Advanced Placement (AP) Human Geography Practice Exam

What can contribute to soil erosion?

1. Increased vegetation

2. Overgrazing

3. Reforestation practices

4. Controlled agricultural techniques

The correct answer is: Overgrazing

Soil erosion is primarily influenced by factors that disturb the soil and remove protective vegetation. Overgrazing occurs when livestock graze excessively on vegetation, preventing plants from regenerating. This loss of vegetation exposes the soil to wind and water erosion, leading to significant degradation of the land. Without adequate plant cover, the soil structure deteriorates, making it more vulnerable to being washed or blown away. In contrast, increased vegetation, reforestation practices, and controlled agricultural techniques contribute positively to soil retention. Increased vegetation serves as a protective layer, stabilizing the soil with roots that hold it in place and preventing erosion. Reforestation helps restore forest cover, which enhances soil quality and reduces runoff. Controlled agricultural techniques often include practices like contour plowing and crop rotation that minimize disruption to the soil, thereby protecting against erosion and maintaining its health.