BIBLIOS

Document type
Journal articles

Document subtype
Full paper

Title
Relationship between recruitment and mother plant vitality in the alien species Acacia cyclops A. Cunn. ex G. Don

Participants in the publication
Emilio Badalamenti (Author)
Luciano Gristina (Author)
Tommaso La Mantia (Author)
Agata Novara (Author)
Salvatore Pasta (Author)
Marco Lauteri (Author)
Patricia Fernandes (Author)
Otilia Correia (Author)
Dep. Biologia Vegetal
CE3C
Cristina Máguas (Author)
Dep. Biologia Vegetal
CE3C
CE3C

Summary
Acacia cyclops is a widespread invader in Mediterranean-climate regions. However, although its naturalization in the Mediterranean Basin dates back only a few years ago, and the invasion process has not been studied hitherto. We investigated seedlings recruitment strategy adopted by A. cyclops in a small island (Lampedusa, Italy) where its natural regeneration was strictly confined under mother plants canopy. Healthy plants (DCP), plants at incipient senescence (SCP) and dead plants (DP) were distinguished according to vitality and canopy status. Living plants were also characterized in relation to leaf C and N isotope composition. Regeneration pattern (seedlings and saplings abundance) was related to the microclimatic differences (soil temperature, air temperature and humidity, soil nutrients, light) observed between canopies and adjacent open areas, and among canopy types. Living canopies ensure milder conditions, reducing extreme values as well as fluctuations between night and day. However, beneath canopies (DP, SCP and DCP) seedlings may benefit from significantly higher soil nutrients content than in the outside, while light availability was much higher under DP. Saplings to seedlings ratio was found to be around 12 under DP, while under SCP it was slightly higher than 1, and just less than 0.5 under DCP. Moreover, saplings growth was significantly higher under SCP and DP, suggesting a prominent role of light in driving seedlings recruitment. Stable isotope analyses of C and N provided ecophysiological information in relation to changes in canopies structure. Thus, while seedling stage appears to be more nutrient-limited, subsequent sapling stage is much more light-limited. Although the species is not yet displaying an invasive spreading on the island, our study provides clear evidence that senescent canopies are better facilitators than healthy in preserving the invasive potential of A. cyclops. This finding suggests some best practices in order to gradually reduce the presence of the alien species within its pristine nuclei of introduction.


Where published
Forest Ecology and Management

Publication Identifiers
ISSN - 0378-1127

Publisher
Elsevier BV



Document Identifiers
DOI - https://doi.org/10.1016/j.foreco.2014.08.016
URL - http://dx.doi.org/10.1016/j.foreco.2014.08.016

Rankings
SCIMAGO Q1 (2016) - 1.662 - Forestry
SCOPUS Q1 (2015) - 1.737 - Forestry

Keywords
Seedling establishment Soil fertility Mediterranean islands Stable isotopes Australian Acacias