caa a22 4500 463168259 CHVBK 20180406164805.0 cr unu---uuuuu 170326e20070601xx s 000 0 eng 10.1007/s10530-006-9050-4 doi (NATIONALLICENCE)springer-10.1007/s10530-006-9050-4 Elton's hypothesis revisited: an experimental test using cogongrass [Elektronische Daten] [A. Collins, S. Jose, P. Daneshgar, C. Ramsey] In the 1950s Charles Elton hypothesized that more diverse communities should be less susceptible to invasion by exotic species (biodiversity-invasibility hypothesis). The biodiversity-invasibility hypothesis postulates that species-rich communities are less vulnerable to invasion because vacant niches are less common and the intensity of interspecific competition is more severe. Field studies were conducted at two sites, a logged site and an unlogged site in Santa Rosa County, Florida, U.S.A, to test Elton's hypothesis using cogongrass (Imperata cylindrica), a non-indigenous grass invading large areas of the Southeastern United States. The logged site was under 17-year-old loblolly pine prior to clear cutting. The unlogged site, a longleaf pine forest, was at the Blackwater River State Forest. Both the logged site and unlogged site showed no significant relationship between the rate of cogongrass spread and native plant species richness, functional richness, and cover of the invaded community. Increased species or functional richness may increase the use of resources; however, the extensive rhizome/root network possessed by cogongrass and its ability to thrive under shade may allow for its persistence in a diverse community. The results from both the logged and unlogged sites do not support the general hypothesis of Elton that invasion resistance and compositional stability increase with diversity. Biodiversity does not appear to be an important factor for cogongrass invasion in the southern United States. Extrinsic factors in this study prevent the ability to draw a defined causal relationship between native plant diversity and invasibility. Underlying reasons for why no relationship was observed may be simply due to the tremendous competitive ability of cogongrass or the narrow range of species richness, functional richness and cover observed in our study. Springer Science+Business Media, Inc., 2006 Biodiversity nationallicence Cogongrass nationallicence Exotic nationallicence Functional Diversity nationallicence Imperata cylindrica nationallicence Invasibility nationallicence Collins A. School of Forest Resources and Conservation, University of Florida, 351 Newins-Ziegler Hall, P.O. Box 110410, 32611, Gainesville, FL, USA aut Jose S. School of Forest Resources and Conservation, University of Florida, 351 Newins-Ziegler Hall, P.O. Box 110410, 32611, Gainesville, FL, USA aut Daneshgar P. School of Forest Resources and Conservation, University of Florida, 351 Newins-Ziegler Hall, P.O. Box 110410, 32611, Gainesville, FL, USA aut Ramsey C. Animal and Plant Health Inspection Service, United States Department of Agriculture, Fort Collins, CO, USA aut Biological Invasions Kluwer Academic Publishers 9/4(2007-06-01), 433-443 1387-3547 9:4<433 2007 9 10530 https://doi.org/10.1007/s10530-006-9050-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10530-006-9050-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Collins A. School of Forest Resources and Conservation, University of Florida, 351 Newins-Ziegler Hall, P.O. Box 110410, 32611, Gainesville, FL, USA aut NATIONALLICENCE 700 1- Jose S. School of Forest Resources and Conservation, University of Florida, 351 Newins-Ziegler Hall, P.O. Box 110410, 32611, Gainesville, FL, USA aut NATIONALLICENCE 700 1- Daneshgar P. School of Forest Resources and Conservation, University of Florida, 351 Newins-Ziegler Hall, P.O. Box 110410, 32611, Gainesville, FL, USA aut NATIONALLICENCE 700 1- Ramsey C. Animal and Plant Health Inspection Service, United States Department of Agriculture, Fort Collins, CO, USA aut NATIONALLICENCE 773 0- Biological Invasions Kluwer Academic Publishers 9/4(2007-06-01), 433-443 1387-3547 9:4<433 2007 9 10530 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer