Agricultural solutions to meet food demands

Intensive farming practices include growing high-yield crops, using fertilisers and pesticides and keeping animals indoors. Food production increases but there are occasionally some unwanted side effects.

Organic farming bans chemical inputs and can have a less harmful effect on the environment but often produces less, more expensive food.

is the production of food using nutrient-rich solution rather than soil.

Intensive farming

A tractor and a combine harvesting rapeseed

Food production can be increased by growing high-yield crops, removing other plants and pests with chemical pesticides and adding chemical fertiliser to the soil. Other intensive farming practices include keeping animals indoors, often in restricted spaces. Some of these practices have occasional unwanted side effects.

Action	Treatment	Explanation	Side effect
Remove competing plants from the crop growing area	Herbicide spray	Allows more energy to be transferred to the crop	Reduces biodiversity and may have harmful effect on health
Remove animals that feed on the crop	Pesticide spray	Prevents energy being transferred from the crop to pests	Reduces biodiversity and may harm helpful organisms
Maximise growth of farm animals	Keep animals indoors or in smaller pens	Reduces energy transferred to environment so more energy available for growth which maximises yield	Increased risk of disease

Action	Remove competing plants from the crop growing area
Treatment	Herbicide spray
Explanation	Allows more energy to be transferred to the crop
Side effect	Reduces biodiversity and may have harmful effect on health

Action	Remove animals that feed on the crop
Treatment	Pesticide spray
Explanation	Prevents energy being transferred from the crop to pests
Side effect	Reduces biodiversity and may harm helpful organisms

Action	Maximise growth of farm animals
Treatment	Keep animals indoors or in smaller pens
Explanation	Reduces energy transferred to environment so more energy available for growth which maximises yield
Side effect	Increased risk of disease

The effects of insecticides

Some don't break down quickly. DDT is an insecticide that can pass up the food chain from insects to small birds, and then from the small birds to birds of prey, like hawks. It can accumulate in the birds of prey, giving them a large amount of DDT. Concentrations of DDT in birds causes weakness in their eggs, and reduces their population. DDT is now banned because of this.

Alternatives to pesticides

is an alternative to using pesticides. By releasing a natural predator into the crop growing area, the number of pests can be reduced. This can have unforeseen consequences as the numbers of different organisms in the food web may be changed. There have been examples of the predator becoming a more serious pest than the original problem.

Food production

Some food products have been grown in artificial environments to increase productivity. Examples include growing tomatoes in glasshouses and salmon in fish farms. The benefits of this method are that the growing conditions can be monitored and controlled to improve yield but there can be some unwanted side effects.

Hydroponics

Hydroponics replaces soil with a mineral solution pumped around the plant roots.

Removing the soil means there's no risk of soil organisms causing disease but the plants have to be supported.

Monitoring and adjusting the concentrations of minerals in the solution enable the grower to control growth.

Hydroponics allows crops to be grown in regions where there's little or no soil. Due to the costs involved, hydroponics is used mainly for high-value crops.

Tomatoes grown using hydroponic system where no soil is used — Image caption,
Tomato plants growing in controlled conditions

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Feeding the human race - OCR GatewayAgricultural solutions to meet food demands