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  • Species interactions amplify functional group responses to elevated CO 2 and N enrichment in a 24‐year grassland experiment
Title: Species interactions amplify functional group responses to elevated CO 2 and N enrichment in a 24‐year grassland experiment
Abstract Plant functional groups (FGs) differ in their response to global changes, although species within those groups also vary in such responses. Both species and FG responses to global change are likely influenced by species interactions such as inter‐specific competition and facilitation, which are prevalent in species mixtures but not monocultures. As most studies focus on responses of plants growing in either monocultures or mixtures, but rarely both, it remains unclear how interspecific interactions in diverse ecological communities, especially among species in different FGs, modify FG responses to global changes. To address these issues, we leveraged data from a 16‐species, 24‐year perennial grassland experiment to examine plant FG biomass responses to atmospheric CO2, and N inputs at different planted diversity. FGs differed in their responses to N and CO2treatments in monocultures. Such differences were amplified in mixtures, where N enrichment strongly increased C3 grass success at ambient CO2and C4 grass success at elevated CO2. Legumes declined with N enrichment in mixtures at both CO2levels and increased with elevated CO2in the initial years of the experiment. Our results suggest that previous studies that considered responses to global changes in monocultures may underestimate biomass changes in diverse communities where interspecific interactions can amplify responses. Such effects of interspecific interactions on responses of FGs to global change may impact community composition over time and consequently influence ecosystem functions.  more » « less
Award ID(s):
1831944 2224852 2021898
PAR ID:
10553073
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Global Change Biology
Volume:
30
Issue:
8
ISSN:
1354-1013
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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