• Korean Journal of Environmental Biology
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• v.27 no.4
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• pp.425-432
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• 2009

Mesozooplankton dynamics were studied in Watan stream which flows into the Yellow Sea in Yeonggwang, Korea. Samples were collected at eight stations bimonthly during April 2006~February 2007. Mesozooplankton community was consisted of 45 taxa (8 cladocerans and 29 cope-pods). The abundance varied between the highest one ($31{\sim}127,587\;indiv.m^{-3}$) in October, and the lowest ($12{\sim}233\;indiv.m^-3$) in December. Diversity index showed to be the highest value in July (0.671) and the lowest one in August (0.368). A euryhaline species, Acartia hongi was dominant in brackish water stations (the highest abundance at $13.4^{\circ}C$ and 14.1 psu). In freshwater stations of the upstream, two cladoceran species of Polyphemus pediculus and Moina weismani occurred in high abundance in August. Dominant taxa of copepod were clustered to two or three groups mainly due to the difference of salinity gradients. Spatial distribution of mesozooplankton revealed to be determined by salinity gradients which were affected by opening and closing of the artificial dam in Watan stream.

• Analytical Science and Technology
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• v.6 no.3
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• pp.329-334
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• 1993

The formation of Mo(VI)-alizarin red S chelate ion its extraction into an organic solvent by ion-pairing for the separarive determination of trace Mo(VI) in natural water was applied in seawater samples. Removed Fe(III) and Zn(II), and Cu(II) by precipitating with anthranilic acid at pH 4.0 and 2.0, seawater 100mL was sampled in 250mL separatory funnel. After Mo(VI)-ARS chelate ion was formed by adding 0.01M alizarin red S solution 1.0mL to the water sample of pH 4.6, 0.6% aliquat-336 chloroform solution 10mL was added and the solution was vigorously shaked for about 30 seconds to form the ion-pair between Mo(VI)-ARS and aliquat-336 perfectly. The solution was stood for about 30 minutes. And the organic phase was taken for the absorbance measurement of the ion-pair at 520nm. The content of Mo(VI) was obtained from the standard calibration curve. Several extraction conditions such as pH, adding amounts of alizarin red S and aliquat-336, and shaking and standing times were optimized and the interferences and release of concomitant ions was also studied. This procedure was applied to the analysis of Eastern and Yellow seawaters. It could be confirmed from the recoveries of over 85% in samples spiked with a given amount of Mo(VI) that this method was also quantitative in the determination of trace Mo(VI) in a seawater.

• Korean Journal of Ichthyology
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• v.5 no.2
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• pp.151-159
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• 1993

Greeling, Hexagrammos otakii Jordan et Starks is commonly found at the coastal waters of Korea and Japan. The authors carried out the artificial insemination in the laboratory on Dec, 17, 1987, and reared the hatched larvae in an aquarium. The eggs were demersal and adhesive, and their diameters were 2.00~2.15mm. Color of yolk was light yellow in the early stage, and then turned to orange before hatching. The yolk had numerous tiny oil globules. Hatching began about 477hours after insemination under water temperature of $10.0{\sim}14.5^{\circ}C$. The newly hatched larvae were elongate in shape and 7.48~8.25mm in total length(TL) with 49~50 myomeres. The larvae absorbed the yolk material and oil globules completely in 5days after hatching and became postlarvae. In 17days after hatching, mean total length of the larvae was 9.85mm, and the caudal notochord flex at $45^{\circ}$. In 23days, total length reached 10.54mm. The part of the fin-fold of the future dorsal and anal fins became high. Spawning season of the Greenling is known to be from November to January in the southern coast of Korea.

• Korean Journal of Microbiology
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• v.1 no.1
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• pp.38-44
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• 1963

