Fig 1.
Test system for exposing organisms to five bait-lamina strips.
Fig 2.
Daily feeding activity at different relative soil moisture contents for (A) the earthworm, Eisenia andrei, and (B) for the enchytraeid, Enchytraeus albidus.
Daily feeding activity is expressed as % of consumed bait per day, and relative soil moisture content is expressed as % of maximum water holding capacity (% WHC). For the earthworm tests, n = 10 at 52% WHC and n = 5 at all other relative moisture contents. For the enchytraeid test, n = 3 at 68% WHC, n = 4 at all other relative moisture contents. Significant differences from the reference moisture (i.e., 52% WHC for E. andrei and 49% WHC for E. albidus) are indicated by * (p < 0.05), ** (p < 0.01) and *** (p < 0.001), according to Dunnet’s post-hoc with Holm’s correction.
Table 1.
Parameters of the multiple regression analysis for the daily feeding activity response to the two predictors ‘moisture’ and ‘species’, with interaction between the two factors.
Fig 3.
Linear regressions of the daily feeding activity of each test species exposed to different soil moistures up to their respective peak.
Black lines indicate the linear regression, and the 95% confidence interval is indicated by the grey shades. Daily feeding activity is expressed as % of consumed bait per day, and relative soil moisture content is expressed as % of maximum water holding capacity (% WHC). Each symbol (black dots for Eisenia andrei and black triangle for Enchytraeus albidus) represents values of daily feeding activity of all replicates (n = 10 at 52% WHC and n = 5 at all other moisture contents for E. andrei, n = 3 at 68% WHC and n = 4 for all other moisture contents for E. albidus).
Table 2.
Parameters of the multiple regression analysis for the daily feeding activity response to the two predictors ‘moisture’ and ‘experiments’, with 1) interaction between the two factors and with 2) no interaction.
Fig 4.
Linear regressions of the daily feeding activity (in % of pierced holes) of each experiment exposed to different soil moistures (gravimetric water content, %).
Black lines indicate the linear regression, and the 95% confidence interval is indicated by the grey shades. Daily feeding activity is expressed as % of consumed bait per day, and soil moisture content is expressed as % of the soil dry weight). Each symbol (black dots for E. andrei, this study, black triangle for E. albidus, this study, black squares for Campiche et al. 2015 [20] represents values of daily feeding activity of all replicates (n = 10 at 23% moisture content and n = 5 at all other moisture contents for E. andrei, n = 3 at 31% moisture content and n = 4 for all other moisture contents for E. albidus, n = 4 for Campiche et al. 2015).