• Journal of Korean Society of Forest Science
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• v.78 no.3
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• pp.314-322
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• 1989

For the improvement of nursery condition and the study of eco-physiological characteristics of Pinus koraiensis(2-2) seedlings, the primary productivity was investigated and the growth characteristics and their correlationship were analyzed from May to September in 1987. Seedlings used in this study were grown at the nursery of Experimental Forestry of Kyung Hee Univ. The installation of experimental plots were divided into control plot (100%), 63%, 37% and 19% relative light intensity, and each relative light intensity plots were split into $15{\times}15/m^2$, $12{\times}12/m^2$, $9{\times}9/m^2$ and $6{\times}6/m^2$ plnting density by randomized black design method. To take into account the edge effect of plant population, material were selected from each plot by random sampling at 30 days interval. Each sampled material was divided into leaf and stem drived in a drying oven at the temperature of $85^{\circ}C$ until it had constant weight and weighed. and leaf area was surveyed. Growth analysis for RGR and NAR was done by Blackman method and correlation coefficient were investigated between RGR and NAR by analyzing the dry matter production and growth characteristics of the material, cultivated on the experimental nursery under the condition of different treatment the obtained result were as follows : 1. The increasing rate of dry matter was similar at early stage of growth, but not at late stage. 2. Leaf area growth was the maximum value at 63% relative light intensity and the minimum at 19% RLI 3. The value of RGR was the highest on June under $6{\times}6/m^2$ planting density in 63% relative light intensity, the lowest on September under $12{\times}12/m^2$ of 19% relative light intensity. 4. The change NAR decreased in early stage of growth, while it increased on August and September, The value of RGR on June under $6{\times}6/m^2$ planting density in 100 light intensity was the highest, and on September under $12{\times}12/m^2$ planting density in 19% relative light intensity was the lowest. 5. Regression and correlation between RGR and NAR showed significantly positive.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.1
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• pp.30-34
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• 1984

A pot experiment was conducted to investigate the dry matter weight of soybean plant, fertilization efficiency, and the changes of p uptake with different p application levels in cultivated and uncultivated soils controlling the soil moisture content to 2 levels. 1. The effect of irrigation was higher in cultivated soil than in uncultivated soil, and was higher in larger amount of p application than in small amount of p. 2. Efficiency of phosphate fertilization for soybean growth was higher in cultivated soil compared with uncultivated soil, and increased by irrigation to optimum soil moisture content for crop growth. 3. Adjustment of soil moisture content to optimum level for soybean growth increased the concentration of phosphate in plant and decreased the content of phosphate in soil. Therefore, it was obvious that soybean plant absorbed the high amount of p in the optimum soil moisture level and in large amount of p application.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.4
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• pp.271-276
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• 2003

A Jeju local variety of Italian millet (Setaria italica Beauvois) was grown at five seeding rates (6, 9, 12, 15 and 15 kg/ha) from May 1 to August 25, 2003 at Jeju to determine influence of seeding rate on agronomic characters, forage yield and quality. Days to flowering increased from 89 to 96 days as seeding rate increased from 6 to 18 kg/ha. The plant height increased from 128 to 148cm as seeding rate was increased from 6 to 12 kg/ha and then decreased to 131cm at a rate of 18 kg/ha. With increasing seeding rate, stem diameter, number of leaves, number of nodes, leaf width and weight per plant decreased but leaf length had the same trend with plant height. As seeding rate increased from 6 to 12 kg/ha, fresh furage, dry matter, crude protein, and total digestible nutrients (TDN) yield increased from 35.93 to 54.83 MT/ha, 10.49 to 17.43 MT/ha, 0.94 to 1.79 MT/ha and 5.33 to 9.27 MT/ha, respectively, and then decreased with further increased seeding rates. Crude protein, either extract, nitrogen free extract, and TDN content increased 9.0 to 12.01％, 1.3 to 1.8%, 45.6 to 47.8% and 50.8 to 55.0%, respectively, but crude fiber content decreased 35.2 to 30.0% and crude ash declined 5.8 to 8.4% as seeding rate increased from f to 18 kg/ha. The optimum seeding rate to obtain the highest forage yield was estimated to be 12 kg/ha.

