• Journal of Korean Society for Geospatial Information Science
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• v.19 no.2
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• pp.39-48
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• 2011

Global warming causes the climate change and makes severe damage to ecosystem and civilization Carbon dioxide greatly contributes to global warming, thus many studies have been conducted to estimate the forest biomass carbon stock as an important carbon storage. However, more studies are required for the selection and use of technique and remotely sensed data suitable for the carbon stock estimation in Korea In this study, the aboveground forest biomass carbon stocks of Danyang-Gun in South Korea was estimated using $k$NN($k$-Nearest Neighbor) algorithm and regression model, then the results were compared. The Landsat TM and 5th NFI(National Forest Inventory) data were prepared, and ratio images, which are effective in topographic effect correction and distinction of forest biomass, were also used. Consequently, it was found that $k$NN algorithm was better than regression model to estimate the forest carbon stocks in Danyang-Gun, and there was no significant improvement in terms of accuracy for the use of ratio images.

• Korean Journal of Agricultural and Forest Meteorology
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• v.15 no.3
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• pp.119-129
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• 2013

This study was conducted to predict the changes in forest biomass in different ecoprovinces and forest types under climate change scenario based on cumulative data (i.e., digital forest site and climate maps, National Forest Inventory data) and various prediction models. The results from this study showed that predicted changes over time in biomass varied according to ecoprovince and forest type in Korea. A reduction in biomass was predicted for all forest types associated with the mountain, southeastern hilly, and southwestern hilly ecoprovinces. On the other hand, the biomass was predicted to increase for the coniferous forest and mixed-forest types in the central hilly ecoprovince. Furthermore, increases in biomass are predicted for all forest types, except coniferous forests, in the coastal ecoprovince. The results from this study provide a basis for developing technology to predict forest impacts due to climate change by predicting changes in forest biomass based on the estimation of site index.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.6
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• pp.538-544
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• 2014

A traditional fireplace has been used, but not much, for heating and cooking in rural area, Korea. Traditional fireplace as one type of biomass burnings is also emitting various air pollutants. Air pollutants emission from traditional fireplace was estimated in this study. There are two types of traditional fireplace, one for combined heating and cooking, the other one for cooking only. Types of fuels mostly used in traditional fireplace were wood, agricultural residue, solid waste. Activity levels such as fuel types, amount of fuel loading, and temporal variation were investigated by field survey over Korea. Estimated annual emissions from traditional fireplace were CO 6,335.0, NOx 555.0, SOx 9.6, VOC 1,771.7, TSP 181.4, $PM_{10}$ 119.9, $PM_{2.5}$ 96.2, $NH_3$ 1.4 ton/yr respectively. When emissions compared with the national emission inventory (CAPSS: Clean Air Policy Support System) of 2010 year, CO and $PM_{10}$ occupy 0.8% and 0.1% of total national emission, respectively.

• Journal of Korean Society for Atmospheric Environment
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• v.32 no.2
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• pp.167-175
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• 2016

In this study, we estimate air pollutants emission from agricultural waste burning. We investigated activities related to agricultural waste burning such as crop burning rates, location, and time by region. The average crop burning rates per square meter farmland of fruits, pulses, barleys, cereals, vegetables, and special crops were $273.1g/m^2$, $105.7g/m^2$, $7.4g/m^2$, $121.0g/m^2$, $290.7g/m^2$, and $392.9g/m^2$, respectively. We estimated air pollutants emissions with pre-developed emission factors. The estimated air pollutant emission of agricultural biomass burning were CO 148,028 ton/year, $NO_x$ 5,220 ton/year, $SO_x$ 11 ton/year, VOC 59,767 ton/year, TSP 21,548 ton/year, $PM_{10}$ 8,909 ton/year, $PM_{2.5}$ 7,405 ton/year, and $NH_3$ 5 ton/year. When these results compared with the entire emissions of national inventory (CAPSS), CO, VOC, $PM_{10}$ account for about 17.8%, 6.2%, 6.7% of the total, respectively.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.58 no.4
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• pp.352-358
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• 2022

We explored the frequency response of krill target strength (TS) to understand the Antarctic krill (Euphausia superba) and ice krill (Euphausia crystallorophias) using the stochastic distorted-wave Born approximation (SDWBA) model. The results showed that the distribution of orientation and the fatness factor could significantly impact on the frequency response of TS. Krill TS is clearly depended on acoustic properties, which could affect to estimate the biomass of two krill species. The results provide insight into the importance of understanding TS variation to estimate the Antarctic krill and ice krill biomass, and their ecology related to the environmental features in the Southern Ocean.

