Trait data set

Abstract Identifying which functional traits distinguish species’ responses to climate change is essential for estimating future species composition and ecosystem function. Previous studies on the trait-based approach have attempted to explain plant performance using either aboveground or belowground traits at either the organ or the whole-plant level. To understand the species-specific responses to climate change, however, it is necessary to examine various traits simultaneously and comprehensively, including organ- and whole-plant-level traits both aboveground and belowground, within the same study. Changes in species’ abundance have been recorded in the alpine snow-meadow of the Taisetsu mountains, northern Japan, over a 40-year period. We examined whether 26 functional traits differed between the species exhibiting an increasing trend and those exhibiting a decreasing trend to understand the underlying mechanism that differentiates the species’ responses to climate change. We found that the increasing species have larger rhizomes and longer and thinner fine roots, suggesting that drought tolerance may separate the alpine species’ responses to climate warming. Our study demonstrates that belowground WP traits, as well as belowground OR traits, play decisive roles in distinguishing the species' responses to climate change. Our findings also indicate that belowground traits may provide better predictions of alpine species abundance in response to climate warming than aboveground traits. Thus, our study suggests that understanding belowground traits at the whole-plant level may contribute to more accurate and efficient predictions of the responses of alpine plants to climate change.