soil water energy concept

Group C4

Due to gravitational forces

According to concentration gradient

Water moves from high water potential to low water potential

Wet soil to dry soil

Wet soil

◦ High amount of pore space

◦ High water potential

Dry soil

◦ Low amount of pore space

◦ Low water potential

Gravimetric potential◦ Helps water to move by gravity

Pressure potential◦ Submerged potential

◦ Matrix potential

Osmotic potential◦ Moves water according to the dissolving of particles

Capillary force◦ Adhesion and cohesion

Adsorptive forces

Osmotic forces

Capillary force

◦Due to adhesive and cohesive powers

Adhesion

Tendency of dissimilar particles or surfaces to cling to one another

Cohesion

Tendency of similar or identical particles to cling to one another

◦Due to properties of water, it moves through the soil

◦ Small pores in the soil can be assumed as capillary tubes

◦ r α 1/h

◦ Large pore space – low water movement

◦ Small pore space – high water movement

Water binds strongly to mineral surfaces due to polarity in molecules

This results in forming a thin water film

Water moving between roots and soil

Through the cell membranes of root hairs, which are semi permiable

According to a water potential gradient

Thank you!