Tuesday, February 8, 2000

1
At equilibrium (after free drainage but no
evapotrans-piration), total potential head will
be the same throughout the soil. z
h Tens 1 80 -80 Tens 2 20 -20 W.
table 0 0
soil surface
z 100 cm
80 cm
1
1 meter
2
20 cm
z 0 h 0
water table
2
With evapotrans-piration), total potential head
will be lower nearer the surface. z
h Tens 1 80 -95 Tens 2 20 -25 W.
table 0 0
soil surface
z 100 cm
80 cm
1
1 meter
2
20 cm
z 0 h 0
water table
3
rain
With steady rainfall, there will be matric
potentials closer to zero and downward
movement. z h Tens 1 80
-10 Tens 2 20 -5 W. table 0 0
soil surface
z 100 cm
80 cm
1
1 meter
2
20 cm
z 0 h 0
water table