2.4 Data calculations and statistics
The formula for calculating phytolith and PhytOC contents in plant species were as follows:
phytolith content (g kg-1) = phytolith weight (g) / dry biomass (kg) [1]
PhytOC content (g kg-1) = PhytOC weight (g) / dry biomass (kg) [2]
The community weighted mean contents of phytolith (PhytolithCWM) and phytOC (PhytOCCWM) were also calculated using biomass as weight:
phytolithCWM (g kg-1)=∑i phytolith contenti (g kg-1)×biomassi (%) [3]
PhytOCCWM (g kg-1)=∑i PhytOC contenti(gkg-1)×biomassi (%) [4]
where i enumerates each species.
PhytOC stock (kg ha-1)= PhytOCCWM (g kg-1)×biomass (kg ha-1)×10-3 [5]
PhytOC production flux (kg ha-1yr-1) = PhytOCCWM(gkg-1)×NPP (kg ha-1yr-1)×10-3 [6]
One-way ANOVA and Duncan’s multiple range test were performed to examine the difference in phytolith and PhytOC contents among different parts of plant species. SPSS 20.0 was used for all the statistics and Sigma Plot 12.0 was used for figures.