Which of the following processes would benefit soil fertility most?

Maintaining a balance of moisture in the soil is crucial for enhancing soil fertility. Adequate moisture levels allow for optimal biological activity, which is essential for nutrient cycling and the breakdown of organic matter. Healthy soil microbiomes thrive in well-balanced moisture conditions, leading to improved nutrient availability for plants.

When moisture levels are balanced, plants can absorb nutrients effectively from the soil, which promotes their growth and health. This balance helps prevent issues such as waterlogging, which can suffocate roots and inhibit plant growth, as well as drought conditions that stress plants and limit nutrient uptake.

In contrast, frequent leaching during heavy rains can wash away essential nutrients from the soil, negatively impacting its fertility. Decreasing organic matter content reduces the soil's ability to retain moisture and nutrients, leading to poorer soil health. Encouraging calcification in wet conditions can also be detrimental, as it may result in an accumulation of salts that can harm plant life. Thus, maintaining moisture balance is the most beneficial process for soil fertility.