Pueraria montana var. lobata in Europe
Pueraria montana var. lobata (Fabaceae – A2 List) is a climbing, semi-woody, deciduous, mat-forming, perennial vine native to Asia. It has been introduced into a number of regions worldwide and it invasive in North America, Oceania and the EPPO region (Georgia, Italy, Slovenia and Switzerland). P. montana var. lobata develops rapidly, covering the soil, and can have a negative impact on native vegetation and completely modify the structure of the habitats it invades. The present study analysed the niche dynamics of P. montana var. lobata in Europe to understand whether it has shifted its climatic niche and/or expanded to novel climate(s) after its introduction in Europe. There are three scenarios that may occur in niche dynamics (i) a species occurs under the same climatic conditions occupied in the native area (niche stability), (ii) the species occupies only a subset of climatic conditions occupied in its native range (niche unfilling) (iii) the species colonizes novel climatic conditions unoccupied/not available in the native area (niche expansion). To deduce which of these scenarios best describes the situation of P. montana var. lobata in Europe, distribution data were collected and cleaned (old or uncertain records were removed) and incorporated into a model with 19 bioclimatic variables. Using multivariant statistical analysis, the niche dynamics were estimated from the native and introduced range and then compared between the two ranges. The results show that in Europe, P. montana var. lobata is currently occupying only a subset of the climate of the native range (niche unfilling) and therefore there is potential for further expansion into areas with a suitable climate. In such areas, measures for prevention, early detection and monitoring should be established to avoid further spread and negative impacts.
Sources
Montagnani C, Casazza G, Gentili R, Caronni S, Citterio S (2022) Kudzu in Europe: niche conservatism for a highly invasive plant. Biological Invasions 24, 1017-1032.