Diverse outcomes of species interactions in an invaded annual plant community

Wainwright, Claire E. , Dwyer, John M., Hobbs, Richard J.  and Mayfield, Margaret M. (2016) Diverse outcomes of species interactions in an invaded annual plant community. Journal of Plant Ecology, 1-9. doi:10.1093/jpe/rtw102

Author Wainwright, Claire E. 
Dwyer, John M.
Hobbs, Richard J. 
Mayfield, Margaret M.
Title Diverse outcomes of species interactions in an invaded annual plant community
Journal name Journal of Plant Ecology   Check publisher's open access policy
ISSN 1752-9921
Publication date 2016-10-24
Sub-type Article (original research)
DOI 10.1093/jpe/rtw102
Open Access Status Not yet assessed
Start page 1
End page 9
Total pages 9
Place of publication Oxford, United Kingdom
Publisher Oxford University Press
Language eng
Formatted abstract
Aims: Despite acknowledgement that interactions among native and exotic species are important for determining the structure and diversity of novel communities, directed experiments using multiple exotics from the same system are rare. Recent observational studies have highlighted distinct ways that exotic species interface with resident natives across invaded communities. The correlative nature of these studies, however, has provided few details about the mechanisms driving distinct interaction outcomes within the same communities. Our aim was to determine how three exotic annual plant species with distinct relationships with local plant diversity impact the performance of a co-occurring native annual in the York gum–jam woodlands of Western Australia.

Methods: We grew species in experimental communities in growth chambers at varying total planting densities to assess how interaction outcomes varied among natives and exotics across a gradient of competition intensity. We measured a variety of performance responses, including survival, biomass and population-level and individual-level reproductive investment.

Important Findings: Overall, the effects of interspecific versus intraspecific competition on performance varied with the identity and density of exotic competitors. The exploitative exotic grass Bromus madritensis was dominant in polyculture, whereas the diminutive grass Pentameris airoides conferred weak intraspecific competition and interspecific facilitation on native Waitzia nitida. The exotic broadleaf forb, Hypochaeris glabra, suppressed growth and survival of W. nitida, while W. nitida had weakly negative, neutral or positive effects on all exotics. These outcomes highlight the complexity of interactions impacting the diversity, stability and structure of novel plant communities. As few of these communities contain a single exotic species, understanding the competitive dynamics occurring in diverse novel communities is critical for their conservation and restoration.
Keyword Annual plants
Biotic interactions
Novel ecosystems
Q-Index Code C1
Q-Index Status Provisional Code
Institutional Status UQ

Document type: Journal Article
Sub-type: Article (original research)
Collections: HERDC Pre-Audit
School of Biological Sciences Publications
Version Filter Type
Citation counts: Google Scholar Search Google Scholar
Created: Fri, 24 Mar 2017, 16:30:38 EST by Gail Walter on behalf of School of Biological Sciences