Recall the examples or pesticides
Insecticides to kill insects
Fungicides to kill fungi
Herbicides to kill plants
What does intensive farming mean?
It means trying to produce as much food as possible from land, plnats and animals available.
Describe how intensive farming methods can increase productivity limited to:
- fish farming - breeds huge numbers of fish in enclosed nets in the sea or lakes
- glasshouses
- hydroponics - growing plants without soil
- battery farming - raising chickens in cages
Describe organic farming methods
- no artificial fertilisers
- no pesticides
Describe how pests can be controlled biologically by introducing predators
Biological control reduces the population of the pest but does not completely remove the pest
Explain the disadvantages of using pesticides
- pesticides may enter and accumulate in food chains
- pesticides may harm organisms which are not pests
- some pesticides are persistent
Describe how plants can be grown without soil (hydroponics)
Plants grow with their roots in a solution then minerals needed for healthy plant growth are added to the solution.
Describe possible uses of hydroponics
Glasshouse tomatoes
Plant growth in areas of barren soil
Drawback and advantage of intensive farming
May be efficient but raises ethical dilemmas
Explain the advantages and disadvantages of hydroponics
- better control of mineral levels and disease
- lack of support for plant
- required addition of fertilisers
Describe organic farming methods
- use of animal manure and compost
- crop rotation including use of nitrogen-fixing crops
- weeding
- varying seed planting times
Explain the advantages of organic farming
- livestock have space to roam
- food crops and the environment are not contaminated with artificial fertilisers or pesticides
- soil fertility is maintained through the use of organic fertilisers, and the soil erosion is limited
Explain the disadvantages of organic farming
- less efficient as some crops and the energy they contain are lost to pests and diseases
- free-roaming livestock use mire energy and lose more body heat. This requires more food to increase their body mass.
Explain the advantages of biological control
No need for chemical pesticides
Does mot need repeated treatment
Disadvantages of biological control
Predator may not eat pest
May eat useful species
May increase out of control
May not stay in the ares where it is needed
Explain how removing one or more organisms from a food chain or web may affect other organisms
Their population will decrease
What are pesticides?
They kill pests which are any organisms that damage crops
Explain how intensive food production improves the efficiency of energy transfer by reducing energy transfer
- to pests, including competing plants (weeds)
- as heat from farm animals by keeping them penned indoors (battery farming) so that they are warm and move around less
