Fig. 1: Bimodal patterns of forest types at the continental and global scale.
From: Positive feedbacks and alternative stable states in forest leaf types
A The spatial distribution of 45,276 forest inventory sites from the FIA was used for the continental analysis. The continuous color scale represents the relative abundance of evergreen trees within a plot (red = 100% deciduous; blue = 100% evergreen). B Histogram of the observed plot-level evergreen percentage across the mainland US. The black dots and error bars show the medians and 2.5–97.5% quantiles of the null model predictions driven by environmental filtering (zero adjusted Poisson distribution). C Spearman’s rank correlation coefficient between evergreen abundance and deciduous abundance in the observed data (red bar) versus the simulated results of the null model (black histogram). D The location of 815,578 forest plots from the global GFBI database. E and F are the same as panels B, and C, but for the global data. Hartigan’s dip test52 showed significant multi-modality (here is bimodality) in the observed values in panels B (n = 45,276, one-sided p-value < 0.001) and E (n = 815,578, one-sided p-value < 0.001). Source data are provided as a Source Data file.
