Contrasting functional trait syndromes underlay woody alien success in the same ecosystem

TECCO PA; URCELAY C; DÍAZ, S. M.; CABIDO, M; PEREZ HARGUINDEGUY, N.

AUSTRAL ECOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2012

1442-9985

Abstract We performed a comprehensive comparative study of functional traits in coexisting alien and nativewoody species in order to examine the strategies related to resource use and dispersion underlying alien success inmountain Chaco woodlands of central Argentina. Our approach integrated seemingly contrasting pieces of evidencein the region. We specifically assessed whether (i) the ?functional acquisitive trend? previously observed along abroad environmental gradient accounts for woody alien naturalization when considering a single mesic ecosystem;or (ii) more than one trait syndrome is important among alien species, which would be more in line with thecontext-dependent nature of biological invasions at a local scale. Fifteen vegetative and regenerative traits weremeasured on the most common 14 native and 11 alien woody species.We compared the attributes of (i) native andalien species and (ii) between native species and two contrasting groups of alien species identified in the previousanalysis.The overall trait comparison (i) showed that, in terms of vegetative attributes, woody alien species tend tobe on average more acquisitive than native species. However, (ii) two contrasting syndromes were revealed amongalien species: a group of seven deciduous species with acquisitive attributes; and a group of four evergreen speciesshowing markedly more conservative attributes than the first group. The functional attributes of ?conservativealiens? completely overlapped with the range observed for native species, except for an exclusive dispersal phenologyand a stronger tendency to clonal spread. Acquisitive aliens, in turn, proved to be beyond the range of attributes ofnative species, at the acquisitive extreme, as they did in previous comparisons. Despite their importance, generaltrends in plant functional attributes across regions and ecosystems can sometimes obscure trends at more localscales that are nevertheless important for the understanding and management of particular systems. Our studyconcurs with previous general trends when looking at the overall comparison between native and alien species, butunveils contrasting functional strategies among alien species when examining their attributes more closely, evenwithin the same ecosystem.