Seasonal Variation of Soil Respiration in the Mongolian Oak (Quercus mongolica Fisch. Ex Ledeb.) Forests at the Cool Temperate Zone in Korea

Osmundastrum cinnamomeum population differences in three habitat types in South Korea

Most ferns occur in moist and shaded environments; their relatively narrow band of survival conditions increase their extinction risk under Anthropocene-linked climate change. Osmundastrum cinnamomeum (L.) C. Presl is a perennial fern that has a natural distribution primarily encompassing the East Asian mountains. In this study, we characterized the vegetation and environmental factors in low- and high-elevation mountain ranges and montane wetlands to elucidate the optimal habitat for O. cinnamomeum. We found that populations of O. cinnamomeum developed better in high-elevation mountains than in low-elevation mountains. However, the low light intensity in high mountain forests reduces opportunities for reproduction. The montane wetlands recorded the highest biomass among the three habitat types, and the investment in reproduction was also significantly higher. The montane wetlands also showed higher light intensity, substrate fertility, and water content. Overall, the montane wetlands were found to be the optimal habitat for O. cinnamomeum. At lower elevations, lower precipitation, higher temperatures, human disturbance, and low substrate water could be factors limiting the expansion of this fern's distribution. Our study points to the importance of conserving montane wetlands to prevent the extinction of ferns.

Assessment of the Carbon Budget of Local Governments in South Korea

This study was carried out to assess the carbon budget of local governments in South Korea. The carbon budget was obtained from the difference between net ecosystem productivity (NEP) that the natural ecosystem displays, and carbon dioxide emissions calculated from energy consumption in each local government. NEP was obtained from the difference between net primary productivity, measured by an allometric method, and soil respiration, measured with EGM-4 in natural forests and artificial plantations. Heterotrophic respiration was adjusted to 55% level of the total soil respiration based on existing research results. A field survey to obtain information for components of the carbon cycle was conducted in Cheongju (central Korea) and Yeosu (southern Korea). Pinus densiflora, Quercus acutissima, and Quercus mongolica (central Korea) and P. densiflora and Q. acutissima (southern Korea) forests were selected as the natural forests. Pinus rigida and Larix kaempferi (central Korea) and P. rigida (southern Korea) plantations were selected as the artificial plantations. Vegetation types were classified by analyzing LandSat images by applying a GIS program. CO2 emissions were the highest in Pohang, Gwangyang, and Yeosu, where the iron and the petrochemical industrial complexes are located. CO2 emissions per unit area were the highest in Seoul, followed by Pohang and Gwangyang. CO2 absorption was the highest in the Gangwon province, where the forest area ratio to the total area is the highest, and the lowest in the metropolitan areas such as Seoul, Incheon, Daegu, Daejeon, and Gwangju. The number of local governments in which the amount of absorption is more than the emission amount was highest in Gangwon-do, where 10 local governments showed a negative carbon budget. Eight, seven, five, five, three, and three local governments in Gyeongsangbuk-do, Jeollanam-do, Gyeongsangnam-do, Jeollabuk-do, Gyeonggi-do, and Chungcheongbuk-do, respectively, showed a negative carbon budget where the amount of carbon absorption was greater than the emission amount. The carbon budget showed a very close correlation with carbon emission, and the carbon emission showed a significant correlation with population size. Moreover, the amount of carbon absorption showed a negative correlation with population size, population density, and non-forest area, and a positive correlation with the total area of the forest, coniferous forest area, and broad-leaved forest area. Considering the reality that carbon emissions exceed their absorption, measures to secure absorption sources should be considered as important as measures to reduce carbon emissions to achieve carbon neutrality in the future. As a measure to secure absorption sources, it is proposed to improve the quality of existing absorption sources, secure new absorption sources such as riparian forests, and efficiently arrange absorption sources.