Table 1 GLM table of effects of plant diversity (1, 3, and 6 plant species per microcosm) on plant shoot and root biomass [g microcosm⁻¹], Shannon diversity of root biomass, root complementarity effect [g microcosm⁻¹], root selection effect [g microcosm⁻¹], root net biodiversity effect [g microcosm⁻¹], exudate richness [# of compounds], exudate amount [μM], soil bacterial biomass [nmol g⁻¹ soil dry weight], fungal biomass [nmol g⁻¹ soil dry weight], and ratio between fungal and bacterial biomass.

2.48 ± 0.86

2.53 ± 0.81

3.05 ± 0.89

1, 90

l

4.10

0.046

4.57 ± 1.71

5.40 ± 2.34

7.19 ± 2.30

1, 90

l

17.98

<0.001

0.00 ± 0.00

0.86 ± 0.18

1.35 ± 0.14

1, 88

l

699.5

<0.001

nc

−0.65 ± 1.15

−0.39 ± 0.66

1, 32

c

1.80

0.187

nc

1.82 ± 3.50

3.30 ± 2.62

1, 32

c

0.56

0.458

nc

1.18  ±  2.96

2.92  ±  2.76

1, 32

c

3.11

0.086

2.55 ± 1.46

2.50 ± 1.42

3.50 ± 2.17

2, 51

c

1.58

0.215

1.05 ± 0.51

1.00 ± 0.54

1.50 ± 0.41

2, 51

c

3.29

0.045

22.70 ± 6.54

21.58 ± 5.84

25.70 ± 3.84

2, 85

c

3.78

0.027

3.52 ± 2.44

3.64 ± 2.24

5.08 ± 2.24

1, 86

l

9.39

0.003

0.16 ± 0.08

0.17 ± 0.08

0.20 ± 0.09

1, 84

l

4.46

0.038