• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.1
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• pp.15-24
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• 2006

This study was conducted to make a rapid and easy determination for the fertility of liquid pig manure as fertilizer by investigating the contents, and correlation coefficients of various nutrients. Samples were collected from 118 local pig farms in the western area of Jeju in Korea. Electrical conductivity(EC), dry matter(DM), $NH_4-N$ and minerals were determined and the relationships among them were examined. The collected liquid manure samples from 118 pig farms were classified according to the level of DM contents ;< 3% (92 farms), $3{\sim}6%$ (18 farms), $6{\sim}9%$ (5 farms) and>9% (3 farms), based on the collected data, most of the liquid manure coming from the local pig farms contain small amount of dry matter. The dry matter contents appeared highly correlated(p<0.01) with EC, $NH_4-N$, T-P, Ca, Mg and Na, except for K. In addition EC was proportional to $NH_4-N$, T-P, Ca, and Na except fer Mg. The fertilizer component ratio of $NH_4-N$, P and K in liquid pig manure were not constant, resulting in low efficiency for fertilizer. However, the toxic heavy metals of Cu etc. were below the criteria of organic fertilizer and soil contamination evaluation. Therefore, we concluded that both dry matter content and electrical conductivity could be used as an indicator for evaluating the fertility of liquid pig manure.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.1
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• pp.35-41
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• 1987

Nitrate nitrogen was absorbed dominantly among the inorganic nitrogen nutrients by tobacco plant. Transport and reduction of $NO_3-N$ in plant tissue were the important metabolism for supplying synthetic N compounds to developing tissues during growth period. Under field and environment-controlled condition tobacco plants were grown and seperated to leaf tissues at stalk positions for investigation of nitrogen transport and assimilation ability during period of rapid vegative growth. The results of studies were summarized as follows: 1. $NO_3-N$ absorbed from roots was transported as inorganic nitrogen through the vascular tissue of leaf veins as resulting from the high $NO_3-N$ ratio of the nitrogen content in leaf veins, but these ratios in mesophyll tissue of the same leaf laminae decreased remarkably in disregard of higher accumulation of nitrogen being compared to midvien. 2. Mesophyll tissue of mature leaves appeared higher value of nitrate reductase activity (NRA) comparing with other tissues, stem, leaf vien, and meristmatic tissue at emergence point with young leaves. 3. Matured leaves at lower position being reducing nitrate nitrogen vigorously observed thick laminae and kept high amount of water in them. 4. Mature leaves of young plant reduced $NO_3-N$ vigorously for supply synthetic N compounds to meristmatic tissues at growing point by the reason of narrow and few leaves at young stage, but in advancing growth period NRA of mature leaves along upper position reached to lower value. This appearence attributed to distribution of organic-N compound demanding for growth to increasing numbers of wide leaves.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.2
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• pp.109-115
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• 2004

To elucidate the effects of composted pig manure on soil biochemical properties, composted pig manure was amended in a sandy loam soil and Chinese cabbage was grown. Composted pig manure treatments included 8, 29 and $57Mg\;ha^{-1}$ for CM-08, CM-29, and CM-57 plots, respectively. Biomass contents and enzymes activities in the non-rhizophere soil were measured. Activities of protease, phosphomonoesterase and dehydrogenase in the plot CM-57 increased to 2.3, 1.6, and 2.4 fold as compared with those of the control plot. Soil microbial biomass contents increased in proportion to the application rates of compost and biomass C, N, and P in the plot CM-59 were 4.3, 3.4, 2.8-fold higher than those of control p1ot(no fertilizer), respectively. During cultivation of Chinese cabbage, biomass C and N were higher in the middle growth stage, although biomass P was the highest in the early growth stage. The average ratio of biomass C:N:P was 11:2:1, and proportion of biomass C and N in the soil organic C and N was 1.1 and 3.6%, respectively. Activities of protease and dehydrogenase had significant correlations with biomass C and P.

