Effects of environmental heterogeneity on plant species richness (Hypothesis 3)
Results showed that light heterogeneity had a positive effect on plant species richness (p = 0.005, r² = 0.57, fig. 6). The heterogeneity of potassium correlated slightly positively with increasing plant species richness, but this relationship was not statistically significant when outliers were removed (excluding all values above 1.5 * interquartile range).