Distributions of fine root length and mass with soil depth in natural ecosystems of southwestern Siberia SUPPLEMENTARY MATERIAL Félix Brédoire 1,2,, Polina Nikitich 3,4, Pavel A Barsukov 5, Delphine Derrien 3, Anton Litvinov 6, Helene Rieckh 7, Olga Rusalimova 5, Bernd Zeller 3, and Mark R Bakker 2,1 1 INRA, UMR 1391 ISPA, F-33140 Villenave d Ornon, France 2 Bordeaux Sciences Agro, UMR 1391 ISPA, F-33170 Gradignan, France 3 INRA, UR 1138 BEF, F-54280 Champenoux, France 4 Tomsk State University, Tomsk, Russia 5 Institute of Soil Sciences and Agrochemistry, Novosibirsk, Russia 6 Novosibirsk State Pedagogical University, Novosibirsk, Russia 7 Institute of Soil Landscape Research, Leibniz Centre for Agricultural Landscape Research (ZALF), Müncheberg, Germany Last Update: 29/09/2015 Corresponding author: felix.bredoire@bordeaux.inra.fr; Tel.: +33 5 57 12 26 55; Fax: +33 5 57 12 25 15 1
Supplementary Tle 1: Results of all the one-way ANOVA testing a site effect. Site effect tested on Veg. Cover Species Diameter F df p sig. lev. 1 Roots bottom pit Forest overall coarse 4.5922 5 0.01424 * overall fine 3.5211 5 0.03435 * Grassland overall coarse 0.7514 4 0.5793 overall fine 1.4598 4 0.2852 FRL in litter Forest overall < 0.8 1.6188 5 0.2287 aspen < 0.8 2.6003 5 0.08126. non-aspen < 0.8 1.915 5 0.1654 Grassland overall < 0.8 3.3321 4 0.05582. FRM in litter Forest overall < 0.8 1.3484 5 0.3096 aspen < 0.8 1.5792 5 0.239 non-aspen < 0.8 2.1616 5 0.1272 Grassland overall < 0.8 1.9599 4 0.1317 beta FRL Forest overall < 0.8 8.4154 5 0.001276 ** aspen < 0.8 1.8589 5 0.1757 non-aspen < 0.8 2.2469 5 0.1223 Grassland overall < 0.8 2.7179 4 0.091. Total FRL Forest overall < 0.8 4.8921 5 0.01135 * aspen < 0.8 7.3919 5 0.002233 ** non-aspen < 0.8 2.0074 5 0.1497 Grassland overall < 0.8 12.21 4 0.00073 *** FRL top 30 cm Forest overall < 0.8 7.5791 5 0.002008 ** aspen < 0.8 2.8304 5 0.06488. non-aspen < 0.8 2.1838 5 0.1302 Grassland overall < 0.8 3.8992 4 0.03683 * beta FRM Forest overall < 0.8 3.5493 5 0.03351 * aspen < 0.8 3.6112 5 0.03175 * non-aspen < 0.8 1.4347 5 0.2864 Grassland overall < 0.8 1.5297 4 0.2663 Total FRM Forest overall < 0.8 4.7124 5 0.01299 * aspen < 0.8 3.7766 5 0.02754 * non-aspen < 0.8 2.3462 5 0.105 Grassland overall < 0.8 8.1198 4 0.003487 ** FRM top 30 cm Forest overall < 0.8 4.7898 5 0.01225 * aspen < 0.8 7.0496 5 0.002725 ** non-aspen < 0.8 1.8805 5 0.1778 Grassland overall < 0.8 1.7126 4 0.2232 1 Significance levels: *** p < 0.001; ** p < 0.01; * p < 0.05;. p < 0.1. 2
Supplementary Tle 2: Length and mass of fine roots of a diameter < 0.8 mm in the litter layer. Mean of 3 replicates per site ± standard error of the mean. Different letters denote significant differences at p < 0.05 level using a Tukey post-hoc comparison. ANOVA results are given in 1. FRL (m m 2 ) FRM (g m 2 ) Veg. Cover Species Site mean se stat mean se stat Forest Overall FS1 17.81 5.46 a 1.04 0.34 a FS2 38.87 19.15 a 4.80 3.40 a FS3 31.87 3.84 a 2.85 0.54 a FS4 23.20 9.58 a 1.12 0.72 a ST1 11.50 3.16 a 0.49 0.16 a ST2 8.23 2.55 a 0.63 0.33 a