Formulate an algebraic expression that describes all of the observations made on different flow systems. Design new experiments on which to test the expression developed. In exercise 1, matric potentials were always greater than or equal to zero. Here they are allowed to become negative and the impact of that upon flow is observed. Soil water content decreases as matric potential becomes more and more negative.
Hydraulic conductivity decreases with decreasing matric potential in unsaturated soils.
Total and matric potentials are generally not linearly related to position in the soil. Users are challenged to explain why this occurs based on discoveries made already. Water does not always move from high water contents to lower water contents. Water content within a soil need not be uniform when no flow occurs. Hydraulic properties often change with depth.