Field capacity - water content at which gravity drainage of water ceases. Wilting point - water content at which water is not available for plant root to withdraw. Filed capacity is a function of time and wilting point is a function of plants. As R decreases, h increases. Soil pres can be treated as capillary tubes.
Water rises above water table due to surface tension.
Therefore, the height of capillary fringe varies with soil types and grain sizes. See Fig 6.9 on page 189 for detail. Confined between 2 aquitards. Water is recharged from recharge area. Water table is the upper boundary.