Water holding capacity, wood

Vapor Pressure Deficit. The water-holding capacity of saturated wood changes when it cools below the freezing point, with lowering of the fiber-saturation point (ii). When saturated wood is frozen, the vapor pressure of ice, is lower at the same temperature than the vapor pressure of supercooled water, e, bound to internal surfaces. The resulting saturated vapor pressure diflFerence between the ice and the supercooled water is given by and may be referred to as a vapor pressure deficit (VPD). 

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