• Proceedings of the Korean Society of Grassland Science Conference
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• 1999.06a
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• pp.89-90
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• 1999

페레니얼 라이그라스(Lolium perenne L.)의 질소공급형태에 따른 저장질소의 함량과 재생기간 중 저장질소의 이용 및 재생활력을 구명하고자 수경재배 하였다. (NH$_4$)$_2$SO$_4$, KNO$_3$, Urea, Organic-N 및 NH$_4$NO$_3$의 서로 다른 질소형태로 각각 1mM/week을 4주간 공급하여 건물생산량을 보았고, 예취 후 각각의 질소 형태로 4mM/40days동안 공급하여 흡수된 질소의 함량 및 잔여기관내 축적된 질소의 함량을 관찰하였으며, 예취 후 저장된 질소에 의한 재생활력을 보기 위해 0.2mM NH$_4$NO$_3$의 형태로 동일하게 공급하였다.(중략)

• Journal of the Korean Solar Energy Society
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• v.26 no.1
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• pp.73-79
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• 2006

The integration of PV modules into building facades or roof could raise PV module temperature that results in the reduction of electrical power generation. Lowering operating temperature of PV module is important in this respect, and PV module temperature should be considered more accurately, for building-integrated PV(BIPV) systems in predicting their performance. This paper describes a BIPV solar roof design and verifies its performance through experiment In relation to the effect of ventilation in space between PV module and roof surface. The results showed that the ventilation in the space had a positive effect in lowering the module temperature of the BIPV solar roof that enhanced the performance of its electricity generation.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.1
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• pp.45-50
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• 2002

This experiment was conducted to establish the intensive Grazing system through the improved pasture utilization of the Hanwoo beef cattle. Intensive grazing period, 2 to 3 days was compared to conventional rotation-grazing period, 5 to 6 days as control. The intensive grazing system which has 2 to 3 days of grazing period, increased forage DM yield(7.33t/ha) by 17% compared to control(6.28t/ha), and contributed to stabilization of the seasonal productivity through the increased DM yield after August. Plant height, feed intake and efficiency of grazing was increased in intensive rotation.

• Journal of Korean Society of Forest Science
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• v.104 no.3
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• pp.390-396
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• 2015

This study was carried out in order to closely examine quality index by shading level of 2-year-old (1-1 seedling) container seedling of Daphniphyllum macropodum which is known as the species of having shade tolerance that is evergreen broad leaved tree in the warm temperate region. The shading treatment was regulated with the shading level of full sunlight, and 35%, 55%, 75%, 95% of full sunlight. As a result of surveying growth according to the shading level, both height and root collar diameter were surveyed to be the highest with 45.1 cm and 8.22 mm, respectively, under 75% of shading. The next was surveyed to be 43.2 cm & 8.05 mm and 42.5 cm & 7.98 mm, respectively, in order of 35% and 55% in shading. Leaf, shoot, root, and whole dry mass production were the highest under 75% of shading. The next was higher in leaf, stem, and whole dry mass production under 55% of shading. A root was higher under 35% of shading in the next. H/D ratio was the range of 5.29~5.35 under the 35~75% shading that showed the relatively high height and root collar diameter. T/R ratio was the lowest with 1.17 under 35% of shading. It was 0.41 under 95% of shading as for LWR, 0.24 under 75%-95% of shading as for SWR, and 0.46 under full sun and 35% shading as for RWR. QI was the highest with 3.74 under 75% of shading. As a result of surveying the whole experiment, it is concluded that the production of D. macropodum seedling is more effective under 75% shading

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.3
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• pp.278-286
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• 2019

