Intraspecific root and leaf trait variation with tropical forest successional status: consequences for community-weighted patterns
O_LIQuantifying the dimensions and magnitude of intraspecific root trait variation is key to understanding the functional trade-offs in the belowground plant strategies of tropical forest trees. Additionally, accurately measuring how belowground functional trait variation relates to soil environment and forest age is crucial to tropical forest modeling efforts.\nC_LIO_LIWe sampled leaf and root morphologies from 423 juvenile trees of 72 species from 14 Angiosperm families along a 6.6 km transect that corresponded to an environmental gradient in decreasing soil fertility and texture with increasing forest age.\nC_LIO_LIWe observed within-lineage conservative functional trait-shifts in root and leaf morphological traits along the transect. From secondary to primary forest, average leaf area increased 7 cm2 and average root system diameter increased 0.4 mm. Mean specific leaf area decreased by 0.8 m2 kg-1, specific root length decreased by 3.5 m kg-1, and root branching intensity decreased by 0.3 tips cm-1. Leaf thickness and root tissue density showed no change.\nC_LIO_LIWe coupled trait measurements to a network of 164 1/16th-ha plots across a Chinese tropical forest reserve, to scale individual trait measurements up to the community-level, accounting for forest age.\nC_LIO_LIFor most traits, intraspecific trait variation negatively covaried with species compositional turnover between plots in younger versus older forest to compound and create greater community-weighted differences in trait values than would be observed if intraspecific variation in traits with forest age was not accounted for.\nC_LIO_LISummary Root morphologies are variable with local scale variation in soil fertility and texture. Accurately understanding broader (i.e. forest)-scale patterns in root functional traits, requires attention to underlying environmental variation in soil resources, which interacts with environmental filtering of plant communities.\nC_LI