Human Activity and Water Sheds

A student's model of an area near a city depicts many activities that affect the quality of the water in the area.

How does the agricultural activity most likely affect the surface water of the area?

• Excess crop fertilizer is carried by runoff into the river, causing excess growth of water plants.

• Excess drop material accumulates in the riverbanks, slowing the movement of the river water.

• Crops reduce erosion, increasing the amount of soil entering the river.

• Crops absorb pure water from soil, causing the remaing water to contain more salt.

A student drew the model below to represent a part of a watershed and some human activities that affect the watershed.

How do the industrial, agricultural, and residential activities of humans most likely affect the groundwater in the area?

• The activities prevent most of the water from evaporating into the atmosphere.

• Pollutants from the activities percolate through the soil and enter the water table.

• The activities replace the groundwater used.

• All of the above.

A student sets up the investigation shown.

The movement of colored water through the gravel best models -

• condensation of water vapor

• surface runoff of precipitation

• conservation of water

• pollution of groundwater