Water moves from areas of high water potential to low water potential through soils due to gravity and concentration gradients. Wet soil has high water potential due to large pore spaces, while dry soil has low water potential with small pore spaces. Water movement is driven by gravimetric, pressure, osmotic, and capillary potentials, with capillary movement occurring through small pores via adhesion and cohesion of water molecules.
2. Due to gravitational forces
According to concentration gradient
3. 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
4. Gravimetric potential
◦ Helps water to move by gravity
Pressure potential
◦ Submerged potential
◦ Matrix potential
Osmotic potential
◦ Moves water according to the dissolving of particles
6. Capillary force
◦ Adhesion and cohesion
Adsorptive forces
Osmotic forces
10. ◦ 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
11. Water binds strongly to mineral surfaces due
to polarity in molecules
This results in forming a thin water film
12. Water moving between roots and soil
Through the cell membranes of root hairs,
which are semi permiable
According to a water potential gradient