Snow addition and warming impacts on arctic leaf anatomy and gas exchange

Climatic changes can result in modified leaf anatomy and gas exchange in arctic plants. In a one-year-old field experiment in Greenland, Schollert et al. investigate the effects of increased snow depth and warming on leaf anatomy, biogenic volatile organic compound (BVOC) emissions and CO₂ exchange for the common arctic shrubs Betula nana and Empetrum nigrum ssp. hermaphroditum.

Additional snow depth affected the leaf anatomy by increasing the glandular trichome density in B. nana and modifying the mesophyll of E. hermaphroditum. Passive summer warming in open-top chambers thickened the epidermis of B. nana, while increasing the glandular trichome density and reducing the palisade:spongy mesophyll ratio in E. hermaphroditum. The modifications in leaf anatomy suggest a linkage between responses in leaf anatomy, BVOC emissions and CO₂ gas exchange, highlighting the ecological importance of monitoring changes in arctic winter precipitation.