What is biomagnification?
Toxin levels concentrating in higher trophic levels
Do natural or anthropogenic have more impact globally?
anthropogenic
What are the main groupings of pollution?
1- Land pollution
2- Air pollution
3- Water pollution
4- Energy pollution
What is land pollution?
Deterioration of land surfaces (above or below ground) as a result of contamination
Land pollution is often the source of contaminants which enters water or air reservoirs
What are examples of land pollution?
- Landfill
- Soil contamination
- Pesticides and herbicides
What is litter/landfill?
Disposal area for solid waste
What is the difference between land raising and landfilling?
Piling solid waste on the surface → land raising
Digging a hole for the burying of solid waste → landfilling
How are modern landfills designed?
Multiple layers of protection to contain solid waste and leachates within the landfill
Designed to by buried once filled and converted to greenspace
Why is DTT dangerous?
DDT can both bioaccumulate and biomagnify
Entered food chains through water and soil contamination
How has DTT affected birds?
High levels of DDT interfered with calcium metabolism
Female birds contaminated with high levels of DDT produced eggs with eggshells too thin to incubate. The female would crush the eggshells during incubation.
Resulted in significant declines in several bird species.
What is water pollution?
Pollution of blue water resources
What are examples of water pollution?
- Human sewage
- PCBs
- Mercury
- Heavy metals
- Fertilizers
- Oil spills
- Pharmaceuticals
What are the sources of mercury?
Mercury cycles through the atmosphere, water, and soils
Natural sources → volcanoes, fires, chemical weathering
Anthropogenic activities → coal burning, mining, waste incineration
Why is mercury dangerous?
Within water systems, bacteria convert ionic mercury to methylmercury
Methylmercury both bioaccumulates and biomagnifies. It can cause significant damage to the brain and central nervous system.
What characterizes phosphorous?
Phosphorus (P) is a major limiting nutrient in plant and algae growth.
P is incorporated into fertilizer in modern agriculture
Plants do not absorb all P in fertilizer
Why is phosphorus dangerous?
Excessive runoff of P enters waterways: Results in eutrophication
Excessive P in waterways causes an algae bloom
- As algae die: Result in large increase in decomposition by bacteria
Decomposition requires oxygen
- Removes large amounts of oxygen from water
Fish die from lack of dissolved oxygen in water
How do pharmaceuticals contribute to water pollution?
Medicines and artificial hormones for human and animal use
- Can be directly released during production
- Can pass through the body and be excreted in urine
Some pharmaceuticals enter water systems
- Can enter food chains or have direct impact on wildlife
- Can be reintroduced back into drinking water
- Many older water treatment systems are not designed to remove pharmaceuticals
What is air pollution?
Pollutants suspended in, or derived from, the atmosphere
What are examples of air pollution?
Greenhouse gases
Smog
- Particulates
* Heavy metals
- Lead
* Acid rain
How does lead contribute to air pollution?
Anthropogenic lead is released into the air during coal combustion, manufacturing, incinerators, jet fuel
Lead bioaccumulates:
- Brain damage
- Lower IQ
- Can effect babies in utero
-Greater effect in children with developing nervous systems
- Can become stored in bones and release years after initial exposure
Explain how acid rain forms.
Sulfur dioxide (SO2) and nitrogen oxides (NOx) in the atmosphere react with atmospheric molecules (H2O, O2) to form sulfuric and nitric acids
Nitrogen oxides → agriculture
Sulfur dioxides → industry
Acids mix with precipitation, fog, snow
- Acid rain (fog and snow)
Explain how acid rain contributes to air pollution.
Acid rain directly affects pH of soils and freshwater ecosystems.
In soils:
- Removes important plant nutrients through chemical reactions
In freshwater ecosystems:
- Mortality of species throughout trophic levels
- Juvenile forms of species generally more vulnerable
What is energy pollution?
Pollution resulting from the transfer or production of energy in systems
What are examples of energy pollution?
Noise, light, thermal energy
What is thermal pollution?
Anthropogenic change of temperature in systems
Can occur in heavily managed water systems and near powerplants that require water as coolant.
What is noise pollution?
Excessive noise contaminating systems
How can noise pollution affect the environment?
All cetaceans communicate by sound
Shipping and other marine activities:
- No part of the ocean is without noise pollution
Involved in:
- Increased stress
- Limiting ranges
- Suspected cause of mass stranding
