5.4 pest control

1. monoculture- a large field of crops all of the same type. eg fields of rice, potatoes. 
2. when we have a monocuture they tend to be very susceptible to pests. 
3. pests use the crop as their own food source. In doing so, it reduces the productivity in farming. E.g. loss of food and financial impact on the farmer.
4. To overcome this, you should use pesticides (chemicals)
5. Advantages of using pesticides: 
1. pesticides kill pests
2. They are easy to obtain because they are chemicals 
3. They are easy to apply 
4. They are very effective 
6. Disadvantages: 
1. Many of these chemicals present in pesticides are  very toxic therefore they will kill other plants and animals other than the pests. They can also be harmful to humans 
2. bioaccumilation- pesticide builds up in the food chain and builds problems for animals in the higher trophic levels. 
3. Mutation in the pests often leads to resistance therefore the pesticide must be applied in higher concentration, it is more toxic or it no longer works.