• Proceedings of the Plant Resources Society of Korea Conference
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• 2001.11b
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• pp.49-61
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• 2001

This study was carried out to determine the effect of various fertilizer levels, sowing time and planting density on the growth and yield of Scuteliaria baicalensis GEORGE cultivated after the barley in the southern coastal areas of Korea under the non- mulching condition by direct sowing culture. The flowering date of medium dressing plot(N : P$_2$O$\sub$5/ : K$_2$O=9 : 13.5 : 9kg/10a) and heavy dression plot(N : P$_2$O$\sub$5/, : K$_2$O=12 :18 : 12kg/10a) were July 23. The flowering date of the medium and the heavy dressing plot was delayed by 3days compared with that of non-fertilizing plot. The growth characteristics such as stem length, diameter of main stem, number of branch per plant, main root length, main root length, main root thickness and dry weight of stem leaves were more increased at medium dressing plot than that of other fertilizer levels, The root dry weight of in Scutellaria baicalensis GEORGE cultivated after barley was hlghest at the fertilizing plot of N : P$_2$O$\sub$5/ : K$_2$O=9 : 13.5 : 9kg/10a. The dried-root yield was 178kg in medium dressing plot, 167kg in standard dressing pot, and 126kg in non-dressing plot, The dried-root yield of medium dressing plot was 7% and 41 cie higher than that of standard dressing pot and non-dressing control plot, respectively. Emergence and flowering dates in the sowing time of June 1 were earlier than those of the other sowing times. In the sowing time of June 1, length and diameter of main stem, number of node per main stem, number of branch per plant and dry weight of stem leaves were greater than those of sowing times of June 10 and June 20. Yield components such as main stem length and diameter, main stem numbers, branches per plant, dry weight of stem leaves, main root length and thickness, number of large root and fine root per plant, and dry weight of root were the highest at the sewing time of June 1 as the yield of 71.3kg/10a. Optimum sowing time of Scuteilaria baicaiensis GEORGE cultivated after barley was June 1 in southern areas of Korea. Stem length was long in dense planting of 20${\times}$10cm and short in spacious planting of 30${\times}$10cm and 40${\times}$10cm by direct sowing cultivated after barley. Stem diameter was thick in spacious planting of 30${\times}$10cm and 40${\times}$10cm and was thin in dense planting of 20${\times}$10cm by direct sowing cultivated after barley. Length and dry weight of root per plant were decreased in dense planting of 20${\times}$10cm and were increased in spacious planting of 30${\times}$10cm and 40${\times}$10cm by direct sowing cultivated after barley. Yield of dry root was highest in optimum planting density(30${\times}$10cm 33 plants/㎡) by direct sowing cultivated after barley. The correlation coefficient between number of planting plant and stem length showed highly positive correlation. These characters of stem diameter, number of branches, main root length and yield of dry root mentioned above showed negative correlations with planting plants.

• Journal of the Korean Chemical Society
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• v.48 no.4
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• pp.394-398
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• 2004

From Sargassum thunbergii which is widely distributed in coastal area of Korea, three norisoprenoids, (+)-epiloliolide (1), (-)-loliolide (2), and apo-9'-fucoxanthinone (3) were isolated by using column chromatography and reverse-phase HPLC. Compound 1, 2 and 3 were for the first time isolated from the Brown Alga Sargassum thunbergii. Particularly, Compound 1 was for the first time isolated the marine organism although it was reported from the terrestrial plant. Their structures have been determined by extensive 2-D NMR experiments such as $^1H COSY, NOESY, HMQC$, and HMBC and by comparison with the reported data in the literature.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.1
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• pp.16-22
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• 2014

This study was conducted to determine the changes in soil chemical properties and the growth of seedling according to the different dredged soil improving methods at slope of Saemangeum sea dike. Undersea dredged soil was improved by five different methods. Seedlings of Ulmus davidiana var. japonica, Chionanthus retusa, Celtis sinensis, and Pinus thunbergii were planted after 9 month of experience site installation, then soil pH, NaCl concentration in soil, soil organic matter (SOM), and survival rate and height of seedling was measured. Initial soil pH was highest in the control plot but it decreased to the similar level with other soil improving plots after 35 months. There were no differences in NaCl concentration between the control and soil improving plots, and it showed decreasing tendency during the study period. In the control plot, initial SOM was lowest among that of other plots during the study period. The survival rate of 36 months after planting of P. thunbergii was highest among the species. The gap of the tree growth of P. thunbergii between the control plot and the soil improving plots was small, however, other species showed relatively higher tree height in the soil improving plots than the control plots. Creation forest with P. thunbergii might be a cost effective afforestation in coastal reclaimed land since it rarely needs additional improvement of dredged soil.

