Biomass partitioning and root morphology of savanna trees across a water gradient (pages 1113–1121)
Kyle W. Tomlinson, Frank J. Sterck, Frans Bongers, Dulce A. da Silva, Eduardo R. M. Barbosa, David Ward, Freek T. Bakker, Martijn van Kaauwen, Herbert H. T. Prins, Steven de Bie and Frank van Langevelde
Article first published online: 12 APR 2012 | DOI: 10.1111/j.1365-2745.2012.01975.x
Water stress has not selected biomass partitioning differences among seedlings of tree species from semi-arid (open bars) and humid (filled bars) savannas from three continents. High allocation to roots (RMF) and low allocation to stems (SMF) is associated with species of humid environments where fire is more frequent, indicating that selection by fire pressure supersedes any selection in response to water constraints. Species from semi-arid environments have superior root morphology for searching for deep water compared with species of humid environments, including faster taproot extension rates (RER) and more efficient taproot depth penetration (STRL), but they show no difference in mean relative growth rate (RGR).