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.3
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• pp.167-172
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• 1990

Some of soil properties already known were selected for the determination of their effect on soil moisture characteristics. Total number of 2,808 representative samples from all over Korea with the exception of Jeju Island were investigated. 1. Available water contents were 4.7 for S, 7.7 for LS, 13.2 for SL, 17.7 for L, 19.2 for SiL, 15.9 for CL, 14.5 for SCL, 18.7 for SiCL, 17.3 for SiC, and 14.9% for C, respectively. 2. Simple regression analysis showed that field capacity and available water content were most strongly associated with sand content in coarse-textured soils, and with organic matter content in fine-textured soils, whereas permanent wilting point was closely associated with clay content. 3. Available water was strongly associated with silt content and also significantly with field capacity, but either not at all or negatively with permanent wilting point. 4. Prediction equations for available water and field capacity were drown out from known soil properties, which can be used for each textural class.

• Current Research on Agriculture and Life Sciences
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• v.6
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• pp.7-12
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• 1988

This study was conducted to establish the most appropriate transplanting time which can attribute to increase of aromatic substances in tobacco variety, Hyangcho, maintaining its original aroma. The highest content of total alkaloid, total nicotine and total nitrogenous compounds were observed in the late transplanting time such as July 5, showing 4.16%, 3.83% and 3.68%, respectively. However, the petroleum ether extract was highest in the early transplanted one such as April 5, showing 5.77% and total sugar content, 12% in April 20. The content of petroleum ether extract decreased as the transplanting time delayed. The early transplanting of Hyangcho on April 20 under vinyl mulching showed the increase of fatty acid content, but the decrease of non-volatile organic acids such as malic and citric acids than those of the conventional transplanting time on March 5. The earlier transplanting time also increased the content of volatile acids such as 2,3-methylbutanoic acid and 3-methyl-pentanoic acid, which seem to be related to tobacco aroma.

• Korean Journal of Weed Science
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• v.2 no.2
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• pp.114-121
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• 1982

Sagittaria pygmaea Miquel is widely infested and is the most dominant perennial weed in paddy field in Korea. This study was carried out in order to clarify the factors influencing tuber production and the competition ecology. The tuberization capacity in the paddy field transplanted with the small seedlings of rice was higher than in the paddy field transplanted with the vigor seedlings of rice. The stage which rice plants were most damaged by S. pygmaea plants was the period from 31 to 37 days after transplanting. According to the increasing of Eleocharis acicularis Roem. in the condition of rice cultivation, the number of S. pygmaea plants was remarkably reduced. Small size tubers planted within deep soil produced less tubers than large size tubers did. The number of plants and tubers were remarkably increased under the high levels of fertilization. Phosphorus was essential as well as nitrogen for tuberization. And the tuberization capapcity was different with the organic matter content in soil and with the soil moisture.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.1
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• pp.20-25
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• 1996

This survey was conducted to investigate the chemical properties of soils cultivated medicinal plants. The soils were collected at 254 sites(Angelica gigas : 81, Astragalus membranceus : 38, Platycodn glandiflorum : 36, Paeonia albiflora : 34, Codonopsis lanoceolata : 32, Ligusticum chuanxiong : 17. Bupleurum falcatum : 16, respectively) throughout the country by 0-15cm depth. The chemical properties of soils were pH 5.6, O.M 3.0%. Av.$P_2O_5$ : 405 mg/kg, Ex.K : $0.67cmol^+/kg$, Ex.Ca : $6.3cmol^+/kg$, Ex.mg : $1.6cmol^+/kg$. The percentage distribution of pH on the basis of soil sample numbers were much more at the 5.1-6.0 range than any other ranges, especially those of below pH 6.0 were 83-91% for Angelica gigas, Platycodn glandiflorum and Codonopsis lanoceolata. The distribution of OM and Av.$P_2O_5$ in soils were much at the 2.1-4.0% and above 500mg/kg ranges, respectively. And the content of those in soils cultivated with Platycodn glandiflorum were lower than any other medicinal plants. The distribution of exchangeable cations in soils were much at the 0.2-0.8, 2.1-4.0 and $0.5-2.0cmol^+/kg$ of Ex.K. Ca and mg. respectively, and the contents were higher in soils cultivated Astragalus membranceus. and lower in soils cultivated Platycodn glandiflorum and Codonopsis lanoceolata than any other samples.

