Testing the benefits of grassland mixtures under experimental drought
Knowledge of the effect of severe weather events is a major uncertainty in predictions of the effect of climate change on agricultural systems. As part of the EU-funded AnimalChange project, we are testing the effects of severe weather events on grassland production, and the potential role of multi-species mixtures as a mitigation/adaptation measure.
We established a field experiment with experimental plots comprised of monocultures, two-species mixtures and four-species mixtures of grassland species used in grassland forage production. A rain shelter (see photo) was placed over one of a pair of similar plots to impose a drought stress for a period of several weeks. We are measuring the response of the vegetation to the drought by comparison with the control plot.
This work will be completed in late 2015.
As part of the AnimalChange project, we have also analysed data from a previous experiment. Results from a pan-European study, COST Action 852 ‘Quality Legume-Based Forage Systems for Contrasting Environments’, clearly demonstrated yield benefits of grass–legume mixtures compared to monocultures at 31 sites across a range of climatic conditions (Finn et al., 2013).Furthermore, mixed swards were more resistant to weed invasion, which is projected to be increasingly prevalent under climate change due to increased incidence of invasive plant species. This work has now been published (see below for links to the relevant publications), and the data is publicly available in Kirwan et al 2014.
See also the AnimalChange website: http://www.animalchange.eu/
For further information, contact Dr John Finn john.finn(at)teagasc.ie
Finn et al. 2013. Ecosystem function enhanced by combining four functional types of plant species in intensively managed grassland mixtures: a 3-year continental-scale field experiment. Journal of Applied Ecology, 50: 365–375.
Connolly, J., Cadotte, M.W., Brophy, C., Dooley, Á., Finn, J.A., Kirwan, L., Roscher, C., Weigelt, A. 2011. Phylogenetically diverse grassland communities are associated with pairwise interspecific processes that capture greater resources. Ecology 92: 1385-1392.
Kirwan et al. 2007. Evenness drives consistent diversity effects in intensive grassland systems across 28 European sites. Journal of Ecology 95: 530-539.
AnimalChange is a project supported by the EU - FP 7 (FP7/ 2007-2013) under Grant Agreement 266018.