Which process is primarily enhanced by earthworm activity?

Earthworm activity plays a crucial role in enhancing nutrient cycling within the soil ecosystem. As earthworms burrow through the soil, they break down organic matter such as dead leaves and plant material, facilitating its conversion into forms that are accessible to plants. This process not only enriches the soil with essential nutrients but also improves soil structure, aeration, and moisture retention.

The presence of earthworms leads to the production of humus, a rich organic substance that binds soil particles together, enhancing fertility. Furthermore, earthworms excrete nutrient-rich casts, which contribute to the nutrient content of the soil, promoting healthier plant growth.

While other options might suggest negative impacts on soil health, they do not align with the beneficial role that earthworms play in fostering a dynamic nutrient cycling process critical for sustaining productive and healthy soils.