Competition overwhelms the positive plant–soil feedback generated by an invasive plant
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Invasive plant species can modify soils in a way that benefits their fitness more than the fitness of native species. However, it is unclear how competition among plant species alters the strength and direction of plant–soil feedbacks. We tested how community context altered plant–soil feedback between the non-native invasive forb Lespedeza cuneata and nine co-occurring native prairie species. In a series of greenhouse experiments, we grew plants individually and in communities with soils that differed in soil origin (invaded or uninvaded by L. cuneata) and in soils that were live vs. sterilized. In the absence of competition, L. cuneata produced over 60% more biomass in invaded than uninvaded soils, while native species performance was unaffected. The absence of a soil origin effect in sterile soil suggests that the positive plant–soil feedback was caused by differences in the soil biota. However, in the presence of competition, the positive effect of soil origin on L. cuneata growth disappeared. These results suggest that L. cuneata may benefit from positive plant–soil feedback when establishing populations in disturbed landscapes with few interspecific competitors, but does not support the hypothesis that plant–soil feedbacks influence competitive outcomes between L. cuneata and native plant species. These results highlight the importance of considering whether competition influences the outcome of interactions between plants and soils.
KeywordsLespedeza cuneata Prairie Invasion Soil microbes Plant–soil feedback
Thanks to Brennan Keiser for laboratory assistance. KMC was supported by a Tyson Postdoctoral Fellowship from Tyson Research Center and a Postdoctoral Research Fellowship in Biology from the National Science Foundation (#1103667). TMK was supported by the Alexander von Humboldt Foundation in the framework of the Alexander von Humboldt Professorship of TM Knight. We would also like to thank Editor Gehring, Luke Flory, and 3 anonymous for providing comments that greatly improved this manuscript.
Author contribution statement
KMC and TMK conceived and designed the experiments. KMC performed the experiments and analyzed the data. KMC and TMK wrote the manuscript.
- Eddy TA, Moore CM (1998) Effects of Sericea Lespedeza (Lespedeza cuneata (Dunmont) G. Don) invasion on oak savannas in Kansas. Trans Wisconsin Acad Sci Arts Lett 86:57–62Google Scholar
- Guernsey WJ (1977) Sericea Lespedeza (Lespedeza cuneata): Its use and management. U.S. Department of Agriculture Farmers Bulletin No. 2245Google Scholar
- He W-M, Cui Q-G (2009) Manipulation of soil biota in ecological research. In: Web Ecol. http://www.web-ecol.net/9/68/2009/we-9-68-2009.pdf. Accessed 12 Nov 2014
- Lowe S, Browne M, Boudjelas S, De Poorter M (2000) 100 of the world's worst invasive alien species: a selection from the global invasive species database. Invasive Species Specialist Group (ISSG), International Union for Conservation of Nature (IUCN), AucklandGoogle Scholar
- Miller JH (2006) Nonnative invasive plants of southern forests: a field guide for identification and control. USDA Forest Service, Southern Research Station, Ashville, NCGoogle Scholar
- Smith SE, Read DJ (2008) Mycorrhizal symbiosis, 3rd edn. Academic Press, New YorkGoogle Scholar
- Wardle DA (2002) Communities and ecosystems: linking the aboveground and belowground components. Princeton University Press, PrincetonGoogle Scholar