TY - JOUR AU - Urbina, I. AU - Grau, O. AU - Sardans, J. AU - Ninot, J.M. AU - Peñuelas, J. PY - 2020// TI - Encroachment of shrubs into subalpine grasslands in the Pyrenees changes the plant-soil stoichiometry spectrum T2 - Plant Soil JO - Plant and Soil SP - 37 EP - 53 VL - 448 IS - 1-2 PB - Springer KW - Nutrient stocks KW - Plant strategy KW - Plant-soil stoichiometry KW - Shrub encroachment KW - Subalpine grassland succession KW - aboveground biomass KW - biogeochemical cycle KW - carbon sequestration KW - ectomycorrhiza KW - fungus KW - grass KW - nitrogen KW - nutrient uptake KW - shrub KW - soil-vegetation interaction KW - stoichiometry KW - subalpine environment KW - succession KW - Europe KW - Pyrenees KW - Fungi N2 - Aims: Shrub encroachment has been reported over a large proportion of the subalpine grasslands across Europe and is expected to have an important impact on the biogeochemical cycle of these ecosystems. We investigated the stoichiometric changes in the plant-soil system along the succession (e.g. increase in encroachment from unencroached grassland to mature shrubland) at two contrasting sites in the Pyrenees. Methods: We analyzed the chemical composition (C, N,15N, P, K, Ca, Mg and Fe) in the soil and in the aboveground plant compartments (leaves, leaf-litter and stems) of the main herbaceous species and shrubs at three contrasting stages of the succession: unencroached grassland, young shrubland and mature shrubland. Results: The plant-soil stoichiometry spectrum differed between the successional stages. Shrub encroachment generally increased the concentration of C and Ca and the C:N ratio and often reduced to concentrations of N, P and K in the leaves and leaf-litter, while several soil nutrient concentrations (N, P, K Ca and Mg) decreased. The stocks of C, N, P, Ca, and Mg in the total aboveground biomass increased with encroachment. Conclusions: Shrub encroachment favored the dominance of long-lived species with low concentrations of N and P in the plant-soil compartments, high C:nutrient ratios in the aboveground biomass and increase the uptake of N through ericoid or ectomycorrhizal fungi. We highlight the role of shrubs in the sequestration of C and nutrients through the allocation to the aboveground biomass. The changes in plant-soil elemental composition and stocks suggest a slowdown of the biogeochemical cycles in the subalpine mountain areas where shrub encroachment occurred. © 2020, Springer Nature Switzerland AG. SN - 0032079x (Issn) UR - http://dx.doi.org/10.1007/s11104-019-04420-3 N1 - exported from refbase (http://php.ecofog.gf/refbase/show.php?record=983), last updated on Mon, 08 Feb 2021 15:39:02 -0300 ID - Urbina_etal2020 ER -