Co-ordinating Editor: H. Bruelheide.
Substitutes for grazing in semi-natural grasslands – do mowing or mulching represent valuable alternatives to maintain vegetation structure?
Version of Record online: 18 SEP 2009
© 2009 International Association for Vegetation Science
Journal of Vegetation Science
Volume 20, Issue 6, pages 1086–1098, December 2009
How to Cite
Römermann, C., Bernhardt-Römermann, M., Kleyer, M. and Poschlod, P. (2009), Substitutes for grazing in semi-natural grasslands – do mowing or mulching represent valuable alternatives to maintain vegetation structure?. Journal of Vegetation Science, 20: 1086–1098. doi: 10.1111/j.1654-1103.2009.01106.x
- Issue online: 26 OCT 2009
- Version of Record online: 18 SEP 2009
- Received 18 May 2008;Accepted 26 June 2009.
- cross compliance;
- functional traits;
- RLQ analyses;
- vegetation response
Question: Which management treatments are suitable to replace historically applied grazing regimes? How and why does vegetation structure change following changes in management?
Location: Semi-natural calcareous dry grasslands in southwest Germany.
Methods: We analysed changes in floristic and functional composition induced by different management treatments (grazing, mowing, mulching, succession) in long-term experimental sites. First, floristic and functional distances between the initial conditions and the following years were determined. Second, we used RLQ analyses to include data on abiotic conditions, vegetation composition and functional traits in one common analysis. Finally, we applied cluster analyses on RLQ species scores to deduce functional groups.
Results: In contrast to the historical management regime of grazing, all alternative management treatments led to changes in floristic and functional composition, depending on their intensity with respect to biomass removal. The distance analyses showed that mulching twice per year and mowing did not lead to strong changes in floristic or functional composition. However, RLQ analysis clearly provided evidence that only the grazed sites are in equilibrium, indicating that vegetation change still goes ahead.
Conclusions: The current study clearly shows that RLQ is a powerful tool to elucidate ongoing processes that may remain hidden when separately analysing floristic and functional data. Alternative management treatments are not appropriate to sustain the typical disturbance dynamics of species-rich semi-natural grasslands. The less frequent an alternative management treatment is with respect to biomass removal, the less the floristic and functional structure can be maintained.