• Korean Journal of Ecology and Environment
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• v.39 no.2 s.116
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• pp.271-283
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• 2006

A systematic water quality survey was conducted in August, 2005 for a drinking water supply reservoir (the Jeolgol reseuoir located in an island), which is at an early stage of impoundment, to investigate the causes of water color deterioration of the reservoir and the clogging of filter beds of a water treatment plant. The reservoir shape was simple and its average depth was 5.5 m, increasing from upreservoir toward the downreservoir end near the dam. Dissolved oxygen (DO) and chloropllyll-a (chi-a) showed a large variation while water temperature had a smaller range. Transparency ranged from 0.6 to 0.9 m (average 0.7 m). The average value of turbidity was 9.3 NTU, ranging from 8.0 ${\sim}$ 12.1 NTU. The transparency and the turbidity appear to be affected by a combination of biological and non-biological factors. The poor transparency was explained by an increase of inorganic colloids and algal bloom in the reservoir. The blockage of the filter bed was attributed to the oversupply of phytoplanktons from the reservoir. The range and the average concentration of chi-a within the reservoir were 31.6 ${\sim}$ 258.9 ${\mu}g\;L^{-1}$, 123.6 ${\mu}g\;L^{-1}$ for the upper layer, and 17.0 ${\sim}$ 37.4 ${\mu}g\;L^{-1}$, 26.5 ${\mu}g\;L^{-1}$ for the bottom layer, respectively. A predominant species contributing the algal bloom was Dinophyceae, Peridinium bipes f. occultatum. The distribution of Peridinium spp. was correlated with chi-a concentrations. The standing crop of phytoplankton was highest in the upreservoir with $8.5\;{\times}\;103\;cells\;mL^{-1}$ and it decreased toward the downresevoir. Synedra of Bacillariophyceae and Microcystis aeruginosa of Cyanophyceae appeared to contribute to the algal bloom, although they are not dominated. It is mostly likely that sloped farmlands located in the watershed of the reservoir caused water quality problems because they may contain a significant amount of the nutrients originated from fertilizers. In addition, the aerators installed in the reservoir and a shortage of the inflowing water may be related to the poor water quality. A long-term monitoring and an integrated management plan for the water quality of the watersheds and the reservoir may be required to improve the water quality of the reservoir.

• Journal of Aquaculture
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• v.11 no.4
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• pp.573-580
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• 1998

Red spotted grouper, Epinephelus akaara is distributed in the south and west coasts of Korea. The natural stocks of the fish are decreasing sharply year by uear because of reckless overfishing. This research was carried out to understand general informations on maturation, sex composition and sex-reversals of the fish. Annual fishing uields of red spotted grouper in the castal area of Byonsan Peninsular of Kora decreased over 10% from 1992 to 1994. The main fishing season was from May to July with fishing gear of Hand-lines. Gonadosomatic index (GSI) and condition factor were highest on early and late July, respectively, thus main spawning reriod was assumed from late July to early August. The relationship between total length (X) and body weight (Y) for wild adults was represented as a regression, Y=$0.0169X^{2.9705}$, ($r^2$=0.96). Frequency of sex of wild red spotted gouper showed that the number of female below 38cm in total length was more than that of male, and hermaphrodite mainly occurred from 28cm to 32cm in total length the frequency of male and female were almost same. Also hermaphrodite occurred mainly between 25~29cm. Sex reversal ration of the adults reared in a tank for a year with different sexual compositions revealted that the frequency of female reversed from male was more than that of male reversed from female at 1:1 and 1:2 stocking densities of female and male, respectively. Also, about 20% of female was reversed to male when all females were reared. And the size of the fish reversed to male was larger than that of non-reversed female.

