• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.9 no.4
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• pp.179-195
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• 2004

The trophic state of the coastal waters of the southern part of Korea was assessed using biogeochemical data obtained from the National Marine Environmental Monitoring Program conducted by the National Fisheries Research and Development Institute for six years. The trophic state of different areas, analyzed by non-metric multi-dimensional scaling (MDS) analysis, could divide the areas into three groups. Masan Bay, with suboxic water masses and/or the highest concentrations of dissolved inorganic nitrogen and phosphorus occurred, was assessed as being in a hypertrophic state. Ulsan Bay, Onsan Bay, Busan and Jinhae Bay, located near strong point sources, were in a eutrophic state. Other areas, including Tongyong, Yosu, Mokpo and Jeju island, were evaluated as being in a mesotrophic state. During 1997 to 2002, the average values of excess nitrogen, which is the difference between the measured dissolved inorganic nitrogen (DIN) and the corrected DIN using the Redfield ratio, were positive at Ulsan, Onsan, and Busan, where there were inflows from polluted rivers. In contrast, those were negative values in Haengam Bay, Gwangyang Bay and nearby Yosu. This suggests that the limiting element for phytoplankton growth differed among sites. The time series data of excess nitrogen showed gradual decrease over time in the hypertrophic waters, but the opposite trend in the mesotrophic waters. This indicated that the ratio of nitrogen to phosphate varied according to the trophic state of the coastal waters. The enrichment of organic matter in sediment in eutrophic waters would disturb the normal pattern of biogeochemical cycling of nitrogen and phosphate. In order to assess the condition of the coastal environment, the benthic boundary layer should be considered.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.6
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• pp.391-398
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• 2003

Research was conducted to establish the leaf and petiole sap test to diagnose the nutritional status of tomato. The concentrations of $NO_3$, $PO_4$, K, Ca, Mg and $SO_4$ ions extracted from the leaves and petioles in the different positions in a plant were measured and compared with their corresponding inorganic contents in the leaves analyzed by the chemical method. The ionic concentrations in the leaf and petiole sap showed the different values depending on their positions in a plant. The leaves and petioles in the lower positions of a plant had higher concentrations of $NO_3$, Ca, Mg and $SO_4$ ions. In particular, there were greater changes of ionic concentrations and less increases in the leaf length and width from the 9th compound leaf down from the uppermost cluster. On the other hand, the leaflets in a compound leaf had the same ionic concentrations. Therefore, it appeared that the optimal sampling position of leaf and petiole for the sap test is the leaflets of the 9th compound leaf down from the uppermost cluster. A good correlation between the sap test and the chemical analysis of plant showed that the ionic concentrations in the leaf and petiole sap reflect the nutritional status of tomatoes.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.5
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• pp.587-593
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• 1995

Growth characteristics and aromatic constituents of wild and domesticated Codonopsis lanceolata grown in different regions were investigated to find the best cultural condition for quality improvement. The results were as followings: Air temperature of wild region was lower to 4~8 and soil temperature was also lower to 3 compared with domesticated region. Soil of wild region had about three times richer organic matter with lower pH. Chromosome number of wild and domestcated species was 2n=16, ovary number was 3, but seed number of wild species was 132 vs domesticated showing 62. Recovery yield of wild species grown wild region had 0.55%, besides that, the wild species grown in domesticated region had 0.34. But the domesticated species in wild and domesticated regions was the same as 0.28. Inorganic element contents of domesticated region showed much higher than that of wild region. Major aromatic constituents were specified in wild Codonopsis lanceolata as dimethyl benzene, 3-ethyl-5-2-(ethylbutyl)-octadecane, benzaldehyde, 14, 14-dimethyl-hexadecanoate, methylhexadecenoate of which was not detected in domesticated species.

• Korean Journal of Environmental Agriculture
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• v.39 no.2
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• pp.95-105
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• 2020

BACKGROUND: In this study, in order to verify the effects of supplemented organic amendment fertilizers recommended by the soil testing on cabbages, we used various amounts of organic amendment fertilizers. The amount of organic amendment fertilizers was decided by calculating each ratio of inorganic nitrogen, phosphorus, and potassium based on the recommended fertilizer composition. METHODS AND RESULTS: The cabbages subjected to treatments 1 and 2 showed similar or greater leaf colors (SPAD values), head heights, head widths, head weight, soil organic matter content, nitrate-nitrogen level, and conductivity after harvest, when compared with cabbages treated with chemical fertilizers. The phosphorus and potassium fixation in the soil were higher in the plot where cabbages were treated with chemical fertilizers, and the nutrient use efficiency was greater in the plots with organic amendments and mineral addition. CONCLUSION: The treatments 1 and 2 that were supplemented with 180-200% of nitrogen, 100-130% of phosphorus, and 185-250% of potassium in comparison to chemical fertilizers, applied by the inorganic ratios of nitrogen, phosphorus, and potassium can be used as organic amendment fertilizers for cabbages.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.380-386
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• 2011

