TY  - JOUR
AU  - Stahl, C.
AU  - Burban, B.
AU  - Bompy, F.
AU  - Jolin, Z.B.
AU  - Sermage, J.
AU  - Bonal, D.
PY  - 2010//
TI  - Seasonal variation in atmospheric relative humidity contributes to explaining seasonal variation in trunk circumference of tropical rain-forest trees in French Guiana
T2  - J. Trop. Ecol.
JO  - Journal of Tropical Ecology
SP  - 393
EP  - 405
VL  - 26
PB  - CAMBRIDGE UNIV PRESS
KW  - bark
KW  - drought
KW  - secondary growth
KW  - seasonality
KW  - tropical rain forest
KW  - water
N2  - Large seasonal variation in the rate of change in girth of tropical rain-forest tree species has been described, but its origin is still under debate. We tested whether this variation might be related to variation in atmospheric relative humidity through its influence on bark water content and thickness. Variation in trunk circumference of 182 adult trees was measured about twice a month in an undisturbed tropical rain forest over 18 mo using dendrometers. Furthermore, a laboratory experiment was conducted to test the direct influence of relative air humidity on bark water content and thickness. in the field, most trees displayed highly positive rates of change in girth at the onset of the wet season, while a quarter of the trees displayed negative changes during long dry seasons, whatever their total annual growth. This variation was correlated with environmental conditions, particularly with atmospheric relative humidity. Trees with high bark water content and thickness displayed a stronger decrease in girth during the dry season. in the chamber experiment, desiccation induced a decrease in the diameter of the trunk sections in tandem with a decrease in bark water content. As a result, seasonal variation in the rate of change in girth of tropical rain-forest trees reflects variation in trunk biophysical properties, through the influence of relative humidity on bark properties. but not directly variation in secondary growth.
SN  - 0266-4674
N1  - ISI:000279100600005
ID  - Stahl_etal2010
ER  -