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

What is a significant consequence of modern farming methods like ploughing?

1. It increases crop yields significantly

2. It damages earthworms, leading to soil compaction

3. It improves soil aeration

4. It enhances nutrient availability in the soil

The correct answer is: It damages earthworms, leading to soil compaction

Modern farming methods, such as ploughing, often result in damage to earthworm populations, which is a significant consequence of these practices. Earthworms play a crucial role in maintaining healthy soil structure and fertility. They help with soil aeration, nutrient cycling, and organic matter decomposition. When soil is heavily disturbed by ploughing, the habitat for these organisms is disrupted, which can lead to a decline in their populations. The reduction of earthworms in the soil means less natural aeration, as they normally create burrows that allow air and water to penetrate the soil more effectively. Additionally, their absence can lead to issues like soil compaction, which negatively affects root development and reduces the soil's overall ability to retain moisture and nutrients. This consequence highlights the delicate balance of soil ecosystems and how modern agricultural practices can impact them significantly.