Dataset Information

Aboveground sink strength in forests controls the allocation of carbon below ground and its [CO2]-induced enhancement.

ABSTRACT: The partitioning among carbon (C) pools of the extra C captured under elevated atmospheric CO2 concentration ([CO2]) determines the enhancement in C sequestration, yet no clear partitioning rules exist. Here, we used first principles and published data from four free-air CO2 enrichment (FACE) experiments on forest tree species to conceptualize the total allocation of C to below ground (TBCA) under current [CO2] and to predict the likely effect of elevated [CO2]. We show that at a FACE site where leaf area index (L) of Pinus taeda L. was altered through nitrogen fertilization, ice-storm damage, and droughts, changes in L, reflecting the aboveground sink for net primary productivity, were accompanied by opposite changes in TBCA. A similar pattern emerged when data were combined from the four FACE experiments, using leaf area duration (LD) to account for differences in growing-season length. Moreover, elevated [CO2]-induced enhancement of TBCA in the combined data decreased from approximately 50% (700 g C m(-2) y(-1)) at the lowest LD to approximately 30% (200 g C m(-2) y(-1)) at the highest LD. The consistency of the trend in TBCA with L and its response to [CO2] across the sites provides a norm for predictions of ecosystem C cycling, and is particularly useful for models that use L to estimate components of the terrestrial C balance.

SUBMITTER: Palmroth S

PROVIDER: S-EPMC1748231 | biostudies-literature | 2006 Dec

REPOSITORIES: biostudies-literature

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Aboveground sink strength in forests controls the allocation of carbon below ground and its [CO2]-induced enhancement.

Palmroth Sari S Oren Ram R McCarthy Heather R HR Johnsen Kurt H KH Finzi Adrien C AC Butnor John R JR Ryan Michael G MG Schlesinger William H WH

Proceedings of the National Academy of Sciences of the United States of America 20061211 51

The partitioning among carbon (C) pools of the extra C captured under elevated atmospheric CO2 concentration ([CO2]) determines the enhancement in C sequestration, yet no clear partitioning rules exist. Here, we used first principles and published data from four free-air CO2 enrichment (FACE) experiments on forest tree species to conceptualize the total allocation of C to below ground (TBCA) under current [CO2] and to predict the likely effect of elevated [CO2]. We show that at a FACE site where ...[more]

PMID: 17159142

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Dataset Information

Aboveground sink strength in forests controls the allocation of carbon below ground and its [CO2]-induced enhancement.

Publications

Aboveground sink strength in forests controls the allocation of carbon below ground and its [CO2]-induced enhancement.

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