According to the experiment on pure-isolation and the related contaminants of Chlorella, the phenomena of the ecological distributions of Chlorella in Korea have been manifested in several areas and also the aim that in going to do culture, biological and physiological study of Chlorella is carried out. Contaminants very oftenly occupied on the colony of the strains taken in order to fulfil pure-isolation of Chlorella, but in accordance with being piled up the minute research on this subject, I can obtain the desirable results as follows: 1. For the pure-isolation, the duration chose the time from May to September 1957 so that may easily isolate from contaminant water with utilizing the antibiotic substances. 2. To take long time, 36-48 hours until growth of nascent through the non-sporulated, it originates from the difference of the cultured media. In addition to the above mention, the mechanism of growth until nascent through the sporulated must not always require the ligh. However the supply of metabolic energy depend upon its nutritional conditions per phase. 3. The culture of Chlorella should be based on the lower culturing except adding especial conditions such as reagent concentration of media, artifical shake of media and other facts due to the natural conditions. And also these strains grew not only in distilled water but 2% NaCl solution without any abnormality in cell it self. I, therefore, guess it is possible to culture in sea-water under phasic environment. 4. In the experiment of ammonia detection, it is caused by the sampling surroundings to contain the minute quantity of ammonia in strain No. M 918; that is the place to be plenty of Carbohydrate on behalf of protein. 5. To compare the absorption curve of chlorophyll of higher plant with that of Chlorella, the absorption zone made mostly the Same ones each other but a little absorption grade dose not clearly appear. The colony which formed giant type grows with intensive colour and green band on surrounding of the colony and after that it was changed into all the green colour and developed up to end. 6. At first phase for a week, the development of Chlorella suspends the normal condition as in vivo but after a few days, the colour of chlorophyll gradually changed into blue-yellow which secrete the mucous substances on the agar media. The cell was flew out the contained substances itself on leaving the cell wall only, or the various micro-organism diffused on the outer-region of the cell.

• Journal of the Korean earth science society
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• v.21 no.1
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• pp.22-22
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• 2000

To search out the characteristics of the lower and the upper atmospheric vertical structure, we selected the island(Oeyoundori Ochun-myen Poryeng city Chung-Nam) as an observation site, which is thought to represent the characteristics of ocean well, and observed the vertical structure of the atmosphere by Radiosonde. By using the results of the observation, we analyzed the changes of relative humidity(RH), temperature and wind when the cyclone and the anticyclone passed and compared the results in case of each event. To compare the vertical structure of the ocean atmosphere with those of the continent, we analyzed the values observed with using Radiosonde at Osan site.Through this study, we found that relative humidity changed as the cyclone and the anticyclone passed. That is, when the cyclone came, RH increased first in the upper atmosphere than in the lower and when the high came, RH in the upper decreased sharply to 10%. And the variations of relative humidity in ocean are bigger than those in continent. In the future, we plan to find out the relation between the vapor water in ocean and continent seasonally and daily through the observation in ocean and continent at same time.

• Journal of the Korean earth science society
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• v.21 no.1
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• pp.23-39
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• 2000

To search out the characteristics of the lower and the upper atmospheric vertical structure, we selected the island(Oeyoundori Ochun-myen Poryeng city Chung-Nam) as an observation site, which is thought to represent the characteristics of ocean well, and observed the vertical structure of the atmosphere by Radiosonde. By using the results of the observation, we analyzed the changes of relative humidity(RH), temperature and wind when the cyclone and the anticyclone passed and compared the results in case of each event. To compare the vertical structure of the ocean atmosphere with those of the continent we analyzed the values observed with using Radiosonde at Osan site. Through this study, we found that relative humidity changed as the cyclone and the anticyclone passed. That is, when the cyclone came, RH increased first in the upper atmosphere than in the lower and when the high came, RH in the upper decreased sharply to 10%. And the variations of relative humidity in ocean are bigger than those in continent. In the future, we plan to f d out the relation between the vapor water in ocean and continent seasonally and daily through the observation in ocean and continent at same time.

• Journal of the Korean earth science society
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• v.31 no.6
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• pp.541-554
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• 2010

Fifteen min-microtremor data sets were collected at 136 sites from a coastal area of Kunsan and 117 sites from an inland area of Jeonju located in SW Korea, and were analyzed for the HVSR (Horizontal to Vertical Spectral Ratio) of the sites. The microtremor spectra of the coastal area have stronger energy in the lower frequency range from 1-6 Hz than those of the coastal area. This result can be attributed to the effect of the waves and tides in the Keum river and the Yellow sea. Twenty four hours of measurement of the microtremor indicated that the microtremor spectrum correlates with the human activities, but the microtremor HVSR peak was observed consistently at the characteristic frequency for the site. The HVSR peaks were grouped into 4 types -"single peak", "double peak", "broad peak" or "no peak"- based on their shapes. More than 90% of the data sets exhibit peak frequencies ($F_0$) which can be easily identified. The distribution of $F_0$ reveals a close relationship with the topography and local geology of the areas, exhibiting high F0s in the hillside areas and low $F_0s$ in the reclaimed land area. While the amplitudes of microtremor HVSR peak frequencies are less than 4 in the downstream of the inland area, those of the recently reclaimed land in the coastal area are extremely high (more than 10). The results of this study indicate that detailed HVSR studies are essential for the earthquake hazard reduction of reclaimed lands.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.3
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• pp.51-58
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• 2006

