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Background The Northern Hemisphere forest ecosystem is a major sink for atmospheric carbon dioxide, and the subalpine zone stores large amounts of carbon; however, their magnitude and distribution of stored carbon are still unclear. Results To clarify the carbon distribution and carbon budget in the subalpine zone at volcanic Jeju Island, Korea, we report the C stock and changes therein owing to vegetation form, litter production, forest floor, and soil, and soil respiration between 2014 and 2016, for three subalpine forest ecosystems, namely, Abies koreana forest, Taxus cuspidata forest, and Juniperus chinensis var. sargentii forest. Organic carbon distribution of vegetation and NPP were bigger in the A. koreana forest than in the other two forests. However, the amount of soil organic carbon distribution was the highest in the J. chinensis var. sargentii forest. Compared to the amount of organic carbon distribution (AOCD) of aboveground vegetation (57.15 t C ha−1) on the subalpine-alpine forest in India, AOCD of vegetation in the subalpine forest in Mt. Halla was below 50%, but AOCD of soil in Mt. Halla was higher. We also compared our results of organic carbon budget in subalpine forest at volcanic island with data synthesized from subalpine forests in various countries. Conclusions The subalpine forest is a carbon reservoir that stores a large amount of organic carbon in the forest soils and is expected to provide a high level of ecosystem services.

The complete chloroplast (cp) genome sequence of Myuroclada maximowiczii (GenBank accession number MT726030), a species of moss in the Brachytheciaceae family, was determined using Illumina HiSeq paired-end sequencing data. The total size of the cp genome was 124,607 bp. The genome contained a large single-copy (LSC) region of 86,684 bp, a small single-copy (SSC) region of 18,483 bp, and a pair of identical inverted repeat regions (IRs) of 9,720 bp. The genome contained 82 protein-coding genes, 36 transfer RNA (tRNA) genes, and eight ribosomal RNA (rRNA) genes. The cp genome presented here will provide useful information for future phylogenetic and evolutionary studies of Myuroclada species.

Background Standing biomass, litter production, rate of litter decomposition, amount of litter on forest floor, and amount of soil organic carbon distribution were investigated from March 2016 to November 2018 in order to evaluate the ecosystem value through organic carbon distribution in the Pinus densiflora forest at Namsan, Seoul Metropolitan City. Results The amount of organic carbon in the Pinus densiflora forest was 261.09 ton C ha−1 during the research period, and fixed organic carbon in plant through net photosynthesis was 3.2 ton C ha−1 year−1. The organic carbon in plant was 62.77 ton C ha−1 (24.04%), in litter on the forest floor was 3.65 ton C ha−1 (1.40%), and in soil was 194.67 ton C ha−1 (74.56%). The value of plant, litter on forest floor, and soil organic carbon distribution were each 6,277,000 won ha−1, 365,000 won ha−1, and 19,467,000 won ha−1. The value per ton of fixed organic carbon in plant through net photosynthesis was 320,000 won ha−1 year−1 and the value of ecosystem services stored in carbon in the Namsan forest ecosystem was about 26.1 million won ha−1 for 3 years. Conclusions The results of this study suggest that the pine forests of Namsan rapidly decompose leaves due to the high atmospheric temperature and accumulate a large amount of organic carbon in the soil to provide climate control regulatory service function.

This study investigated the temporal variation in soil CO2 efflux and its relationship with soil temperature and precipitation in the Quercus glauca and Abies koreana forests in Jeju Island, South Korea, from August 2010 to December 2012. Q. glauca and A. koreana forests are typical vegetation of warm-temperate evergreen forest zone and sub-alpine coniferous forest zone, respectively, in Jeju island. The mean soil CO2 efflux of Q. glauca forest was 0.7 g CO2 m−2 h−1 at 14.3 °C and that of A. koreana forest was 0.4 g CO2 m−2 h−1 at 6.8 °C. The cumulative annual soil CO2 efflux of Q. glauca and A. koreana forests was 54.2 and 34.2 t CO2 ha−1, respectively. Total accumulated soil carbon efflux in Q. glauca and A. koreana forests was 29.5 and 18.7 t C ha−1 for 2 years, respectively. The relationship between soil CO2 efflux and soil temperate at 10 cm depth was highly significant in the Q. glauca (r 2 = 0.853) and A. koreana forests (r 2 = 0.842). Soil temperature was the main controlling factor over CO2 efflux during most of the study period. Also, precipitation may affect soil CO2 efflux that appeared to be an important factor controlling the efflux rate. Soil CO2 efflux was affected by soil temperature as the dominant control and moisture as the limiting factor. The difference of soil CO2 efflux between of Q. glauca and A. koreana forests was induced by soil temperature to altitude and regional precipitation.

The sprouts of oak species play an important role in maintaining the oak community in a disturbed environment. In this study, we cut 1-year-old oak in three times during the 3 years and measured the sprout responses to know sprouting ability of six deciduous oaks in Korea. Oak sprouts have appeared in spring and fall, and some of the sprouts had lifespan as short as a month. As the number of cutting increases, sprout number of Quercus acutissima increased whereas the other oak species decreased or died. The average number of sprouts over the 3 years was from 1.4 (Quercus mongolica) to 2.2 (Q. acutissima) per individual. Quercus serrata died after the second cutting, and Quercus dentata died after the third cutting. So, the two species have the lowest sprouting ability among six oak species. The sprouts grew actively during fall and slowly in summer. The sprout length during the 3 years was in the following descending order: Q. acutissima, Quercus aliena, Q. dentata, and Q. mongolica. Sprout of Q. acutissima and Q. aliena generated steadily over the 3 years, and sprout of Quercus variabilis and Q. mongolica was changed by year. After the 3 years, the number of sprouts increased only in Q. acutissima but sprout number of the other five oak species decreased. The sprout length of Q. acutissima, Q. aliena, and Q. variabilis increased, but sprout length of the other three oak species decreased. The average survival rate of saplings over the 3 years was in the following descending order: Q. acutissima, Q. aliena, Q. variabilis, and Q. mongolica. As a result, the sprouting ability of Q. acutissima was the highest. Such level of sprouting ability may be the evidence of how Q. acutissima community exists as a dominant species in a disturbed environment in lowlands of Korea peninsula.

In order to investigate organic carbon distribution, carbon budget, and cycling of the subalpine forest, we studied biomass, organic carbon distribution, litter production, forest floor litter, accumulated soil organic carbon, and soil respiration in Taxus cuspidata forest in Halla National Park from February 2012 to November 2013. Biomass was calculated by using allometric equation and the value was converted to CO2 stocks. The amount of plant organic carbon was 13.60 ton C ha−1year−1 in 2012 and 14.29 ton C ha−1year−1 in 2013. And average organic carbon introduced to forest floor through litter production was 0.71 ton C ha−1year−1. Organic carbon distributed in forest floor litter layer was 0.73 ton C ha−1year−1 on average and accumulated organic carbon in soil was 51.13 ton C ha−1year−1 on average. In 2012, Amount of released CO2 from soil to atmosphere was 10.93 ton CO2 ha−1year−1. The net ecosystem production based on the difference between net primary production of organic carbon and soil respiration was −1.74 ton C ha−1yr−1 releasing more carbon than it absorbed.