Laufzeit: Februar 2016 - Januar 2020

Finanzierung / Financed by:Stipendienprogramm "Forschungsorientiertes Lehren und Lernen plus" (FoL+)

My dissertation focuses on the research of habitat preference of selected invertebrate groups (Hirudinea, Coleoptera, Trichoptera, Heteroptera and Gastropoda) to the water soldier (Stratiotes aloides) and other flora taxa of drainage ditches. The main research question of my project is:

How close are bonds between invertebrates and flora taxa and which factors influence these linkages?

For centuries, draining of wetland was a prerequisite for colonization and agricultural land use in Northern Germany. By the time, some of these ditches have been colonized by a species rich community, others even provide habitats for endangered species formally restricted to oxbow lakes or other types of floodplain waters. Moreover, the invertebrate fauna of drainage ditches is often characterized by a high level of productivity, which is of trophic value for neighboring environments.

So far, research in the field of invertebrate fauna paid little attention to habitats in drainage ditches. However, information on habitat preferences is essential, when ecological assessments or nature conservation measures are to be planned.

To answer the research question, empirical analyses of the invertebrate fauna and their population dynamics in drainage ditches will be applied. Furthermore, experimental changes of vegetation density and substrate availability will be performed to examine the effects on the invertebrate fauna. Currently it is suggested that habitat bonds to certain plants are facultative for the majority of macroinvertebrate species in drain ditches and are only obligatory for a few invertebrates. It is assumed that the bonds to surface and structural parameters are in the foreground.

Fig.: Stratiotes aloides in a marshland ditch in Bremen; Photo: D. Zacharias