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Invasive alien plant species are among the major drivers of change in natural ecosystems; therefore, their eradication or control is a common and effective conservation tool to reverse biodiversity loss. The LIFE LETSGO GIGLIO project was implemented with the objective of controlling the invasion of Carpobrotus spp., among the most threatening invasive alien species in Mediterranean ecosystems, on the Island of Giglio (Tuscan Archipelago, Italy). The management of Carpobrotus spp. was conducted across an area of approximately 33,000 m2 of coastal habitats. The main intervention was conducted during the winter of 2021–2022, primarily through manual removal, with a limited use of mulching sheets. Subsequent years saw the continued removal of seedlings. We monitored the habitats of vegetated sea cliffs and coastal garrigues (both protected under Directive 92/43/EEC), as these were the two habitats most affected by the control actions. A total of 24 permanent plots were sampled annually from 2020 to 2023 in a Before-After-Control-Impact (BACI) design. We analysed the variation pre- and post-removal of Carpobrotus spp. cover and litter and of native plant cover and diversity, as well as the changes in the composition of native plant communities. Our results show that already two years after the main intervention of removal, thus in the short term, the community’s composition shifted considerably towards the pre-invasion set of species. This recovery was also evident in terms of diversity indices, although the impact of Carpobrotus spp. on ecological parameters (mainly soil) favoured nitrophilous species. Furthermore, we highlight the need for yearly removal of Carpobrotus spp. seedlings for the next 5–10 years, in order to continue promoting the recovery of native communities.

Island ecosystems face significant threats from biological invasions due to their unique biomes. In over a quarter of these ecosystems, the number of alien plants surpasses the total count of native ones, leading to notable impacts. This concern is particularly pronounced in the Mediterranean Basin, a globally important hotspot for plant diversity. In line with this, our study aimed to investigate the current distribution of six main alien plant species (Chasmanthe floribunda, Nicotiana glauca, Opuntia ficus-indica, Opuntia stricta, Senecio angulatus, and Zantedeschia aethiopica) on Capraia Island in the Tuscan Archipelago, Italy. We identified invaded vegetation types and N2000 habitats (sensu 92/43/EEC “Habitats” Directive), created a detailed map of the current distribution of these six target species, and analyzed the relationship between their distribution and environmental factors. The six target species were found to be more widespread in areas of the island with higher levels of anthropogenic disturbance, with only O. stricta also spreading into natural habitats. Overall, the invasion covers an area of 71 hectares (3.6% of the island’s surface), of which over 70 hectares are invaded by O. stricta. The habitats most impacted by alien plant invasion include 5330 “Thermo-Mediterranean and pre-desert scrub”, 5320 “Low formations of Euphorbia close to cliffs”, 1240 “Vegetated sea cliffs of the Mediterranean coasts with endemic Limonium spp.”, and 6220* “Pseudo-steppe with grasses and annuals of the Thero-Brachypodietea”, all primarily invaded by O. stricta. Environmental factors most correlated with alien plant distribution include the distance from infrastructure, altitude, and slope aspect.

In this contribution, new data concerning the distribution of vascular flora alien to Italy are presented. It includes new records, confirmations, exclusions, and status changes for Italy or for Italian administrative regions of taxa in the genera Bunias, Calocedrus, Calycanthus, Celosia, Clerodendrum, Convolvulus, Crassula, Cyclamen, Datura, Dicliptera, Eragrostis, Erigeron, Gamochaeta, Gazania, Impatiens, Kolkwitzia, Leucaena, Ludwigia, Medicago, Muscari, Nigella, Oenothera, Opuntia, Paulownia, Petroselinum, Phyllostachys, Physalis, Pseudosasa, Quercus, Reynoutria, Roldana, Saccharum, Sedum, Semiarundinaria, Senecio, Sisyrinchium, Solanum, Sporobolus, Tulipa, Vachellia, Verbena, and Youngia. Nomenclatural and distribution updates published elsewhere are provided as Suppl. material 1.