Changes in stand structure and biomass increment in a warm temperate forest at a long-term ecological research site in Korea over 17 years

Changes in stand biomass, stem density, mortality and recruitment were monitored from 2000 to 2016 at 5- or 6-year intervals of Mt. Geumsan (GMS). The GMS had 34 woody plant species and 2698 living stems (DBH ≥ 2 cm) ha −1 in 2016, with an increase in biomass from 233.80 ton ha −1 in 2000 to 282.15 ton ha −1 in 2016. The dominant species in the canopy layer was Quercus serrata, while Chamaecyparis obtusa was the dominant species in the subtree layer. During the 17 years, the biomass of Q. serrata increased from 156.35 to 198.40 ton ha −1 , while the stem density of Q. serrata declined from 395 to 268 stems ha −1 . In addition, the biomass of C. obtusa increased from 12.70 to 24.09 ton ha −1 , and also the stem density of C. obtusa increased from 722 to 898 stems ha −1 . The forest structure of GMS is expected to maintain dominance of Q. serrata, and C. obtusa is increasing. Therefore, GMS was a natural broad-leaved forest composed of Q. serrata, but natural broad-leaved species at the site are declining due to the regeneration and growth of C. obtusa, which is relatively shade-tolerant compared to other species.