AGR 2320 Lecture Notes - Lecture 17: Loam, Water Retention Curve, Permanent Wilting Point

• School: University of Guelph
• Department: Agriculture
• Course: AGR 2320
• Professor: John Lauzon

Document Summary

Agr 2320 lecture 17 water retention. O osmotic : electrical conductivity: how diff are ions on 1 side of the membrane from another. A water sealed pipe with a ceramic cup. Describes the functional relation between water content & matric potential. As matric potential decreases (pores losing water), water content also decreases. 0 matric potential: soil is completely saturated: no more pore space, 1 bar = -100 cm of matric potential. Wilting point (wp): soil water content at which plants will become permanently wilted: approximately m= -15 bar. Available water (aw): the proportion of soil water that can be readily absorbed by plants: water released between field capacity and wilting point. Effects of increasing organic matter content on the water retention curve. Small increase in water content at wp (wilting point) Larger increase in water content at fc (field capacity) Solar distillation of water from soil & plant materials.