• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.3
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• pp.82-88
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• 2005

This study was carried out to investigate on the change of NaCl content during the food waste composting and on the safety of food waste compost(FWC) manufactured by the non-stirrer sealed fermenter. Plant culture test with pepper crop was also performed to see the effect of FWC, which was produced by the G co. ltd., on the growth of peper and migration of NaCl in soil. The culture test was performed at the farmland in Chungnam National University. The results were as follows; the NaCl content was gradually accumulated during food waste composting process, probably through water evaporation. Sodium concentration was, however, remarkably decreased at the final stage due to the desalting effect by water which was concentrated on the ceil of the fermentor. The analysis of chemical properties and humidity parameters on the food waste compost revealed that the product is quite a good qualified one. More than 0.5 tons of FWC application on red pepper cultivation caused diminished effect on the yield and the accumulation of salts on soil.

• Journal of Korea Water Resources Association
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• v.50 no.6
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• pp.387-395
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• 2017

Sea level rise, accompanied by climate change, is expected to exacerbate seawater intrusion in the coastal groundwater system. As the salinity of saturated groundwater increases, salinity can increase even in the unsaturated soil above the groundwater surface, which may cause crop damage in the agricultural land. The other adverse impact of sea level rise is reduced unsaturated soil thicknesses. In this study, a composite model to assess impacts of sea level rise in coastal agricultural land is proposed. The composite model is based on the combined applications of a three dimensional model for simulating saltwater intrusion into the groundwater and a vertical one dimensional model for simulating unsaturated zone flow and transport. The water level and salinity distribution of groundwater are calculated using the three dimensional seawater intrusion model. At some uppermost nodes, where salinity are higher than the reference value, of the 3D mesh one dimensional unsaturated zone modeling is conducted along the soil layer between the ground water surface and the ground surface. A particular location is judged salinized when the concentration at the root-zone depth exceeds the tolerable salinity for ordinary crops. The developed model is applied to a hypothetical agricultural reclamation land. IPCC RCP 4.5 and 8.5 scenarios were used as sea level rise data. Results are presented for 2050 and 2100. As a result of the study, it is predicted that by 2100 in the climate change scenario RCP 8.5, there will be 7.8% increase in groundwater saltwater-intruded area, 6.0% increase of salinized soil area, and 1.6% in increase in water-logging area.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.9 no.4
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• pp.196-203
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• 2004

To understand the geochemical processes in the Han River Estuary, distributions and behaviors of nutrients, dissolved organic matters, and uranium were investigated and analyzed during estuarine tidal mixing in June 2000 and February 2001. The distribution of inorganic nutrients showed very dynamic distributional patterns implying an apparent nitrification process and a concave non-conservative mixing along the salinity gradient. Dissolved organic carbon was high in the upstream region and decreased sharply in the low salinity region of around 5 psu. The 3-D fluorescence characteristic of dissolved organic matter showed two distinct fluorophores in the study area. Biomacromolecules originated mainly from the indigenous biochemical processes and geomacromolecules from terrestrial humic materials. In the study area, the distribution of geomacromolecule showed a concave non-conservative property along the salinity gradient presumably due to the flocculation and removal processes in the estuary. Meanwhile, distribution of the dissolved uranium, mainly in the form of stable uranium carbonate complex, also showed a concave non-conservative property along the salinity gradient in the Han River Estuary. From this study, the removal rate of dissolved uranium in the Han River Estuary was estimated to be about 7.1 ton per year.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.33 no.4
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• pp.321-333
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• 1997

This paper describe on the transmitting/receiving functions and the monitoring effects for the telemetry system which is designed to monitor the environmental condition of a culturing fishery ground inside a bay. The telemetry experiments were carried out by the telemetry system which constructed with the sea water temperature/salinity measuring sensor and telesounder at culturing fishery ground located in the coast of Sangyang-Myon, Kyongsangnam-Do province from October, 1995 to May, 1996. The results of this experiment showed that the developed telemetry system could be used for monitoring the sea water temperature/salinity and the distribution of fish in culturing fishery ground.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.16 no.2
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• pp.70-80
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• 2011

