Effects of glyphosate-based herbicides and their active ingredients on earthworms, water infiltration and glyphosate leaching are influenced by soil properties

Environmental Sciences Europe

Table 3 After-treatment period: earthworm activity in response to weed control types (WCT: glyphosate-based herbicides GBH, active ingredients AI, or hand weeding as control) and soil organic matter levels (SOM). GLM/analysis of deviance was used for cast numbers and surface activity, LM/ANOVA for cast mass; time period (4 weeks), soil moisture, temperature and electrical conductivity was used as covariates

Factors	Mean cast numbers (no. pot⁻¹)			Mean cast mass (g pot⁻¹)			Mean surface activity (toothpick index)
	Df	LR Χ²	Pr (> Χ²)	Df	F value	Pr (> F)	Df	LR Χ²	Pr (> Χ²)
Weed control type	2	7.558	0.023	2	2.213	0.120	2	11.533	0.003
SOM	1	0.421	0.517	1	0.000	0.996	1	0.667	0.414
Covar. time	1	1.075	0.300	1	0.004	0.952	1	0.221	0.638
Covar. soil moist. (%)	1	11.291	0.001	1	0.000	0.986	1	5.154	0.023
Covar. soil temp. (°C)	1	0.052	0.819	1	0.000	0.998	1	8.417	0.004
Covar. soil cond. (mS m⁻¹)	1	0.054	0.816	1	0.156	0.694	1	0.749	0.387
WCT x SOM	2	0.905	0.636	2	1.042	0.360	2	1.281	0.527
Residuals	NA			261			NA

	z value	Pr( >\|z\|)	t value	Pr(> t)	z value	Pr( >\|z\|)
Multiple comparisons of means (Tukey)
AI – control	− 2.188	0.073	NA	NA	− 2.822	0.013
GBH – control	− 2.838	0.013	NA	NA	− 3.498	0.001
GBH—AI	− 0.688	0.771	NA	NA	− 0.693	0.768

Significant treatment effects are indicated in bold. No multiple comparisons were performed for cast mass because of lacking main effects
NA not applicable