Sesbania, an annual herb, is known for its high forage value and salt tolerance. It has merits as a forage crop that is adaptable to reclaimed land in the Republic of Korea. Therefore, we collected Sesbania genetic resources from the Republic of Korea and other countries, and conducted experiments to evaluate their potential as a forage crop in Korean climate and soil conditions. In the preliminary experiments, 15 genetic resources which were able to set seeds in Korean environment were selected out of a total of 46 collected genetic resources. Among 15 genetic resources, SL13 was the tallest and it was followed by that of SC04, SR01 and SE07. The accessions with the earliest flowering started flowering 101 days after sowing and set seed in early August. Fifteen accessions were evaluated for their salt tolerance at germination stage based on germination rate and growth of germinated seedlings at 0 mM, 150 mM and 300 mM NaCl concentrations. Five genetic resources like SC04, SL13, SS20, SS24 and SR01 were selected to be tolerant to NaCl treatment. Forage value was evaluated based on crude protein, acid detergent fiber, neutral detergent fiber and in vitro dry matter digestibility. The forage value of leaves was significantly higher than that of stems, and the forage value of the stem was slightly better than that of rice straw. The forage value of leaves of all the genetic resources was higher than grade 1 by the American Forage and Grassland Council grade. Among five selected genetic resources, the relative feed value of SC04 was the highest and it was followed by that of SS20, SL13, SS24 and SR01.

• Korean Journal of Weed Science
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• v.18 no.2
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• pp.122-127
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• 1998

This experiment was conducted to investigate the response of the fertilizer three factors on the growth of Alopeuclus aequalis Sobol. var. amurensis(Kom.) Ohwi. The growth of Alopeuclus aequalis Sobol. var. amurensis(Kom.) Ohwi. such as plant height, tiller number and dry matter production were vigorous on the plot fertilized with phosphate(P, NP, PK, NPK). The main effect of plant height elongation and dry matter production were significant for phosphate and nitrogen, and their interaction effect was recognized, too. Tiller growth and panicle number were mainly affected by phosphate. The growth of Alopeuclus aequalis Sobol. var. amurensis(Kom.) Ohwi. depended mostly on phosphate among the fertilizer three factors. The effect of nitrogen fertilizer was very different according to phosphate fertilizer treatment.

• Korean Journal of Environmental Agriculture
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• v.19 no.3
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• pp.213-217
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• 2000

In order to select more proper plants for phytoextraction at the heavy metal polluted areas, 11 species of non-edible plants were cultivated at the cadmium(Cd) and Lead(Pb) treated soils and analyzed the content of the absorbed Cd and Pb in each part of plants. Plants include three fibers(Linum usitatissimum, Cannabis sativa, Gossypium spp.), three flowers(Calendula officinalis, Rhododendron lateritium, Portulaca grandiflora), and five trees(Pinus thunbergii, Magnolia kobus, $Populus\;nigra\;{\times}\;P.$ maximowiczii, Euonymus japonica, Fraxinus rhynchophylla). Yield of tree species were higher than that of fiber and flower species. Cd and Pb were highly accumulated in root rather than leaves and stems. The Cd content of plants was in the order Portulaca grandiflora > Calendula officinalis > Gossypium spp. > Linum usitatissimum, Pb was Cannabis sativa > Linum usitatissimum > Fraxinus rhynchophylla. Total absorbed Cd by each plant was in the order $Populus\;nigra\;{\times}\;P.$ maximowiczii > Euonymus japonica > Rhododendron lateritium, but Pb was $Populus\;nigra\;{\times}\;P.$ maximowiczii > Rhododendron lateritium > Euonymus japonica. Total absorbed Cd and Pb contents in plants were negatively correlated with the residual Cd and Pb in the treated soils. It was estimated that $Populus\;nigra\;{\times}\;P.$ maximowiczii, Euonymus japonica, Fraxinus rhynchophylla, and Rhododendron lateritium were the most effective species for phytoextraction in the polluted area considering yield and heavy metal uptake.

