Tab. S1 Affiliation of taxa to trophic groups according to 15N enrichment, separately for wheat and maize plots. Average enrichment in 15N compared to maize and wheat plants in the respective plots (± SEM; wheat for treatments W+ and W-, maize for treatments M+ and M-) was used to assign species as decomposers or predators with predators being enriched in 15N by at least 1.6‰ as compared to the respective plant (∆15N), while in decomposers 15N enrichment was less than 1.6‰(Scheu and Falca 2000). Numbers in parentheses represent number of replicates. In cases of unclear affiliation species were assigned as decomposer or predators according to literature.

Taxonomic Group / Taxon / ∆15N
in maizeplots / ∆15N
in wheat plots / Trophic groupaffiliation / literature
Collembola / Heteromurusnitidus (Templeton, 1835) / 3.40 ± 0.33
(3) / 4.89 ± 0.91 (11) / mesofauna predator
Isotomaviridis
Bourlet, 1839 / 1.94 ± 1.05
(8) / 1.41 ± 0.53 (10) / mesofauna decomposer / Berg et al (2004)
LepidocyrtuscyaneusTullberg, 1871 / 2.43 ± 0.91
(3) / 3.29 ± 0.80
(12) / mesofauna predator
Pseudosinellaalba (Packard, 1873) / 4.62 ± 0.98
(3) / 4.78 ± 1.20
(7) / mesofauna predator
Protaphoruraarmata
(Tullberg, 1879) / 1.43 ± 0.87
(8) / 3.45 ± 1.06
(10) / mesofauna decomposers / Endlweber et al (2009)
Willowsiabuski
(Lubbock, 1869) / 7.25 ± 1.85
(4) / 2.55
(1) / mesofauna predator
Oribatida / Oppiellanova
(Oudemans, 1902) / 0.15 ± 0.39
(2) / -0.82 ± 1.68
(6) / mesofauna decomposer
Tectocepheusvelatus (Michael, 1880) / -0.99 ± 0.56
(9) / -1.49 ± 1.33
(7) / mesofauna decomposer
Gamasida / Alliphissiculus
(Oudemans, 1905) / 6.54 ± 0.66
(5) / 3.50 ± 0.78
(8) / mesofauna predator
Geholaspismandibularis (Berlese, 1904) / 5.13 ± 0.87
(2) / 8.38 ± 0.30
(4) / mesofauna predator
Hypoaspisaculeifer (Canestrini, 1884) / 3.49 ± 0.76
(5) / 5.96 ± 0.51
(12) / mesofauna predator
Lysigamasussp.
Karg, 1971 / 3.72 ± 0.95
(6) / 7.00 ± 0.71
(12) / mesofauna predator
Nenteriabreviunguiculata
(Willmann, 1949) / 13.85 ± 2.55
(2) / 6.30 ± 1.17
(8) / mesofauna predator
Pergamasuscrassipes
(Linnaeus, 1758) / 2.70 ± 0.33
(7) / 3.81 ± 0.59
(12) / mesofauna predator
Diplopoda / Blaniulusguttulatus
(Fabricius, 1798) / -1.86 ± 0.56
(16) / -0.22 ± 0.72
(8) / macrofauna
decomposer
Ophiodesmusalbonanus
(Latzel, 1895) / -1.36 ± 0.47
(8) / 0.50 ± 0.69
(4) / macrofauna decomposer
Polydesmussuperus
(Latzel, 1884) / -0.38 ± 1.29
(11) / 0.76 ± 0.80
(13) / macrofauna decomposer
Symphyla / Symphylellavulgaris
(Hansen, 1903) / 3.72 ± 0.47
(17) / 4.68 ± 0.52
(14) / macrofauna predator
Chilopoda / Lamyctesfulvicornis
Meinert, 1868 / 0.80 ± 0.45
(17) / 2.31 ± 0.94
(9) / macrofauna predator / Wolters and Ekschmitt (1997)
Necrophloeophaguslongicornis (Leach, 1814) / 3.75 ± 0.76
(5) / 5.15 ± 0.59
(10) / macrofauna predator
Coleoptera / Bembidionsp.
Latreille, 1802 / 4.42 ± 1.22
(3) / 3.57 ± 0.51
(11) / macrofauna predator
Paederinae
Lameere, 1900 / -0.39 ± 1.08
(7) / 1.88 ± 0.41
(10) / macrofauna / Assigned as decomposers in maize and predators in wheat(Dennis et al 1991)
Trechussp.
Clairville, 1806 / 0.33 ± 0.74
(4) / 3.47 ± 0.55
(8) / macrofauna predator / Mitchell (1963)
Carabidaelarvae / 4.86 ± 1.16
(8) / 4.57 ± 0.96
(6) / macrofauna predator
Elateridaelarvae / 2.43 ± 0.60
(12) / 2.86 ± 0.42
(13) / macrofauna predator
Staphylinidaelarvae / -2.25 ± 0.55
(9) / 2.18 ± 0.56
(11) / macrofauna / Assigned as decomposers in maize and predators in wheat(Dennis et al 1991)
Diptera / Cecidomyiidaelarvae / -1.19 ± 0.75
(5) / 1.15 ± 1.75
(6) / macrofauna decomposer
Muscidaelarvae / 2.46 ± 1.45
(5) / -1.40 ± 0.81
(6) / macrofauna / Assigned as decomposers in wheat and predators in maize (Frouz 1999)
Araneae / Meionetasp.
Hull, 1920 / 2.38 ± 1.39
(8) / 3.44 ± 0.64
(12) / macrofauna decomposer

References

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