Trends in tree growth and intrinsic water-use efficiency in the tropics under elevated CO2 and climate change

Journal article
(Review article)

Publication Details

Author(s): Rahman M, Islam M, Gebrekirstos A, Bräuning A
Journal: Trees-Structure and Function
Publication year: 2019
ISSN: 0931-1890


Key message: Increasing water-use efficiency, due to rising atmospheric CO
, did not stimulate radial growth in tropical trees, probably because negative impacts of changing climate on tree growth have overridden the small positive influence of rising atmospheric CO
. Abstract: Global environmental changes affect tree growth and physiological behavior across the major biomes around the world. However, it is not yet clear how tree growth and physiology of tropical trees responded to global environmental changes in a long term, yet such information is critical to get insight into how tropical trees will respond to future global changes. The main objective of this review article is to explore the long-term trends in tree growth, carbon isotope discrimination (Δ
C), intercellular CO
concentration (C
), and intrinsic water-use efficiency (iWUE) across the tropics and subtropics. We distinguished between data generated on plot levels or on species or tree individual levels. Stand-level growth trends were not consistent across the studies and plots, although recent studies indicated a declining growth trend. C
and iWUE consistently increased during the past decades, while Δ
C remained nearly constant. Increased iWUE either caused by higher photosynthetic capacity or reduced stomatal conductance did not translate into tree- and species-level radial growth, probably because assimilated carbon was allocated more to the root development to facilitate water absorption from moisture-limited soils rather than to basal area growth or xylem cell differentiation and maturation processess were impared by cavitation induced hydraulic limitations. Thus, higher temperature or drought-induced soil moisture deficit might have strongly impaired radial growth which has probably overridden the small positive effect of atmospheric CO
. Yet, disentangling the role of multiple drivers in explaining stem radial growth variation and their interactive effects on tropical trees under natural field conditions are not adequately studied and hence future research should focus on this aspect. Tree hydraulics should be taken into account in future research when predicting radial growth variability in tropical trees.

FAU Authors / FAU Editors

Bräuning, Achim Prof. Dr.
Lehrstuhl für Geographie (Physische Geographie)
Islam, Mahmuda
Institut für Geographie
Rahman, Mizanur
Lehrstuhl für Geographie (Physische Geographie)

External institutions with authors

World Agroforestry Centre

How to cite

Rahman, M., Islam, M., Gebrekirstos, A., & Bräuning, A. (2019). Trends in tree growth and intrinsic water-use efficiency in the tropics under elevated CO2 and climate change. Trees-Structure and Function.

Rahman, Mizanur, et al. "Trends in tree growth and intrinsic water-use efficiency in the tropics under elevated CO2 and climate change." Trees-Structure and Function (2019).


Last updated on 2019-24-05 at 09:23