Table 2.

Adjusted and unadjusted effect sizes (Hedges’ g) and CIs for all models (GCs and environmental stressors)

	GC/Environmental Stressor	Adjusted effect size	Adjusted CIs	Unadjusted effect size	Unadjusted CIs
GC main model	Climate change	−0.13	[−0.38,0.12]	−0.29	[−0.54,−0.04]
	Land-use intensification	−0.41∗	[−0.60,−0.22]	−0.58∗	[−0.77,−0.39]
	Pollution	−0.51∗	[−0.72,−0.29]	−0.71∗	[−0.92,−0.50]
	Nutrient enrichment	0.30∗	[0.10,0.51]	0.12	[−0.08,0.32]
	Invasive species	−0.11	[−0.48,0.26]	−0.23	[−0.61,0.15]
	Habitat fragmentation	0.18	[−0.21,0.57]	0.05	[−0.35,0.45]
Climate change	Flooding	0.31	[−0.05,0.68]	0.12	[−0.25,0.49]
	Drought	−0.31∗	[−0.55,−0.07]	−0.52∗	[−0.76,−0.28]
	Temperature change	0.006	[−0.22,0.21]	−0.20	[−0.41,0.02]
	CO2 increase	0.07	[−0.17,0.32]	−0.10	[−0.34,0.14]
Land-use intensification	Grazing	0.07	[−0.27,0.30]	−0.36∗	[−0.71,−0.01]
	Fire	−0.10	[−0.49,0.30]	−0.59∗	[−1.00,−0.18]
	Harvesting	−0.01	[−0.36,0.34]	−0.49∗	[−0.86,−0.12]
	Organic vs. Conventional	−0.67∗	[−1.01,−0.33]	−1.14∗	[−1.49,−0.78]
	Tillage	−0.41∗	[−0.67,−0.15]	−0.93∗	[−1.19,−0.66]
Pollution	Pesticides	−0.37∗	[−0.73,−0.002]	−0.41∗	[−0.78,−0.04]
	Metals	−0.91∗	[−1.23,−0.59]	−1.03∗	[−1.35,−0.70]
Nutrient enrichment	Synthetic fertilizers	−0.18	[−0.42,0.06]	0.05	[−0.16,0.27]
	Ca-liming + wood ash	−0.27	[−0.70,0.16]	−0.05	[−0.47,0.37]
	Compost	0.01	[−0.43,0.44]	0.29	[−0.13,0.70]
	Sludge (including biosolids)	−0.07	[−0.53,0.38]	0.13	[−0.31,0.58]
	Manure + slurry	0.48∗	[0.16,0.79]	0.75∗	[0.46,1.04]
	Residue + mulch	0.43∗	[0.11,0.75]	0.67∗	[0.37,0.97]
	Other organic fertilizers	0.34	[−0.05,0.73]	0.57∗	[0.20,0.95]
	Multiple fertilizer types	0.21	[−0.39,0.81]	0.47	[−0.12,1.05]
	Invasive species (all stressors mean)	0.52∗	[0.05, 0.98]	−0.15	[−0.55, 0.25]

Effect sizes were adjusted using methods in a study by Nakagawa et al.⁶⁵ to account for small-study effects.

^∗Effect sizes indicate statistically significant from zero.