LAUSR

Abstract The Korean Peninsula is the southern limit of the distribution of Picea jezoensis (Siebold et Zucc.) Carriere, where it occurs only on isolated subalpine mountain tops in South Korea. Global warming is altering habitat environments, threatening the survival of P. jezoensis. This study investigated the seed germination, seedling establishment, and seedling mortality of P. jezoensis on different forest floor substrates (woody debris [WD], litter, and soil from a P. jezoensis habitat on Mt. Gyebang), together with horticultural sand, under control (mimicking habitat condition: day 22.3 °C/night 9.4 °C) and elevated (26.6 °C/13.7 °C) air temperatures to determine the effects of an increase in temperature on P. jezoensis regeneration. Seed germination did not differ significantly between the control and elevated temperature conditions on all substrates. Yet, seedling mortality increased by more than 1.4 times under elevated temperature compared to controls on all substrates. Among the four substrates, WD and litter respectively exhibited the lowest (15.6%) and highest (50%) seedling mortality for P. jezoensis under control conditions, with respective significant increases of 53% and 77% seedling mortality under elevated temperature (p