Fig. 3: Three pairs of feedback simulations versus null simulations.
From: Positive feedbacks and alternative stable states in forest leaf types
Histograms in A–D represent the relative evergreen abundance within 1000 simulated forest plots after 2000 years. The color scale represents the percentage of evergreen forest within a plot (red, 100% deciduous; blue, 100% evergreen). A, Outcome of null demographic simulations with uniform initialization, from growth, recruitment, and mortality models fit without con-phenological feedback predictors. The inset in (A) shows the initial uniform distribution of relative evergreen abundance across the 1000 plots. The uniform distribution shifts to evergreen-dominated forests after 2000 years. B, Outcome of demographic simulations with uniform initialization from demographic models fit with con-phenological predictors. Most plots are dominated by either of the two leaf phenology strategies (bimodal distribution). C Outcome of null demographic simulations with bimodal initialization, from growth, recruitment, and mortality models fit without con-phenological feedback predictors. The inset in panel C shows the initial bimodal distribution of forest composition. As in panel A, the bimodal distribution shifts to evergreen-dominated forests after 2000 years. D Outcome of demographic simulations with bimodal initialization from demographic models fit with con-phenological predictors. Most plots are dominated by either of the two leaf phenology strategies. E, F Hysteresis simulations along mean annual temperature gradients, where 80% of forest plots (800 of 1000) were initially dominated by evergreen trees (EV, blue line) or deciduous trees (DE, red line). Demographic simulations were run either without feedback predictors (E) or with feedback predictors (F). Shaded regions represent the 95% CI of the mean relative abundance of evergreen trees across each set of simulations (n = 1000). Source data are provided as a Source Data file.
