- monoculture = large fields of crops, all of the same type.
- this could be fields of wheat, barley, potato, rice, etc. and tend to be susceptible to pests.
- they use the crops as their own food source --> reduces productivity of farming = loss of food and financial impact on the farmer
- to over come this: Pesticides are used (these are chemicals designed to kill the pests)
PESTICIDES
Pros:
- They are chemicals = easy to obtain
- Easy to apply, not difficult for the farmer to spray it
- They are very effective
Cons:
- The chemicals are toxic = kill other plants and animals other than the pests and may be harmful to humans
- Bio-accumulation = the pesticide builds up through the food chain causing problems for animals in the higher tropic levels (e.g. DDT)
- mutation in the pest often leads to resistance = the pesticide must be applied in higher concentration and therefore, more toxic or no longer works and have to find an alternative for the pesticide.
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