• Korean Journal of Soil Science and Fertilizer
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• v.13 no.3
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• pp.85-91
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• 1981

In order to evaluate effectiveness of zinc source on uptake of zinc by rice plant, a pot experiment carried out using ZnEDTA and $ZnSO_4$ in a glasshouse. The results obtained were summarized as follows: The effectiveness of zinc source on uptake of zinc by rice plants was different with different soil. Namely ZnEDTA was more efficient than $ZnSO_4$ in increasing yield of zinc and concentration of zinc in the plant grown on Jecheon calcareous soil. In case of Keumgok acid soil, however, no superiority of ZnEDTA treatment was found. The plant growing status of ZnEDTA treated calcareous soil was also shown that larger number of tillers per hill, bigger height of the plant and good yield of dry matter production than those of the plant grown on $ZnSO_4$ treatment. Regardless of the zinc source, smaller number of tillers per hill, shorter height of the plant, and the lowest yield of dry matter were shown in the treatment of zinc and straw mixed with both soils. It seemed that more applied zinc was to be fixed by the straw application resulting in poor zinc yield. The extent of the zinc fixation showed markedly in Jecheon calcareous soil.

• Korean Journal of Environment and Ecology
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• v.20 no.4
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• pp.425-435
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• 2006

The objectives of this research were to investigate the drought resistance as well as the growth of Wisteria floribunda seedlings with the soil water conditions. The seedlings for the research were grown in pots with strict water content control on a frame located outdoors. During the experiments, the soil water contents were adjusted to 5, 10, 20, 30, 40, 50, 60, and 70%. In addition, the effects of Rhizobium inoculation on the growth of seedlings were investigated. The experimental results are summarized as follows: 1. The seedlings in the pots with 5% soil water content withered to death due to the water stress. Withering or any distinct growth was not observed from the seedlings in the 10% soil water content. It can be inferred from these results that about 5% of soil water content is the wilting point of W. floribunda seedlings and about 10% is the critical soil water content of its growth in this experiment soils. Therefore, it seems that W. floribunda possesses a good drought resistance. 2. From the analyses of the main growth parameters such as stem elongation, diameter growth, leaf area growth and total dry weight, it was found that the seedling growth can be improved with increasing soil water contents. The relation between each growth parameter(Y) and the soil water contents(W) was well described by a quadratic equation, $Y=a+bW+cW^2$. 3. In soil water contents higher than 20%, the seedling growth(Y) was remarkable along with-its extended growing period, and related to the growing period(D) by a quadratic equation, $Y=a+bD+cD^2$. 4. The artificial inoculation of Rhizobiun promoted the growth of Wisteria floribunda seedlings. 5. Rhizobium was found to be more readily inoculated and to form more root nodules compared to seedlings grown in higher soil water contents.

• Korean Journal of Agricultural Science
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• v.26 no.2
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• pp.25-32
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• 1999

An in vitro study was conducted to examine the effects of the addition of activated charcoal (AC) on the ruminal fermentation characteristics, nutrient disappearance, and ruminal gas production. AC was added at the levels of 0.00, 0.25, and 0.50 % to each of the four types of diets (roughage/concentrate ratio : 8/2, 6/4, 4/6 and 2/8), respectively. Although not significant, ruminal pH tended to increase by adding AC, and as the concentrate level increased, ruminal pH decreased (P<0.05). Acetate concentration and acetate/propionate molar ratio tended to decrease in AC diets. but molar % of propionate tended to increase by the addition of AC. Ruminal degradation of dry matter, crude protein, NDF, ADF, and hemicellulose in AC diets tended to increase than in non-AC diet, however, no tendency in ruminal degradation of crude fat was observed. As the concentrate level increased, rumunal degradation of dry matter and nutrients in AC diets increased significantly(P<0.05). Ruminal gas production tended to decrease in the 0.50 % AC diets, however, it tended to increase in high roughage diets. Although there appeared some beneficial effects in adding AC to ruminant diets in this study, more works should be done with AC before we can make clear conclusion on the use of AC in the ruminant diets.