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  • Carbon allocation in an East African ant-acacia: field testing a 13C-labeling method for evaluating biotic impacts on the carbon cycle
Title: Carbon allocation in an East African ant-acacia: field testing a 13C-labeling method for evaluating biotic impacts on the carbon cycle
Tree carbon allocation is a dynamic process that depends on the tree’s environment, but we know relatively little about how biotic interactions influence these dynamics. In central Kenya, the loss of vertebrate herbivores and the savanna’s invasion by the ant Pheidole megacephala are disrupting mutualisms between the foundational tree Acacia (Vachellia) drepanolobium and its native ant defenders. Here, we piloted a 13Carbon (C) pulse-labeling method to investigate the influence of these biotic interactions on C allocation to ant partners by adult trees in situ. Trees withstood experimental conditions and took up sufficient labeled 13CO2 for 13C to be detected in various C sinks, including ant mutualists. The δ13C in ants collected shortly after labeling suggested that trees exposed to herbivores allocated relatively more newly assimilated C to native ant defenders. Our results demonstrate the viability of the pulse-labeling method and suggest that C allocation to ant partners depends on the biotic context of the tree, but further investigation with replication is needed to characterize such differences in relation to invasion and herbivore loss.  more » « less
Award ID(s):
1935498
PAR ID:
10478881
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Springer
Date Published:
Journal Name:
Plant Ecology
Volume:
224
Issue:
11
ISSN:
1385-0237
Page Range / eLocation ID:
953 to 963
Subject(s) / Keyword(s):
13C Acacia drepanolobium ant-plant mutualism Kenya pulse labeling
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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