• Journal of the Korean Society for Marine Environment & Energy
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• v.1 no.1
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• pp.83-92
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• 1998

Heavy metals concentration in superficial sediment of effluent discharging area was rapidly increased by annual loadings of Zn(8.465 Kg), Ni(3,291 Kg), Cu(1,636 Kg) and Pb(1,250 Kg) from sewage effluent of 63×10/sup 6/ m³/yr. In a consequent result, specially the concentrations of Zn and Cu in the sediment were three times higher than preindustrial reference values. The evaluation by multiple ecological risk indices showed that heavy metals contamination in sediment of discharging area was 'heavily Polluted level' by sediment quality criteria and increased 2.6 times by the degree of contamination. It was also judged that toxicological effects of sediment receiving the primary effluent would occasionally (16～47%) occur by guidelines for adverse biological effect.

• Journal of Microbiology and Biotechnology
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• v.12 no.6
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• pp.865-871
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• 2002

A bacterium having strong chitinolytic activity on $0.2\%$ colloidal chitin-containing agar medium was isolated from coastal soil in Korea. Based on the nucleotide sequence of conserved segment of a 165 rRNA gene, the bacterium was identified as Paenibacillus illinoisensis KJA-424. The population of P. illinoisensis KJA-424 and chitinase activity significantly increased for the first 2 days of incubation. On SDS-PACE analysis with $0.01\%$ glycol chitin, three protein bands (63, 54, and 38 kDa) with chitinolytic activity were detected tooted. The effect of P illinoisensis KJA-424 on the egg hatch of root-knot nematode (Meloidogyne incognita) was investigated. After 7 days of incubation with the chitinase-producing P. illinoisensis KJA-424, none of the eggs hatched, whereas a $39.8\%$ egg hatching rate was observed in the water control. Inverted and scanning electron microscopic observations demonstrated that P. illinoisensis KJA-424 deformed and destroyed the eggshell of M. incognita. In conclusion, chitinase-produced by p. illinoisensis KJA-424 caused the lysis of M. incognita eggshell and resulted in the inhibition of egg hatching in vitro.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.930-940
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• 2013

We evaluated contamination with organic matter and trace metals by analyzing grain size, ignition loss (IL), chemical oxygen demand (COD), acid volatile sulfide (AVS), and trace metals (Al, Fe, Cu, Pb, Zn, Cd, Ni, Cr, Mn, Hg, and As) in surface sediments at 28 stations around the Geum River estuary in July 2008. The surface sediments in the estuary were mainly composed of coarse sediment (sand and muddy sand), with mean grain size (Mz) ranging between $2-4{\O}$. The high concentrations of IL, COD, and trace metals were mainly found at stations in front of the Gusan outer port and industrial complex, and near the Seocheon coast with relatively fine sediments. In addition, the concentrations of IL and all trace metals, except Pb and As, showed good positive correlations with Mz, indicating that the concentrations of organic matter and trace metals were mainly dependent on sediment grain size. The concentrations of COD, AVS, and trace metals in most sediments did not exceed the sediment quality guideline (SQGs). Although the sediments in the study region are not polluted with organic matter and trace metals, there are many point sources of pollutants, such as Gusan port and industrial complex, Janghang refinery, and a thermoelectric power plant around the Geum River estuary. Thus, the management of coastal environments through periodic monitoring of organic matter and trace metals is required in the future.

