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Background & Objectives
Background
Productive grasslands in many European countries are often based on pure stands of a
productive grass species with high feeding value, maintained by high levels of nitrogen fertiliser.
Some countries have developed grass-clover mixtures with four to eight species (e.g. Nyfeler et al
2009, Frankow-Lindberg, 2005, 2009; Frey, 1955; Suter et al., 2004) even under fertile conditions.
Recent ecological research has investigated the relationship between species diversity and the
provision of ecosystem services. In general, such research has been conducted in relatively
species-rich and nutrient-poor systems, and it seems that ecological processes may be more
effective when species diversity increases (Tilman et al., 1996) and it is critical to investigate
whether these effects are obtained under more nutrient rich intensive conditions. In the last
ten years interest in experimental investigation of the effects of diversity on ecosystem function
has quickened. A first generation of studies laid down preliminary results and methodology but this
has been critically examined and is being replaced by more detailed quantitative approaches to
experimental design and modelling of the results. A recent summary of the state of the art (Naeem
et al, 2009) has summarised several of these approaches. In this master class we will review
several of these methods and focus on the detail of one of them in particular, the
Diversity-Interaction modelling approach proposed in Kirwan et al, (2007, 2009).
Objectives
The aim of this Master Class is that participants will
1. Gain an overview of the aims and issues of biodiversity - ecosystem function
experiments
2. Learn the essential elements of the Diversity-Interaction modelling
approach
3. Gain practical experience in applying this approach to experimental data
4. Participate in discussions on model interpretation, implications and
limits
5. Understand the basics of designing biodiversity experiments using the simplex
approach and appreciate the strengths and weaknesses of various design strategies.
Literature
Kirwan L., Sebasti M.T., Finn J.A., Collins R.P., Porqueddu C., Helgadottir A., Baadshaug O.H.,
Brophy C., Coran C., Dalmannsdttir S., Delgado I., Elgersma A., Fothergill M., Frankow-Lindberg
B.E., Golinski P., Grieu P., Gustavsson A.M., Hglind M., Huguenin-Elie O., Iliadis C., Jrgensen M.,
Kadziuliene Z., Karyotis T., Lunnan T., Malengier M., Maltoni S., Meyer V., Nyfeler D.,
Nyknen-Kurki P., Parente J., Smit H.J., Thumm U. and Connolly J. (2007): Evenness drives consistent
diversity effects in an intensive grassland system across 28 European sites. Journal of Ecology 95,
530-539.
Kirwan L, Connolly J, Finn, JA, Brophy C, Lscher A, Nyfeler D and Sebasti MT (2009):
Diversity-Interaction Modelling - Estimating Contributions of Species Identities and Interactions
to Ecosystem Function. Ecology 90:2032-2038
Frankow-Lindberg B. (2005): Forage legumes in Sweden. In: Frankow-Lindberg B. et al. (eds.)
Adaptation and Management of Forage legumes - Strategies for Improved Reliability in Mixed Swards.
Proceedings of the 1st COST 852 workshop held in Ystad, Sweden 20-22 September 2004, pp. 13-20.
Sweden: Uppsala.
B. E. Frankow-Lindberg, C. Brophy, R. P. Collins, J., Connolly (2009): Biodiversity effects on
yield and unsown species invasion in a temperate forage ecosystem. Annals of Botany.
103:913-921
Frey E. (1955): Neue Standardmischungen fr den Futterbau. Mitteilungen fr die Schweizerische
Landwirtschaft 3(9),129-142.
Shahid Naeem, Daniel E. Bunker, Andy Hector, Michel Loreau, Charles Perrings (Editors) (2009):
Biodiversity, Ecosystem Functioning, and Human Wellbeing: An Ecological and Economic Perspective.
Oxford University Press, 384 pp
Nyfeler Daniel, Olivier Huguenin-Elie, Matthias Suter, Emmanuel Frossard, John Connolly and Andreas
Lscher (2009) Strong mixture effects among four species in fertilized agricultural grassland
led to persistent and consistent transgressive overyielding J Appl Ecol 46:683-691.
Suter D., Rosenberg E. and Mosimann E. (2004): Standardmischungen fr den Futterbau: Revison
2005-2008. Agrarforschung 11(9), 1-12.
Tilman D., Wedin D. and Knops J. (1996): Productivity and sustainability influenced by biodiversity
in grassland ecosystems. Nature 379, 718-720.
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