Kudzu in Europe: niche conservatism for a highly invasive plant

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.

Climatic envelopes of the genus Lacerta Linnaeus, 1758 in Türkiye: an application of ecological niche modeling

Six species belonging to the genus Lacerta live in Türkiye. In this study, both present and future potential distribution maps were created based on occurrence data and climatic variables for these six species. Two scenarios for future projections (shared socioeconomic pathways, SSPs,: 245 and 585) and two timeframes (2041-2060 and 2081-2100) were used. The present and future potential distributions of these species were compared. As a result, it was predicted that the distribution ranges in the six species will expand in the future, and this expansion has revealed new environments.

Cytogeography of Naturalized Solidago canadensis Populations in Europe

Autopolyploidization has driven the successful invasion of Solidago canadensis in East Asia. However, it was believed that only diploid S. canadensis invaded Europe, whereas polyploids never did. Here, molecular identification, ploidy level, and morphological traits of ten S. canadensis populations collected in Europe were compared with previously identified S. canadensis populations from other continents and S. altissima populations. Furthermore, the ploidy-driven geographical differentiation pattern of S. canadensis in different continents was investigated. All ten European populations were identified as S. canadensis with five diploid and five hexaploid populations. Significant differences in morphological traits existed among diploids and polyploids (tetraploids and hexaploids), rather than between polyploids from different introduced ranges and between S. altissima and polyploidy S. canadensis. The invasive hexaploids and diploids had few differences in latitudinal distributions in Europe, which was similar to the native range but different from a distinct climate-niche differentiation in Asia. This may be attributed to the bigger difference in climate between Asia and Europe and North America. The morphological and molecular evidences proved the invasion of polyploid S. canadensis in Europe and suggest that S. altissima may be merged into a complex of S. canadensis species. Our study may be concluded that geographical and ecological niche differentiation of an invasive plant driven by ploidy depends on the degree of difference in the environmental factors between the introduced and native range, which provides new insight into the invasive mechanism.

Appressed, directed and silicified trichomes of the kudzu climbing vine

Kudzu (Pueraria montana var. lobata) is becoming one of the most prevalent climbing vines in urban forests. Here, surface characteristics of kudzu leaves and stems are investigated using field-emission scanning electron microscopy and X-ray microanalysis. The leaf and stem surfaces were characterized by different types of trichomes. No adhesive pads, modified hooks or tendrils were found on kudzu vines. Trichomes on the leaves and stems of kudzu could be categorized into (i) complex bulbous glandular trichomes and (ii) needle-shaped nonglandular trichomes (NSNGTs). Two morphotypes of the nonglandular trichomes were present on the stems: (i) long hairy nonglandular trichomes and (ii) short NSNGTs. The leaf trichomes were appressed and oriented in an uphill direction, whereas the stem trichomes were appressed and oriented in a downhill direction. This opposite trichome orientation appears to facilitate climbing and prohibits slipping of kudzu vines through differential friction between the plants and the kudzu vines. X-ray microanalysis revealed a distinct accumulation of silicon in the leaf and stem trichomes. These results suggest that appressed, directed and silicified trichomes may contribute to the twining behavior of kudzu vines.