• Journal of Korean Society of Water and Wastewater
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• v.31 no.6
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• pp.599-609
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• 2017

Desalination plants have been recently constructed in many parts of the world due to water scarcity caused by population growth, industrialization and climate change. Most seawater desalination plants are designed with a submarine pipeline for intake and discharge. Submarine pipelines are installed directly on the bottom of the water body if the bottom is sandy and flat. Intake is located on a low-energy shoreline with minimal exposure to beach erosion, heavy storms, typhoons, tsunamis, or strong underwater currents. Typically, HDPE (High Density Polyethylene) pipes are used in such a configuration. Submarine pipelines cause many problems when they are not properly designed; HDPE pipelines can be floated or exposed to strong currents and wind or tidal action. This study examines the optimal design method for the trench depth of pipeline, analysis of on-bottom stability and dilution of the concentrate based on the desalination plant conducted at the Pacific coast of Peru, Chilca. As a result of this study, the submarine pipeline should be trenched at least below 1.8 m. The same direction of pipeline with the main wind is a key factor to achieve economic stability. The concentrate should be discharged as much as high position to yield high dilution rate.

• Animal Systematics, Evolution and Diversity
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• v.27 no.1
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• pp.1-17
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• 2011

Thais Roding, 1798, commonly known as rock-shell, is among the most frequently found gastropod genera worldwide on intertidal rocky shores including those of Japan, China, Taiwan and Korea. This group contains important species in many marine environmental studies but species-level taxonomy of the group is quite complicated due to the morphological variations in shell characters. This study examined the genetic variations and relationships among three Korean Thais species based on the partial nucleotide sequences of mitochondrial cox1 gene fragments. Phylogenetic trees from different analytic methods (maximum parsimony, neighbor-joining, and maximum likelihood) showed that T. bronni and T. luteostoma are closely related, indicating the most recent common ancestry. The low sequence divergence found between T. luteostoma and T. bronni, ranging from 1.53% to 3.19%, also corroborates this idea. Further molecular survey using different molecular marker is required to fully understand a detailed picture of the origin for their low level of interspecific sequence divergence. Sequence comparisons among conspecific individuals revealed extensive sequence variations within the three species with maximum values of 2.43% in T. clavigera and 1.37% in both T. bronni and T. luteostoma. In addition, there is an unexpectedly high level of mitochondrial genotypic diversity within each of the three Korean Thais species. The high genetic diversity revealed in Korean Thais species is likely to reflect genetic diversity introduced from potential source populations with diverse geographic origins, such as Taiwan, Hong Kong, and a variety of different coastal regions in South China and Japan. Additional sequence analysis with comprehensive taxon sampling from unstudied potential source populations will be also needed to address the origin and key factors for the high level of genetic diversity discovered within the three Korean Thais species studied.

• Journal of the Korean Geotechnical Society
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• v.30 no.12
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• pp.63-72
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• 2014

To observe the behavior of lateral deformation of buried pipe and the preventing effect of embankment piles against the lateral deformation, a series of full-scale field tests were performed on a reclaimed coastal area. A buried pipe was installed in the west coast undergoing reclamation and embankment was performed by three steps. Then vertical settlement and lateral displacement were measured by the settlement plate and the inclinometer. Embankment pile system were applied to prevent the lateral displacement of buried pipe. Heave of the buried pipe slightly happens during embankment and following settlement. Finally the behavior steadily converged. The preventing effect of the embankment pile was approximately two times stronger than non-reinforcement. Both settlement and lateral displacement appear to be bigger at upper ground and smaller at lower ground.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.5
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• pp.460-464
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• 2012

From 1998 to 2008, the bacteriological quality of seawater in Kamak Bay, Korea, was monitored. The total and fecal coliforms in seawater were monitored as bacterial indicators, and the level of fecal coliform contamination was used to evaluate seawater quality. In the southern shellfish growing area of Kamak Bay, the observed fecal coliform geometric mean (GM) and estimated 90th percentile did not exceed the quality standards for fecal coliforms in seawater in Korea and th USA (GM<14 MPN/100 mL, 90th percentile<43 MPN/100 mL). The GM and estimated 90th percentile of the fecal coliform levels in the adjacent northern area of Kamak Bay were higher than in the southern area. Stations near wastewater discharge sites and urban areas in the north had the lowest quality and did not meet the bacteriological seawater quality criteria. The high fecal coliform levels in the Seonso coastal region near wastewater discharges and northern urban areas declined significantly following dredging and operation of a sewage treatment plant.