The purpose of this research presents a method to position and makes the structure for eco-corridors reasonably with collectable analysing results of various effects shown in mammals' road-kill at 429 points. Target animals of this research are Leopard cat, Siberian weasel, Raccoon dog, Korean hare, Eurasian red squirrel, Siberian chipmunk and Water deer. The results derived from the empirical analysis on the contents above are followed. First, according to the results as for Leopard cat road kill analysis, which is designated as Endangered Species Class II, the eco-corridor might be located at near village having stead food in order to decrease the frequencies of road-kill, because its road kill points were mainly collected at 4 lane hilly road with mountain-road-farm area geological type of. Second, because Siberian weasel's road kill was detected at 2 lane hilly road with mountain-road-stream geological type, the eco-corridor might be located at near a mill to decrease road-kill frequencies. Third, the road-kill frequency of Eurasian red squirrel can be reduced when the eco-corridor is located at the area across coniferous tree near 4 lane west sea freeway with mountain-road-mountain. Fourth, the road-kill of Raccoon dog can be reduced when the eco-corridor is located at 4 lane mountain road or hilly road with the geological type having farm land-road-mountain(stream). Fifth, Korean hare's road-kill can be reduced when the eco-corridor is located at grass land across ridge line of mountain, because wild rabbit road kill was happened at 4 lane mountain road or 2 lane mountain road(mountain-road-mountain). Sixth, As for Siberian chipmunk, the eco-corridor might be located at the side slope of mountain road at 2 lane mountain road under the speed of 60km/h with mountain-road-mountain. Seventh, For Water deer, the eco-corridor might be located at 4 lane hilly road with mountain-road-farm land. As for Common otter, Amur hedgehog, Yellow-throated marten, Weasel, it is difficult to specify the proper site of eco-corridor due to the lack of data. Eco-corridors for carnivores might be well located at 4 lane hilly road or 2 lane hilly road with mountain-road-farm land, and the track for herbivores might be well located as a overhead bridge on mountain-road-mountain type across mountains. In order to position eco-corridors for wildlife properly, we have to research animal's behavior with ecological background, and to consider the local uniqueness and regularly collect the empirical road-kill data in long term 3 to 5 year, which can be the foundation for the more suitable place of wild life eco-corridors.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.11
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• pp.2025-2036
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• 2000

A physicochemical process called ultra rapid coagulation(URC) was applied as a pilot scale to recover eutrophicated lake water at Inkyung Lake located on-campus in Inha university. The URC was uniquely designed to completely remove the presence of phosphorus up to 95%, which in turn leading to lessen the level of eutrophication of lake. For a pilot test of period, the lake was restored showing Carlson's Trophic State Index(TSI) of mesotrophic state which accounts for the reduction of total phosphorus and chlorophyll-a down to approximately 55 from 70 and 73, respectively. A residual presence of aluminum and additional coagulants in the effluent was tested for their potential effects on Photobacterium phosphoreum. The effect concentration ($EC_{50}$-15 min) observed in the effluent revealed that the bioactivity of Photobacterium phosphoreum was not influenced by the residual presence of coagulants. After the pilot test of period, the lake was consequently restored as a mesotrophic state in obtaining the second grade of lake water quality. The URC may be further applied for restoration of greater scale of lake in eutrophication.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.4
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• pp.377-384
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• 2005

Algae causes not only the eutrophication of lake, but also the deterioration of drinking water process. Especially, algogenic organic matters(AOM) are assumed as disinfection by-products(DBPs) precursors like humic and fulvic acids. In this study, it was investigated the characteristics changes of algogenic organic matter(AOM) by prechlorination and coagulation treatment. Evaluation of enhanced coagulation and applicability of UV oxidation process were also evaluated as the drinking water treatment system for the eutrophicated water source. prechlorination was effective process for algae removal but caused releasing of dissolved organic matter(DOC) into water due to the destruction of algae's cell. In coagulation treatment with Fe(III) coagulant, reaction pH is an important factor for the removal of AOM and triholomathanes(THMs). At pH 5, removal efficiency of DOC and THMs were dramatically improved by 50% and 28%, respectively, in comparison with the conventional coagulation treatment at about pH 7. Photo-Fenton($UV/H_2O_2/Fe^{3+}$) process among the UV oxidations is the most effective system to remove AOM, but its removal efficiency was lower than that of enhanced coagulation treatment at pH 5.