The fastest water discharge through the soil column occurred in
treatments with A. caliginosa, where heavy outflow started after 1.5
and 1 min (Fig. 4). Here, 73% and 85% of the infiltrated water discharged
10 min after the outflow at 55 cm depth had started. In
treatments with L. terrestris and L. rubellus the outflowwas delayed,
but continued on a lower level, compared to treatments with
A. caliginosa. In the control treatments the outflows were considerably
delayed, starting 36 and 30 min after water infiltration
began (Fig. 4).
3.5. Litter loss and vertical SOC distribution
At the end of the experiment, in all treatments remaining litter
was found on the soil surface. Litter loss from soil surface was
highest in treatments with L. terrestris (Table 3). The rates were
lower in all other treatments but showed a high variability within
the earthworm species.
SOC-analyses revealed that only the top 20 cmwere considerably
enriched in SOC due to earthworm activity (Table 3). SOC-contents
were strongly influenced by L. terrestris. Here, this earthworm
affected an enrichment of SOC in the upper topsoil (0–5 cm) and in
the upper subsoil (15–20 cm). The overall lowest SOC-enrichment in
topsoil and subsoil was observed in treatments with A. caliginosa,
whereas L. rubellus did not show a clear trend in the vertical SOC
distribution (Table 3).