Editor: Miguel Olalla-Tárraga
Vegetation–microclimate feedbacks in woodland–grassland ecotones
Article first published online: 25 OCT 2012
Published 2012. This article is a U.S. Government work and is in the public domain in the USA.
Global Ecology and Biogeography
Volume 22, Issue 4, pages 364–379, April 2013
How to Cite
D'Odorico, P., He, Y., Collins, S., De Wekker, S. F. J., Engel, V. and Fuentes, J. D. (2013), Vegetation–microclimate feedbacks in woodland–grassland ecotones. Global Ecology and Biogeography, 22: 364–379. doi: 10.1111/geb.12000
- Issue published online: 5 MAR 2013
- Article first published online: 25 OCT 2012
- Long-Term Ecological Research. Grant Numbers: NSF-DEB-0743678, NSF-DEB-0620482
- Alternative stable states;
- ecosystem engineering;
- mangrove-marsh transition;
- shrub encroachment;
- tree line;
- vegetation-microclimate feedback;
- woodland-grassland ecotone
Climatic conditions exert a strong control on the geographic distribution of many woodland-to-grassland transition zones (or ‘tree lines’). Because woody plants have, in general, a weaker cold tolerance than herbaceous vegetation, their altitudinal or latitudinal limits are strongly controlled by cold sensitivity. While temperature controls on the dynamics of woodland–grassland ecotones are relatively well established, the ability of woody plants to modify their microclimate and to create habitat for seedling establishment and growth may involve a variety of processes that are still not completely understood. Here we investigate feedbacks between vegetation and microclimatic conditions in the proximity to woodland–grassland ecotones.
We concentrate on arctic and alpine tree lines, the transition between mangrove forests and salt marshes in coastal ecosystems, and the shift from shrubland to grassland along temperature gradients in arid landscapes.
We review the major abiotic and biotic mechanisms underlying the ability of woody plants to alter the nocturnal microclimate by increasing the temperatures they are exposed to.
We find that in many arctic, alpine, desert and coastal landscapes the presence of trees or shrubs causes nocturnal warming thereby favouring the establishment and survival of woody plants.
Because of this feedback, trees and shrubs may establish in areas that would be otherwise unsuitable for their survival. Thus, in grassland–woodland transition zones both vegetation covers may be (alternative) stable states of the landscape, thereby affecting the way tree lines may migrate in response to regional and global climate change.