biodiversity and ecosystems Flashcards
what is biodiversity
biodiversity = a measure of the variety of all the different species of organisms
why is biodiversity good
a high biodiversity ensures the stability of ecosystems –> reduces interdependence
name 4 effects of the increase of the human population
effects of increase in human population:
land is used for houses, shops, industrial sites, roads –> destroy habitats and reduces biodiversity
billions of acres are used for farming –> natural animal and plant populations are destroyed
vast areas are used for quarries to obtain rocks and metal ores, reducing land available for other organisms
waste produced by humans pollutes the environment –> processing it takes up land –> affects biodiversity
what can happen if our waste is not handled properly
our waste (if not handled properly) can pollute waters with sewage, fertilisers and toxic chemicals
how can farming increase pollution
pollution is a side effects of farming –> herbicides and pesticides are poisonous and when sprayed on crops, go through soil into rivers and lakes, making their way into food chains
what is bioaccumulation
a dangerous amount of poison accumulating in predators (bioaccumulation)
how can water gain high level of nitrates and what happens if it does
waters gain a high level of nitrates from fertilisers being washed into them –> stimulates growth of algae and other water plants –> so some plants will die due to high competition for resources
what is a major source of air pollution
a major source of air pollution is burning fossil fuels
what happens if sulphur impurities are burned
fossil fuels contain sulfur impurities –> when burnt, sulfur dioxide is released –> this dissolves in rainwater to make acid rain
what are the effects of acid rain
acid rain directly damages the environment:
1.on trees it can kill leaves, buds, flowers and fruit
2. if it soaks into soil, it can destroy the roots
3. as it falls into lakes, rivers and streams, the water gets more acidic
4. buildings made out of limestone get eroded
what happens to plants and animals if acid concentration gets too high
if the concentration of acid gets too high, animals and plants can’t survive
give 4 ways which sulphur dioxide levels can be reduced
to reduce the levels of sulfur dioxide:
low sulfur petrol and diesel are used
catalytic converters
strict emmission levels are set
power plants have chimneys that clean the flue gases before they are released
what does smoke pollution contribute to
smoke pollution contributes to global dimming - the particles of soot reflect light away
what happens if smoke particles enter the lungs
the particles can get into the body and damage the lungs and cardiovascular system
what are 3 of the main reasons for deforestation
the main reasons for deforestation:
to grow crops that can be used to make biofuel (sugarcane/maize)
to grow staple foods (rice) or ingredients for cheap food (palm oil)
to rear more cattle (for the beef market)
what are 4 effects of deforestation
Effects of deforestation:
destroys habitats –> reduces biodiversity
burning them releases co2 from combustion
reduces the rate at which co2 is absorbed from the atmosphere - we lose a vital co2 sink
as dead vegetation decomposes, decomposers take in more o2 as they respire and release more co2
what is peat
peat = made up of plant material that cannot decay completely due to conditions being acidic and insufficient o2
-peat lands and peat bogs are a massive carbon store
What are the uses of peat
peat is burnt as fuel and is also added to soil to improve conditions for seed germination and increased food production
is peat renewable or non renewable and why
peat forms very slowly –> it’s being destroyed faster than it’s made –> non-renewable
what is global warming
global warming = the average temperature of the earth getting warme
what are the biological consequences of global warming
Biological consequences of global warming:
loss of habitat –> low-lying land will be flooded
sea levels rising
changes in migration patterns - seasons may change
reduced biodiversity - as climate changes, species that can’t cope and survive will become extinct
