Disturbance and distributions: avoiding exclusion in a warming world

• Main Author: Douglas Sheil
• Format: Article
• Language: English
• Published: Resilience Alliance 2016-03-01
• Series: Ecology and Society
• Subjects: coexistence; competition-colonization trade-off; competitive displacement; competitive hierarchy; elevation; intermediate-disturbance-hypothesis; source-sink dynamics; succession
• Online Access: http://www.ecologyandsociety.org/vol21/iss1/art10/

I highlight how disturbance determines species distributions and the implications for conservation practice. In particular, I describe opportunities to mitigate some of the threats to species resulting from climate change. Ecological theory shows that disturbance processes can often slow or prevent the exclusion of species by competitors and that different disturbance regimes result in different realized niches. There is much evidence of disturbance influencing where species occur. For example, disturbance can lower the high elevation treeline, thus expanding the area for high elevation vegetation that cannot otherwise persist under tree cover. The role of disturbance in influencing interspecific competition and resulting species persistence and distributions appears unjustly neglected. I identify various implications, including opportunities to achieve in situ conservation by expanding plant species ranges and reducing species vulnerability to competitive exclusion. Suitable frequencies, scales, intensities, spatial configurations, and timings of the right forms of disturbance can improve the persistence of targeted species in a wide range of contexts. Such options could reduce the extinctions likely to be associated with climate change. More generally, these mechanisms and the resulting realizable niche also offer novel insights to understanding and manipulating species distributions.