Advanced Placement (AP) Human Geography Practice Exam

What is desertification primarily caused by?

1. Climate change

2. Urbanization

3. Overgrazing and soil erosion

4. Natural disasters

The correct answer is: Overgrazing and soil erosion

Desertification primarily occurs due to overgrazing and soil erosion, which disrupt the soil's structure and health. This process involves the depletion of vegetative cover, making the land more vulnerable to erosion from wind and water. When livestock overgraze specific areas, it reduces the plant cover that protects the soil, leading to a loss of soil nutrients and structure. Without plants to anchor the soil, it becomes easier for natural elements to wash or blow the soil away, exacerbating land degradation and ultimately transforming once-productive land into desert-like conditions. While factors like climate change and natural disasters can contribute to desertification, the immediate and direct drivers of this phenomenon stem from human activities, particularly unsustainable agricultural practices. Urbanization, on the other hand, primarily influences land use and may affect local ecosystems, but it does not directly cause desertification as overgrazing and poor soil management do. Thus, understanding the primary cause of desertification highlights the impact that agricultural practices have on land sustainability and the environment.