Food: the demand for food and food security, the environmental impacts of agriculture including soil degradation, and sustainable approaches to food production.

What this dot point is asking

The SQA wants you to explain the demand for food and the meaning of food security, the environmental impacts of agriculture (especially soil degradation), and the sustainable approaches to producing food. This applies the sustainability framework to the most basic human need.

Demand for food and food security

The demand for food is rising because the population is growing and, as incomes rise, diets shift towards more resource-intensive foods such as meat. Meeting this demand sustainably is the central challenge.

Food security can be threatened by population growth outpacing production, climate change (drought, floods, shifting growing seasons), soil degradation reducing the productive area, water scarcity, loss of crop genetic diversity, and poverty or conflict limiting access even where food exists.

Environmental impacts of agriculture

Intensive agriculture has raised yields enormously but carries environmental costs:

Soil degradation is central: ploughing and removing vegetation expose soil to erosion by wind and water; monoculture (growing one crop repeatedly) strips specific nutrients and lowers organic matter; heavy machinery causes compaction; and over-irrigation can cause salinisation. Because soil forms so slowly, degradation steadily shrinks the land available to grow food.

Sustainable approaches to food production

Sustainable food production aims to keep yields high while protecting the resource base for the future:

• Crop rotation, alternating crops (including nitrogen-fixing legumes), restores nutrients and breaks pest and disease cycles;
• Reduced or no tillage and keeping ground cover protect soil from erosion and retain organic matter;
• Integrated pest management combines biological control, resistant varieties and targeted pesticide use to cut chemical inputs;
• Efficient irrigation (such as drip systems) reduces water use and salinisation;
• Organic farming avoids synthetic fertilisers and pesticides;
• Reducing food waste lowers the production needed in the first place.

These approaches link food directly to the soil and water resources of Earth's Resources and to the carrying-capacity idea in global challenges.

Examples in context

Example 1. Crop rotation and the nitrogen cycle. Including a clover or legume year in a rotation lets nitrogen-fixing bacteria in the roots replenish soil nitrogen, reducing the fertiliser needed for the following cereal crop. It links soil fertility and the nitrogen cycle to a practical, long-standing sustainable farming method.

Example 2. Food waste in supply chains. A large share of food produced is lost or wasted between farm and fork. Because every wasted tonne represents wasted land, water, energy and emissions, cutting waste is one of the most effective ways to feed more people with less environmental impact.

Try this

Q1. Name two ways intensive agriculture can degrade soil. [2 marks]

• Cue. Any two of: erosion from ploughing, nutrient loss from monoculture, compaction by machinery, salinisation from over-irrigation.

Q2. State one sustainable farming practice and explain how it protects the soil. [2 marks]

• Cue. Crop rotation restores nutrients and breaks pest cycles; or reduced tillage and ground cover prevent erosion.