C14-The earths Resources Flashcards
what does finite mean
will run out eventually
define renewable
we can replace them as we use them
define sustainable
meets the needs of the current generation without thinking about future generations
what do we use earths resources for
warmth
shelter
food
transport
finite resources are processed to get us
energy and materials
natural resources and agriculture provides
food
timber
clothes
potable water must have low levels of
salts and microbes (it isn’t pure)
what do we do to rainwater in lakes, rivers and reservoirs to treat it
1- filter it to remove insoluble solids
2- sterilise by chlorine, ozone or UV light to kill microbes
how do you treat sewage water
1- screening and grit removal
2- sedimentation
3- anaerobic digestion of sludge
4- aerobic treatment of affluent
what do you do to industrial and agricultural water
remove organic matter and harmful chemicals
what can you do to treat salt water
desalination either by distillation or reverse osmosis
what are the downsides of desalination
lots of energy required
