What is the main reason removing trees from a tropical rainforest can lead to soil erosion?

The main reason removing trees from a tropical rainforest can lead to soil erosion is that the removal of trees results in fewer roots to hold the soil in place. Trees and their root systems play a crucial role in stabilizing the soil. The roots of trees penetrate the soil, creating a network that binds the soil particles together. This anchorage helps to prevent soil from washing away during heavy rains, a common occurrence in tropical regions.

When trees are cut down, this network of roots is disrupted. Without the roots to stabilize the soil, erosion can occur more easily, particularly during wet weather when rainfall can quickly wash away unanchored soil. Additionally, the absence of trees can lead to increased runoff, as there are fewer barriers to slow down rainfall and allow it to infiltrate the ground, further contributing to soil erosion.

While the other options touch on relevant concepts, they do not directly address the immediate impact of tree roots on soil stability in the context of erosion as effectively as the chosen answer. For example, while solar radiation and insect populations may play roles in the ecosystem's health, they do not specifically explain the mechanism of soil erosion caused by the lack of tree roots.