Figure 1.
Location of the sampling sites on the eastern slope of Gongga Mountain, SW China.
BLF: broad-leaf forest; BLF-SDC: broad-leaf and dark coniferous mixed forest; SDC: subalpine dark coniferous forest; TL: timberline (forest coverage<10%); ASG: alpine shrub-grass; and AM: alpine meadows.
Table 1.
Soil and vegetation properties in the six vegetation zones.
Figure 2.
MBP concentrations in the vegetation zones and the relationships between MBP and environmental factors.
MBP concentrations were measured in three plots in each vegetation zone (n = 3). The solid line corresponds to the fitted curve of the quadratic polynomial model in Figure (a). A linear regression (n = 18) is shown in Figures (b), (c) and (d).
Figure 3.
Resin-P(a), NaHCO3-P(b), NaOH-P(c) and HCl-P(d) concentrations with altitude.
Three plots were sampled in each vegetation zone (n = 3). Vegetation zones along the altitudinal gradient occurred in the following order: BLF, BLF-SDC, SDC, TL, ASG and AM.
Table 2.
The results for the multiple linear regressiona.
Figure 4.
Microbial C:P (a) and N:P (b) ratios in the six vegetation zones.
These ratios were calculated on a mass basis (and converted to P based on PO43−). The same letters indicate no significant difference (at p >0.05). The error bar represents the standard error (n = 3).
Figure 5.
Relationships between MBP and phosphorus speciation on Mount Gongga.
(a) MBP vs. Resin-P; (b) MBP vs. NaHCO3-P; (c) MBP vs. NaOH-P; and (d) MBP vs. HCl-P. The lines represent linear model fits.
Table 3.
Microbial biomass C, N and P ratios (mass ratios) compared with the reference ratios (mass ratios) proposed by Cleveland and Liptzin.