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.1
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• pp.55-60
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• 1988

To develop soybean inoculant the effects of inoculation with selected Rhizobium japonicum strains were tested in the field, and the results were as following. 1. With the inoculation of selected strains, increase of nodule number, nodule weight and nitrogen fixing activity were observed with or without applying N-fertilizer. 2. Chlorophyll contents was increased and senescence of plant was delayed with the inoculation of selected strains in case without applying N-fertilizer. But there was little difference of chlorophyll contents in case with applying N-fertilizer. 3. There were little differences of plant height and number of nodes, and some increase of plant stem dry matter and number of pods with inoculation of selected strains. 4. The mean yield of inoculation group (363-374kg/10a) was increased by 8-11% comparing to the uninoculated group (337kg/10a) in case without applyiag N-fertilizer. The mean yield of inoculated group (368-384kg/10a) was increased by 9-14% also in case with applying N-fertilizer.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.2
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• pp.98-105
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• 2020

This experiment was conducted to a comparison of the productivity according to variety and forage quality by plant parts of imported silage corn (Zea mays, L) in Pyeongchang. The corns evaluated in this experiment were 8 varieties (P1184, P1151, P1194, P1543, P1345, P1429, P1443, and P2105) introduced from the United States, Pioneer Hybrid Co. The harvested corn was divided into 5 plant parts (leaf, stem, cob, husk, and grain), and the ratio of each part was calculated using dry weight and the feed value was analyzed. The emergence rate of corn was generally good except for the P1151 and P2105 varieties. The average tasseling date was July 24^th and the silking date was July 27^th, but the P2105 variety was late to July 28^th and August 1^st, and the remaining varieties were similar. P1345 was the highest (289 and 123 cm), and P1151 varieties were the lowest (267 and 101 cm) in the plant and ear height. Disease resistance was low in P1184, P1443 and P1429, and P1197 and P1345 were high. In the case of stover, the dry matter (DM) content was the lowest at 19.6% in the P1151 and the highest at 24.9% in the P1429. DM content of ear was the highest in the P2105 (55.5%), and P1184 (54.2%) and P1345 (54.3%) were also significantly higher (p<0.05). The DM yield of stover of P2105, P1429 and P1194 varieties was significantly higher (p<0.05), and ear yield of P2105, P1345 and P1443 was higher. The proportions of each part of plants (leaf, stem, cob, husk, and grain) divided by 5 was high, with 50-60% of the ear(grain+cob) ratio. The ratio of husk and cob was roughly similar, and the leaf and stem part showed a ratio of about 20%. The crude protein (CP) content was highest in leaf, followed by grain. The CP content of the stem was the lowest, and the husk was not significantly different among the varieties (p>0.05). The acid detergent fiber (ADF) content was similar to the rest parts except grain, but the leaf part tended to be lower, and other parts except the stem and leaf showed no significant difference between varieties (p>0.05). There was no significant difference in NDF (neutral detergent fiber) content in husk, but there was a difference between varieties in other parts (p<0.05). In addition, there was a special difference by plant parts for each variety, P2015 on the stem, P1197 on the leaf, P1151 on the cob, P1197 on the husk, and P1197 on the grains with high NDF content. IVDMD (in vitro dry matter digestibility) was not significantly different between stems and grains, but there was a difference between varieties in cobs and husks. According to the results, DM yield of P2105 variety was the best in the experiment, and the ratio of grain was excellent in P1543 and P1345. In addition, it was found that the feed value was higher in the leaves and grains, and the leaf and stem had higher feed values than husk or cob.

