Characteristics of the naturalized flora of Southern Africa largely reflect the non‐random introduction of alien species for cultivation

作者：Ali Omer, Trevor S. Fristoe, Qiang Yang, Noëlie Maurel, Patrick Weigelt, Holger Kreft, Jonas Bleilevens, Wayne Dawson, Franz Essl, Jan Pergl, Petr Pyšek, Mark van Kleunen · 发表于：Ecography · 年份：2021 · DOI：10.1111/ecog.05669 · 被引用次数：23 · 研究领域：Ecology and Vegetation Dynamics Studies、Plant and animal studies、Plant Diversity and Evolution

Biological invasions are one of the most defining features of the Anthropocene. Most studies on biological invasions focus on the later stages of the invasion process, that is after species have already become naturalized. It is frequently overlooked, however, that patterns in origin, phylogeny and traits of naturalized alien species might largely reflect which species have been introduced in the first place. Here, we quantify and assess such introduction biases by analyzing 5317 plant species introduced for cultivation (i.e. primarily as ornamental garden plants) in the 10 countries composing Southern Africa. We show that this cultivated alien flora represents a non‐random subset of the global flora and that this bias at the introduction stage largely contributes to patterns in geographic origin, phylogenetic composition and traits of the naturalized flora. For example, while species from Australasia are, compared to the global flora, disproportionally overrepresented in the naturalized cultivated flora of Southern Africa, this pattern is driven by their higher likelihood of introduction for cultivation. The same is true for the overrepresentation of free‐standing woody species in the naturalized cultivated flora. The strong phylogenetic clustering of the naturalized cultivated flora is also, to a large extent, driven by introduction bias. Although functional traits explained little variation in naturalization success of cultivated plants, naturalization success was more lik...