Thousands of years ago many people grew small amounts of crops and raised small numbers of livestock to feed their families. As we have moved from small villages into larger towns and cities farming has become modernised to meet the demands of a larger and more urban lifestyle.
Intensive farming uses machines, fertilisers, man-power and high-yield crops to maximise the amount of food produced. Farmers growing arable crops often specialise in growing only one crop to maximise their profits. This is called monoculture. It can quickly reduce key nutrients in the soil and lowers biodiversity.
Hedgerows have been removed from many fields to make them bigger and easier to tend to by big machines. This also reduces biodiversity. Crops are often sown, treated and harvested by machines which create pollution, and fertilisers are added to fields in larger amounts which can cause eutrophication.
Intensive farming can also mean keeping livestock in smaller pens with regulated temperatures. This reduces the energy they need for movement and temperature regulation and so maximises their size and yield. Some animals are fed high protein foods to increase their growth. They are often fed antibiotics in their food to prevent diseases. Many scientists think this is leading to antibiotic resistance in bacteria.
Advantages and disadvantages of intensive farming practices:
|Higher yields||Reduction in biodiversity|
|Cheaper food for the consumer||Creates pollution|
|More efficient use of food||Risk of antibiotic resistance|
|Quality control easier||Considered unethical by some people|
Many people object to intensive farming because it reduces biodiversity and increases pollution. More recently some farms have become organic to address this. Organic farmers do not use machines to the same extent as intensive farming. They do not apply pesticides to their crops and use natural fertilisers such as compost and manure. They rotate their crops to avoid monoculture.
This image shows some of the changes in crops planted that happen during crop rotation to increase yield, promote biodiversity and help keep soils heathy.
Because of this, organic food is often more expensive than intensively farmed food, and many people are willing to pay more for the perceived benefits.
The demand for more meat has resulted in increased intensive farming of animals such as cattle, pigs and chickens. This has an impact on food security because animal farming wastes more energy because the food chain is longer. It is much more efficient to grow crops so more people can be fed per area of land. In addition, farmed animals are often fed crops which could be consumed by humans.
Pathogens including bacteria, fungi and viruses may infect the crops or farm animals and will reduce the yield of crops and reduce the food availability for the human population. New pathogens may reduce yields dramatically as the crops or animals may not be resistant. New diseases may lead to crop failure and reduced food production. Also new pests such as insects may damage the growth of crops, reducing yield and food security.
Sustainability means maintaining the needs of the human population into the future. This includes food security and fuel for vehicles and industry. Fuels such as diesel and petrol made from crude oil are non-renewable and are running out. An alternative fuel is biofuel such as bioethanol which is made by fermenting sugar from corn or sugar cane. Therefore these biofuel crops provide a renewable fuel. They have a negative impact though, as they are often grown on land which could be used for growing crops for food.
Farming is expensive in terms of land costs, machinery, fuel and fertilisers. As costs increase, many farmers find it too expensive to continue farming so farms shut down and food production stops. This has a negative impact on food security.