Leaf-level light compensation points in shade-tolerant woody seedlings

Photosynthetic traits such as respiration rate and light compensation point (LCP) likely play an important role in determining a plant's tolerance to low light levels, which can dictate long-term partitioning of the light supply among species and successional patterns (Givnish, 1988; Pacala et al., 1994). Walters & Reich (1999) reviewed patterns of leaf-level LCPs and associated leaf parameters in seedlings of tree species. They reported differences in mass-based dark respiration rates (Rd,mass) and specific leaf area (SLA), but no differences in area-based dark respiration rates (Rd,area), quantum yield (QY) or LCP among species that are considered shade-tolerant, shade-intolerant or intermediate in their tolerance of shade. Although other aspects of plant ecophysiology are certainly important for shade tolerance, is it true that leaf LCPs are unimportant?