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Title: Reduced aboveground tree growth associated with higher arbuscular mycorrhizal fungal diversity in tropical forest restoration
Abstract

Establishing diverse mycorrhizal fungal communities is considered important for forest recovery, yet mycorrhizae may have complex effects on tree growth depending on the composition of fungal species present. In an effort to understand the role of mycorrhizal fungi community in forest restoration in southern Costa Rica, we sampled the arbuscular mycorrhizal fungal (AMF) community across eight sites that were planted with the same species (Inga edulis, Erythrina poeppigiana, Terminalia amazonia,andVochysia guatemalensis) but varied twofold to fourfold in overall tree growth rates. TheAMFcommunity was measured in multiple ways: as percent colonization of host tree roots, byDNAisolation of the fungal species associated with the roots, and through spore density, volume, and identity in both the wet and dry seasons. Consistent with prior tropical restoration research, the majority of fungal species belonged to the genusGlomusand genusAcaulospora, accounting for more than half of the species and relative abundance found on trees roots and over 95% of spore density across all sites. GreaterAMFdiversity correlated with lower soil organic matter, carbon, and nitrogen concentrations and longer durations of prior pasture use across sites. Contrary to previous literature findings,AMFspecies diversity and spore densities were inversely related to tree growth, which may have arisen from trees facultatively increasing their associations withAMFin lower soil fertility sites. Changes toAMFcommunity composition also may have led to variation in disturbance susceptibility, host tree nutrient acquisition, and tree growth. These results highlight the potential importance of fungal–tree–soil interactions in forest recovery and suggest that fungal community dynamics could have important implications for tree growth in disturbed soils.

 
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NSF-PAR ID:
10019512
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Ecology and Evolution
Volume:
6
Issue:
20
ISSN:
2045-7758
Page Range / eLocation ID:
p. 7253-7262
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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