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Abstract Urban areas are foci for the introduction of non‐native plant species, and they often act as launching sites for invasions into the wider environment. Although interest in biological invasions in urban areas is growing rapidly, and the extent and complexity of problems associated with invasions in these systems have increased, data on the composition and numbers of non‐native plants in urbanized areas remain scattered and idiosyncratic.We assembled data from multiple sources to create the Global Urban Biological Invasions Compendium (GUBIC) for vascular plants representing 553 urban centres from 61 countries across every continent except Antarctica.The GUBIC repository includes 8140 non‐native plant species from 253 families. The number of urban centres in which these non‐native species occurred had a log‐normal distribution, with 65.2% of non‐native species occurring in fewer than 10 urban centres.Practical implications: The dataset has wider applications for urban ecology, invasion biology, macroecology, conservation, urban planning and sustainability. We hope this dataset will stimulate future research in invasion ecology related to the diversity and distributional patterns of non‐native flora across urban centres worldwide. Further, this information should aid the early detection and risk assessment of potential invasive species, inform policy development and assist in setting management priorities.
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Plant regulatory lists in the United States are reactive and inconsistent
Abstract Global invasive species introductions are rising, necessitating coordinated regulatory strategies within and across national borders. Although states and nations address their unique priorities using plant regulations, these regulations are most likely to reduce invasive plant introduction and spread if they are consistently enacted across political borders and proactively restrict spread early in the invasion process. Further, a unified regulatory landscape is particularly important given the imminent range infilling and large‐scale climate‐driven range shifts of invasive species.In the United States, federal and state regulations restrict the introduction and spread of several hundred invasive and noxious plant taxa in an effort to reduce their negative impacts. Using plant regulations for the lower 48 United States, we assessed consistency among regulated taxa based on similarities in adjacent states’ regulatory lists. We assessed proactivity by comparing regulatory lists to plants’ current and potential distributions given occurrence records and species distribution models under climate change.States regulate from 0 to 162 plant taxa, with an average of only 16.8% overlap of regulated taxa between adjacent states. Up to 137 plants may be present but unregulated in a state, and only 110 of 553 listed taxa were regulated in one or more states where they were not yet present. However, 36 states listed at least one taxon proactively (regulated but not present in the state). Of the 48 proactively listed taxa with species distribution models, we identified 41 cases (38 species in 21 states) where listing was ‘climate proactive’ (regulated, not present and where climate could be suitable for establishment by mid‐century).Policy implications. US plant regulatory lists were inconsistent across borders and reactive to climate change. However, most states regulate at least one plant taxa prior to its introduction, suggesting that a more proactive approach is possible under existing regulations. Coordination across borders is imperative given gaps in regional defences against invasion and projected invasive plant range shifts under climate change. We suggest that subnational, national and international governing bodies evaluate their plant regulatory lists for consistency and proactivity, as it is paramount for preventing the next wave of plant invasions.
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- Award ID(s):
- 1740267
- PAR ID:
- 10449840
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Applied Ecology
- Volume:
- 58
- Issue:
- 9
- ISSN:
- 0021-8901
- Page Range / eLocation ID:
- p. 1957-1966
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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