Aspen FS1 1.66 1.66 a 0.18 0.18 a FS2 21.67 11.90 a 3.29 2.42 a FS3 2.12 1.06 a 0.39 0.22 a FS4 4.15 3.46 a 0.35 0.30 a ST1 0.74 0.25 a 0.23 0.11 a ST2 0.00 0.00 a 0.00 0.00 a Non-aspen FS1 16.15 4.62 a 0.87 0.28 a FS2 17.20 8.74 a 1.51 1.02 a FS3 29.75 4.60 a 2.46 0.56 a FS4 19.05 6.58 a 0.77 0.44 a ST1 10.76 2.95 a 0.26 0.05 a ST2 8.23 2.55 a 0.63 0.33 a Grassland Overall FS1 5.13 3.34 a 0.11 0.09 a FS2 0.89 0.89 a 0.06 0.06 a FS3 15.93 9.90 a 0.29 0.18 a FS4 18.68 1.57 a 0.44 0.20 a ST2 0.00 0.00 a 0.00 0.00 a 3
Supplementary Tle 3: Structure of the total fine root length calculated over 120 cm. Mean and standard error of the mean of 3 pits per site. Results are expressed in % of total FRL, diameters are in mm. FS1 FS2 FS3 FS4 ST1 ST2 Veg. Cover Species Diameter mean se mean se mean se mean se mean se mean se Forest Aspen overall 78.44 14.00 31.51 4.50 65.63 8.21 37.13 10.84 54.08 11.35 52.16 8.57 Non-aspen overall 21.56 14.00 68.49 4.50 34.37 8.21 62.87 10.84 45.92 11.35 47.84 8.57 Overall Aspen < 0.2 58.44 1.16 68.13 5.98 70.42 5.30 66.68 6.46 49.50 6.66 61.29 4.06 0.2-0.4 26.69 1.42 24.27 6.20 17.87 4.07 25.61 6.09 38.02 5.66 29.50 3.05 0.4-0.8 11.00 1.81 6.18 1.03 9.64 1.91 6.48 1.97 6.95 0.84 8.09 2.87 0.8-1.2 3.65 2.15 1.41 0.77 1.86 0.41 0.80 0.80 5.52 2.80 0.43 0.43 1.2-2.0 0.22 0.22 0.00 0.00 0.21 0.21 0.43 0.43 0.00 0.00 0.68 0.68 Non-aspen < 0.2 86.63 10.17 78.01 8.95 88.52 4.95 89.62 2.99 69.10 17.00 67.94 17.12 0.2-0.4 12.98 10.30 11.33 3.52 11.44 4.95 9.52 3.56 16.35 9.16 24.79 16.98 0.4-0.8 0.14 0.14 6.33 1.52 0.04 0.04 0.63 0.46 10.32 5.21 7.27 4.77 0.8-1.2 0.25 0.25 2.67 2.59 0.00 0.00 0.24 0.24 4.23 4.23 0.00 0.00 1.2-2.0 0.00 0.00 1.66 1.66 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Overall < 0.2 65.71 5.72 74.40 7.72 77.96 1.39 81.75 4.63 54.22 7.18 61.22 7.86 0.2-0.4 22.47 4.06 15.69 4.21 14.56 2.01 14.47 3.90 30.02 5.26 30.54 7.74 0.4-0.8 9.20 2.72 6.22 1.31 6.10 0.96 3.06 1.15 9.24 1.87 7.71 3.65 0.8-1.2 2.41 1.25 2.45 1.69 1.21 0.29 0.53 0.29 6.52 1.15 0.28 0.28 1.2-2.0 0.21 0.21 1.24 1.24 0.17 0.17 0.18 0.18 0.00 0.00 0.24 0.24 Grassland < 0.2 90.12 2.48 91.42 2.40 80.64 1.00 81.24 0.24 87.01 2.48 0.2-0.4 7.81 1.28 6.94 1.65 17.35 1.86 15.53 0.99 9.61 2.63 0.4-0.8 1.51 0.93 0.88 0.28 1.43 0.73 2.64 0.86 2.36 0.93 0.8-1.2 0.56 0.35 0.76 0.50 0.58 0.42 0.50 0.25 1.02 0.83 1.2-2.0 0.00 0.00 0.00 0.00 0.00 0.00 0.09 0.09 0.00 0.00 overall 100.00 100.00 100.00 100.00 100.00 4
Supplementary Tle 4: Structure of the total fine root mass calculated over 120 cm. Mean and standard error of the mean of 3 pits per site. Results are expressed in % of total FRM, diameters are in mm. FS1 FS2 FS3 FS4 ST1 ST2 Veg. Cover Species Diameter mean se mean se mean se mean se mean se mean se Forest Aspen overall 86.08 9.95 36.95 12.89 83.18 4.07 52.80 12.15 62.75 22.48 70.13 8.53 NonAspen overall 13.92 9.95 63.05 12.89 16.82 4.07 47.20 12.15 37.25 22.48 29.87 8.53 Overall Aspen < 0.8 78.95 12.90 85.87 7.29 74.91 2.02 89.05 10.95 79.58 10.87 81.06 10.1 0.8-2 21.05 12.90 14.13 7.29 25.09 2.02 10.95 10.95 