• Korean Journal of Environmental Biology
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• v.30 no.2
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• pp.121-127
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• 2012

Cool-temperate broad-leaved deciduous forests are one of dominant forest cover types in Asia monsoon climate regions. However, our understanding of how much storages carbon in these ecosystems is limited. We studied carbon storage in three cool-temperate broad-leaved deciduous forests at Jirisan National Park, Korea. The biomass of trees in the three stands on an average was $112tC\;ha^{-1}$ and ranged from 107 to $119tC\;ha^{-1}$. The total amount of soil organic matter at a depth of 30 cm in the three stands on an average was $66tC\;ha^{-1}$. In addition, the total carbon stocks of biomass and soil was approximately $178tC\;ha^{-1}$, ranged from 167 to $184tC\;ha^{-1}$. Above values among three stands did not show the valuable difference at Jirisan National Park. The amounts of carbon storage in three ecosystems at Jirisan National Park, were higher than those of other studies significantly, except Seoraksan National Park.

• Journal of Korean Society of Forest Science
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• v.100 no.4
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• pp.708-714
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• 2011

Wood store carbon that the forest absorbed until burned or decomposed over a long period. Such materials are most used in houses except in paper and pulp, and the use of wood in houses play an important role in reducing green-house gases. Therefore, we estimated the amount of carbon stocks in Korean houses, and analyzed how much contribution such stocks offers to green-house gas reduction. As the result, the carbon stocks amount of the wood products in Korean houses was 28.4 million $tCO_2$, which is 4.6% of the total annual green-house gas emission in Korea (620 million $tCO_2$ e), and 77.4% of forest sinks (LULUCF). Even though few wooden houses which use most wood in housing exist in Korea, the carbon stocks of wood products in houses in 2010 increased to 4.1 times that in 1975 (21.4 million $tCO_2$) because the carbon stocks increased due to apartment construction, which hit its stride from the last 1980's.

• Proceedings of the Korean Society of Computer Information Conference
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• 2013.07a
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• pp.423-426
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• 2013

본 연구에서는 임분 단위에서 산림의 이산화탄소 흡수 및 저장 기능을 최적화 할 수 있는 최적의 산림시업체계를 도출하고자하였고, 이를 위해 임분 생장모델과 Simulated Annealing 휴리스틱 기법을 적용하여 임분탄소 최적화 프로그램을 개발하였다. 휴리스틱 알고리즘에서 최적해를 찾기 위해 반복 실행 되는 과정에서 더 이상 최적해을 찾지 못하고 목표 값이 어떤 일정한 값(Local Optimum)에 계속 머무는 현상을 해결하기 위해 임계치를 적용하며, SA 휴리스틱 기법에서는 열균형테스트를 이용하고 있다. 개발된 프로그램을 이용하여 3가지 산림 시업 시나리오에 대한 비교 분석을 실시하기 위해 프로그램을 실행한 결과, 목재수확량의 경우 목재수확량을 최대를 목표로 한 대안이 3개 시나리오 가운데 목재수확량이 가장 높은 것으로 나타났으며, 또한 탄소저장량에서도 탄소저장량을 최적화한 대안이가 탄소저장량이 가장 높은 것으로 나타나 프로그램이 목적에 맞게 개발된 것으로 판단됐다. 또한 열균형 테스트의 온도저감율을 조정하여 프로그램을 반복실행하여 온도저감율이 프로그램 실행 시에 미치는 영향을 분석한 결과 온도저감율에 따라 출력되는 목적함수의 최적값과 프로그램 반복횟수가 영향을 받는 것으로 나타나 프로그램 실행을 최적으로 하기위해 온도 저감율의 파라미터 값을 0.1로 설정하였다.

