Infiltration is best described as what?

• A. Water leaving soil
• B. Water evap
• C. Water stored at surface
• D. Water entering soil

Answer: (D)

Infiltration is water entering soil from the surface. When rain or irrigation wets the ground, some of that water soaks in, filling pore spaces and moving downward into the root zone and deeper layers. This process is influenced by soil texture and structure, moisture level, compaction, organic matter, and vegetation cover, and it helps recharge soil moisture and reduce surface runoff. It differs from evaporation (water moving from soil or surface to the air), from water stored at the surface (water that stays on top rather than entering), and from water leaving the soil (through drainage or runoff). That's why the description “water entering soil” best captures infiltration.