Premium
Increased leaf reflectance in tropical trees under elevated CO 2
Author(s) -
Thomas Sean C.
Publication year - 2005
Publication title -
global change biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 4.146
H-Index - 255
eISSN - 1365-2486
pISSN - 1354-1013
DOI - 10.1111/j.1529-8817.2005.00907.x
Subject(s) - canopy , environmental science , reflectivity , atmospheric sciences , chlorophyll , ecosystem , radiative forcing , primary production , tree canopy , photochemical reflectance index , vegetation (pathology) , remote sensing , biology , botany , chlorophyll fluorescence , ecology , climate change , geology , optics , physics , medicine , pathology
Globally increasing atmospheric CO 2 concentrations are known to affect many aspects of plant physiology and development; however, little attention has been given to leaf and canopy optical properties. Three tropical trees in the Leguminosae, an important canopy tree family in many tropical forests, responded similarly to an experimental doubling of CO 2 partial pressure with a 9–23% increase in spectral leaf reflectance to light in the visible (400–700 nm) waveband. Decreased leaf chlorophyll content under elevated CO 2 may explain part of the observed increase in reflectance. However, analyses that statistically corrected for chlorophyll content effects on reflectance still indicated a significant CO 2 effect. This results, in conjunction with the spectral pattern of the response, suggests that the primary mechanism is increased optical masking of chlorophyll under elevated CO 2 . The magnitude of the increase in leaf reflectance is sufficient to suggest that increased canopy reflectance of tropical forests (and possibly other terrestrial ecosystems) may be an important negative feedback in the response of global net radiative climate forcing to increasing atmospheric CO 2 .