Tip burn has been reported as one of the most serious physiological disorder in Chinese chives (Allium tuberosum Rottl.) cultivated in plastic film house. In this study, a physiography and chemical properties of 132 plastic film house soils were investigated to elucidate factors affecting tip burn symptom. Also influence of soil properties on tip burn was statistically determined by path analysis and association analysis including a chi-square test or logistics analysis. Probability distribution of inorganic aqueous species, such as ammonia (g) was calculated using MINTEQ program. Soil order and chemical properties, especially pH, exchangeable calcium and inorganic nitrogen, showed a significant relationship with tip burn of Chinese chives. Tip burn symptoms occur mainly in an alkaline soil classified as Alfisols. Result of linear regression and path analysis exhibited that formation of ammonia (g) from soil solution depend upon soil pH and were associated with ammonium resulting from soil organic matter or nitrate. These results indicate that tip burn symptom of Chinese chives is directly affected by ammonia gas originated from alkaline soil condition.

• Journal of Animal Science and Technology
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• v.64 no.1
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• pp.23-37
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• 2022

Thirty-six weaned piglets with an initial body weight (BW) of 8.43 ± 0.40 kg (28 days of age, ([Landrace × Yorkshire] × Duroc) were randomly assigned to 6 treatments for a 2-week feeding trial to determine the effects of different inorganic zinc (IZ), organic zinc (OZ) or combination of low crude protein diet (LP) and Mixed feed additive (MFA) on diarrhea score, nutrient digestibility, zinc utilization, blood profiles, organ weight, and fecal microflora in weaned piglet diet. The pigs were individually placed in 45 × 55 × 45 cm stainless steel metabolism cages in an environmentally controlled room (30 ± 1℃). The dietary treatments included a negative control (NC), positive control (PC; zinc oxide, 1,000 mg/kg), T1 (IZ : OZ, 850 : 150), T2 (IZ : OZ 700 : 300), T3 (IZ : OZ, 500 : 500), and T4 (LP + MFA [0.1% Essential oils + 0.08% Protease + 0.02% Xylanase]). The daily feed allowance was adjusted to 2.7 times the maintenance requirement for digestible energy (2.7 × 110 kcal of DE/kg BW^0.75). This allowance was divided into two equal parts, and the piglets were fed at 08 : 30 and 17 : 30 each day. Water was provided ad libitum through a drinking nipple. The diarrhea score was significantly increased (p < 0.05) in NC treatment compared with other treatments. The apparent total tract digestibility (ATTD) of dry matter (DM), nitrogen (N), and gross energy (GE) was significantly increased (p < 0.05) in the T2 treatment compared with the PC and NC treatments in week 1. In week 2, the ATTD of DM, N, and GE was significantly decreased (p < 0.05) in the NC treatment compared with other treatments. The T3 treatment had significantly higher (p < 0.05) ATTD and apparent ileal digestibility of zinc than the PC and T1 treatments. The Escherichia coli count in feces was significantly decreased in the T4 treatment compared with the NC and T2 treatments. The Lactobacillus count in feces was significantly increased in the T4 and T1 treatment compared with the T2 and T3 treatments. In conclusion, IZ : OZ 500 : 500 levels could improve nutrient digestibility and zinc utilization in weaned piglets, Moreover, MFA in LP diets could be used as a zinc alternative.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.2
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• pp.229-236
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• 2007

This study was conducted to determine effects of different selenium (Se) sources on performance, carcass characteristics, blood measures (whole blood Se concentration and plasma glutathione peroxidase (GSH-Px) activity), and Se concentrations in tissues of finishing Hanwoo steers (Korean native steers). Twenty finishing Hanwoo steers (average body weight=536${\pm}$23.4 kg, average age=approximately 20 months) were allotted to treatments in four groups of five steers per pen for 16 weeks preceding slaughter. Treatments were control (CON), spent mushroom composts from Se-enriched mushrooms (Se-SMC), selenized yeast (Se-Y), and sodium selenite (SS). Dietary Se levels of all treatments except CON were 0.9 mg Se/kg on the dry matter basis. Body weight was measured at the first and final day of trial, and blood samples were collected to analyze whole blood Se concentration and plasma GSH-Px activity at 2, 4, 8, and 16 weeks. At the end of trial, steers were slaughtered to collect muscle and liver samples for their Se analyses, and carcass data were recorded. In terms of dry matter intake, body weight gain and carcass characteristics, no significant differences among treatments were observed. Whole blood Se concentrations were significantly higher (p<0.05) for Se-SMC and Se-Y treatments than for CON at each collection period, with no significant difference between SS and CON. For weeks 2 and 8, there was no significant difference for whole blood Se concentration between Se-SMC and Se-Y, but for weeks 4 and 16, Se-Y treatments were significantly higher (p<0.05) than Se-SMC. No differences were observed for plasma GSH-Px activity between Se-SMC and Se-Y. The Se concentrations in hind leg and liver were significantly different among treatments (p<0.05) and those in both tissues ranked the greatest in Se-Y, followed by Se-SMC, SS, and CON treatments. However, tissue Se concentration for SS was not different from that for CON. These results showed that feeding organic Se sources such as Se-SMC and Se-Y enhanced Se concentration in tissues, while SS, the most common supplement of inorganic Se, was inefficient in Se deposition. Even though Se-Y had a higher Se concentration in tissues than Se-SMC, replacing Se-Y with Se-SMC in diets of beef steers would be an inexpensive way to increase Se concentration in beef.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.4
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• pp.334-340
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• 1997

