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While numerous studies have examined the effect of N deposition on ecosystem N retention, few have analyzed the involvement of plant species and climate warming in this process. We experimentally investigated the effects of increasing N deposition (N-exo) and climate warming on the fate of Nexo in a subalpine meadow and established the involvement of plant species. Using N-15 tracer, we tracked N-exo sprayed on the vegetation in belowground and aboveground plant biomasses (AGB) and in bulk soil over three growing seasons. We assessed the N-exo, absorption capacity of plant species and the contribution of N-exo to their AGB N pool. The meadow retained a large proportion of N-exo (approximate to 65%, mostly in AGB) for depositions up to four times the background N rate. N-exo present in the meadow compartments in year 2 was still present in year 3, suggesting that the ecosystem was unsaturated after three years of high N input. N. retention resulted more from an increase in N concentration in plant tissues than from the increase in AGB. The species-specific N-exo absorption capacity was inversely related to their AGB N concentration. N-exo accounted for up to 40% of total AGB N depending on the species and the N treatments. The contribution of species to ecosystem N-exo retention more contingent on their AGB than on their relative cover in the community, ranked as follows: C. vulgaris (14.0%) > N. stricta (7.0%)> other Poaceae C. caryophyllea (2.5%) > other Eudicotyledons (1.5%)> non-vascular species = P. erecta > Fabaceae (0.8-0.2%). Climate warming increased AGB and decreased tissue N concentration. No warming-N-exo interaction was observed. Thus, Pyrenean subalpine meadows that have not undergone a decline in plant species richness in recent decades paradoxically display a high potential to sequester atmospheric N deposition. (C) 2018 Elsevier Ltd. All rights reserved.