Untangling positive and negative biotic interactions: Views from above and below ground in a forest ecosystem

Loading...
Thumbnail Image

Persistent link to this item

Statistics
View Statistics

Journal Title

Journal ISSN

Volume Title

Title

Untangling positive and negative biotic interactions: Views from above and below ground in a forest ecosystem

Published Date

2010

Publisher

Ecological Society of America

Type

Article

Abstract

In ecological communities, the outcome of plant–plant interactions represents the net effect of positive and negative interactions occurring above and below ground. Untangling these complex relationships can provide a better understanding of mechanisms that underlie plant–plant interactions and enhance our ability to predict population, community, and ecosystem effects of biotic interactions. In forested ecosystems, tree seedlings interact with established vegetation, but the mechanisms and outcomes of these interactions are not well understood. To explore such mechanisms, we manipulated above- and belowground interactions among tree seedlings, shrubs, and trees and monitored seedling survival and growth of six species (Pinus banksiana, Betula papyrifera, P. resinosa, Quercus rubra, P. strobus, and Acer rubrum) in mature pine-dominated forest in northern Minnesota, USA. The forest had a moderately open canopy and sandy soils. Understory manipulations were implemented in the forest interior and in large gaps and included removal of shrubs (no interactions), tieback of shrubs (belowground), removal of shrubs with addition of shade (aboveground), and unmanipulated shrubs (both below- and aboveground). We found that shrubs either suppressed or facilitated seedling survival and growth depending on the seedling species, source of interaction (e.g., above- or belowground), and ecological context (e.g., gap or forest interior). In general, shrubs strongly influenced survival and growth in gaps, with more modest effects in the forest interior. In gaps, the presence of shrub roots markedly decreased seedling growth and survival, supporting the idea that belowground competition may be more important in dry, nutrient-poor sites. Shrub shade effects were neutral for three species and facilitative for the other three. Facilitation was more likely for shade-tolerant species. In the forest interior, shrub shade negatively affected seedling survival for the most shade-intolerant species. For several species the net effect of shrubs masked the existence of both positive and negative interactions above and below ground. Our results highlight the complexity of plant–plant interactions, demonstrate that outcomes of these interactions vary with the nature of resource limitation and the ecophysiology of the species involved, and suggest that ecological theory that rests on particular notions of plant–plant interactions (e.g., competition) should consider simultaneous positive and negative interactions occurring above and below ground.

Description

Related to

Replaces

License

Collections

Series/Report Number

Funding information

Isbn identifier

Doi identifier

10.1890/09-1663.1

Previously Published Citation

Rebecca A. Montgomery, Peter B. Reich, and Brian J. Palik 2010. Untangling positive and negative biotic interactions: views from above and below ground in a forest ecosystem. Ecology 91:3641–3655.

Suggested citation

Montgomery, Rebecca A; Reich, Peter B; Palik, Brian J. (2010). Untangling positive and negative biotic interactions: Views from above and below ground in a forest ecosystem. Retrieved from the University Digital Conservancy, 10.1890/09-1663.1.

Content distributed via the University Digital Conservancy may be subject to additional license and use restrictions applied by the depositor. By using these files, users agree to the Terms of Use. Materials in the UDC may contain content that is disturbing and/or harmful. For more information, please see our statement on harmful content in digital repositories.