Global Ecology and Conservation (Jan 2023)
Alien ornamental plant species cultivated in Taizhou, southeastern China, may experience greater range expansions than native species under future climates
Abstract
Ornamental horticulture constitutes a major pathway of alien plant species introductions into different biogeographic regions globally. Studies increasingly suggest that climate change may favour invasive spread of many ornamental species, although the extent to which this may occur in different biomes globally remains unclear. Having a predictive understanding of how future climates may affect geographic distribution of alien plants will inform control of future invasions by alien flora. Here, we explored whether species distribution models (SDMs) that account for plant species' invasion history and life-history characteristics including reproduction mode and life cycle may potentially be used to develop simple tools to screen alien flora for their invasion potential. We took an inventory of ornamental plant species that are cultivated in Taizhou metropolitan area, southeastern China. We then ran SDMs through an ensemble modeling framework in BIOMOD2 to project distribution of the plant species under historical climate for the period 1979-2013 and four climate change scenarios BCC-CSM2-MR/SSP1–2.6, BCC-CSM2-MR/SSP5–8.5, MIROC6/SSP1–2.6, and MIROC6/SSP5–8.5 for the period 2021–2040. We addressed the following questions: (1) What are the relative proportions of alien and native ornamental plant species that are cultivated in Taizhou? (2) Do alien species with a history of invasion somewhere in the world have a greater climate suitability than native species in China? (3) Do the plant species' life-history characteristics correlate significantly with their projected climate suitability in China? A total of 277 alien and native ornamental garden plant species were identified. Out of these, 209 species had naturalized somewhere in the world including China. Out of the 209 naturalized species, 134 species were native while 75 species were alien to China. Overall, both the alien and native species were projected to find more suitable climatic space regionally within Taizhou and southeastern China than across the entire mainland China. Reproduction mode, life cycle, and invasion history of the plant species were significantly correlated with climatic suitability of the species under some future climate scenarios. Moreover, alien species will generally experience stronger range expansions than native species under future climate change scenarios. The alien species that are projected to experience range expansions under future climates should be prioritized for monitoring to prevent their invasive spread.
