Table 1.

Effects of wolf spider density and warming treatments on community structure

Response	Fixed effects terms	Estimate	SE	df	t	P
Collembola	Intercept	0.243	0.029	77	8.225	0.000
	Soil moisture	−0.001	0.001	77	−1.887	0.063
	Control SD	−0.050	0.033	77	−1.520	0.133
	High SD	−0.048	0.033	77	−1.454	0.150
	Warming	−0.064	0.033	77	−1.930	0.057
	Poduromorpha	0.006	0.023	77	0.249	0.804
	Symphypleona	−0.155	0.023	77	−6.832	0.000
	Control SD × warming	0.085	0.046	77	1.843	0.069
	High SD × warming	0.098	0.046	77	2.132	0.036
Oribatid mites	Intercept	0.982	0.202	19	4.863	0.000
	Soil moisture	−0.008	0.004	19	−1.936	0.068
	Control SD	0.107	0.251	19	0.425	0.675
	High SD	−0.203	0.253	19	−0.802	0.433
	Warming	−0.186	0.252	19	−0.739	0.469
	Control SD × warming	0.180	0.355	19	0.509	0.617
	High SD × warming	0.286	0.353	19	0.810	0.428
Predatory mites	Intercept	0.134	0.044	19	3.036	0.007
	Soil moisture	0.001	0.001	19	1.118	0.278
	Control SD	−0.095	0.055	19	−1.730	0.100
	High SD	−0.051	0.055	19	−0.924	0.367
	Warming	−0.069	0.055	19	−1.253	0.226
	Control SD × warming	0.093	0.077	19	1.202	0.244
	High SD × warming	0.106	0.077	19	1.380	0.184
Intermediate predators	Intercept	0.005	0.002	19	2.786	0.012
(soil-dwelling)	Soil moisture	0.000	0.000	19	−0.505	0.620
	Control SD	0.000	0.002	19	0.035	0.972
	High SD	0.001	0.002	19	0.247	0.808
	Warming	−0.001	0.002	19	−0.343	0.735
	Control SD × warming	−0.002	0.003	19	−0.677	0.506
	High SD × warming	0.001	0.003	19	0.409	0.687
Intermediate predators	Intercept	0.026	0.008	19	3.384	0.003
(surface-active)	Soil moisture	0.000	0.000	19	−2.003	0.060
	Control SD	0.017	0.009	19	1.806	0.087
	High SD	−0.006	0.010	19	−0.627	0.538
	Warming	0.004	0.010	19	0.465	0.647
	Control SD × warming	−0.028	0.013	19	−2.113	0.048
	High SD × warming	−0.009	0.013	19	−0.641	0.529
Fungal biomass	Intercept	1.668	1.881	16	0.886	0.389
	Soil moisture	0.121	0.047	16	2.563	0.021
	Control SD	−0.513	2.210	16	−0.232	0.819
	High SD	0.673	2.228	16	0.302	0.767
	Warming	0.677	2.187	16	0.309	0.761
	Control SD × warming	−2.266	3.051	16	−0.743	0.468
	High SD × warming	−4.330	3.160	16	−1.370	0.190
Bacterial biomass	Intercept	−0.009	0.017	18	−0.495	0.626
	Soil moisture	0.001	0.000	18	1.838	0.083
	Control SD	−0.008	0.021	18	−0.379	0.709
	High SD	−0.002	0.022	18	−0.091	0.929
	Warming	−0.009	0.021	18	−0.416	0.683
	Control SD × warming	0.009	0.030	18	0.295	0.772
	High SD × warming	0.058	0.030	18	1.924	0.070

Mixed effects model results of community response variables, as predicted by wolf spider density (SD; reference category: low SD), warming (reference category: ambient temperature), and average soil moisture. All community response variables were measured in the field during the second summer of experimental treatment. Collembola, oribatid mites, predatory mites, and soil-dwelling intermediate predators were extracted from the upper organic soil layer; densities (individuals per cubic centimeter of soil) are expressed as the average from the June and July sampling periods. Surface-active intermediate predator abundance is the average total abundance from several bouts of live pitfall trapping. Fungal and bacterial biomass (mg per gram of soil) were sampled from the upper organic soil layer. Model results with the reference category for the wolf SD treatment as the control SD are shown in SI Appendix, Table S5.