Project properties
Title Why did the earthworm cross the road? Explaining earthworm exploration behavior
Group Soil Biology
Project type thesis
Credits 24-39
Supervisor(s) Jan Willem van Groenigen, Ingrid Lubbers
Examiner(s) prof.dr. Rachel Creamer
Contact info JanWillem.vanGroenigen@wur.nl Ingrid.Lubbers@wur.nl
Begin date 2025/03/01
End date
Description Earthworms are among the most important soil fauna. They contribute to the quality of soil by improving soil structure, increasing nutrient mineralisation, mixing residues into the soil, and many other processes. Thus, having large and diverse earthworm communities in the soil is an important factor for sustainable agricultural systems.
Yet, we know surprisingly little about the controlling factors for earthworm community composition: why are there many earthworms in one field, and only few in the next field? And what makes earthworms explore new environments?
We have developed a theory to explain earthworm behavior, where it ranges from "Active Seekers" (who are always eagerly exploring new areas in search of a better environment) to "Passive finders" (who are reluctantly pushed to explore new environments because of overpopulation). However, it is not clear yet whether this behavior is species-specific or determined by interactions between species and soil conditions - this is for you to find out!
In your research, you will install choice experiment setups with a gradient of soil pH, soil salinity level, food, and bulk density. Using various earthworm species, you will study their exploration behavior as response to soil conditions, and how those preferences change due to inter- and intra-specific competition. Your results will help us to complete our theory of earthworm colonization and help to devise soil management strategies to increase earthworm density and -diversity.
Used skills Apart from the usual required skills (performing a literature review, writing a proposal and a thesis, chemical and biological laboratory analysis, data processing and statistics, presentation) it is especially important for this topic that you are interested in earthworm ecology, and that you are resourceful, precise and independent with respect to labwork. We are looking for a student who is eager to setup and perform his/her own experiment as well as produce high quality data for a potential inclusion into a future scientific article.
Requirements Required courses for MSc thesis Soil Biology