• Journal of Environmental Impact Assessment
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• v.32 no.6
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• pp.377-388
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• 2023

Carbon management is emerging as an important factor for global warming control, and land use change is considered one of the causes. To quantify the changes in carbon stocks due to development, this study attempted to calculate carbon storage by borrowing the formula of the InVEST Carbon Storage and Sequestration Model (InVEST Model). Before analyzing carbon stocks, a carbon pool was compiled based on previous studies in Korea. Then, we estimated the change in carbon stocks according to the development of Osong National Industrial Park (ONIP) and the application of alternatives. The analysis shows that 16,789.5 MgC will be emitted under Alternative 1 and 16,305.3 MgC under Alternative 2. These emissions account for 44.4% and 43.1% of the pre-project carbon stock, respectively, and shows that choosing Alternative 2 is advantageous for reducing carbon emissions. The difference is likely due to the difference in grassland area between Alternatives 1 and 2. Even if Alternative 2 is selected, efforts are needed to increase the carbon storage effect by managing the appropriate level of green cover in the grassland, creating multi-layered vegetation, and installing low-energy facilities. In addition, it is suggested to conserve wetlands that can be lost during the stream improvement process or to create artificial wetlands to increase carbon storage. The assessment of carbon storage using carbon pools by land cover can improve the objectivity of comparison and evaluation analysis results for land use plans in Environmental Impact Assessment and Strategic Environmental Impact Assessment. In addition, the carbon pool generated in this study is expected to be used as a basis for improving the accuracy of such analyses.

• Journal of Energy Engineering
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• v.18 no.2
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• pp.141-146
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• 2009

In present work, we study the hydrogen storage of MWNT decorated with bimetallic Pt and Pd nanosize catalysts by Thermal Vapor Deposition [TVD]. The size of Pt and Pd particles is controlled as 5nm, 3nm, respectively by TVD. Before hydrogen storage measurement, the sample was heated for 1hr at $200^{\circ}C$ in H2 atmosphere. The Hydrogen sto rage of the sample was performed at room temperature and 33~34atm. The hydrogen storage of this composite showed 3.2wt% at 298K and 34atm, for three times. At 4th cycle, hydrogen storage is decreased to 1.5wt%, owing to the aggregation of bimetallic Pt and Pd nano particles.

• Journal of the Korean Association of Geographic Information Studies
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• v.18 no.4
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• pp.81-99
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• 2015

The acceleration of global warming has required better understanding of carbon cycles over local and regional areas such as the Korean peninsula. Since forests serve as a carbon sink, which stores a large amount of terrestrial carbon, there has been a demand to accurately estimate such forest carbon sequestration. In Korea, the National Forest Inventory(NFI) has been used to estimate the forest carbon stocks based on the amount of growing stocks per hectare measured at sampled location. However, as such data are based on point(i.e., plot) measurements, it is difficult to identify spatial distribution of forest carbon stocks. This study focuses on urban areas, which have limited number of NFI samples and have shown rapid land cover change, to estimate grid-based forest carbon stocks based on UNFCCC Approach 3 and Tier 3. Land cover change and forest carbon stocks were estimated using Landsat 5 TM data acquired in 1991, 1992, 2010, and 2011, high resolution airborne images, and the 3rd, 5th~6th NFI data. Machine learning techniques(i.e., random forest and support vector machines/regression) were used for land cover change classification and forest carbon stock estimation. Forest carbon stocks were estimated using reflectance, band ratios, vegetation indices, and topographical indices. Results showed that 33.23tonC/ha of carbon was sequestrated on the unchanged forest areas between 1991 and 2010, while 36.83 tonC/ha of carbon was sequestrated on the areas changed from other land-use types to forests. A total of 7.35 tonC/ha of carbon was released on the areas changed from forests to other land-use types. This study was a good chance to understand the quantitative forest carbon stock change according to the land cover change. Moreover the result of this study can contribute to the effective forest management.

• Journal of the Korean Association of Geographic Information Studies
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• v.17 no.4
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• pp.69-85
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• 2014

Carbon stocks of NFI plots can be accurately estimated using field survey information. However, an accurate estimation of carbon stocks in other unsurveyed sites is very difficult. In order to fill this gap, various spatial information can be used as an ancillary data. In South Korea, there is the 1:5,000 forest type map that was produced by digital air-photo interpretation and field survey. Because this map contains very detailed forest information, it can be used as the high-quality spatial data for estimating carbon stocks. In this study, we compared three upscaling methods based on the 1:5,000 forest type map and 5th national forest inventory data. Map algebra(method 1), RK(Regression Kriging)(method 2), and GWR(Geographically Weighted Regression)(method 3) were applied to estimate forest carbon stock in Chungcheong-nam Do and Daejeon metropolitan city. The range of carbon stocks from method 2(1.39~138.80 tonC/ha) and method 3(1.28~149.98 tonC/ha) were more similar to that of previous method(1.56~156.40 tonC/ha) than that of method 1(0.00~93.37 tonC/ha). This result shows that RK and GWR considering spatial autocorrelation can show spatial heterogeneity of carbon stocks. We carried out paired t-test for carbon stock data using 186 sample points to assess estimation accuracy. As a result, the average carbon stocks of method 2 and field survey method were not significantly different at p=0.05 using paired t-test. And the result of method 2 showed the lowest RMSE. Therefore regression kriging method is useful to consider spatial variations of carbon stocks distribution in rugged terrain and complex forest stand.

