Figures & data
FIGURE 1. Percent cover for Peltigera aphthosa and P. polydactyla in control (C), phosphorus (P), and nitrogen (N) treatments on acidic and non-acidic tundra. Quadrats were averaged within plots, and data presented are plot means for each treatment, with standard error bars (n = 4 for acidic tundra or 3 for non-acidic tundra)
FIGURE 2. Acetylene reduction rates for Peltigera aphthosa and P. polydactyla in control (C) and phosphorus (P) treatments on acidic and non-acidic tundra. Values are means with standard error bars (n = 3)
FIGURE 3. Nitrogen concentrations in Peltigera aphthosa and P. polydactyla from control (C) and phosphorus (P) treatments on acidic and non-acidic tundra. Values are means with standard error bars (n = 3)
FIGURE 4. Percent cover of Peltigera aphthosa and P. polydactyla on acidic and non-acidic tundra. Values are means with standard error bars (n = 80)
FIGURE 5. Acetylene reduction rates for Peltigera aphthosa and P. polydactyla on acidic and non-acidic tundra. Values are means of three dates with standard error bars (n = 18 or 17 for P. aphthosa on non-acidic tundra)
TABLE 1 Three-way ANOVA comparing abundance of Peltigera aphthosa and P. polydactyla between sites, and among control (C), nitrogen (N), and phosphorus (P) treatments, with Tukey's HSD posthoc test. Three-way ANOVA comparing N2-fixation rates per unit area and per unit mass between P. aphthosa and P. polydactyla, acidic and non-acidic tundra, and control and P treatments
TABLE 2 Two-way ANOVA comparing abundance of Peltigera aphthosa and P. polydactyla between moist acidic and moist non-acidic tundra. Three-way ANOVA comparing N2-fixation rates per unit area and per unit mass between P. aphthosa and P. polydactyla, between moist acidic and moist non-acidic tundra, and among the three sampling dates
TABLE 3 Three-way ANOVA comparing lichen N concentration between Peltigera aphthosa and P. polydactyla and between the control (C) and phosphorus (P) treatments at the acidic and non-acidic sites
