Effects of Humans on the Environment - LC Biology

Pollution

addition of harmful substances to the environment

Pollutants

chemicals of human origin that harm the enviornment

Carbon dioxide as a pollutant vs not

Co2 from respiration is not a pollutant

Co2 from burning fossil fuels is

Why is DDT use monitored

The sparrow hawk population suffered because there was a build up of DDT in their systems, their egg shells were too brittle and young failed to survive

If fertilisers are washed into watercourses they cause

a rapid increase in algal numbers

Euthrophication

when too many aquatic plants die at once, bacteria used oxygen when breaking them down and aquatic organisms die

Sulfur dioxide pollution

• Coal is burned, sulfur dioxide released

• sulfur dioxide dissolves in rainwater

• Acid rain formed (rain with pH under 5.5)

What does acid rain do to plants?

Stop them from photosynthesising

What plant indicates high levels of sulfur dioxide

lichens

Methods of reducing sulfur dioxide poisioning

1. Smokeless coal

2. Natural gas

3. Renewable sources of energy

Conservation

the wise management of our environment to ensure the survival of organisms and their habitats

Fishuing quota

a fixed proportion of the total allowable catch allocated to each fishing nation

Why have quotas?

• reduces overfishing fish stocks at sea

• ensures fish are able to replenish stocks

How fishing quotas help conservation

• prevent extinction

• Increases fish stock and re-establish populations

• Maintains fishing at the highest possible levels

What is the purpose of restocking

• permanent increase in population of species

• Maintains balance in the ecosystem

• Increases recreational fishing stock

Measures to protect fish population

1. Use appropriate sized nets - allows young fish to escape so they may breed

2. Strict quotas

3. Increase the price of fish - fishermen will have to catch less to earn the same living

Waste management

any substance a person wishes to dispose of, it may be solid, liquid or gas

the way we as a society, deal with our waste

Agricultural solution to waste management

1. Managing spread of slurry

2. Soil Nutrient programmes - avoid pollution from agriculture

Soil Nutrient programmes

set amount of fertiliser applied to ensure optimum yields without waste/environmental damage

Reduce aquacultural waste

• Fish bred in pollution free farms along the coast

• Dumping of waste should be monitored

How to reduce forestry waste

• Trees in forests must not be planted too close to streams/ rivers (conifers are acidic - large quantities of pine needles cause water to become acidic)

• Chemicals used in forestry must not be allowed to run off into nearby waterways

• Timbermills must recyle water used to make chip board

Traditional waste disposal method

bury rubbish in landfill sites or incinerate

Urban rubbish examples

dust, dirt, hair, paper, food scraps, metal, glass, plastic

When wastes are dumped in landfill…

bacteria and fungi break some of it down, releasing heat which can be used as fuel if trapped effectively

Landfills have…

a rubberized landfill liner

What is the purpose of a ruberized landfill liner?

Prevents leaching materials migrating downward to underlying rock

How to reduce waste

1. Reduce amount of packaging

2. Reuse as much as possible

3. Recycle as much as possible

Control of pollutants: Agri

Slurry - avoid spreading on wet, waterlogged or steep land. Do not spread within 1.5m of a watercourse

Control of pollutants: Industrial

Sulfur dioxide - fit catalytic scrubbers in chimneys

Control of pollutants: Domestic

Plastic wrapping - reduce, reuse, recycle

Benefits of conservation

• Enviornments maintained

• Endangered species preserved for reproduction

• Balance of nature maintained

• Pollution reduced