Which factor is listed as influencing river discharge by supporting plant life and water uptake from the land?

Which factor is listed as influencing river discharge by supporting plant life and water uptake from the land?

• A. Vegetation
• B. Urban development
• C. Ice cover
• D. Desert soils

Answer: (A)

Plants regulate how water moves across the land. Vegetation intercepts rainfall, slows down surface runoff, and creates pathways in the soil through root systems that promote infiltration. The roots take up water from the soil and, through transpiration, return some of it to the atmosphere. This combination means less water immediately reaches rivers after a rain event, and more water can seep into the ground to recharge groundwater, which can sustain river flow during drier periods. So vegetation directly influences river discharge by supporting plant life and the land’s water uptake.

Other factors change discharge in different ways—for example, urban development tends to increase peak runoff, ice cover can reduce flow in winter, and desert soils with little vegetation often lead to different infiltration and runoff patterns.