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Title: Ant invasion is associated with lower root density and different root distribution of a foundational savanna tree species
Some invasive ants have worldwide distributions and impose substantial impacts on human society and native biodiversity. Yet we know little about how ants impact soil ecosystems in general, much less how soil ecosystems shift when invasive ants move in. We excavated the coarse roots of a monodominant savanna tree in invaded and uninvaded areas to test the hypothesis that the presence of invasive ants would be associated with changes in root distribution and biomass across the landscape. We found that in the presence of invasive ants, trees had a shifted distribution of lateral coarse roots, with proportionally less root biomass near the surface and far from tree stems. In addition, the density of lateral coarse-root biomass was ~ 20% lower for trees within invaded landscapes. Our results suggest that soil-nesting invasive ants can drive important changes in rooting strategy for a tree species that serves a foundational role in the biogeochemical cycles of vertisol savannas.  more » « less
Award ID(s):
1935498
NSF-PAR ID:
10478878
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Springer
Date Published:
Journal Name:
Biological Invasions
Volume:
25
Issue:
6
ISSN:
1387-3547
Page Range / eLocation ID:
1683 to 1691
Subject(s) / Keyword(s):
["Ant acacia","invasive soil macrofauna","Pheidole megacephala","root functional traits","soil ecosystem engineering","Vachellia drepanolobium"]
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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