It was proven that rice straw can serve can serve as a good support medium for trickling filter with livestock wastewater treatment. The efficiency of removal of removal of environmentally undesirable components from the wastewater by the straw medium was no less inferior to other commonly used support materials. The treated straw was also proven to be a source of abundant plant nutrients. The growth of orchard grass was enhanced greatly by the application of large quantity of the support medium. A maximum yield of dry matter was obtained at the rate of 40 ton/ha. Inorganic NPK elements as background fertilizers were highly recommended for better development in an early stage of growth. The nutritional status of the soil was very much improved by the addition of the medium in terms of exchangeable cations(K, Ca, Mg and Na), available phosphate, and organic matter contents. Nutrient uptake by orchard grass such as N, P and cations was enhanced by rice straw medium treatment and that was proportional to the levels of treatment.

• Asian Journal of Atmospheric Environment
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• v.6 no.3
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• pp.234-243
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• 2012

The wintertime high loading for atmospheric pollutants is certainly expected in the Byunsan Peninsula of Korea because of a great-scale reclamation project having construction of 33 km tidal sea dike impounding an area of over 40,000 ha and long-range transport. The goal of this study is to trace the origin of this wintertime burden for ambient particulate matter (hereafter called "PM") in the Byunsan Peninsula of Korea. The size-segregated (i.e., cutoff size from 0.01 ${\mu}m$ to 4.7 ${\mu}m$) PM sampling was conducted at a ground-based site of Byunsan Peninsula located in the west coast of Korean Peninsula during the height of dike constructing. Data archived in this study are the mass concentrations of ionic, elemental, and carbonic components in size-fractioned PM. The elemental mass of individual submicrometer particles was also analyzed. The sum of 5-source (i.e., elemental carbon, organic materials, inorganic secondary pollutants, crustal matter, and sea-salts) concentrations shows the bimodal distribution (major and minor peaks formed around $D_p$, 0.65 ${\mu}m$ and $D_p$, 4.7 ${\mu}m$, respectively) by border with 0.19 ${\mu}m$ of cutoff size. The concentrations of EC in $PM_{1.1-0.01}$ in winter and spring times were 4.62 ${\mu}g\;m^{-3}$ and 3.74 ${\mu}g\;m^{-3}$, respectively. Elemental masses of submicron individual particles are classified into two groups, i.e., the major elements (Cl, Al, Si, S, and P) and the minor trace elements. Cluster analysis differentiated the elements in submicron individual particles into 4-cluster. Among them, three clusters are in agreement with the major (Al, Si, S, and P), minor (Fe, Ca, and K), and trace compositions of coal burning. Meanwhile, Cl classified as an independent cluster has different source profile which was mainly due to the Saemangeum seawall project. Some highly toxic elements (e.g., Cr, Mn, and As (and/or Pb)) were also detected in some part of submicron individual PM. As a consequence, the combination of the Saemangeum project and winter monsoon played a considerable part in the double aggravation of wintertime air pollution in the Byunsan Peninsular.

• Journal of fish pathology
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• v.25 no.1
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• pp.39-46
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• 2012

Experiments were carried out to determine the hematological changes in freshwater tilapia Oreochromis niloticus, after water temperature (20, 25 and $30^{\circ}C$) and arsenic concentrations (200, and 400 ppb) exposure 20 days. The RBC count and hematocrit (Ht) were significantly increased in As 400 ppb and water temperature $30^{\circ}C$. Hemoglobin (Hb) was significantly increased under combined As (200 and 400 ppb) and water temperature $30^{\circ}C$. The tilapia exposed to water temperature $30^{\circ}C$ and As concentration 400 ppb increase significantly in calcium concentration. The high concentrations of total protein and glucose concentrations were observed at water temperature $30^{\circ}C$ and As concentration 400 ppb. A significant increment GOT and GPT activities in the tilapia serum noticed at water temperature (25 and $30^{\circ}C$) and As concentration (200, 400 ppb). These results indicate that tilapia can be affected by high water temperature ($30^{\circ}C$) and As concentration (400 ppb) in terms of inorganic matter, organic matter and enzyme activity in serum.