Fine roots stimulate nutrient release during early stages of leaf litter decomposition in a Central Amazon rainforest

• DOI: 10.1007/s11104-021-05148-9
• Publication Date: 2021-10-02T03:37:34Z
• Authors: Nathielly P. Martins; Lucia Fuchslueger; Katrin Fleischer; Kelly M. Andersen; Rafael L. Assis; Fabricio B. Baccaro; Plínio B. Camargo; Amanda L. Cordeiro; Adriana Grandis; Iain P. Hartley; Florian Hofhansl; Laynara F. Lugli; David M. Lapola; Juliane G. Menezes; Richard J. Norby; Anja Rammig; Jessica S. Rosa; Karst J. Schaap; Bruno Takeshi; Oscar J. Valverde...; Carlos A. Quesada
• Keywords: Decomposer; Plant litter; Litter; Nutrient cycle

Abstract Purpose Large parts of the Amazon rainforest grow on weathered soils depleted in phosphorus and rock-derived cations. We tested hypothesis that this ecosystem, fine roots stimulate decomposition nutrient release from leaf litter biochemically by releasing enzymes, exuding labile carbon stimulating microbial decomposers. Methods monitored a Central tropical rainforest, where were either present or excluded, over 188 days added substrates (glucose citric acid) fully factorial design. tracked mass loss, remaining carbon, nitrogen, cation concentrations, extracellular enzyme activity concentrations. Results Fine root presence did not affect loss but significantly increased cations litter. In roots, acid phosphatase was 43.2% higher, while neither stoichiometry, nor activities targeting carbon- nitrogen-containing compounds changed. Glucose additions when present, enhanced exclusions. Citric reduced biomass nitrogen phosphorus, regardless exclusion. Conclusions conclude plant significant amounts phosphatases into layer mobilize without affecting loss. Our results further indicate inputs ( i.e . glucose) can production decomposers, highlighting potential importance plant-microbial feedbacks forest ecosystems.