• Journal of Environmental Science International
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• v.15 no.5
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• pp.405-415
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• 2006

Sixteen soil samples around six areas (residental area, traffic area, power plant area, incineration area and factory area) where the stationary and mobile sources of polycyclic aromatic hydrocarbons (PAHs) are estimated to be emitted in Jeju City, were collected during Feburuary to March, 2004, and analyzed for 16 PAHs recommended by US EPA as primary pollutants to investigate their distribution characteristics. The concentrations of total PAHs (t-PAHs) and total carcinogenic PAHs $(t-PAH_{CARC})$ in soils of Jeju City were in the range of $21.7\sim264.2ng/g$ on a dry weight basis with a mean value of 87.2 ng/g and $6.3\sim118.0ng/g$ with a mean value of 33.4 ng/g, respectively. The concentrations of t-PAHs were low in comparison with those in soils of other domestic and foreign countries. The mean concentrations of t-PAHs and $(t-PAH_{CARC})$ with area decreased in the following sequences: traffic area> incineration area > factory area > power generation area > harbor area enli residental area. The correlation between t-PAHs and $(t-PAH_{CARC})$ were very high $(\gamma^2=0.9701)$, indicating that $(t-PAH_{CARC})$ concentration increases in proportion with t-PAHs. Comparing the distribution ratio of ring PAHs with area among 16 PAHs, it decreased in the order of 4-ring > 5-ring > 6-ring > 3-ring > 2-ring in all the areas except for harbor area. whitens for harbor area it was similar among 3-, 4- and 5-ring with high value. Low and no correlations between t-PAHs and soil compositions (organic matter content and particle size distribution) were observed, which is considered to be caused by the complex factors, such as the loading and characteristics of PAHs and diverse soil environment change, etc. From the examination of the three PAH origin indices, such as LMW/HMW (low molecular weight $2\sim3$ ring PAHs over high molecular weight $4\sim6$ ring PAHs), phenanthrene/anthracene ratio and fluoranthene/pyrene ratio, it can be concluded that the soil PAH contaminations were ascribed to strong pyrogenic origin in ail areas except for harbor area and to both pyrogenic and petrogenic origins.

• Korean Journal of Environment and Ecology
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• v.25 no.1
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• pp.17-30
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• 2011

This study has analyzed the vegetation composition in the areas using different slope revetment techniques of riverbanks, in a way to improve the vegetation induction in the future considering the ecological aspects of the induction in Garaeyoul Village, Gangdong-gu, Seoul. The result of the vegetation distribution in each different slope revetment technique was analyzed, that the naturalized herb was dominant in the pole block accounting for 70.7%, while native herb was dominant in the lawn block occupying 48.5% and in the crib block occupying 55.7%. The vegetation coverage measured by different slope revetment techniques was highest in the crib block(average 97.5%), followed by the lawn block(average 95.3%) and pole block(average 27.9%). The vegetation base area was the most wide in the crib block and the most narrowest in the pole block. The result of community analysis in areas using different slope revetment techniques, dry herbs and vine herbs were dominated and the coverage was very poor in the pole block. In the lawn block, the barb was fragmented into narrow areas due to the blocks, which prevented the creation of large-scale plant communities. In the crib block, Miscanthus sacchariflorus, Fescue arundinacea and Aster pilosus, which also consisted of large-scale communities. Average dry weight was also measured by each slope revetment technique. The weight was heaviest in the crib block with $187.63g/m^2$, followed by the lawn block($137.65g/m^2$) and pole block($6.75g/m^2$). The soil moisture contents in the crib block and lawn block was 16.3% and 15.2%, respectively, while that of the pole block was 4.7%, which revealed the highly dry condition of the pole block soil. The analysis result of soil chemical property showed that there was little difference in soil texture, soile acidity(pH), and exchangeable ion content, however, the soil organic matter(OM) content and available $P_2O_5$ were highest in the pole block. In the future, in order to induce more vegetation into river banks and walls, a proper construction method should be applied so that the vegetation area can be expanded as much as possible, considering the safety of the banks.

