7.3 Biodiversity and the Effect of Human Interaction on Ecosystems Flashcards
what is biodiversity?
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
state an example of water pollutants.
- sewage
- fertiliser
- chemicals
where does pollution occur?
- air
- land
- water
how does eutrophidcation occur?
fertiliser 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 land pollutants.
- landfill waste
- chemicals
state an example of air pollutants.
- smoke
- acidic gases
why have peat bogs been destroyed?
to produce compost to increase food production.
which human activities reduce the land available for animals and plants?
- building
- farming
- quarrying
- disposing of waste
why does the destruction of peat bogs greatly contribute to the greenhouse effect?
peat bogs are stores of carbon (carbon sinks) and burning them released 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 purpose of replanting hedgerows and field margins?
there is higher biodiversity in the margins than the fields that they surround.
what are the harmful effects of deforestation?
- destruction of many animals’ habitats
- releases large amounts of greenhouse gases