What is the definition of leaching in environmental science?

Leaching in environmental science refers to the process by which soluble substances, such as nutrients or contaminants, are dissolved and carried away from the soil into groundwater. This occurs when water, often from precipitation or irrigation, percolates through the soil, effectively washing away certain elements. This process can significantly impact soil fertility and groundwater quality, as it may result in the loss of essential nutrients like nitrates and phosphorus from the soil, or the transport of pollutants into water supplies. Understanding leaching is crucial for managing agricultural practices and protecting water resources, as it influences both the ecological balance and human health.