“…Most previous studies focused on extreme conditions, such as tree kill areas associated with extraordinarily high CO 2 emissions at Mammoth Mountain, CA (USA; Biondi and Fessenden, 1999;Farrar et al, 1995;Sorey et al, 1998). However, the nonlethal effects of cold volcanic CO 2 emissions -away from the peak emission zones, but still in the theorized fertilization window -have received little attention and could offer a new approach for studying the effects of elevated CO 2 on ecosystems (Cawse- Nicholson et al, 2018;Vodnik et al, 2018). The broad flanks of active volcanoes experience diffuse emissions of excess CO 2 because the underlying active magma bodies continuously release gas, dominated by CO 2 transported to the surface along fault lines (Chiodini et al, 1998;Dietrich et al, 2016;Farrar et al, 1995).…”