farming Flashcards
what are the disadvantages of using pesticides such as insecticides, fungicides and herbicides?
they can enter an accumulate in food chains causing lethal doses to predators
they can harm other organisms living nearby
some take a very long time to break down and become harmful
what is an advantage of organic farming?
it does not use artificial fertilisers or pesticides
what does organic farming use instead of fertilisers?
animal manure and compost
what is the difference between organic and normal farming?
organic uses crop rotation to avoid build up of soil pests, nitrogen fixing crops and varying seed planting times to get a longer crop time and avoid certain times of the life cycle of insect pests
what are the disadvantages of organic farming?
the crops are smaller and the produce are more expensive
what is biological control?
using living organisms to control pests
give an example of biological control?
using ladybirds and certain wasp species to eat aphids which damage plants
how is biological control beneficial?
it can avoid the disadvantages of artificial insecticides and as they use living organisms, once introduced they usually do not need replacing
what are the disadvantages of biological control?
introduced species eating other useful species and then showing a rapid increase in their population so they themselves become pests and then spread
what are the benefits of intensive farming?
it makes used of artificial pesticides and fertilisers, is very efficient in producing large crop yields cheaply