b17 biodiversity and ecosystems Flashcards
what is biodiversity?
the variety of all the different species of organisms on earth, or within an ecosystem
what does a great biodiversity ensure?
a great biodiversity ensures the stability of ecosystems by reducing the dependence of one species on another for food, shelter and the maintenance of the physical environment.
a great biodiversity ensures the stability of ecosystems by?
reducing the dependence of one species on another for food, shelter and the maintenance of the physical environment.
what does the future of the human species on earth rely on?
it relies on us maintaining a good level of biodiversity
what is happening to many human activities?
many human activities are reducing biodiversity and only recently have measures been taken to try to stop this reduction.
what does rapid growth in the human population and an increase in the standard of living mean?
that increasingly more resources are used and more waste is produced.
what must happen to prevent more pollution?
waste and chemical materials need to be properly handled
where can pollution occur?
-in water from sewage,fertiliser or toxic chemicals
-in air, from smoke or acidic gases
-on land, from landfil and toxic chemicals
what does pollution do and what can this effect?
pollution kills plants and animals which can reduce biodiversity
how do humans reduce the amount of land available for other animals and plants?
by building,quarrying,farming and dumping waste
what does the destruction of pea bogs, and other areas of peat produce?
garden compost,reduces the area of this habitat and thus the variety of different animals,plants and microorganism species that live there (biodiversity)
what does the decay or burning of the peat release?
carbon dioxide into the atmosphere
what is deforestation?
cutting down trees from an area
what are two reasons why large-scale deforestation in tropical areas has occurred to?
-provide land for cattle and rice fields
-grow crops for biofuels
give one consequence of deforestation
-if we get rid of the trees, they will no longer photosynthesis and absorb co2 from the atmosphere. This means that more co2 will be left in the atmosphere where it can cause global warming
one way that forests are cleared is by burning them. why is this an issue?
as trees burn they release all the carbon they contained as carbon dioxde. This can cause huge fumes of smoke which can suffocate animals and cause huge fumes of smoke.
-contributes to global warming
whats another impact of deforestation?(biodiversity)
that habitat (tree) which had a high level of biodiversity is destroyed. reduces the level of biodiversity, can lead to entire species extinction
Explain how draining peat bogs contributes to global warming.
The draining of water allows air (and oxygen) to return to the soil
This allows microorganisms to carry out aerobic respiration and decay the organic matter
This releases CO2 which acts as a greenhouse gas, and contributes to global warming
Levels of what gases are increasing and what can this contribute to?
-levels of carbon dioxide and methane in the atmosphere are increasing and contribute to global warming
scientists are concerned citizens have put in place programme to?
reduce the negative effects of humans on ecosystems and biodiversity
whats one way to reduce the negative effects of human effects on ecosystems and biodiversity?
breeding programmes for endangered species
ways to reduce the negative effects of human effects on ecosystems and biodiversity
(protection)
protection and regeneration of rare habitats
ways to reduce the negative effects of human effects on ecosystems and biodiversity
(reintroduction)
reintroduction of field margins and hedgerows in agricultural areas where farmers grow only one type of crop
ways to reduce the negative effects of human effects on ecosystems and biodiversity
(deforestation)
reduction of deforestation and carbon dioxide emissions by some governments
ways to reduce the negative effects of human effects on ecosystems and biodiversity
(recycling)
recycling resources rather than dumping waste in landfill