• Journal of Korean Society of Forest Science
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• v.103 no.4
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• pp.528-536
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• 2014

The aim of this study was to investigate the damage characteristics induced by winter freezing of evergreen broad-leaved trees distributed in urban area of warm temperate forest zone, which are gaining increased interest recently as climate change. The results of the study indicated that, as for 'stem injury', Camellia japonica Linne (59.6%) had the weakest damage, while Ternstroemia gymnanthera Sprague (83.3%) had the most severe damage. By the visual evaluation of freezing injury according to the characteristics of plantations environment, the observations of single planting (p<0.01) in planting method had weaker damage than those of group planting, the observations of under tree (p<0.001), plain (p<0.001), and organic matter plenty (p<0.05) in plantations characteristics had significant differences with relatively weaker damage than the observations of open space, slop, and scarcity, respectively. Tree height (-0.432) and crown width (-0.470) among growth factors were negatively correlated with the severity of damage, respectively. Therefore, the selection of tree species is vital for the successful creation of these urban forested area by making considerations of planting environment, and further research on evergreen broad-leaved trees is needed in this aspect.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.2
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• pp.160-166
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• 1989

This study was conducted to investigate whether egg-shell may be used as a mineral sourceor leavening agent in breadmaking. In Korea the waste volume of egg shell has been estimated at about 28,694 tons per year. Carbon dioxide generation maxima were established for barking powder$(153{\pm}3ml/g)$, egg-shell(205in reaction with lactic acid) and yeast$(115{\pm}3ml/sugar\;g)$. Gas release time required for each substance to reach $CO_2$ maximum was, for baking powder 7 minutes, for egg-shell 45 mins and for yeast 240 mins. Particle size of egg-shell in breadmaking was suitable more than 20 mesh (-). When egg-shell only was added to the basic formular without including lactic acid, no leavening effect was observed. However, when lactic acid and egg-shell were used together, the leavening effect was more or less equivalent to that of yeast(control). Addition of egg-shell was found to increase calcium content of bread products without noticeable altering flavor, as compared with control. Joint use of egg-shell was organic acids in breadmaking was shown to have potential in time saving, volume increase and yeast saving.

• Journal of Korean Society of Forest Science
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• v.80 no.4
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• pp.436-444
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• 1991

To increase both the production of mushrooms and the usages of the residues (used media) for roughage, the pinchips(PC) and sawdusts(SD) of three Korean oak species were tested as cultivating media for Lentinus edodes with varing the composition of the media. The results are as follows. 1. Organic acids(tannic acid and citric acid), which were added in the PC medium to enrich the quality of mushrooms, did not increase the growths of the mycelia and the quality. 2. The mushrooms were able to be harvested from six months after beginning the cultivation. No significant differences were found among the qualities of the mushrooms produced by various treatments. 3. The contents of crude proteins(1.82-4.55%) in the used media were higher than those in woods (c.a. 0.7%), and the total digestible nutrients (44.0-46.0%) in the used medium were not much different from those in rice straws (c.a.48.0%). 4. The contents of some essential amino acids (methionine in the used medium of the tannic acid added PC or S.D. and isoleucine, phenylalanine and lysine in the used medium of the untreated PC or SD) were higher than those in the control (raw media). The contents of a few other essential amino acids (threonine, valine and arginine) were lower in the used media. Most nonessential amino acids in the used media, particularly in the used bed-log, appeared to decrease than those in the control.