Dataset Information

Rainfall drives variation in rates of change in intrinsic water use efficiency of tropical forests.

ABSTRACT: Rates of change in intrinsic water use efficiency (W) of trees relative to those in atmospheric [CO2] (ca) have been mostly assessed via short-term studies (e.g., leaf analysis, flux analysis) and/or step increases in ca (e.g., FACE studies). Here we use compiled data for abundances of carbon isotopes in tree stems to show that on decadal scales, rates of change (dW/dca) vary with location and rainfall within the global tropics. For the period 1915-1995, and including corrections for mesophyll conductance and photorespiration, dW/dca for drier tropical forests (receiving ~?1000?mm rainfall) were at least twice that of the wettest (receiving ~?4000?mm). The data also empirically confirm theorized roles of tropical forests in changes in atmospheric 13C/12C ratios (the 13C Suess Effect). Further formal analysis of geographic variation in decade-to-century scale dW/dca will be needed to refine current models that predict increases in carbon uptake by forests without hydrological cost.

SUBMITTER: Adams MA

PROVIDER: S-EPMC6694106 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Rainfall drives variation in rates of change in intrinsic water use efficiency of tropical forests.

Adams Mark A MA Buckley Thomas N TN Turnbull Tarryn L TL

Nature communications 20190814 1

Rates of change in intrinsic water use efficiency (W) of trees relative to those in atmospheric [CO2] (ca) have been mostly assessed via short-term studies (e.g., leaf analysis, flux analysis) and/or step increases in ca (e.g., FACE studies). Here we use compiled data for abundances of carbon isotopes in tree stems to show that on decadal scales, rates of change (dW/dca) vary with location and rainfall within the global tropics. For the period 1915-199 ...[more]

PMID: 31413322

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Dataset Information

Rainfall drives variation in rates of change in intrinsic water use efficiency of tropical forests.

Publications

Rainfall drives variation in rates of change in intrinsic water use efficiency of tropical forests.

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