Potential distribution of two Ambrosia species in China under projected climate change

Summary The invasion of A mbrosia artemisiifolia and A mbrosia trifida from their native range to occupy large areas in C hina has raised considerable concern. Using the maximum entropy ( M axent) method, we developed models for each A mbrosia species, based on occurrence records from both native ranges ( N orth A merica) and their invaded ranges (e.g. northern and south‐western E urope) to predict the availability and distribution of suitable habitats for these two species in C hina. For each species, we also assessed potential shifts in habitat suitability for the year 2050, using three general circulation models ( GCM s) and two emission scenarios. Elevation and average mean precipitation in O ctober contributed most to model development for both species. Potential distribution projections under future climatic change scenarios suggested an averaged percentage of suitable area (2.21%) and habitat gain (1.49%) in A . artemisiifolia distribution, with further expansion to environmentally favourable locations in south‐east coastal regions, northern T aiwan and the B eijing– T ianjin– T angshan area in northern C hina. Future predicted percentage of suitable area for A . trifida was 0.03% with a very limited suitable habitat gain of <1% although this species had the potential to continue to spread in northern C hina. Our findings suggest that management priorities should be focused on A . artemisiifolia , whilst effective control strategies for A . trifida may be optimised by concentrating efforts on those relatively fewer regions of C hina where the species is currently abundant.