TY - JOUR A1 - Essl, Franz A1 - Dawson, Wayne A1 - Kreft, Holger A1 - Pergl, Jan A1 - Pysek, Petr A1 - van Kleunen, Mark A1 - Weigelt, Patrick A1 - Mang, Thomas A1 - Dullinger, Stefan A1 - Lenzner, Bernd A1 - Moser, Dietmar A1 - Maurel, Noelie A1 - Seebens, Hanno A1 - Stein, Anke A1 - Weber, Ewald A1 - Chatelain, Cyrille A1 - Inderjit, A1 - Genovesi, Piero A1 - Kartesz, John A1 - Morozova, Olga A1 - Nishino, Misako A1 - Nowak, Pauline M. A1 - Pagad, Shyama A1 - Shu, Wen-sheng A1 - Winter, Marten T1 - Drivers of the relative richness of naturalized and invasive plant species on Earth JF - AoB PLANTS N2 - Biological invasions are a defining feature of the Anthropocene, but the factors that determine the spatially uneven distribution of alien plant species are still poorly understood. Here, we present the first global analysis of the effects of biogeographic factors, the physical environment and socio-economy on the richness of naturalized and invasive alien plants. We used generalized linear mixed-effects models and variation partitioning to disentangle the relative importance of individual factors, and, more broadly, of biogeography, physical environment and socio-economy. As measures of the magnitude of permanent anthropogenic additions to the regional species pool and of species with negative environmental impacts, we calculated the relative richness of naturalized (= RRN) and invasive (= RRI) alien plant species numbers adjusted for the number of native species in 838 terrestrial regions. Socio-economic factors (per-capita gross domestic product (GDP), population density, proportion of agricultural land) were more important in explaining RRI (similar to 50 % of the explained variation) than RRN (similar to 40 %). Warm-temperate and (sub)tropical regions have higher RRN than tropical or cooler regions. We found that socio-economic pressures are more relevant for invasive than for naturalized species richness. The expectation that the southern hemisphere is more invaded than the northern hemisphere was confirmed only for RRN on islands, but not for mainland regions nor for RRI. On average, islands have similar to 6-fold RRN, and >3-fold RRI compared to mainland regions. Eighty-two islands (=26 % of all islands) harbour more naturalized alien than native plants. Our findings challenge the widely held expectation that socio-economic pressures are more relevant for plant naturalization than for invasive plants. To meet international biodiversity targets and halt the detrimental consequences of plant invasions, it is essential to disrupt the connection between socio-economic development and plant invasions by improving pathway management, early detection and rapid response. KW - Alien species richness KW - biogeography KW - invasion stages KW - islands KW - pressures KW - vascular plants Y1 - 2019 U6 - https://doi.org/10.1093/aobpla/plz051 SN - 2041-2851 VL - 11 IS - 5 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - van Kleunen, Mark A1 - Essl, Franz A1 - Pergl, Jan A1 - Brundu, Giuseppe A1 - Carboni, Marta A1 - Dullinger, Stefan A1 - Early, Regan A1 - Gonzalez-Moreno, Pablo A1 - Groom, Quentin J. M. A1 - Hulme, Philip E. A1 - Kueffer, Christoph A1 - Kühn, Ingolf A1 - Maguas, Cristina A1 - Maurel, Noelie A1 - Novoa, Ana A1 - Parepa, Madalin A1 - Pysek, Petr A1 - Seebens, Hanno A1 - Tanner, Rob A1 - Touza, Julia A1 - Verbrugge, Laura A1 - Weber, Ewald A1 - Dawson, Wayne A1 - Kreft, Holger A1 - Weigelt, Patrick A1 - Winter, Marten A1 - Klonner, Guenther A1 - Talluto, Matthew V. A1 - Dehnen-Schmutz, Katharina T1 - The changing role of ornamental horticulture in alien plant invasions JF - Biological reviews N2 - The number of alien plants escaping from cultivation into native ecosystems is increasing steadily. We provide an overview of the historical, contemporary and potential future roles of ornamental horticulture in plant invasions. We show that currently at least 75% and 93% of the global naturalised alien flora is grown in domestic and botanical gardens, respectively. Species grown in gardens also have a larger naturalised range than those that are not. After the Middle Ages, particularly in the 18th and 19th centuries, a global trade network in plants emerged. Since then, cultivated alien species also started to appear in the wild more frequently than non-cultivated aliens globally, particularly during the 19th century. Horticulture still plays a prominent role in current plant introduction, and the monetary value of live-plant imports in different parts of the world is steadily increasing. Historically, botanical gardens - an important component of horticulture - played a major role in displaying, cultivating and distributing new plant discoveries. While the role of botanical gardens in the horticultural supply chain has declined, they are still a significant link, with one-third of institutions involved in retail-plant sales and horticultural research. However, botanical gardens have also become more dependent on commercial nurseries as plant sources, particularly in North America. Plants selected for ornamental purposes are not a random selection of the global flora, and some of the plant characteristics promoted through horticulture, such as fast growth, also promote invasion. Efforts to breed non-invasive plant cultivars are still rare. Socio-economical, technological, and environmental changes will lead to novel patterns of plant introductions and invasion opportunities for the species that are already cultivated. We describe the role that horticulture could play in mediating these changes. We identify current research challenges, and call for more research efforts on the past and current role of horticulture in plant invasions. This is required to develop science-based regulatory frameworks to prevent further plant invasions. KW - botanical gardens KW - climate change KW - horticulture KW - naturalised plants KW - ornamental plants KW - pathways KW - plant invasions KW - plant nurseries KW - trade KW - weeds Y1 - 2018 U6 - https://doi.org/10.1111/brv.12402 SN - 1464-7931 SN - 1469-185X VL - 93 IS - 3 SP - 1421 EP - 1437 PB - Wiley CY - Hoboken ER -