Science, Chem - Pollution Flashcards
What are living indicators for Air pollution?
Lichens
Lichens?
- help indicate if the air is polluted or clean
- grow in clean air
- need air and rainwater to live
- no roots
What are the pollutants that affect lichens?
Sulfur dioxide and Oxides of nitrogen
What are the sources of air pollution?
Traffic - Cars release oxides of nitrogen
Human population - More people use more materials and burn more fuels, releasing sulfur dioxide
Acidic gases => acid rain
Sulfur dioxide and oxides of nitrogen are both very soluble. They dissolve in rainwater making acid rain.
Problems acid rain causes
- Makes soil more acidic. Plants can’t take in essential mineral elements from the soil
- Damages decomposers. Don’t return minerals to the soil.
- Dissolve aluminium from rocks. Can poison plants and water life
- Damages leaves and seeds. Pathogens can infect plants more easily
- Slowly dissolves any structures made of chalk, limestone, or marble
How to reduce air pollution
- using catalytic converters
- this process is called: flue gas desulfurisation
How are the pollutants released?
Car engines - oxides of nitrogen
Burning Fuels - Sulfur Dioxide
what are living indicators for water pollution?
dying fish
Why are dying fish an indicator of water pollution?
Dying fish show that the water lack oxygen, and because of that the fish die.
Eutrophication
fertilizer enters water => algae multiply rapidly => plants below the surface die => micro-organisms use up oxygen as they decompose dead plants => fish die
Persistent pollutants
- Don’t break down naturally, they spread around the world in air and water
- First insecticides had persistent molecules. Not used but still cause problems
Bioaccumulation
Fish take in persistent pollutants => Seals eat fish => Polar bears eat seals
Soon the polar bears will have too much insecticides that it will eventually poison them and kill them.
How to monitor rivers?
By using living indicators: algae, fish or invertebrates.
Scientists preferably will use invertebrates because they are easy to catch and find
How does landslide relate to deforestation?
The roots of trees act like a giant net that holds the soil in place. When the trees are cut down there isn’t anything to hold it together. When it rains, the soil will be wet and loose and when the wind comes it is going to carry it away
Why does deforestation occur so much?
- to make space to grow food or keep farm animals
- to remove metal ores or coal from the ground
- for wood to use as a fuel or building material
- to grow food crops and biofuels to sell to other countries
- to build new roads and houses
Why is deforestation bad?
- plants and animals lose their habitats
- people lose the food and fuel the forest provided
- changing the local climate to become warmer and windier, which dries the soil
- bare soil is easily washed away
- lost soil fills river beds, causing more floods
Deforestation
- affects every country
- less trees => less photosynthesis => less carbon dioxide that is removed => global warming increases
Making forest more valuable
- Sustainable forests