Estuarine ecosystem responds sensitively to natural and anthropogenic perturbations. lt is necessary to identify the direction of the change when the perturbation occurs as well as to understand the structure and functioning of estuarine ecosystem for a proper management of the area. In this study, the estuarine habitats were classified into different ecological districts so as to the switch from one district to another district could be related to the environmental change due to the perturbations. Total 16 ecological districts was defined according to the presence of barrage, salinity and vegetation characteristics. The defined ecological districts were applied to small estuaries in Goseong bay, south sea of Korea (Baedun, Guman, Maam, Goseong) to distinguish different regions which might have characteristic bottom topography, inclinations of river bottom, sediment characteristics, salinity structure and area of vegetation. Total 7 out of 16 ecological district was identified in this region; NFB (natural, fresh, bare), NHB (natural, high salinity, bare), NLV (natural, low salinity, vegetated) in natural (without barrage) estuaries and CFB (closed, fresh, bare), CFV( closed, fresh vegetated), CLV (closed, low salinity, vegetated), CHB (closed, high salinity, bare) in closed (with barrage) estuary. A comparison of environmental factors and biota between CHB and CLV demonstrated the effect of barrage on estuarine ecosystem. The height and sediment characteristics of CHB and CLV were similar but the average salinity was lower in CLV than in CHB due to the barrage, which produced favorable condition for the Phragmites australis in CLV. Information regarding the ecological districts in various sizes and location could be useful for predicting the ecosystem change due to natural and anthropogenic perturbations and for preparing management actions.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2008.11a
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• pp.168-169
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• 2008

해양환경의 변화에 따른 식물플랑크톤의 변동 특성을 파악하고자 해양환경변화에 따른 먹이생물의 변화를 살펴보았다. 수온은 하계에 높고 동계에 낮았으며, 염분은 동계에 높고 하계에 낮은 계절변동을 보였다. 용존산소는 하계 내만에서 3 mg/L 이하의 빈산소 수괴가 나타났다. 식물플랑크톤 현존량은 춘계인 5월에 4,500 cells/L이상으로 가장 높았으나, 6월에 급격히 낮아졌다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.10a
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• pp.231-232
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• 2000

자치어의 소화생리에 대한 연구는 담수어인 잉어, 무지개송어 등과 해산어인 넙치, 혹돔 등의 연구가 있으나 자치어 단계에 서식지의 변화가 큰 어종에 대한 연구는 전무한 실정이다. 따라서, 본 연구는 담수생활의 자어기에서 해수생활의 치어기로 전환하는 황복의 초기단계에 소화효소의 변화과정을 밝히고, 온도ㆍ염분ㆍ빛 등의 환경요인과 소화효소와의 관계를 조사하고자 한다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.444-445
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• 2001

서해는 수심이 얕은 천해로 대기 및 담수유입의 영향을 많이 받아 온도, 염분, 영양염 등의 환경변화가 계절적으로 매우 큰 지역이다. 우리나라 서해 연안에 서식하는 많은 어류들은 적수온을 따라 이동하여 종조성 빛 양적 변동이 계절에 따라 크게 변화하는 것으로 보고되고 있다(Lee ＆ Seok, 1984; Lee, 1989; Lee ＆ Kim, 1992; Lee ＆ Hwang, 1995; Lee, 1996). (중략)

• Journal of the Korean earth science society
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• v.33 no.6
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• pp.554-566
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• 2012

High-density temperature and salinity profiles from the successful international Argo project made it possible to reproduce the three-dimensional global ocean state in near-real time, which also increased much attention on the data analysis studies of global ocean. This paper reviewed several important issues on the recent data analysis studies such as systematic biases of XBT (eXpendable BathyThermograph) and Argo data, sea level budget discrepancy between steric height and satellite observed data, heat content change, and the current status of the development of objective analysis fields. This study also emphasized that it is required to carry out very cautious ocean data quality control and understand global-scale ocean variability prior to analyzing the regional-scale ocean climate change, particularly, in the East Asian marginal Seas.

• Journal of Yeungnam Medical Science
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• v.1 no.1
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• pp.107-113
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• 1984

To evaluate the morphologic changes of the renal arteries in the condition of high-salt diet, we scheduled the control group which fed routine animal diet added 0.06% of Sodium chloride, low-salt group which fed with 2.0% of sodium chloride, and high-Salt group which fed with 8.0% of sodium chloride. The experimental animals were sacrificed every two week until 20 weeks of final experimental week. The results obtained were as follows; 1. Slight intimal thickening of the renal arteries is observed from 16th experimental week and continued the end of the experiment in the rats of control group. 2. In low-salt group slight intimal thickening of the renal arteries is observed from 12th experimental week and continued to the end of the experiment. 3. In high-salt group the intimal thickening began from 6th experimental week and its degree was hasten with week, and provoked moderate to high degree of lesion at the end of the experiment. Medial proliferation and degeneration of the intima and media, though their quality is mild, also associated at the end of the experiment.