• Journal of agriculture & life science
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• v.53 no.2
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• pp.65-75
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• 2019

Stem and root of elm trees have used as traditional medical materials, but there is little information on the distribution and resources of habitats. Korean native growing Ulmus spp. (U. davidiana var. Japonica, U. parvifolia, U. davidiana, and U. macrocarpa) genetic resources studied through The National Forest Inventory of Korea data and field survey. The distributions of U. davidiana var. japonica according to elevation distributed evenly. Both U. parvifolia and U. davidiana were inhabited mostly at less than 200 m of altitude. Each Ulmaceae species widely were distributed nationwide, but a dominant species was different depending on locals. It observed that Ulmaceae inhabits mainly in steep slopes of 31-45 degrees. Most of the habitats regenerated by natural seeding and the most abundant species were a codominant tree. Distribution of trees in U davidiana var. japonica was 7 m-13 m, and in young U. parvifolia and U. macrocarpa, more than 25% of young trees less than 7 m observed. The distribution of the diameter of breast height of the U. davidiana var. japonica was 46.4% for 11-20 cm, 52.6% for 11-20 cm in U. parvifolia. The average T/R ratio was 0.83, and the mean weight ratio of root bark was 62%. As the results of this study, the domestic Ulmaceae biomassare very small. It is difficult to harvest in that the habitat on the slope. Thus, it is too hard to develop functional materials using biomass at present. Therefore, it is necessary to develop technology for the selection and propagation of elite trees of Ulmaceae.

• Journal of Korean Society of Forest Science
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• v.95 no.1
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• pp.50-54
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• 2006

Biomass expansion factors and stem density values were commonly used in converting stand volumes into total carbon stocks for the purpose of national inventories of greenhouse gas emissions and carbon sequestration. The objective of this study was to examine the influence of stand age classes on aboveground and total biomass expansion factors, and stem density values in Chamaecyparis obtusa species. A total of 25 representative sample trees based on the three different stand age classes were destructively sampled to measure green weights and dry weights of the major four(root, stem, branch and foliage) portions of C. obtusa species grown in Jangseung-gun of southern Korea. According to the results of this study, as stand age classes increase, total biomass expansion factors tended to be decreased with the ranges from 3.64 to 1.44, while the stem density values tended to be slightly increased with the ranges from $0.35(g/cm^3)$ to $0.44(g/cm^3)$. There were statistically significant differences in biomass expansion factors and stem density values between stand age classes, but became nearly constant after 30 years old for C. obtusa species. This information could be very useful to improve a national-scaled inventory of greenhouse gas emissions and carbon sequestration for the C. obtusa species by applying different biomass expansion factors and stem density values.

• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.3
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• pp.215-231
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• 2020

