Trait variation and potential climate sensitivity of endemic alpine plants in Aotearoa

For alpine plants to persist under climate change they must be able to adapt to new temperature and water regimes in their current ranges or migrate upslope to track temperatures within their tolerances. In addition, climate change is predicted to move across landscapes at rates that exceed those of dispersal in many specialists and endemic alpine species5. These multiple and interactive drivers of environmental change make it difficult to predict future species ranges from environmental data alone. Plant trait plasticity may provide a mechanism for species to persist in the face of rapid environmental change.

In this study, I aimed to quantify variation in phenotypic plasticity in four endemic alpine species at local and bioregional scales, in order to make predictions about their potential to respond to climate change. Eight trait variables associated with plant life history strategies and resource acquisition were measured, and permutation tests used to detect significant variation in trait values with elevation. Plasticity was seen in all species, indicating all may have some ‘bandwidth’ to able to adapt with rapidly changing mountain environments. I then discussed the resulting trait–environment relationships and what they may mean in regard species persistence under global climate change.