• Korean Journal of Soil Science and Fertilizer
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• v.34 no.5
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• pp.358-364
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• 2001

To obtain information for the proper fertilization management of cut-flower roses, the amount of macro and micro elements absorbed by cut-flower roses from soil for a year was investigated. Three cut-flower rose cultivars which are called 'Grandgara', 'Nobless', and 'Centina' were transplanted to a sandy loam soil, N-P-K standard fertilization was applied to the soil, and drip irrigation was done at the level of 10 kPa soil moisture tension. There was not significantly different in the harvest amount of cut-flower rose between 'Grandgara' and 'Nobless', but the harvest yield of 'Centina' was about 63% level when compared to that of 'Grandgara'. Considering seasonal changes in the content of nutrients in plant, parts, the uptake of untrients was higher in winter season than that in spring and summer seasons. Except for 'Centina', the nutrient amount removed from plant parts of 'Grandgara' and 'Nobless' increased with the sequence of floral part < stem < leaf, indicating that it is more dependent on biomass yield than on the content of nutrients in each plant part. The ratio of N/K amount absorbed by 'Nobless' and 'Centina' was 1.13 and 1.28. respectively, lower than 1.68 of 'Grandgara', showing that the requirement for K is greater in 'Nobless' and 'Centina' than in 'Grandgara'. The use efficiency of nutrients by cut-flower roses ranged from 39 to 64% in nitrogen, 5 to 9% in phosphorus, and 37 to 67% in potassium. It suggests that the requirement for P in cut-flower roses is very low.

• Korean Journal of Environment and Ecology
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• v.24 no.5
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• pp.591-600
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• 2010

We estimated and compared C storages and annual $CO_2$ uptakes by 9 dominant tree species planted along the streets. DBH and age by tree species were measured in the sites selected considering the planting status and distributions of tree species, and biomass, C storage, growth rate, and annual $CO_2$ uptake were estimated for each species. As a result, L. tulipifera, M. glyptostroboides, P. occidentalis were classified into fast-growing group, P. serrulata, G. biloba, Z. serrata, S. japonica, A. palmatum showed intermediate growth rates, and P. densiflora was slow-growing. Average C storage per tree was 205kgC/tree and ranged from 518kgC/tree(L. tulipifera) to 41kgC/tree(P. densiflora). Average annual $CO_2$ uptake by urban street trees over their lifespan ranged from $7.6kgCO_2$/tree/y to $99.1kgCO_2$/tree/y and L. tulipifera was the greatest, followed by glyptostroboides and P. occidentalis, and P. densiflora was the lowest. Total annual $CO_2$ uptake by all street trees in Gyeonggi-do, estimated based on the annual $CO_2$ uptake by each species, was as small as approximately 0.67% of that by forest in Gyeonggi-do. However, urban trees are still important because forest area continues to decrease and urbanization occurs annually in Gyeonggi-do, and should be managed considering their multi-functional aspects, including mitigation of heat island effect and building energy saving(indirect $CO_2$ uptake).

• Journal of Korean Society of Forest Science
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• v.98 no.3
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• pp.324-330
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• 2009

The objective of this study is to estimate the carbon sequestration in forest stands using KOMPSAT-2 imagery. For estimating the amount of carbon sequestration, the stand biomass of forest was estimated with the total weight, which was the sum of individual tree weight. Individual tree volumes could be estimated by the crown width extracted from KOMPSAT-2 imagery. In particular, the carbon conversion index and the ratio of the $CO_2$ molecular weight to the C atomic weight, reported in the Intergovernmental Panel on Climate Change (IPCC) guideline, was used to convert the stand biomass into the amount of carbon sequestration. Thereafter, the KOMPSAT-2 imagery was classified with the segment based classification (SBC) method in order to quantify carbon sequestration by tree species. This approach, estimating the amount of carbon sequestration for certain species in stand, can be available to extend plot-based carbon sequestration to stand-based carbon sequestration.

