Location: Livestock and Range Research LaboratoryTitle: Geographic variation in the effects of disturbance, fungi, insects, and resilience on the abundance of a globally distributed plant Author
|Hierro, Jose - Consejo Nacional De Investigaciones Científicas Y Técnicas(CONICET)|
|Khetsuriani, Liana - Ilia State University|
|Andonian, Krikor - National Center For Agriculture And Forestry Technologies (CENTA)|
|Eren, Ozkan - Adnan Mederes University|
|Villarreal, Diego - University Of La Pampa|
|Janoian, Grigor - Nicaraguan Institute For Agricultural Technology (INTA)|
|Callaway, Regan - University Of Montana|
Submitted to: Ecography
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/19/2016
Publication Date: 7/1/2016
Citation: Hierro, J.L., Khetsuriani, L., Andonian, K., Eren, O., Villarreal, D., Janoian, G., Reinhart, K.O., Callaway, R.M. 2016. Geographic variation in the effects of disturbance, fungi, insects, and resilience on the abundance of a globally distributed plant. Ecography. doi:10.1111/ecog.02633.
Interpretive Summary: Whether yellow starthistle (Centaurea solstitialis) invades or not is geographically variable and difficult to predict. Our study found that invasion success was mainly encouraged by soil disturbance and the susceptibility of the system. In other words, invasion success was more likely when systems lacked resident plants and/or natural enemies capable of repelling the invader.
Technical Abstract: Aim: To assess the effects of disturbance, fungi, insects, and resilience on the abundance of a globally distributed ruderal, Centaurea solstitialis, in two regions with contrasting conditions within both native and non-native ranges. Location: The Caucasus (Georgia and Armenia) and south-western Turkey in the native range, and the western United States (US) and central Argentina in the non-native range of C. solstitialis. Methods: At each region, we established field experiments with soil disturbance (turnover and control) and biocide (fungicides, insecticide, and control) treatments, and recorded density, size, fecundity, and damage of sown C. solstitialis plants. In addition, we estimated the rate of vegetation recovery after disturbance (resilience) and related it to C. solstitialis density in experimental plots. Results: Disturbance increased the density of C. solstitialis everywhere, but its effects were stronger in the native Caucasus and non-native Argentina than native Turkey and non-native US. Fungicides had negative and positive effects on density in the Caucasus and the US, respectively, but resulted in no differences between regions. Insecticide did not alter C. solstitialis density in any region. Overall, plants were smaller and less fecund in Turkey than the other regions, except the US, and exhibited similar size and fecundity between the Caucasus, the US, and Argentina. Similarly, the greatest enemy attack was documented in Turkey. The resilience of the local plant community explained a large proportion of the variation in C. solstitialis density. Main conclusions: Our results suggest that the importance of factors controlling C. solstitialis abundance vary widely across its distribution, particularly within the native range. Also, our work shows that the performance of the species can be similarly high in parts of both its native and non-native range. Finally, community resilience could contribute to global variation in C. solstitialis abundance.