Which of the following statements best describes leaching?

Leaching is a natural process that occurs when water, typically from rainfall, percolates through the soil and carries away dissolved nutrients and minerals. This movement helps to transport essential elements but can also cause a depletion of these nutrients from the soil, particularly in regions with high rainfall. As water filters through the soil layers, it can wash away important nutrients such as nitrates and potassium, leading to decreased fertility in the upper soil layers over time.

Understanding leaching is vital for agricultural practices and soil management. If nutrients are constantly being removed without proper replenishment, crops may struggle to grow effectively, leading to lower agricultural yields. The other options involve processes that either add to soil health or retain nutrients, making them less applicable in the context of leaching.