Plant community and ecosystem responses to climate change

Understanding how ecological communities respond to changing climate is an important goal for plant ecologists. Our work asks how species’ responses to climate depend on their interactions with competitors, as well as natural enemies and mutualists above and below ground.

As well as altering interactions among species that already co-occur in communities today, climate change is reshuffling species distributions, leading to interactions between species with no prior ecological history. We study the ecological and evolutionary consequences of these novel interactions, and have shown that interactions with novel competitors could drive the responses of alpine plants to climate warming. We are currently combining field experiments with ecological modelling to predict how quickly alpine plant community composition will change as the climate continues to warm. We are also testing the potential for plants to adapt to combined pressures of changing climate and changing competition, and are exploring ways to predict the outcome of these interactions using information about species’ functional traits. In addition, we explore the consequences of changing interactions between plants and associated soil biota for plant and soil community structure following climate warming, as well the impacts of novel interactions on biogeochemical cycles and ecosystem functioning.

Contact

Jake Alexander

Key publications

Walker T.W.N., W. Weckwerth, L. Bragazza, L. Fragner, B.G. Forde, N.J. Ostle, C. Signarbieux, X. Sun, S.E. Ward, and R.D. Bardgett. 2019. Plastic and genetic responses of a common sedge to warming have contrasting effects on carbon cycle processes.
Ecology Letters 22:159-169.

Cardinaux, A., S.P. Hart, and J.M. Alexander. 2018.
Do soil biota influence the outcome of novel interactions between plant competitors?
Journal of Ecology 106:1853-1863.

Halbritter, A.H., S. Fior, I. Keller, R. Billeter, P.J. Edwards, R. Holderegger, S. Karrenberg, A.R. Pluess, A. Widmer, and J.M. Alexander. 2018.
Trait differentiation and adaptation of plants along elevation gradients.
Journal of Evolutionary Biology 31:784-800.

Alexander, J.M., L. Chalmandrier, J. Lenoir, T.I. Burgess, F. Essl, S. Haider, C. Kueffer, K. McDougall, A. Milbau, M.A. Nuñez, A. Pauchard, W. Rabitsch, L.J. Rew, N. Sanders, and L. Pellissier. 2018.
Lags in the response of mountain plant communities to climate change.
Global Change Biology 24:563-579.

Alexander, J.M., J.M. Diez, S.P. Hart, and J.M. Levine. 2016.
When climate reshuffles competitors: a call for experimental macroecology.
Trends in Ecology and Evolution 31:831-841.

Alexander, J.M., J.M. Diez, and J.M. Levine. 2015.
Novel competitors shape species’ responses to climate change.
Nature 525:515-518.

Moran, E.V. and J.M. Alexander. 2014.
Evolutionary responses to global change: lessons from invasive species.
Ecology Letters 17:637-649.