Supplemental material 1. Repeated-measures ANOVA for the effects of five years of drought (-50% ambient rainfall) on the cover of the dominant grass, Bouteloua eriopoda, the dominant shrub, Larrea tridentata, and on the abundance of subdominant species in grassland, shrubland and mixed vegetation (sites) in central New Mexico, USA. Statistically significant post-hoc comparisons (P<0.10) for significant interactions with treatment effects are also presented; d=drought treatment, a= ambient precipitation plots.

Factor / DF / SS / F / P / Rr2 / P / Contrasts
Bouteloua eriopoda / Year / 4,4 / 2.14 / 4.80 / 0.002 / 00.96 / <0.001
Site / 2,2 / 141.21 / 634.07 / <0.001
Treatment / 1,1 / 2.18 / 19.60 / <0.001
Year x Site / 8,8 / 0.40 / 0.44 / 0.889
Year x Treatment / 4,4 / 1.86 / 4.17 / 0.005 / 2004 to 2006 d<a
Site x Treatment / 2,2 / 0.02 / 0.10 / 0.902
Year x Site x Treatment / 8,8 / 0.76 / 0.85 / 0.561
Larrea tridentata / Year / 4,4 / 52.50 / 0.66 / 0.627 / 0.46 / 0.109
Site / 1,1 / 1364.82 / 68.15 / <0.001
Treatment / 1,1 / 3.74 / 0.19 / 0.668
Year x Site / 4,4 / 11.34 / 0.14 / 0.966
Year x Treatment / 4,4 / 28.99 / 0.36 / 0.834
Site x Treatment / 1,1 / 409.61 / 20.45 / <0.001 / Shrubland d>a, Mixed d<a
Year x Site x Treatment / 4,4 / 35.11 / 0.44 / 0.780
Forbs / Year / 4,4 / 36.92 / 82.25 / <0.001
Site / 2,2 / 9.42 / 41.96 / <0.001 / 0.90 / <0.001
Treatment / 1,1 / 0.23 / 2.01 / 0.161
Year x Site / 8,8 / 5.31 / 5.91 / <0.001
Year x Treatment / 4,4 / 6.06 / 13.50 / <0.001 / 2002 d<a, 2006 d>a
Site x Treatment / 2,2 / 0.49 / 2.16 / 0.124
Year x Site x Treatment / 8,8 / 1.25 / 1.40 / 0.216
Grasses / Year / 4,4 / 5.37 / 9.78 / <0.001 / 0.66 / <0.001
Site / 2,2 / 1.11 / 4.03 / 0.023
Treatment / \1,1 / 5.24 / 38.18 / <0.001
Year x Site / 8,8 / 1.60 / 1.45 / 0.193
Year x Treatment / 4,4 / 1.40 / 2.55 / 0.048 / 2002 to 2005 d<a
Site x Treatment / 2,2 / 1.33 / 4.84 / 0.011 / Grassland d<a, Mixed d<a
Year x Site x Treatment / 8,8 / 0.27 / 0.24 / 0.980
Shrubs / Year / 4,4 / 11.76 / 23.43 / <0.001 / 0.84 / <0.001
Site / 2,2 / 20.12 / 80.18 / <0.001
Treatment / 1,1 / 0.78 / 6.22 / 0.015
Year x Site / 8,8 / 3.85 / 3.83 / 0.001
Year x Treatment / 4,4 / 1.10 / 2.19 / 0.081 / 2004 and 2005 d<a
Site x Treatment / 2,2 / 0.32 / 1.27 / 0.289
Year x Site x Treatment / 8,8 / 1.73 / 1.72 / 0.112
Proportion annual to perennials / Year / 4,4 / 0.60 / 11.38 / 0.000 / 0.68 / <0.001
Site / 2,2 / 0.08 / 3.15 / 0.050
Treatment / 1,1 / 0.06 / 4.85 / 0.032
Year x Site / 8,8 / 0.52 / 4.89 / <0.001
Year x Treatment / 4,4 / 0.43 / 8.07 / <0.001 / 2002 d<a, 2004 and 2006 d>a
Year x Site x Treatment / 8,8 / 0.08 / 0.76 / 0.637
Subdominants / Year / 4,4 / 7.61 / 39.67 / <0.001 / 0.80 / <0.001
Site / 2,2 / 1.12 / 11.63 / <0.001
Treatment / 1,1 / 0.38 / 8.01 / 0.006
Year x Site / 8,8 / 0.69 / 1.79 / 0.097
Year x Treatment / 4,4 / 0.53 / 2.76 / 0.036 / 2002 and 2004 d<a
Site x Treatment / 2,2 / 0.43 / 4.43 / 0.016 / Grassland d<a, Mixed d<a
Year x Site x Treatment / 8,8 / 0.54 / 1.41 / 0.213

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