manually checked and verified in reference to species known to exist at the site. Separate taxa tables were created based on amplicons and each of the and ITS trnL Asteraceae Poaceae amplicons. Samples with fewer than 550, 1000, and 100 sequences were removed from taxa tables based on ITS, and ITS amplicons, respectively. We calculated trnL, Asteraceae Poaceae the relative abundance of individual plant genera in each sample using the sequence counts. trnL Because the gene yields limited taxonomic resolution for the and we trnL Asteraceae Poaceae, replaced the total relative abundances of taxa (mostly unknown genera) within these two families with normalized relative abundances of genera determined using the ITS sequence data. Plant traits All leaf and root traits were measured using standard protocols (Cornelissen 2003). et al., Briefly, we measured specific leaf area, specific root length, leaf dry matter content and root dry matter content by weighing and scanning the fresh leaf and root samples. The samples were then oven dried at 60 °C for 48 h and their dry weights measured. The scanned digital images were analyzed in WinRhizo (Reagent Instruments Inc., Ville de Québec, QC, Canada) to determine leaf areas, root lengths and root diameters. Shoot and root N and C contents from the plants and the field sample plant communities were measured on an Elementar Vario elemental analyzer (Langenselbold, Germany). In both cases, plant material was freeze-dried and thoroughly homogenized prior to measurement. Soil characteristics Soil characteristics were measured as in Orwin (2010). pH was measured using a ratio of 1 et al. g fresh soil: 2.5 ml dH2O. Dissolved inorganic N, individual ions (NO3-N , NH4-N), and net N mineralization were assessed using 1 M KCl extracts, and dissolved organic N was assessed
manually checked and verified in reference to species known to exist at the site. Separate taxa tables were created based on trnL amplicons and each of the Asteraceae and Poaceae ITS amplicons. Samples with fewer than 550, 1000, and 100 sequences were removed from taxa tables based on trnL, Asteraceae ITS, and Poaceae ITS amplicons, respectively. We calculated the relative abundance of individual plant genera in each sample using the trnL sequence counts. Because the trnL gene yields limited taxonomic resolution for the Asteraceae and Poaceae, we replaced the total relative abundances of taxa (mostly unknown genera) within these two families with normalized relative abundances of genera determined using the ITS sequence data. Plant traits All leaf and root traits were measured using standard protocols (Cornelissen et al., 2003). Briefly, we measured specific leaf area, specific root length, leaf dry matter content and root dry matter content by weighing and scanning the fresh leaf and root samples. The samples were then oven dried at 60 °C for 48 h and their dry weights measured. The scanned digital images were analyzed in WinRhizo (Reagent Instruments Inc., Ville de Québec, QC, Canada) to determine leaf areas, root lengths and root diameters. Shoot and root N and C contents from the plants and the field sample plant communities were measured on an Elementar Vario elemental analyzer (Langenselbold, Germany). In both cases, plant material was freeze-dried and thoroughly homogenized prior to measurement. Soil characteristics Soil characteristics were measured as in Orwin et al. (2010). pH was measured using a ratio of 1 g fresh soil: 2.5 ml dH2O. Dissolved inorganic N, individual ions (NO3-N , NH4-N), and net N mineralization were assessed using 1 M KCl extracts, and dissolved organic N was assessed
UK_grassland_ms_2018_01_14_ISME_rev2.docx