Environmental Science · Year 13 · Biological Resources and Conservation · 3.º Período

Agriculture and Food Security

Students will analyse the environmental impacts of intensive farming systems and explore sustainable agricultural practices. The focus will be on soil conservation and pest management.

TL;DR:Agriculture is a primary driver of environmental change, and this topic examines the balance between food security and ecological health. Students analyse intensive farming methods, including the use of synthetic fertilisers, pesticides, and heavy machinery, and their roles in soil degradation and biodiversity loss. The topic also explores sustainable alternatives like Integrated Pest Management (IPM), organic farming, and conservation tillage, aligning with AQA standards on agriculture and biodiversity.

• National Curriculum Attainment Targets
• AQA A-level Environmental Science, 3.5.1 Agriculture
• AQA A-level Environmental Science, 3.1.2 Conservation of biodiversity

About This Topic

Agriculture is a primary driver of environmental change, and this topic examines the balance between food security and ecological health. Students analyse intensive farming methods, including the use of synthetic fertilisers, pesticides, and heavy machinery, and their roles in soil degradation and biodiversity loss. The topic also explores sustainable alternatives like Integrated Pest Management (IPM), organic farming, and conservation tillage, aligning with AQA standards on agriculture and biodiversity.

Students must understand the science of soil, its structure, nutrient cycles, and the importance of the soil biota. This knowledge is essential for evaluating how different farming systems impact long-term food security. This topic comes alive when students can physically model the patterns of soil erosion and debate the ethics of intensive versus extensive farming.

Key Questions

1. How does intensive agriculture degrade soil structure?
2. What are the ecological consequences of pesticide use?
3. How can integrated pest management improve food security?

Watch Out for These Misconceptions

Common Misconception

Organic farming uses no pesticides.

What to Teach Instead

Organic farmers can use certain naturally derived pesticides, though they prioritise biological and mechanical controls. Peer research into organic standards helps students understand the nuances of different certification schemes.

Common Misconception

Hydroponics is always more sustainable than soil-based farming.

What to Teach Instead

While it saves water and space, hydroponics is often very energy-intensive due to lighting and climate control. A collaborative investigation into the 'energy footprint' of different systems helps students see the trade-offs.

Active Learning Ideas

Simulation Game

The Pest Management Game

Students act as farmers managing a crop. They must choose between chemical pesticides, biological controls, or IPM. They face 'random events' like pest resistance or weather changes to see which strategy is most resilient.

45 min·Small Groups

Gallery Walk

Sustainable Farming Techniques

Stations feature different techniques: hydroponics, agroforestry, and permaculture. Students move between stations to identify how each technique addresses a specific environmental issue, such as water scarcity or soil erosion.

40 min·Small Groups

Think-Pair-Share

The Meat Dilemma

Students individually calculate the energy efficiency of producing 1kg of beef versus 1kg of wheat. They pair up to discuss the environmental implications of 'eating lower on the food chain' before sharing with the class.

20 min·Pairs

Frequently Asked Questions

What is Integrated Pest Management (IPM)?

IPM is an ecosystem-based strategy that focuses on long-term prevention of pests through a combination of techniques such as biological control, habitat manipulation, and the use of resistant varieties. Pesticides are used only as a last resort.

How does intensive ploughing lead to soil degradation?

Ploughing breaks down soil structure, increases the rate of organic matter decomposition, and leaves the soil surface exposed to wind and water erosion. Over time, this leads to a loss of fertility and reduced water-holding capacity.

What is the 'Green Revolution'?

The Green Revolution refers to a period of rapid agricultural transformation in the mid-20th century, characterised by the development of high-yielding varieties of cereal grains, expansion of irrigation, and increased use of synthetic fertilisers and pesticides.

How can active learning help students understand agriculture?

Active learning, such as a pest management simulation, allows students to see the consequences of their decisions in 'real-time'. By experiencing how pests develop resistance to chemicals, they gain a deeper, more practical understanding of ecological principles than they would from a textbook alone.