• Korean Journal of Soil Science and Fertilizer
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• v.3 no.1
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• pp.17-21
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• 1970

To determine the effects of the silicate and the phosphate on the rice seedlings, 200 grams dry soil of the paddy field taken in the petri dish of 15cm diameter were treated with three levels of silicate(wollastonite) and phosphate. And the same amounts of nitrogen and potash were added constantly to each treated petridish. 100 grains of rice of which variety is Nongrim 25 were sown on each treated petridish simultaneously. After five times continuous culture, the rice plants and the soil were analyzed chemically and the results obtained are summarized as follows: 1. Dry matter weight of the rice seedlings was significantly increased to the increased phosphate absorption, on the other hand that was decreased when the silica absorption was increased. 2. The higher the available phosphate content in the soil after the experiments, the lower the silica content as well as absorption by the plant, and the $SiO_2/P_2O_5$ ratio in the plant was significantly decreased. 3. By the wollastonite application, the available silica, the exchangeable calcium in the soil after the experiment, and the silica content as well as silica absorption and $SiO_2/P_2O_5$ ratio in the rice plant was significantly increased. 4. Higher correlation coefficient was obtained between the exchangeable calcium amount and the silica content or silica/phosphate ratio in the rice plant than the available silica content in soil itself. 5. It is possible to control the silica/phosphate ratio in plant by the control of the silica/phosphate ratio in soil. 6. The relation between the silica/phosphate ratio in plant (y) and the available silica/phosphate ratio in soil (x) was $y=0.665+1.420x-0.0825x^2$ and the goodness of fit(r) was 82%.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.7
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• pp.986-993
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• 2001

In balance experiments with rats either 25 or 50% of the casein protein in the control diet was replaced with one of the following eight sun-dried tropical biomass products: water spinach plants (WS) (Ipomoea aquatica Forsk), leucaena leaves (LL) (Leuceana leucocephala), duckweed plants (DW) (Lemma minor L.), groundnut foliage (OF) (Arachis hypogaea L.), trichantera leaves (Tric) (Trichantera gigantea), indicago leaves (Ind) (Indigofera hirsuta), mungbean foliage (Mb) (Phaseolus aureus), and cassava leaves (CL) (Manihot esculenta Crantz). The experiment included 102 rats with six individuals per treatment group. In three of the 16 biomass treatment groups, feed intake and weight gain of the rats were unacceptably low, and therefore they were excluded from the statistical evaluation, The crude protein (CP) content of the biomass products varied between 20.9% (Tric) and 33.2% (DW), whereas the content of NDF varied between 18.5% (Ind) and 32.2% (DW) of dry matter (DM). The total content of essential amino acids (g/16 g N) was comparable with that of alfalfa meal, except for GF and Tric, which were inferior. Between plant species, differences in dietary digestibility of organic matter (dOM) and CP (dCP) were observed (p<0.001). Also, the replacement level negatively influenced dOM and dCP (p<0.001). The lowest values for dOM (p<0.001) were observed for diets including biomass products with the highest content of NDF (OF, Tric, Mb, LL). Digestibility of CP was negatively affected by level of protein replacement. Significant (p<0.001) differences were found in N-retention and biological value among diets with different biomass products. The most favourable overall results were obtained for DW, WS and CL. The main factors affecting the nutritive value of the diets tested were their NDF content, dCP and AA profile of the biomass. Also antinutritive component(s) may have influenced the process of digestion and metabolism of some of the biomass products.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.2
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• pp.5-14
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• 2017

Humic acid was used soil amendment or functional fertilizer in Korean agriculture, and its cation exchangeable capacity was high enough to increase soil buffering from plant toxicant. This study was conducted to evaluate effects of humic acid powder (HA) on composting of livestock manure (LM) and of its application on growth of lettuce. Treatments were designed as follows; livestock manure compost (LM+sawdust+bark+castor meal; Control), control+0.1% HA (0.1% HA), control+0.5% HA (0.5% HA), control+1.0% HA (1.0% HA), control+3.0% HA (3.0% HA), and control+5.0% HA (5.0% HA). The changes of temperature, water content, organic matter content, total nitrogen and ratio of organic matter and nitrogen in HA treatments were similar to those of control. Although pH of 3.0% HA and 5.0% HA blending with HA and LM was lower than those of others, it unaffected by HA blending during composting. Humic acid content of HA treatments was increased by 1.7~4.4 folds than that of control. As compared with odor index, 3.0% HA and 5% HA were decreased than control for composting time. Application of 3.0% HA increased the dry weight of lettuce by about 7% than that of control.