• The Korean Journal of Ecology
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• v.24 no.1
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• pp.51-59
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• 2001

Estimation of the annual net production, nitrogen (N) and base cation (BC＝K, Mg, Ca) uptake by stocked forests in South Korea has been done with national statistical data of forestry from 1995 to 1999. The annual net production of stems and branches was about 1.8 ton DM ha/sup -1/ yr/sup -1/. The net productivity of deciduous forests was higher than that of coniferous forests. Total net production of the stocked forests from the whole stocked area of South Korea of 6.246×10/sup 6/ ha, was about 1.13×10/sup 7 ton DM/yr, and the total harvested biomass obtained from timber production data in 1999, was estimated about 6.1×105 ton DM/yr that was equivalent to 98 kg DM ha/sup -1/ yr/sup -1/f. Net growth uptake of N and BC were 350 mol ha/sup -1/ yr/sup -1/ and 296 mol ha/sup -1/ yr/sup -1/ respectively, and the content of N and BC contained in the harvested biomass were 20 mol ha/sup -1/ yr/sup -1/ and 16 mol ha/sup -1/ yr/sup -1/ respectively. Net uptake of N was higher than that of BC. Total net uptake of N and BC from growth and harvest by stocked forests in South Korea were 2.309×10/sup 9/ mol/yr and 1.953×10/sup 9 mol/yr respectively.

• Journal of Korean Society of Forest Science
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• v.107 no.2
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• pp.113-125
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• 2018

Subalpine zone is geographically vulnerable to climate change. Forest vegetation in this zone is one of the important basic indicator to observe the influence of climate change. This study was conducting phytosociological community classification and endemic-rare plants investigation based on vulnerable species to climate change at the subalpine zone, Mt. Jiri. Vegetation data were collected by 37 quadrate plots from March to October, 2015. In order to understand the species composition of plant sociological vegetation types and the ecological impacts of species, we analyzed the layer structure of vegetation type using important values. Vegetation type was classified into eight species groups and five vegetation units. The vegetation types can be suggested as an indicator on the change of species composition according to the future climate change. There were 9 taxa endemic plants and 17 taxa rare plants designated by KFS(Korea Forest Service) where 41.2% of them were the northern plant. Endemic-rare plants increased as the altitude of vegetation unit increase. Importance value analysis showed that the mean importance value of Abies koreana was highest of all vegetation units. Based on analysis of each layer, all units except vegetation unit 1 were considered to be in competition with the species such as Quercus mongolica and Acer pseudosieboldianum. The results of this study can be a basic data to understand the new patterns caused by climate change. In addition, it can be a basic indicator of long-term monitoring through vegetation science approach.

• Journal of Korean Society of Forest Science
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• v.109 no.1
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• pp.81-98
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• 2020

In this study, forest-related research papers published in North Korean journals were analyzed to understand the research trends in North Korean forest science. The Korea Science and Technology Information Institute (KISTI) North Korea Science and Technology Network (NKtech) is constructing a database related to science and technology in North Korea. From this, a total of 1,389 articles published from 1962 to 2016 were collected with forest science key words based on the South Korean National Science and Technology Standard Classification System. The topics were divided into four categories: afforestation, forest protection, forest use, and forest management. In the field of afforestation, research activities on nursery and agroforestry were active, and the survival rate was emphasized. In the forest protection field, there was a significant research effort into forest pests, and efforts were being made to reduce soil erosion through agroforestry. In the field of forest use, research activities on pulp/paper and mushrooms were active. In the forest management field, activities related to "ecological information" were conspicuous, and efforts were being made to reduce carbon. These results suggest that the perspective of North Korean forest research has changed from nature reorganization to nature protection. Thus, a comparative study on forest science and technology in each sub-sector of the forest research field, along with analysis of the relationship between policy direction and research direction of North Korea over time, would be worthwhile future investigations. To overcome the problem of technical terminology, a compilation/dictionary of inter-Korean forestry terminology would be useful for effective communication between the two Koreas.

