Impact of land-use change towards perennial energy crops on earthworm population

The aim of the study was to investigate the impact of the cultivation of newly introduced perennial bioenergy crops on earthworm species composition, number and biomass at an experimental site in Western Germany. The included crops were Szarvazi (Agropyron elongatum), Switchgras (Panicum virgatum), Sida (Sida hermaphrodita), Silphie (Silphium perfolatum), Igniscum (Fallopia sachalinensis), and a wild flower mix (WFM) relative to silage (Zea maize). In sum, earthworm population at that site consisted of 8 species, Lumbricus rubellus and Allolobophora cupulifera being dominant species. Species number varied in a range of WPM (8) > Szarvazi (7) > Sida (6) > Silphie, Igniscum (5) > Switchgras, Maize (4). Earthworm number and biomass significantly increased in all newly introduced energy crops. On comparison within the perennial crops, it was found that earthworm number was significantly highest in Sida and lowest in Switchgras plots. The differences within the remaining crops were small and not significant. From an agro-ecological point of view and deduction from earthworm population data, it might be concluded that Szarvasi, Sida and wild flower mix can be seen as important energy crops in future bioenergy production in Western Germany.