The most exciting aspect of this study “Increase of fast nutrient cycling in grassland microcosms through insect herbivory depends on plant functional composition and species diversity” (Nitschke et al)- for me – was to take our experiences and results from the field site – the Jena Experiment that was designed for elucidating mechanisms of diversity effects – and to incorporate them into a microcosm experiment under well controlled conditions.
Here, we aimed at tracking the way of nutrients from the intact plant, over an insect herbivore and its feeding characteristics, into the soil, and over to another trophic level – And to judge the role of plant diversity and functional composition along that way.
- Some aspects of the course showed very clearly (e.g. the release of nutrients with feeding and the relevance of the plant functional groups),
- some were surprising (e.g. both throughfall pH and P increased with herbivory intensity and faeces accumulation – diversity having a similar effects, although independently of herbivore intensity),
- and yet others were challenging (e.g. clear soil microbial responses only occurred at high levels of herbivory).
Finally, stepping back a little and taking our field site results into account, formed a broader picture and gave some new perspectives.
Besides the change of perspective the study brought about and the various methods we applied, it was very inspiring and rewarding to work together in a team of people that have realized quite different niches within Biodiversity Ecosystem Functioning-space.