Table 4.

Results of the best linear mixed-effects models assessing Pseudoroegneria spicata responses to the burned, warming, warming + drying treatments, and Bromus tectorum cover

Fixed effects							Random effects
Response	Predictor	Est.	SE	df	t value	P (>)	Variance
							Year	Residual
Cover (%)	Intercept	2.55	0.28	4.81	9.20	< 0.001	0.13 ± 0.37	0.47 ± 0.68
	Burned	− 0.08	0.12	121.03	− 0.66	0.511
	Warming	− 0.28	0.15	121.03	− 1.89	0.061
	Warming + drying	− 0.39	0.15	121.10	− 2.61	0.010
	B. tectorum cover (%)	− 0.21	0.06	122.96	− 3.31	0.001
Aboveground biomass (g)	Intercept	1.82	0.40	2.99	4.57	0.020	0.38 ± 0.61	0.47 ± 0.68
	Burned	− 0.14	0.12	121.04	− 1.14	0.256
	Warming	− 0.26	0.15	121.04	− 1.71	0.090
	Warming + drying	− 0.53	0.15	121.07	− 3.56	0.005
	B. tectorum cover (%)	− 0.16	0.06	122.36	− 2.54	0.012
Reproductive density (tillers plot−1)	Intercept	3.30	0.54	5.37	6.10	0.001	0.63 ± 0.79	1.21 ± 1.10
	Burned	− 0.19	0.20	125.05	− 0.99	0.326
	Warming	− 0.57	0.24	125.05	− 2.35	0.020
	Warming + drying	− 1.03	0.24	125.09	− 4.30	< 0.001
	B. tectorum cover (%)	− 0.26	0.10	127.11	− 2.60	0.010
Seed production (seeds plot−1)	Intercept	6.10	0.93	3.75	6.53	0.004	1.82 ± 1.35	3.85 ± 1.96
	Burned	0.31	0.35	121.06	− 0.89	0.374
	Warming	− 0.88	0.43	121.07	− 2.05	0.043
	Warming + drying	− 1.76	0.43	121.11	− 4.12	< 0.001
	B. tectorum cover (%)	− 0.43	0.18	122.85	− 2.41	0.017
Individual fecundity (mean seeds stem−1)	Intercept	2.75	0.10	26.61	27.98	< 0.001	0.005 ± 0.07	0.11 ± 0.33
	Burned	− 0.08	0.06	107.37	− 1.29	0.200
	Warming	− 0.01	0.08	107.66	− 0.19	0.848
	Warming + drying	− 0.09	0.08	107.52	− 1.17	0.244
	B. tectorum cover (%)	− 0.02	0.03	91.96	− 0.67	0.504

Values in bold indicate statistically significant differences (P < 0.05). Response variables were assessed at the plot level (0.75 m²), except individual fecundity, which is mean seeds stem⁻¹