Which of the following is NOT a soil factor listed?

• A. Infiltration rates
• B. Water-holding capacity
• C. Salinity
• D. Evapotranspiration

Answer: (D)

Soil factors refer to properties of the soil that influence how water moves and is stored in the root zone. Infiltration rate describes how quickly water enters the soil, shaping how soon the soil becomes saturated after irrigation. Water-holding capacity indicates how much water remains available to plants between irrigation events. Salinity reflects the concentration of soluble salts in the soil, which affects plant water uptake and osmotic stress. Evapotranspiration, on the other hand, is not a soil property; it measures the total water lost to the atmosphere from both evaporation and plant transpiration, driven by weather and crop demand. It informs irrigation scheduling but isn’t a soil factor itself.