Forest landscape models (FLMs) can be used to investigate the complex interactions of various ecological processes and patterns, which makes them useful tools to evaluate how environmental and anthropogenic variables can influence forest ecosystems. However, due to the large spatio-temporal scales in FLMs studies, parameterization and validation can be extremely challenging when applying to new study areas. To address this issue, we focused on the parameterization and application of a spatially explicit forest landscape model, LANDIS-II, to Mt. Gyebang, South Korea, with the use of the National Forest Inventory (NFI) and long-term ecological research (LTER) site data. In this study, we present the followings for the biomass succession extension of LANDIS-II: 1) species-specific and spatial parameters estimation for the biomass succession extension of LANDIS-II, 2) calibration, and 3) application and validation for Mt. Gyebang. For the biomass succession extension, we selected 14 tree species, and parameterized ecoregion map, initial community map, species growth characteristics. We produced ecoregion map using elevation, aspect, and topographic wetness index based on digital elevation model. Initial community map was produced based on NFI and sub-alpine survey data. Tree species growth parameters, such as aboveground net primary production and maximum aboveground biomass, were estimated from PnET-II model based on species physiological factors and environmental variables. Literature data were used to estimate species physiological factors, such as FolN, SLWmax, HalfSat, growing temperature, and shade tolerance. For calibration and validation purposes, we compared species-specific aboveground biomass of model outputs and NFI and sub-alpine survey data and calculated coefficient of determination (R²) and root mean square error (RMSE). The final model performed very well, with 0. 98 R² and 8. 9 RMSE. This study can serve as a foundation for the use of FLMs to other applications such as comparing alternative forest management scenarios and natural disturbance effects.

• Journal of Korean Society for Atmospheric Environment
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• v.31 no.1
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• pp.83-91
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• 2015

Biomass burning is known to be one of the main sectors emitting greenhouse gases as well as air pollutants. Unfortunately, the inventory of biomass burning sector has not been established well. We estimated greenhouse gas (GHG) and air pollution (AP) integrated emissions from biomass burning sector in Seoul during year 2010. The data of GHG and AP emissions from biomass burning, classified into open burning, residential fireplace and wood stove, meat cooking, fires, and cremation, were obtained from Statistics Korea and Seoul City. Estimation methodologies and emission factors were gathered from reports and published literatures. Estimated GHG and AP integrated emissions during year 2010 were $3,867tonCO_{2eq}$, and 2,320 tonAP, respectively. Major sources of GHG were forest fires ($1,533tonCO_{2eq}$) and waste open burning ($1,466tonCO_{2eq}$), while those of AP were meat cooking (1,240 tonAP) and fire incidence (907 tonAP). Total emissions by administrative district in Seoul, representing similar patterns in both GHG and AP, indicated that Seocho-gu and Gangseo-gu were the largest emitters whereas Jung-gu was the smallest emitter, ranged in $2{\sim}165tonCO_{2eq}$ and 0.1~8.31 tonAP. GHG emissions per $km^2$ showed different results from total emissions in that Gwanak-gu, Jungnang-gu, Gangdong-gu and Seodaemun-gu were the largest emitters, while Seocho-gu and Gangseo-gu were near-averaged emission districts, ranged in $0.2{\sim}21tonCO_{2eq}/km^2$. However, AP emissions per $km^2$ revealed relatively minor differences among districts, ranged in $2.3{\sim}6.1tonAP/km^2$.

• Journal of Korean Society of Forest Science
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• v.94 no.6
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• pp.441-445
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• 2005

Researches on estimating national-scaled forest biomass are being carried out to quantify the carbon stock of forests with the Kyoto Protocol. In general, estimates of national-scaled forest biomass are based on forest inventory data which provides estimates of forest area, stem volume, and growth of stem by age classes. Estimates of forest biomass are, however, obtained by converting stem volumes to dry weight with stem density and thereafter to whole tree biomass with biomass expansion factors (ratios of whole tree dry weight to stem dry weight). Pinus densiflora is widely distributed and one of the most economically important timber species in Korea. The species are largely grouped into two ecotypes of Geumgang and Jungbu. Stems of Geumgang type trees are straight and high compared to those of Jungbu type trees. The objective of this study was to determine and compare stem density and biomass expansion factors fore two ecotypes of Pinus densiflora according to stand age. Stem density of both ecotypes of Pinus densora increased and biomass expansion factors of them decreased with increasing tree age. In he same age class, stem density and biomass expansion factor of Geungang type Pinus densiflora were lower than those of Jungbu type Pinus densiflora. There were statistically significant differences in stem density and biomass expansion factors between Geumgang type and Jungbu type Pinus densiflora in 0-20-year-old stands and 40-60-year-old stands. Our results suggested that the reliability of the national forest biomass inventory could be improved by applying the ecotype- and age-dependent stem density and biomass expansion factors.