• Journal of Society of Preventive Korean Medicine
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• v.7 no.1
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• pp.1-15
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• 2003

This study tried to evaluate the difference of stress degree by Sasang constitution and lifestyle for workplace labors, and suggested the preventive oriental medicine approaches in occupational health area. 479 data for research were collected through the process of oriental health examination with questionnaire in workplace, and collected data were analyzed with frequency, crosstab, and Two-Way ANOVA. The results were as follows: 1) All subjects, total 479 were men, and constitutional distributions were 39.2% of Taeumin, 32.4% of Soumin, and 28.4% of Soyangin. The distributions of stress score were 13.2% of normal group, 13.4% of high risk group, and 73.5% of potential risk group. 2) There were no statistically significant differences for stress by constitution(p=0.085). By the results of optimal scaling and homogeneity analysis, Soyangin was close to potential risk group compared to other constitution, and Soumin and Taeumin were close to high risk and normal group, respectively. 3) For the difference of stress score by Sasang constitution and lifestyle, Soumin who exercised nearly everyday had the highest stress score with interaction in Factor 4 area(p<0.05), and there was no interaction in other area. 4) For the difference of PWI score by lifestyle, there were statistically significant differences for drinking(p<0.01), smoking(p<0.01), and obesity index(p<0.01)

• Korean Journal of Environmental Biology
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• v.37 no.2
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• pp.204-216
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• 2019

To evaluate the biological integrity of aquatic ecosystems, we developed Korean multimetric diatom index (KMDI) using metrics that many researchers have been previously described, and compared to single-metric diatom index such as trophic diatom index (TDI) and diatom assemblage index to organic pollution (DAIpo). For the biological and environmental data, we investigated the epilithic diatoms, water quality and the land-use for 923 sites in Korean streams between 2013-2017, and estuaries between 2010-2017, respectively. Five appropriate metrics were selected according to the following steps; 1) extraction of 300 potential metrics (biological, chemical, physical, and geographical) based on previous references, of these, 2) 46 samples having high separation power were selected, 3) the selected metrics were each tested for variability, redundancy, and sensitivity to the environments, finally 4) construction of multi-metric diatom index comprising single type metrics such as TDI, DAIpo, % motile diatoms, % Achnanthes / (Achnanthes+Navicula), and % number of Gomphonema species. The biological integrity of the 233 sites from the Geum River basin were independently investigated using KMDI. Collectively, the new KMDI showed high sensitivity and explanatory power for environmental factors such as land-use, biochemical oxygen demand, total nitrogen, and electric conductivity. However, it had slightly higher biological integrity for the same sites as compared to single type diatom metrics. Finally, more data accumulation from all over Korea and the development of acceptable diatom metrics were required.

• Korean Journal of Environmental Biology
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• v.38 no.1
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• pp.71-81
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• 2020

In Korea, more than 70% of the ammonia(NH₃) released into the atmosphere is known to originate from livestock manure. The total emission (kg year^-1) is calculated by multiplying the emission factor (kg head^-1 yr^-1) and the activity data (head). To improve the accuracy and reliability of the NH₃ emission estimation process, an accurate account of livestock manure production, calculation of NH₃ conversion and generation during the composting and liquefaction of manure, estimation of NH₃ generation in the storage and transportation of manure and compost, and a comparative study of NH₃ emission during the soil spreading process must be performed. Compared to the US and EU-28, in particular, the domestic emission factor is relatively even and the spatial/temporal scale is not broken down sufficiently to reflect the domestic situation. As a way to improve the accuracy and expertise of estimating NH₃ emission factors, a 'dynamic chamber-capture system' can be utilized, which allows complex considerations of compost, liquid manure, soil, and climate characteristics. By reviewing and comparing the data related to domestic and foreign NH₃ emission, we identified shortcomings in the current domestic system and the directions to be taken and suggested a chamber system that could estimate NH₃ emission flux. It is also necessary to establish a methodology for mesocosm systems in the field, in addition to indoor chamber systems, to be linked with practical policies, such as the calculation of new emission factors for missing sources.

