Table 2.
Colony development and honey production in relation to fixed effects
| Model | Model typea | Effect measurea | Estimatesb | Degrees of freedom | F b | P b |
|---|---|---|---|---|---|---|
| Colony development c | ||||||
| Number of capped brood cells | Full modeld | Intercept | 4445.953 | |||
| Seed-treatment | −23.591 | 1, 16 | 0.04 | 0.837 | ||
| Bloom | −271.905 | 1, 110 | 6.06 | 0.015 | ||
| Year | 783.702 | 1, 19 | 42.12 | <0.001 | ||
| Seed-treatment x Bloom | 171.907 | 1, 110 | 2.42 | 0.122 | ||
| Seed-treatment x Year | −41.545 | 1, 17 | 0.13 | 0.719 | ||
| Bloom x Year | 466.244 | 1, 110 | 17.83 | <0.001 | ||
| Seed-treatment x Bloom x Year | 276.231 | 1, 110 | 6.26 | 0.014 | ||
| 2013 | Intercept | 3656.020 | ||||
| Seed-treatment | 20.252 | 1, 7 | 0.22 | 0.872 | ||
| Bloom | −738.149 | 1, 75 | 46.74 | <0.001 | ||
| Seed-treatment x Bloom | −104.324 | 1, 75 | 0.10 | 0.380 | ||
| 2014 | Intercept | 5098.070 | ||||
| Seed-treatment | −60.730 | 1, 4 | 0.08 | 0.790 | ||
| Bloom | 194.339 | 1, 35 | 0.94 | 0.338 | ||
| Seed-treatment x Bloom | 448.139 | 1, 35 | 5.02 | 0.032 | ||
| Number of adult bees | Full modeld | Intercept | 5866 | |||
| Seed-treatment | −61 | 1, 17 | 0.24 | 0.629 | ||
| Bloom | 1274 | 1, 110 | 161.40 | <0.001 | ||
| Year | −439 | 1, 20 | 11.26 | 0.003 | ||
| Seed-treatment x Bloom | 206 | 1, 110 | 4.22 | 0.042 | ||
| Seed-treatment x Year | −17 | 1, 17 | 0.02 | 0.893 | ||
| Bloom x Year | −1647 | 1, 110 | 269.79 | <0.001 | ||
| Seed-treatment x Bloom x Year | −140 | 1, 110 | 1.94 | 0.166 | ||
| Spring assessment | ||||||
| Number of capped brood cells | 2014 | Intercept | 6.684 | |||
| Seed-treatment | 0.029 | 1 | X² = 0.82 | 0.821 | ||
| Number of adult bees | 2014 | Intercept | 4421.691 | |||
| Seed-treatment | −164.356 | 1, 7 | 0.19 | 0.674 | ||
| Honey production | Full modeld | Intercept | 9.425 | |||
| Seed-treatment | −0.095 | 1, 16 | 0.02 | 0.880 | ||
| Year | −1.378 | 1, 18 | 4.47 | 0.049 | ||
| Seed-treatment x Year | 0.009 | 1, 16 | <0.01 | 0.989 | ||
a The number of capped brood cells and the number of adult bees in relation to clothianidin seed-treatment, bloom (before or after the oilseed rape flowering period) and year (2013 and 2014) using linear mixed effect models
b Main effects/interactions were estimated using sum-to-zero contrasts and the deviation of the second level (after, clothianidin, 2014) of each factor (Bloom: before/after, Seed-treatment: control/clothianidin and Year: 2013/2014) from to the grand mean (intercept) is presented. P values < 0.05 are highlighted in bold
c Measurements were taken during pre- and post- exposure assessment
d Full model: n = 14, clothianidin-treated; n = 12, control fields; repeated measurements. 2013: n = 8 per treatment. 2014: n = 6, clothianidin-treated; n = 4 control fields