Phytogeographic study on the Holocene hypsithermal relict plant populations in the Korean peninsula

Abstract

The Holocene Hypsithermal Interval(or climatic optimum) was the warmest post-glacial period: temperatures rose to as much as 1-4 o C above present temperatures. We hypothesize that southern plants expanded northward and upward during the Hypsithermal Interval. The Hypsithermal relict populations are defined as populations which distribute mainly in Is. Cheju and Southern subregions and have populations of short-distance dispersion separated by more than 100 km from the nearest distribution. The Hypsithermal relict species were identified and their distributions were mapped based on botanical floras and checklist, herbaria specimens, ecological studies, and field surveys of selected species. Evaluation of the hypothesis was based on reviews of published pollen stratigraphic and paleoecological studies. The results showed that the Holocene Hypsithermal relicts such as Corylopsis coreana Uyeki, Carpinus turczaninowii Hance, Stewartia koreana Nakai ex Rehder were expanded northward during the Holocene Hypsithermal Interval.

Redefining floristic zones in the Korean Peninsula using high‐resolution georeferenced specimen data and self‐organizing maps

“…The historical floristic zones of the Korean Peninsula were constructed to broadly reflect a combination of climatic factors and plant distribution patterns, and showed a banded, near-planar shape (Appendix S1) (Lee & Yim, 1978). Our SOM results, revealing four statistically significant Stewartia koreana and Lindera sericea) can be found growing in the medium-and high-altitude areas of Zone II (Kim et al, 2014). There is almost no highland agriculture in this zone, but some timber production occurs (mostly Larix kaempferi), and the zone is adjacent to numerous large cities.…”

“…The Korean Peninsula, which is topographically composed of around 80% mountains, is characterized by a backbone mountain range (the Baekdudaegan Mountains) running from north to south with sub‐ranges branching off. The major mountains (≥1,000 m above sea level) are considered a single glacial refugium based on altitude rather than latitude, and they have a mixture of boreal and temperate flora (Chung, López‐Pujol, & Chung, 2017; Chung et al., 2018; Kim, Chung, Kim, Kim, & Lee, 2014). The botanical importance of peninsulas and mountainous regions is well established because of their topographic characteristics (Médail & Diadema, 2009).…”

Redefining floristic zones on the Korean Peninsula using high-resolution georeferenced specimen data and self-organizing maps (SOMs)

“…Through the same historical geographical processes as Zone I, this zone shows the remnants of the influence of the periglacial environment in the southern Korean Peninsula. In addition, trees that are mostly distributed in warmer or maritime climates (e.g., Stewartia koreana and Lindera sericea ) can be found growing in the medium and high altitude areas of Zone II (Kim et al, 2014). There is almost no highland agriculture in this zone, but some timber production occurs (mostly Larix kaempferi ), and the zone is adjacent to numerous large cities.…”

“…This is the background for the current plant diversity and species composition on the peninsula (Appendix A2). Thus, through repeated historical geographical processes, such as periglacial climates, the Korean Peninsula has acted as a geographical and biological corridor, with a mixture of highand low-latitude plants, which has produced the present-day spatial distribution of biodiversity (Chang et al, 2016;Chung et al, 2017a;Chung et al, 2017b;Kim et al, 2014;Kim et al, 2005;Kong et al, 2019).…”

“…The major mountains ([? ]1000 m above sea level) are considered to be a single glacial refugium based on altitude rather than latitude, and they have a mixture of boreal and temperate flora (Chung et al, 2017b;Chung et al, 2018;Kim et al, 2014). The botanical importance of peninsulas and mountainous regions is well established because of their topographic characteristics (Medail and Diadema, 2009).…”