Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.07.22.216226v1?rss=1 Authors: Pellegrini, A., Refsland, T., Averill, C., Terrer, C., Staver, C., Brockway, D., Caprio, A., Clatterbuck, W., Coetsee, C., Haywood, J., Hobbie, S., Hoffmann, W., Kush, J., Lewis, T., Moser, W. K., Overby, S., Patterson, W., Peay, K. G., Reich, P., Ryan, C., Sword, M., Scharenbroch, B., Schoennagel, T., Smith, G., Stephan, K., Swanston, C., Turner, M., Varner, M., Jackson, R. B. Abstract: Global change has shifted fire regimes, but the long-term consequences for ecosystems are uncertain because of variability in environmental conditions, fire types, and plant composition. We tested how fire-frequency manipulations of 16-64 years affect tree communities and traits using 374 plots from 29 sites on four continents. More frequently burned plots had lower tree basal area and stem densities that compounded over multiple decades: average fire frequencies reduced basal area by only 4% after 16 years but 57% after 64 years, relative to unburned plots. Fire had the largest effects on basal area in sites with strong seasonality and in savanna ecosystems. Tree functional-trait data revealed that frequently burned plots had tree communities dominated by species with low biomass nitrogen and phosphorus content and with more efficient nitrogen acquisition through ectomycorrhizal symbioses. Our data provide broad experimental evidence that altered fire regimes will shift tree community basal area, stem density, and functional composition in a diversity of settings. The responses of tree communities compounded over multiple decades, suggesting short-term observations may substantially underestimate the sensitivity of ecosystems to altered fire regimes. Copy rights belong to original authors. Visit the link for more info