Leaf traits and resprouting ability in the Mediterranean basin

Abstract

1 Resprouting is a primary persistence mechanism in fire- and drought-prone ecosystems. Plants with this mechanism (resprouters) tend to exhibit deeper root-system and higher stem and leaf water potential. We test the extent to which non-resprouters counteract their lower root allocation by means of leaf traits that confer higher drought resistance. 2 Leaf mass per area (LMA), leaf dry matter content (LDMC), area-based leaf nitrogen content (LNCa) and integrated water-use efficiency (δ13C) were measured for 33 woody species in the eastern Iberian Peninsula. Phylogeny and biogeographical history (Tertiary vs Quaternary) were considered in all comparisons. 3 Non-resprouters showed higher LMA, LNCa and δ13C when considering either all species, or Quaternary species only. Tertiary and Quaternary resprouters differed exclusively in δ13C, which was higher for Tertiary species. 4 These results suggest that, at leaf level, non-resprouters have higher potential for structural resistance to drought and higher water-use efficiency than resprouters. We propose that the existence of a physiological trade-off at leaf level between drought resistance and carbon gain should explain the leaf-trait values exhibited by resprouters.