Scale dependence of canopy trait distributions along a tropical forest elevation gradient

ET AL; VAUGHN, NICHOLAS; MARTIN, ROBERTA E.; ...; ANDERSON, CHRISTOPHER B.; DÍAZ, SANDRA; KRYSTON, KATHERINE; ASNER, GREGORY P.

NEW PHYTOLOGIST

WILEY-BLACKWELL PUBLISHING, INC

Año: 2017 vol. 214 p. 973 - 988

0028-646X

SummaryAverage responses of forest foliar traits to elevation are well understood, but far less isknown about trait distributional responses to elevation at multiple ecological scales. This limitsour understanding of the ecological scales at which trait variation occurs in response to envi-ronmental drivers and change.We analyzed and compared multiple canopy foliar trait distributions using field sampling andairborne imaging spectroscopy along an Andes-to-Amazon elevation gradient. Field-estimatedtraits were generated from three community-weighting methods, and remotely sensed esti-mates of traits were made at three scales defined by sampling grain size and ecological extent.Field and remote sensing approaches revealed increases in average leaf mass per unit area(LMA), water, nonstructural carbohydrates (NSCs) and polyphenols with increasing elevation.Foliar nutrients and photosynthetic pigments displayed little to no elevation trend. Sampleweighting approaches had little impact on field-estimated trait responses to elevation. Plotrepresentativeness of trait distributions at landscape scales decreased with increasing eleva-tion. Remote sensing indicated elevation-dependent increases in trait variance and distribu-tional skew.Multiscale invariance of LMA, leaf water and NSC mark these traits as candidates for track-ing forest responses to changing climate. Trait-based ecological studies can be greatlyenhanced with multiscale studies made possible by imaging spectroscopy