Distribution and pathways of introduction of invasive alien plant species in Romania

Abstract

Biological invasions are one of the main drivers of modern human-induced species losses. Research on the distribution of alien species and their pathways of introduction is essential for understanding and tackling the invasion process. A comprehensive overview on invasive alien plant (IAP) species in Romania is lacking. With this paper, we aim to contribute to filling this gap and to provide a visualization of national patterns regarding plant species invasions, geographical origins and pathways of introductions. Based on plant species occurrence records in the published literature and herbaria we compiled a national database of 102 invasive and potentially invasive alien plant species. We georeferenced 42776 IAP species occurrences and performed an analysis of their spatial patterns. The spatial analyses revealed a biased sampling, with clear hotspots of increased sampling efforts around urban areas. We used chord diagrams to visualize the pathway of introduction and geographical origins of the IAP species, which revealed that species in Romania originate mainly in North and Central America, while the dominant pathway of plant introduction was horticulture. Our results provide an important baseline in drafting management and action plans, as invasive alien plant species represent a priority for the European Union through the Biodiversity Strategy for 2030, and a good starting point for various analyses as the database is further developed and regularly updated.

The TOP-100 most dangerous invasive alien species in Northern Eurasia: invasion trends and species distribution modelling

“…Nevertheless, a non-linear upward trend in the dynamics of the total number of invaded species has been observed only since the late 1940s showing three peaks during 1946-1962, 1970-1981 and 2000-2014. Since 1946, the number of recorded IAS has doubled, and further increases are expected. A similar rapid growth in the number of invasive species has been documented in other countries since the second half of the 20 th century, including Croatia (Nikolić et al 2013), East Africa (Witt et al 2018) and Romania (Sirbu et al 2022). The above studies show that peaks in the numbers of newly introduced species occurred in Romania (Sirbu et al 2022) and Croatia (Nikolić et al 2013) in the 1950s, while in East Africa (Witt et al 2018) and Russia, the maximum numbers of introduced species declined during 1940s-1960s.…”

“…A similar rapid growth in the number of invasive species has been documented in other countries since the second half of the 20 th century, including Croatia (Nikolić et al 2013), East Africa (Witt et al 2018) and Romania (Sirbu et al 2022). The above studies show that peaks in the numbers of newly introduced species occurred in Romania (Sirbu et al 2022) and Croatia (Nikolić et al 2013) in the 1950s, while in East Africa (Witt et al 2018) and Russia, the maximum numbers of introduced species declined during 1940s-1960s. Common factors that facilitated the increase in introductions in the second half of the 20 th century in Russia included increases in traffic flows (Kalabekov 2020) and interstate communications.…”

Methods of Including Invasive Species Research in Urban Planning – A Case Study on <i>Ailanthus altissima</i>

“…Most of the species from the green areas within Bucharest, sector 4 included, are indigenous species, but there are non-native species, too. These latter species were introduced in the green urban areas from sector 4 for decorative purposes [20], their possible future impact being unknown. Therefore, the new species that have been used to improve the urban landscape proved to be invasive species, which has been the case with Ailanthus altissima.…”

Potential of biological invasion for carbon sequestration in a protected area: the case of the Limbe Botanic Garden (LBG) forest, Cameroon

“…6 Introductions of invasive alien species are, to date, considered to be an important component of human-induced global change. 7 In some cases, this leads to species extinctions. 8 In Cameroon, to date, around fifty exotic species are listed as invasive.…”