Plant traits inform predictions of tundra responses to global change.

Contents Summary 1742 I. Introduction 1742 II. The global context of tundra trait variation 1743 III. The current state of knowledge on trait change in the tundra biome 1744 IV. The links between traits and ecosystem functions 1744 V. Future priorities for tundra trait research 1746 VI. Conclusions 1746 References 1747 SUMMARY: In the rapidly warming tundra biome, plant traits provide an essential link between ongoing vegetation change and feedbacks to key ecosystem functions. However, only recently have comprehensive trait data been compiled for tundra species and sites, allowing us to assess key elements of functional responses to global change. In this review, we summarize trait-based research in tundra ecosystems, with a focus on three components: plant trait variation and how it compares with global patterns; shifts in community-level traits in response to environmental change; and the use of traits to understand and predict ecosystem function. Quantifying patterns and trends in plant traits will allow us to better project the consequences of environmental change for the ecology and functioning of tundra ecosystems.