• Korean Journal of Ecology and Environment
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• v.42 no.3
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• pp.271-279
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• 2009

Vinyl chloride (VC) is a known human carcinogen, and it is released to multi-environmental media via several exposure routes. VC was potentially evaluated as a water quality pollutant based on human health risk assessment in Korean water environments. In this study, we investigated physicochemical and toxicological properties of VC, human health and ecological risk assessment, and the regulation of VC as a water quality pollutant in developed countries. Currently there are no standard or guideline values of VC in Korean legal system for the protection of human health and aquatic ecosystem, except that it is designated as a specific toxic substance and a water quality pollutant. Human health risk assessment of VC was previously performed based on the limited water quality monitoring data. The monitoring level of VC in Korean water system is more higher than other countries'. VC was assessed as potential hazardous chemical based on the US EPA's cancer risk assessment. There were a few ecotoxicity data of VC available using very limited kinds of aquatic organisms, and the toxicity results obtained seem to be overestimated without considering the losses of VC in open exposure system. Therefore it is needed to monitor the VC in various areas and to carry out the ecotoxicity research using multi-level organisms. We expect that these results can be useful information for implementing VC as a water quality pollutant in legal system for the protection of human health and aquatic ecosystem in near future.

• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.3
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• pp.199-207
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• 2006

Recent global warming seems to be dramatic and has influenced forest ecosystems. Changes in phonology of biota, species distribution range shift and catastrophic climatic disasters due to recent global warming have been observed during the last century. Korean forests located mainly in the temperate zone also have been experienced climatic change impacts including shifting of leafing and flowering phonology, changes in natural disasters and forest productivity, However, little research has been conducted on the impact of climate change on forest ecosystems in Korea which is essential to assess the impact and extent of adaptation. Also there is a shortage in basic long-term data of forest ecosystem processes. Careful data collection and ecological process modeling should be focused on characteristic Korean forest ecosystems which are largely complex terrain that might have hindered research activities. An integrative ecosystem study which covers forest dynamics, biological diversity, water and carbon flux and cycles in a forest ecosystem and spatial and temporal dynamics modeling is introduced. Global warming effects on Korean forest ecosystems are reviewed. Forestry activity and the importance of forest ecosystems as a dynamic carbon reservoir are discussed. Forest management options and challenges for future research, impact assessment, and preparation of mitigating measures in Korea are proposed.

• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.4
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• pp.215-219
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• 2001

Land surface parameterization schemes for atmospheric models as well as decision support tools for ecosystem management require a frequent updating of land cover classification data for regional to global scales. Rice paddies have not been treated independently from other agricultural land classes in many classification systems, despite their atmospheric and ecological significance. A simple but improved method over conventional land cover classification schemes for rice paddy is suggested. Normalized difference vegetation index (NDVI) was calculated for the land area of South Korea at a 1km by 1 km resolution from the visible and the near-infrared channel reflectances of NOAA-AVHRR (Advanced Very High Resolution Radiometer). Monthly composite images of daily maximum NDVI were prepared for May and August, and used to classify 4 major land cover classes : urban, farmland, forests and water body. Among the pixels classified as "forests" in August, those classified as "water body" in May were assigned a "rice paddy" class. The distribution pattern of "rice paddy" pixels was very similar to the reported rice acreage of 1,455 Myons, which is the smallest administrative land unit in Korea. The correlation coefficient between the estimated and the reported acreage of Myons was 0.7, while 0.5 was calculated from the USGS classification.calculated from the USGS classification.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.759-768
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• 2019

This study was conducted to estimate the mean annual extreme minimum temperature raster and predict the potential distribution of the invasive plant, Ipomoea triloba, on the Korean peninsula. We collected annual extreme minimum temperature and mean coldest month minimum temperature data from 129 weather stations on the Korean peninsula from 1990-2019 and used this data to create a linear regression model. The min temperature of the coldest month raster from Worldclim V2 were used to estimate a 30 second spatial resolution, mean annual extreme minimum temperature raster of the Korean peninsula using a regression model. We created three climatic rasters of the Korean peninsula for use with the Proto3 species distribution model and input the estimated mean annual extreme minimum temperature raster, a Köppen-Geiger climate class raster from Beck et al. (2018), and we also used the mean annual precipitation from Worldclim V2. The potential distribution of I. triloba was estimated using the Proto3 model with 117 occurrence points. As a result, the estimated area for a potential distribution of I. triloba was found to be 50.7% (111,969 ㎢) of the Korean peninsula.