Water can move through the soil-plant-atmosphere continuum, only if water potential along that path
Decreases
Increases
Remains unchanged
Fluctuates rapidly in either direction
Water can move through the soil-plant-atmosphere continuum only if the water potential along that path is decreasing.
Water potential is a measure of the potential energy of water molecules in a system and determines the direction and rate of water movement. Water moves from areas of higher water potential to areas of lower water potential.
In the soil-plant-atmosphere continuum, water moves from the soil, through the plant roots, up the stem, and finally exits through the leaves into the atmosphere via transpiration. This movement is driven by differences in water potential along this pathway.
Water potential decreases along the soil-plant-atmosphere continuum. In the soil, water potential is usually higher because of the presence of water and solutes. As water is taken up by plant roots and transported through the plant, water potential gradually decreases. This decrease in water potential is essential for the movement of water from the roots to the leaves.
The decrease in water potential creates a gradient that allows water to move upward, against gravity, through the plant's vascular system. Transpiration from the leaves creates a negative pressure or tension that pulls water from the roots upward. This negative pressure lowers the water potential in the leaves, promoting the movement of water through the plant and eventually into the atmosphere.
Therefore, for water to move through the soil-plant-atmosphere continuum, there needs to be a decrease in water potential along the pathway, enabling the movement of water from areas of higher potential to areas of lower potential. Hence, the correct answer is option 1