Eco-evolutionary outsiders: Establishing in a distantly related
neighbourhood delays and reorganizes nutrient recycling
Abstract
Rapid environmental change forces long-lived plants like trees to
immigrate into zones still occupied by phylogenetically distantly
related species. Does such phylogenetic isolation (PI) change the trees’
ecosystem functioning such as litter decomposition? We studied oaks
(Quercus petraea) of low and high PI, reciprocally transplanting
their litters to identify effect of aboveground litter quality and
belowground decomposer biota. Across 8 and 14 months we quantified
decomposition (mass loss, C-loss and N-loss), decomposer biota (Acari,
Collembola, microbes) and 13C/12C
ratio. Across 14 months, aboveground PI retarded decomposition (mass and
C loss). Across 8 and 14 months, above- and belowground PI extensively
altered relationships between decomposition and abundances/diversities
of different soil biota, reduced microbial activity and
13C/12C ratios. Overall, coexistence
of trees with distant relatives impedes and severely re-organizes C and
N recycling. Such negative ecosystem feedback might prevent trees from
tracking and conserving abiotic niches under environmental change.