What is the main consequence of excessive drainage on soil nutrients?

Excessive drainage of soil primarily leads to nutrient loss. When soil is drained excessively, water is removed from the soil profile more rapidly than plants can use it. This results in leaching, where crucial nutrients such as nitrogen, potassium, and magnesium are washed away from the root zone. These nutrients are vital for plant growth, and their depletion can significantly reduce soil fertility.

In addition to nutrient loss, excessive drainage can disturb the balance of the soil ecosystem, affecting not only the availability of nutrients but also the microbial activity essential for nutrient cycling. Consequently, maintaining proper moisture levels in the soil is vital for nutrient retention and overall soil health. By contrast, options like the accumulation of salts, retention of moisture, or improved soil structure do not accurately represent the primary consequence of excessive drainage, making nutrient loss the most relevant outcome.