• The Korean Journal of Pesticide Science
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• v.3 no.2
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• pp.81-85
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• 1999

Concentration change of soil-applied pretilachlor (2-chloro-2',6'-diethyl- N-2-propoxyethyl)-actanilide) was investigated under upland condition with various soil moisture contents ranging from 50 to 80%(water content by weight). Following pretilachlor from each soil solution was extracted by centrifugation using double tubes, its concentration was determined by HPLC. Pretilachlor concentration in the soil solutions were almost the same under various soil moisture conditions. However, the total amount of pretilachlor increased as the soil moisture content increased. With increasing soil moisture content, the bioactivity of soil-applied pretilachlor on inhibiting the growth of Echinochloa ultilis Ohwi et Yabuno and the absorption of $^{14}C$-pretilachlor in its plants were also enhanced. Our results demonstrate that the absorption of pretilachlor in plants varies with soil moisture content and thus the bioactivity of soil-applied pretilachlor on inhibiting plant growth is different under various soil moisture conditions at the same dosage based on air-dried weight.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.29 no.1
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• pp.55-62
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• 2011

Amidst the raising of climate change in relation to the earth's environment as an international issue, there is a growing interest in forest resources. In particular, Korea faces a period in which we need to control carbon release pursuant to the Convention on Climate Change and the enforcement of the Kyoto Protocol; therefore, the importance of forests is becoming greater. Recently, there has been a focus on light detection and ranging (Lidar) which is a means of acquiring in a short time various necessary pieces of information for forest management as three dimensional geospatial information. In this study, the carbon absorption of a forest was measured by using the Lidar data obtained from the Lidar. Carbon absorption release was calculated on the basis of three criteria involving the minimum height of a tree, the density of the forest, and the minimum area of the forest, which are items proposed by the Forest resources surveyor. Through this study, a method of extracting the carbon absorption of a forest area using the Lidar data quantitatively was confirmed.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2001.04b
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• pp.77-78
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• 2001

순환식 양액재배에서 근권부 배지의 종류가 작물의 양분흡수에 미치는 영향을 구명하고자 하였다. 배지별 양액흡수량은 토마토 및 오이 모두 같은 경향이었는데, 단위일사량당 양액흡수량을 보면 오이는 생육 전반기인 6월 5일까지 지속적으로 양액흡수가 이루어지다가 일사량에 따라 전체 양액의 흡수가 변화하였다. 그러나 단위일사량당 양액흡수량은 생육 후반기에 일정한 수준을 유지하였는데 이것은 노화된 하엽을 제거하였기 때문으로 보인다(Fig 1). 배지에 따른 양액흡수량은 전체적으로 암면에서 생육 후기까지 다소 높은 경향을 보였으나 통계적으로 유의성은 인정되지 않았다. 또한 배지간의 무기이온 흡수율은 이온별로 차이가 있었으나 모든 이온에서 유의성은 인정되지 않았다. 배지에 따른 무기이온 흡수량은 전체적으로 암면에서 생육 후기까지 다소 높은 경향을 보였으나 통계적으로 유의성은 인정되지 않았다(Fig. 2). 작물의 생육 및 수량에서도 암면에서 전반적으로 높은 경향을 보였으나 통계적으로 유의성을 보이지는 않았으나 오이의 엽중은 암면에서 무거웠고 엽건물중도 차이가 있었다. 기타 생육 요소간에는 유의성이 인정되지 않았지만 암면에서 다소 좋은 경향을 보였다(Table 1). 따라서 작물의 무기이온 흡수량을 추정하는 모델식의 입력요소로 배지 종류는 적합하지 않았으며 다만 수분 보유력이 좋은 암면에서 양액 흡수량이 많았다는 결과를 얻었다.

• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.554-568
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• 2021

Forests are the largest carbon (C) sinks in terrestrial ecosystems. Recently, as enhancing forest C sequestration capacity has been proposed as a basic direction of the Republic of Korea's "2050 Carbon Neutral Strategy," accurate estimation of forest C sequestration has been emphasized. According to the Intergovernmental Panel on Climate Change guidelines, sequestration quantity is calculated from changes in C stocks in forest C pools, such as biomass, deadwood, litter and soil layer, and harvested wood products. However, in Korea, only the overstory biomass increase is now considered the amount of sequestration quantity, so there can be a significant difference from the actual forest C sequestration. In this study, we quantified forest C exchange through C flux measurement using an eddy covariance system and an automated soil chamber system in a 57-year-old Korean pine plantation located in Mt. Taehwa, Gwangju-si, Gyeonggi-do. Then, the net amount of C sequestration was compared with the amount of the overstory biomass increase. We estimated the annual C stock change in the remaining C pools by comparing the net sequestration amount from the C flux measurement with the overstory biomass increase and C stock change in the litter layer. Therefore, the net C sequestration of the Korean pine plantation estimated from the flux measurement was 5.96 MgC ha^-1, which was about 2.2 times greater than 2.77 MgC ha^-1 of the overstory biomass increase. The annual C stock increase in the litter layer was estimated to be 0.75 MgC ha^-1, resulting in a total annual C stock increase of 2.45 MgC ha^-1 in the remaining C pools. Our results indicate that the domestic forest is a larger C sink than the current methods, implying that more accurate calculations of the C sequestration capacity are necessary to quantify C stock changes in C pools along with the C flux measurement.

• 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 Bio-Environment Control
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• v.10 no.3
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• pp.133-140
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• 2001

This study was conducted to develop a nutrient uptake model in cucumnber (Cucumis sativus L. cv. Eunsung Backdadagi) plants for prediction of the amount of nutrients in drainage solution in a closed perlite culture system. Electrical conductivity (EC) of the nutrient solution was adjusted to 1.5, 1.8, 2.1, 2.4, and 2.7 dS. $m^{-1}$ . The amount of nutrient solution absorbed in different EC treatments was not different until the mid stage of growth. However, after the mid growth stage, a high EC treatment resulted in less solution absorption. The absorption rates of K, N $O_3$$^{[-10]}$ -N, Mg, and P increased continuously for a whole growing period in all treatments, while those of Ca decreased slightly. For S, the decrease was significant after th mid stage of growth. although the amounts of absorbed inorganic ions in different EC treatments were not significantly different at the first stage of growth, they were significantly different after the mid stage of growth and decreased slightly at the end of growth stage. Models for predicting the amounts of each inorganic ion absorbed were developed by using EC and the amount of nutrient solution absorbed per unit radiation(mg.M $J^{-1}$), which proved to be practical with a positive correlation at 1 percent probability between the developed model and practical values..

• Korean Journal of Weed Science
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• v.15 no.4
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• pp.321-328
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• 1995

Absorption, translocation, and metabolism study of $^{14}C$-bensulfuron were conducted to determine selectivity and herbicidal action of bensulfuron in two rice cultivars and three paddy weeds at different temperatures. 1. Absorption of $^{14}C$-bensulfuron was greater at 30/$25^{\circ}C$ than at 25/$20^{\circ}C$ and also in cv. Sangpung than in cv. Samgang, and Cyperus serotinus and Sagittaria pygmaea showed greater amount of absorption than Echinochloa crus-galli. 2. Translocation rate of bensulfuron was higher at 30/$25^{\circ}C$ than at 25/$20^{\circ}C$ and also in cv. Sangpung than in cv. Samgang, and C. serotinus showed highest translocation rate followed by the S. pygmaea and E. crus-galli. 3. In metabolism study, concentration of parent compound in rice plants was greater in cv. Sangpung which was susceptible to bensulfuron than in cv. Samgang. More amount of parent compound was distributed in shoots and root of C. serotinus and S. pygmaea than E. crus-galli. 4. It may suggested that sensitivity to bensulfuron between rice cultivars may be due to different inactivation metabolic ability and phytotoxicity of rice increased at high temperature since higher amount of bensulfuron was absorbed. Higher herbicidal activity of bensulfuron may caused by higher absorption and translocation in three weed species at high temperature.