Determination of tree stem water content
To examine the volume and use of stored plant water, we determined the
relative wood moisture content (WMC). For this, two horizontal wooden
cores (1” x 0.5” cylinder) were extracted at breast height from 16 trees
with a perforating puncher at the opposite sides of the trunk (four
cores per species/plot) at the end of each of five ecohydrological
periods (depletion: February 2013 and April 2014; recovery: May 2013;
wet: October 2013 and 2014) (n=64). In this case, the number of samples
was small to reduce the damage of sap conduction through the trunk.
Relative wood moisture content (WMC) was calculated by using the fresh
weight (Wfresh) and dry weight (Wdry) (48 hours at 70ºC) of each sample:
WMC = (Wfresh – Wdry) / Wdry x 100%