Conclusion
This study indicates that naturalized species have higher levels of
climatic suitability than cultivated plants that have not naturalized.
However, under a warmer climate, naturalized species are predicted to
lose mostly equal areas with suitable climates as cultivated plants that
did not naturalize yet. Therefore, as climate change progresses, we
might see a turnover in the composition of the naturalized species pool.
The study also reveals that plants with different native origins and
biomes in southern Africa are affected differently. These findings can
assist in identifying cultivated alien plants that pose invasion risks
early and in developing effective management strategies to mitigate
their impacts. Our study highlights that the potential distribution of
the cultivated alien flora in Southern Africa is unlikely to be
amplified by future climate changes. On the contrary, climatically
suitable ranges are projected to shrink, particularly under severe
climate change. The main reason for this finding is that climate change
will likely result in increasingly hot, semi-arid climates in the
region, which will impose strong constraints on the survival of many
plant species; accordingly, many native species are projected to
experience shrinking in climatically suitable space in the region. Thus,
our study highlights that increased climatic suitability for alien
species under climate change, which seems to be the norm in cold and
temperate climates, does not necessarily translate to similar results in
regions of the subtropics.