Figures & data
FIGURE 1. Schematic of Marion Island indicating the location of the study sites (transects - straight lines; quadrats – squares) and the 500 and 1000 m a.s.l. contour lines. The maximum altitude (in m a.s.l.) of each transect and the mean altitude of each quadrat are also indicated
FIGURE 2. Frequency distributions for Azorella selago cushion plants across all quadrats of a) maximum diameter (n = 738), b) height (n = 738), c) growth rate (n = 527), d) estimated plant age (n = 738, using mean growth rate for each quadrat to estimate age)
FIGURE 3. Mean (± S.E.) a) maximum diameter and b) growth rate of Azorella selago plants sampled at each site. Number above whiskers indicates sample size. Sites not sharing a letter (below whiskers) were significantly different at P < 0.05
FIGURE 4. Relationships between Azorella selago plant maximum diameter and distance to its two nearest neighbors for each quadrat (simple linear regression lines fitted for illustration, see for full model results)
TABLE 1 Coefficient of variation of growth rate (% CV) (across all size classes), and the results of the regression of CV against plant height classes for each site. Age (years) estimates for plants at each site also provided. Minimum ages not estimated for plants within transects
TABLE 2 Proportion of variation in plant diameter, height and growth rate attributable to biotic and spatial variables. Standardized coefficient estimates are provided for the biotic variables and altitude to indicate the direction and magnitude of effects
TABLE 3 Simulated ages (mean simulated age and three measures of variability around that mean age, i.e. estimate of accuracy) for three idealized plant heights using measured growth rate data from the six study sites
