specific yield

Specific yield refers to the amount of water that can be extracted from a certain volume of soil or rock material. It is expressed as a percentage or a fraction, indicating how much of the total water in the material can actually be drained or used. For example, if soil has a specific yield of 20%, this means that 20% of the water stored in that soil can be removed, while the rest remains trapped. This concept is crucial in fields like hydrology and agriculture, as it helps determine available water resources for irrigation and groundwater management.