20.42 10.87 18.94 10.1 NonAspen < 0.8 96.63 3.37 74.67 21.58 100.00 0.00 86.75 11.60 76.41 23.59 100 0 0.8-2 3.37 3.37 25.33 21.58 0.00 0.00 13.25 11.60 23.59 23.59 0 0 Overall < 0.8 83.21 9.51 71.45 16.17 78.97 2.78 89.62 5.92 63.11 11.26 86.11 8.44 0.8-2 16.79 9.51 28.55 16.17 21.03 2.78 10.38 5.92 36.89 11.26 13.89 8.44 Grassland Overall < 0.8 93.45 4.26 90.47 4.86 83.97 11.64 87.73 6.14 77.92 18.09 0.8-2 6.55 4.26 9.53 4.86 16.03 11.64 12.27 6.14 22.08 18.09 overall 100.00 100.00 100.00 100.00 100.00 5
Forest Grassland a Species aspen non aspen 0.6 a overall kg m 2 0.4 a 0.2 b b b 0.0 FS1 FS2 FS3 FS4 ST1 ST2 FS1 FS2 FS3 FS4 ST1 ST2 Supplementary Figure 1: Total fine root mass over 120 cm in forest (left panel) and grassland (right panel). Mean and standard error of the mean of 3 replicates per site. In forest, total fine root mass is detailed for aspen (dark grey) and non-aspen (light grey). Results presented for roots with a diameter < 0.8 mm. Different letters denote significant differences at p < 0.05 level using a Tukey post-hoc comparison. ANOVA results are given in Supplementary Tle 1. 6
Forest Grassland Depth (cm) Site (mean β) FS1 (0.981) FS2 (0.962) FS3 (0.965) FS4 (0.963) ST1 (0.948) ST2 (0.945) Site (mean β) FS1 (0.962) FS2 (0.955) FS3 (0.957) FS4 (0.946) ST2 (0.911) Cumulative Fine Root Mass (Y) Supplementary Figure 2: Cumulative fine root mass (cumulative proportion) as a function of soil depth in forest (left panel) and grassland (right panel) for the six sites. The figure shows the differences between sites. Species are not sorted, diameter < 0.8 mm. The line was generated with the mean β (of 3 pits) from Eq. 6: Y = 1 β d (Gale_1987). 0 25 FS1 FS2 FS3 FS4 ST2 0.911 0.955 0.957 0.946 0.962 0.963 0.945 Depth (cm) 50 75 0.981 0.962 0.965 Veg. cover 100 Forest Grassland 125 0.0 0.5 1.00.0 0.5 1.00.0 0.5 1.00.0 0.5 1.00.0 0.5 1.0 Cumulative Fine Root Mass (Y) Supplementary Figure 3: Cumulative fine root mass (cumulative proportion) as a function of soil depth in forest and grassland for the six sites. The figure shows the differences between forest and grassland within sites and the quality of model fitting. Species are not sorted, diameter < 0.8 mm. Points are field measurements (3 per site and depth) and line was generated with the mean β (of 3 pits) from Eq. 6: Y = 1 β d (Gale_1987). 7
Depth (cm) 0 25 50 75 100 FS1 FS2 FS3 FS4 ST1 ST2 0.945 0.932 0.884 0.933 0.941 0.972 0.967 0.944 0.946 0.963 0.971 0.981 Species aspen non aspen 125 0.0 0.5 1.00.0 0.5 1.00.0 0.5 1.00.0 0.5 1.00.0 0.5 1.00.0 0.5 1.0 Cumulative Fine Root Mass (Y) Supplementary Figure 4: Cumulative fine root mass (cumulative proportion) as a function of soil depth in forest for the six sites. The figure shows the differences between aspen and non-aspen fine root systems within forest sites and the quality of model fitting. Aspen and non-aspen (understorey vegetation) are sorted, diameter < 0.8 mm. Points are field measurements (3 per site and depth) and line was generated with the mean β (of 3 pits) from Eq. 6: Y = 1 β d (Gale_1987). 8