The variety of the different species on earth or within an ecosystem
what is the importance of biodiversity
To maintain the stability of an ecosystem
How does biodiversity ensure the stability of an ecosystem
It reduces the dependence on particular species for resources E.g food and shelter so that even if one species is removed other species can still survive
Why have humans’ consumption of resources and waste production increased
Rapid rise in human population
increase in standard of living
Where does pollution occur
Air
water
land
State an example of water pollutants
Sewage
fertiliser
chemicals
How does eutrophication occur
Fertilisers from farms pollute the water, causing excessive algae growth, depleting the oxygen in the water, causing other plants and animals to die
dead plants are decomposed by bacteria and the oxygen level decreases further
State an example of air pollutants
Smoke
acidic gases
State an example of land pollutants
Landfill waste
chemicals
Which human activities reduce the land available for animals and plants
Building
farming
quarrying
disposing of waste
Why have peat bogs been destroyed
To produce compost to increase food production
Why does the destruction of peat bogs greatly contribute to the greenhouse effect
Peat bogs are stores of carbon (carbon sinks) and burning them releases a large volume of carbon dioxide into the atmosphere
Why have large scale deforestation activities occurred
To provide land for cattle or rice fields
to grow crops to produce biofuels
What is the greenhouse effect
Greenhouse gases trap energy from the sun as heat in the atmosphere, keeping the temperature on earth suitable for life
What is causing global warming
The increase in levels of greenhouse gases E.g. carbon dioxide and methane, causing the temperature on earth to increase
What are the harmful effects of deforestation
Destruction of many animals habitats
releases large amounts of greenhouse gases
State the consequences of global warming
Rising sea levels
melting polar ice caps
changing weather patterns
migration of animals to find suitable habitats
tropical disease becoming more common
extinction of species
Describe the steps taken to maintain biodiversity
Breeding programmes for endangered species
protection and rebuilding habitats
replanting field margins and hedgerows
reduce deforestation
reduce carbon dioxide emissions
recycling rather than disposing in landfills
What is the purpose of replanting hedgerows and field margins
There is higher biodiversity in the margins than the fields that they surrond