7.3 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 organism
how does biodiversity ensure the stability of an ecosystem
it reduces the dependence on particlular species for resouces (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 for living
where does pollution occur
air
land
water
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 decompised by bacterial 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
- builidng
- 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
and burning them relases a large volume of carbon dioxide into the atmosphere
what is the grrenhouse 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 level of greenhouse gases
causing the temperature on earth to increase
state the consequences of global warming
rising sea levels
melting polar ice caps
changing weather patterns
migration of animals to find suitable habitats
tropical diseases becoming more common
extinction of species.
