3.4 Community-weighted mean contents of phytolith and PhytOC
The community-weight mean phytolith content
(phytolithCWM) and PhytOC content
(PhytOCCWM) in the above- and belowground plant biomass
were calculated. As plant belowground biomass was measured at species,
not community level, the relative belowground biomass of each species
was estimated using the measured relative aboveground biomass (AGB%)
and the shoot/root ratio (A/B) of each species, and used to calculate
the community weighted mean phytolith content of belowground biomass.
The phytolithCWM was 16.68, 17.94 and 15.85 g
kg-1 respectively in the aboveground biomass of desert
steppe, dry typical steppe and wet typical steppe, no significant
difference being detected among the three steppe types
(P >0.05); the PhytOCCWM in the
belowground biomass was neither significantly different among the three
steppe types (P >0.05), being 86.44, 58.73 and 76.94
g kg-1 for the desert steppe, dry typical steppe and
wet typical steppe, respectively (Fig.3). The PhytOCCWMwas 0.68 g kg-1 in the aboveground biomass of desert
steppe, which was higher than in that of dry typical steppe (0.48 g
kg-1) or wet typical steppe (0.59 g
kg-1). The PhytOCCWM in the
belowground biomass was 1.11, 0.72 and 1.02 g kg-1respectively in desert steppe, dry typical steppe and wet typical
steppe, with no significant difference among these steppes
(P >0.05) (Fig.3).