• Journal of agriculture & life science
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• v.46 no.1
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• pp.43-51
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• 2012

This study was conducted to develop growth model and to estimate carbon storage of Quercus variablis stands. The study sites were located in the Yangpyeong and Gangneung regions. A total of 30 sample trees were harvested for data collection. According to the results of the application of Chapman-Richards model in this study, the coefficient of determination($R^2$) for the DBH-height model in Yangpyeong region was 97% while 94% in Gangneung regions. For the age-height relationship, the $R^2$ in Yangpyeong regions was 99% while 94% in Gangneung regions. The total carbon stored in Yangpyeong region was $83.0Mg\;C\;ha^{-1}$ while $137.3Mg\;C\;ha^{-1}$ in Gangneung.

• Journal of Korean Society of Forest Science
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• v.110 no.2
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• pp.233-243
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• 2021

Considering worldwide efforts to mitigate repercussions of climate change, the South Korean government has declared to reach net zero by 2050 to achieve a carbon-neutral sustainable society. For full implementation of NDCs, the government has actively reflected its forestry sector into these strategies. Since coarse woody debris (CWD) in forests represents an enduring carbon storage, it is of particular significance to determine characteristics of changes in carbon stocks of CWD by utilizing data on dead trees monitored in permanent sample plots within national forest inventories (NFIs). In this study, therefore, both occurrence and carbon stocks of CWD were estimated in such plots using data on CWD from the 5^th, 6^th, and 7^th NFIs. Subsequently, characteristics of changes in carbon stocks over time were analyzed. Based on the analysis of 2,021 plots available for monitoring in each NFI of Gangwon Province, the volume of CWD (m³ ha^-1) was found to be 4.71 in the 5^th NFI and 4.09 in the 6^th NFI. However, the volume of CWD declined to 3.09 in the 7^th NFI. Moreover, the annual carbon stocks of CWD (ton C ha^-1) were estimated to be 0.67 in 2009, 0.64 in 2014, and 0.41 in 2019, showing a downward trend over time. This study provides a basis for future research to investigate long-term changes and estimate carbon stocks of CWD in South Korea forests.

• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.733-743
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• 2020

We estimated the carbon storage of coal mines reclaimed using Betula platyphylla (BP), Pinus koraiensis (PK), and Pinus spp. (PS, Pinus densiflora, Pinus rigida, and Pinus thunbergii). The carbon storage of tree biomass (TB), forest floor(FF), mineral soil (MS), and the total forest were quantified. Reclaimed sites were located in Gangwon-do, Gyeongsangbuk-do, and Jeollanam-do; reclamation was conducted at various times in each region. The carbon storage (ton C ha^-1) in FF (BP: 3.31±0.59, PK: 3.60±0.93, PS: 4.65±0.92), MS (BP: 28.62±2.86, PK: 22.26±5.72, PS: 19.95±3.90), and the total forest(BP: 54.81±7.22, PK: 47.29±8.97, PS: 45.50±6.31) were lower than that of natural forests (NF). The carbon storage in TB was lower in BP (22.57±6.18) compared to NF, while those in PK(21.17±8.76) and PS (20.80±6.40) were higher than in NF. While there were no significant differences in the carbon storage of TB, FF, and the total forest among tree species, results from MS showed a significant difference among species. TB and the total forest carbon storages in all sites increased after reclamation. Soil pH and cation exchange capacity values in BP and PS were lower than in NF. Amounts of labile carbon, available phosphate, and microbial biomass carbon in reclaimed sites were less than half of NF. There are a number of methods that could increase the reclamation efficiency. Applications of lime or organic fertilizers, as well as tillage operations, may improve soil properties in reclaimed coal mines. Additionally, pruning and thinning would increase tree growth thereby increasing carbon storage.