GEOB 102 Lecture Notes - Lecture 21: Soil Texture, Permanent Wilting Point, Field Capacity

• School: UBC
• Department: Geographical Biogeosciences
• Course: GEOB 102
• Professor: Greg Henry

Document Summary

Outputs: actual evapotranspiraion(ea, change in soil storage ( s) Soil water recharge (+g: fills available pore spaces in soil. Water removed by gravity when soil is saturated: capillary water. Water that resists gravity by clinging" to soil paricles via capillary tension (force: storage capacity (ield capacity) Amount of capillary water, available for plant use. Depends on soil texture and organic mater (om) Highest storage capacity = ine texture + abundant om: wiling point (wp) Below wp = high capillary tension =water not available. Fine texture = high capillary tension = high wp. Largest diference between the storage capacity line and the wiling point line. Rate of water vapor return to the atmosphere from the ground and plant cover. Potenial evapotranspiraion(ep: ideal rate that would occur if complete plant cover and unlimited water(soil at field. Represents energy status: rarely achieved, used as a comparison. Actual evapotranspiraion(ea: rate that actually occurs given availability of biologically usable energy and water.