Evaluating sustainability of Thalictrum petaloideum L., a peripheral population in Korea

Conservation of rare plants, both at the national level and the regional level is important to maintain and conserve plant diversity. This study focused on Thalictrum petaloideum L., an endangered species, for which the Korean peninsula represents the rear edge of the global distribution. T. petaloideum is distributed in isolated populations across four regions. Yeongwol, in Gangwon, had the largest extent of distribution (27,663 m²), the highest number of sub-populations (204), and the highest total population size (87,681), followed by Danyang, in Chungbuk (3970 m²/28/10,285), Samcheok, in Gangwon (3390 m²/13/3871), and Yeosu, in Jeolanam (800 m²/10/816), in descending order. The most stable population structure was found in Yeongwol. Yeosu was found to have the most unstable population structure and the highest risk of extinction. To ensure the sustainability of the population in Yeosu, artificial management of climbing plants, such as Pueraria lobata, is recommended to maintain spaces suitable for regeneration. In Yeongwol, the population is likely to be sustained over a long period. The maintenance of traditional graveyards is necessary to ensure the population’s sustainability. Further studies should assess the genetic characteristics of each regional population for an in-depth characterization of plant distribution on the Korean peninsula.