Plant invasion risk inside and outside protected areas: Propagule pressure, abiotic and biotic factors definitively matter.

Invasive alien species are among the main global drivers of biodiversity loss posing major challenges to nature conservation and to managers of protected areas. The present study applied a methodological framework that combined invasive Species Distribution Models, based on propagule pressure, abiotic and biotic factors for 14 invasive alien plants of Union concern in Italy, with the local interpretable model-agnostic explanation analysis aiming to map, evaluate and analyse the risk of plant invasions across the country, inside and outside the network of protected areas. Using a hierarchical invasive Species Distribution Model, we explored the combined effect of propagule pressure, abiotic and biotic factors on shaping invasive alien plant occurrence across three biogeographic regions (Alpine, Continental, and Mediterranean) and realms (terrestrial and aquatic) in Italy. We disentangled the role of propagule pressure, abiotic and biotic factors on invasive alien plant distribution and projected invasion risk maps. We compared the risk posed by invasive alien plants inside and outside protected areas. Invasive alien plant distribution varied across biogeographic regions and realms and unevenly threatens protected areas. As an alien's occurrence and risk on a national scale are linked with abiotic factors followed by propagule pressure, their local distribution in protected areas is shaped by propagule pressure and biotic filters. The proposed modelling framework for the assessment of the risk posed by invasive alien plants across spatial scales and under different protection regimes represents an attempt to fill the gap between theory and practice in conservation planning helping to identify scale, site, and species-specific priorities of management, monitoring and control actions. Based on solid theory and on free geographic information, it has great potential for application to wider networks of protected areas in the world and to any invasive alien plant, aiding improved management strategies claimed by the environmental legislation and national and global strategies.

Molecular and Morphometric Update on Italian Salicornia (Chenopodiaceae), with a Focus on the Species S. procumbens s. l.

Salicornia is a highly taxonomically problematic genus due to the reduced morphological observable characters. Ten Eurasian species are currently recognized: S. alpini, S. europaea, S. fruticosa, S. hispanica, S. lagascae, S. perennans, S. perennis, S. persica, S. procumbens, and S. pruinosa. In addition, eleven subspecies are accepted, mainly based on their distribution areas. Along the Venetian coasts and in Sardinia, in the past, an endemic species called S. veneta was recognized, but this name was later synonymized with S. procumbens subsp. procumbens. The aim of the present research is investigating different Italian Salicornia populations by a molecular point of view, using the nuclear ribosomal external transcribed spacer ETS and the plastid psbA-trnH intergenic spacer. A particular focus is on the comparison between Venetian (including those occurring in locus classicus of S. veneta) and Sardinian S. procumbens and other Italian populations of this species. The molecular analyses based on the plastid marker highlight that the Italian S. procumbens populations form two well distinct groups. In particular, some of the Venetian (Locus classicus of S. veneta) and all the Sardinian specimens are genetically distinct (=plastid haplotype 1) from the other investigated populations (=plastid haplotype 2). This indicates that the psbA-trnH haplotype 1 glassworts represent a distinct entity, which we suppose to coincide with the former S. veneta. Therefore, we suggest to recognize this taxonomic entity at the subspecies rank, as S. procumbens subsp. veneta comb. and stat. nov. However, contrary to the results found with the plastid psbA-trnH intergenic spacer, the ETS locus does not show a separation into two distinct clades for S. procumbens, probably due to a different evolution of the two loci. Nevertheless, in the ETS phylogenetic reconstruction, the Sardinian specimens (=ribotypes 2 and 3) are placed, together with a Moroccan sample, in a subclade separated from all the other S. procumbens. These results suggest that the Sardinian populations can represent a subspecies/incipient speciation process, probably due to geographic isolation. In the light of this, morphometric analyses (k-means, MANOVA, PCA, DA, and Box-Plot) have been carried out on the Sardinian and Venetian populations to verify if this distinction is detectable also by a morphological point of view. The morphometric analyses highlight the existence of two groups, concerning both the nuclear and plastid trees. Six characters were found to be diagnostic.

Taxonomy Complexity of Some Tyrrhenian Endemic Limonium Species Belonging to L. multiforme Group (Plumbaginaceae): New Insights from Molecular and Morphometric Analyses.

The delimitation of Limonium taxa is highly complicated due to hybridization, polyploidy, and apomixis. Many "microspecies" were described and aggregated into groups, most of which are still poorly known from both molecular and morphological points of view. The aim of this study is to investigate four endemic species from the Tyrrhenian coast of central Italy and the Ponziane Archipelago belonging to the L. multiforme group (L. amynclaeum, L. circaei, L. pandatariae, and L. pontium) by means of molecular and morphometric analyses. Molecular data by sequencing ITS and three plastid markers and morphometric data highlight new information about the taxonomy of these taxa so as to reduce them into a single specific entity. In fact, the better taxonomic choice is to consider the populations studied as part of a single species, i.e., Limonium pontium. Three subspecies are recognized, i.e., subsp. pontium [= L. circaei = L. amynclaeum; from Circeo to Gianola localities (excluding Terracina) and from islands Ponza, Palmarola, Zannone, and Santo Stefano], subsp. pandatariae comb. et stat. nov. (from island of Ventotene), and subsp. terracinense subsp. nov. (from Terracina).

The segetal flora of Italy: an occurrence dataset from relevés in winter cereals and allied crop types.

The segetal flora of winter crops includes mostly native or archaeophyte annual species that are often strong specialists of their habitats. Threatened by the intensification of agriculture, segetal flora is particularly valuable from a perspective of biodiversity conservation and evolution. Moreover, it contributes to maintain biodiversity in agroecosystems and provides several ecosystem services. The dataset here described was set up to provide the first inventory of the segetal flora of Italian winter cereal crops and allied crop types, the latter including flax and autumn-sown legumes. It includes 24,676 georeferenced occurrence data deriving from 1,240 floristic and phytosociological relevés. The data were collected from the greater part of Italian territory, in a temporal range spanning from 1946 to 2018.