OCR General Certificate of Secondary Education (GCSE) Biology Practice Exam

Why is the direct drilling method considered advantageous over ploughing?

1. It reduces the need for water

2. It prevents damage to earthworms, maintaining soil fertility

3. It increases crop rotation efficiency

4. It enhances pest control

The correct answer is: It prevents damage to earthworms, maintaining soil fertility

The direct drilling method is considered advantageous over ploughing primarily because it prevents damage to earthworms, which play a crucial role in maintaining soil fertility. When soil is ploughed, the activity can disrupt the habitat of earthworms, negatively affecting their population and the essential functions they provide in the soil ecosystem. Earthworms contribute to soil aeration, organic matter decomposition, and nutrient recycling, all of which enhance soil health and fertility. By using direct drilling, farmers are able to plant seeds directly into undisturbed soil, thus preserving the structure of the soil and protecting the earthworm population. This not only supports long-term soil fertility but also promotes healthier crop yields over time. In contrast, while the other options might have their own merits in specific contexts of agricultural practices, they do not directly relate to the impact that direct drilling has on earthworm populations and the resulting benefits to soil fertility.