Session 3: Pollution Flashcards
Overall, describe water pollution.
Can occur from urban, industrial, or agricultural sources and enters ground water or directly into surface waterways from runoff. Some pollution alters the water pH, temperature, and turbidity (higher amounts of solid particles/cloudiness/sediments), and can also add harmful substances to the water.
What are the elements and sources of water pollution?
sediment, sewage, infectious particles, organic compounds, thermal changes, radioactive pollution, inorganic chemicals, plastic waste, and inorganic plant nutrients.
How does sediment count as water pollution?
soil erosion (e.g. top soil being washed away) and silt/sediment built up can alter waterways and their habitats.
How does sewage count as water pollution?
while treatment is often carried out and minimises the impact, human waste, soaps, and detergents are often released into waterways and the oceans
How do infectious particles count as water pollution?
disease causing microbes from animals and humans can be a major issue particularly with drinking water (can come from sewage, etc.)
How do organic compounds count as water pollution?
organic compounds, meaning they come from living matter, including fossil fuels, such as oil spills and manufacturing waste products such as dioxins can be released into waterways and be toxic to organisms.
How do thermal changes count as water pollution?
definition: heat (pollution)
some industries like power generation can increase water temperatures which can alter habitats and reduce oxygen levels.
How does radioactive pollution count as water pollution?
mining and nuclear power stations can release dangerous levels of radioactive material, generally as waste that pollutes the soil and waterways that is dangerous because it can last a very long time
How do inorganic chemicals count as water pollution?
mining, acid rain, heavy metals (mercury, arsenic, etc.) and many chemicals are toxic and can contaminate water (they sometimes come from the soil)
How does plastic waste count as water pollution?
every year, about 8 million tons of plastic waste escapes into the oceans from coastal nations and plastics can take up to 400 years to break down
How do inorganic plant nutrients count as water pollution?
artificial fertilisers with large amounts of nitrogen and phosphorous can lead to accelerated nutrient enrichment, causing algal blooms and weed growth (eutrophication)
Define eutrophication and where and why it occurs.
The enrichment of an ecosystem (typically aquatic) with chemical nutrients (nitrates, phosphates, etc.). It is a common occurrence in Australia and can be caused by nutrients being leached from soil by rainfall or released as part of sewage. It is a common occurrence around agricultural land.
What are the effects of eutrophication?
- algal blooms (which can block sunlight for other plants and kill them)
- a subsequent spike in the number of decomposers as algae dies
- increased biochemical oxygen demand (BOD) due to the high rate of decomposition by saprotrophic bacteria (they consume available quantities of dissolved oxygen leading to deoxygenation)
- all of the above stress the survival of aquatic organisms, potentially leading to reduction in biodiversity
Describe air pollution.
Consists of gases, liquids, or solids present in the atmosphere at levels high enough to be harmful to organisms. It is concentrated around areas of high/dense human population and industry, and can sometimes affect enclosed/indoor environments, e.g. buildings, cars, etc. Can be caused by forest fires, volcanic activity, burning of fossil fuels, industry, and vehicles.
What is smog?
Sunlight reacting with a mixture of pollutants from industry and vehicles.
What are the air pollutants?
carbon monoxide, hydrogen sulfides, sulfur dioxides, nitrogen oxides, smoke, lead, ozone, and hydrocarbons.
Describe carbon monoxide air pollution.
Caused by power plant and industrial emissions, fossil fuel combustion, petrol and diesel combustion, and bushfires. Carbon monoxide poisoning limits the body’s ability to transport oxygen to where it needs it and can cause health problems ranging from headaches to death.
Describe hydrogen sulfides air pollution.
Caused by fossil fuel combustion, oil refineries, wood pulp processing, power plant and industrial emissions, and oil and natural gas extraction. Can cause eye and respiratory system irritation and can be life threatening depending on its concentration.
Describe sulfur dioxides air pollution.
Caused by power plant and industrial emissions, fossil fuel combustion, and volcanoes. Mainly affects the respiratory system (lung function) but can also irritate the eyes.
Describe nitrogen oxides air pollution.
Caused by power plant and industrial emissions, burning fossil fuels, and petrol and diesel combustion engine emissions. It forms photo-chemical smog which can irritate the eyes and nose, also affects plant growth.
Describe smoke air pollution.
Mainly caused by Power plant and industrial emissions, but also burning fossil fuels, and petrol and diesel combustion engine emissions. Can cause irritation or more serious effects on cardiovascular and respiratory systems.
Describe lead air pollution.
Caused by petrol and diesel combustion engine emissions, and ore and metals processing. Lead pollution/poisoning causes damage to the nervous system, convulsions, and comas.
Describe ozone air pollution.
In the presence of direct sunlight, pollution from industry and vehicles react to form ozone (caused by vehicles, industry emissions, fossil fuel combustion). Can cause sick building syndrome and other damage to respiratory system.
Describe hydrocarbons air pollution.
Caused by petrol and diesel combustion engine emissions. Can cause pneumonia and other effects to respiration.