Geo Reviewer Surface Water Practice Exam

The capillary fringe is defined as the zone above the water table where water is held in the soil by capillary action. This characteristic implies that water is retained in the pore spaces of the soil and is held tightly to soil particles. In this zone, water is not freely flowing like it would be in saturated conditions; rather, it exists in a state that allows it to be absorbed by plant roots but does not move easily through the soil, leading to a relatively high moisture content compared to other zones. This ability to hold water tightly is essential for plants and soil ecology, particularly in supporting vegetation during dry times or periods where groundwater may not be easily accessible. The other options do not accurately describe the properties or function of the capillary fringe.