• Journal of Aquaculture
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• v.14 no.3
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• pp.181-195
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• 2001

To stabilize the lantern cage culture system of Patinopecten yessoensis(Jay) in the eastern coast of Korean peninsula, optimum conditions such as time of transplantation, rearing density and depth, and time of harvest were identified. During the period from January 1991 to December 1998, the water temperature ranged from 4.7 to 21.4$^{\circ}C$ at 15-30 m depth and 4.9 to 25.7$^{\circ}C$ at the surface; these thermal ranges were within the optimal ranges (5-23$^{\circ}C$) prevailing at 15-30 m depth at surface water. Annual thermal changes indicated that the prevailing temperature during the years 1993 and 1996 was near optimum, but higher during the years 1994, 1997 and 1998, when mass mortality and growth retardation occurred. Salinity (32.0- 34.4$\textperthousand$) and dissolved oxygen (4.14 -8.11 $\mu\textrm{g}$/l) at 15 m depth were well within the optimum ranges. The chlorophyll concentrations (0.06 - 2.73$\mu\textrm{g}$/l) indicated that the study area was oligotrophic, although mass mortality did occur, when chlorophyll concentrations were high, especially in summer. Hence water temperatures and chlorophyll concentration are major factors related to survival and growth of the scallop. In terms of the shell height maximum growth occurred during spring (March-May; 8 - l3$^{\circ}C$) and fall (October-December; 11-l7$^{\circ}C$) in the lantern cage culture. Slow growth was recorded during late winter January-february; less than 7$^{\circ}C$) and mid-summer (August- September; more than 18$^{\circ}C$). Daily growth of shell height and total weight were 0.02∼0.24 mm and -0.07∼0.90 g at the rearing density of 12 individuals per net. Optimal .earing density in the lantern cage (ø50${\times}$20 cm) was 10∼15 individuals with the shell height of 5∼6 cm. The fastest growth rates were observed at 15∼20 m depth; however, it is recommended that 20∼30 m would be optimal. The scallops require 22 months to attain the commercial size of 10 cm shell height and 140 g total weigh, and are best harvested and sold during March-April.

• Geophysics and Geophysical Exploration
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• v.1 no.2
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• pp.101-109
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• 1998

Using airborne magnetic data, magnetic characteristics were studied at the Samryangjin caldera area developed in the volcanics of the Yuchon sub-basin, the south eastern part of the Gyeongsang basin. Residual magnetics, reduction to the pole, horizontal derivative, and vertical derivative maps are prepared. Using these maps, the magnetic lithofaces are zoned and the geological structures such as caldera and faults were qualitatively interpreted. In addition, the two quantitative interpretations were performed. Firstly, the forward modelling were done to the 14.5 line km crossing the caldera area to the northeast-southwest direction. Applying the 3-D Euler deconvolution method to the whole study area, the depth extent and the characteristics of the magnetic anomalous bodies were studied. According to the results, the magnetic lithofaces of the area are zoned by 4 units. In general, these are well matched with the geological distributions. But the biotite granites intruded in the northern boundary of the Samryangjin caldera show the high magnetic intensity, while the biotite granites of the other areas show the low magnetic intensity and the different magnetic lithofaces. Thus, we interpreted that the biotite granites are closely related with the volcanic activity of the Samryngjin caldera, and are intruded in the fracture zones developed along the caldera rim. The Samryangjin caldera and fault structures of the area can be easily recognized by the distinct magnetic structures from the various magnetic anomaly maps. Also the topographic characteristics well reflect these structures. The results of the forward modelling show that the magnetic basement depth of the Gyeongsang sedimentary basin is on the average about 6 km and in maximum 10 km. And the depth becomes shallower toward the caldera boundary due to the shallow intrusion of the volcanics. The results of the 3-D Euler method also show the caldera and fault structures. And the relatively shallow magnetic anomalous bodies which are related with the volcanics are generally developed to the east-west and northeast directions, while the deep magnetic anomalous bodies to the northwest direction.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.9 no.3
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• pp.155-162
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• 1976

Forty one samples from thirty three species of algae (19 from 15 species of Rhodophyceae, 18 from 14 species of Phaeophyceae, 3 from 3 species of Chlorophyceae, and 1 of marine Phanerogams) collected from several locations on the east, west and south coast of Korea, were analyzed for their contents of crude protein, fat, cellulose, ash, nitrogen free extract, amino nitrogen, and total amino acids. For the examination of extractability of algal protein with water, 4 species of algae, Sargassum thunberggi, Grateloupia filicina, Phyllospadix japonica, and Sargassum confusum, were analyzed. And the effect of some precipitation treatments for isolation of algal protein was also tested. As a matter of fact, Rhodophyceae showed high content in crude protein and low in crude fat while the case was opposite for Phaeophyceae and Chlorophyceae. Refering to the content of crude protein and total amino acids, the recommendable algae for protein sources were Sargassum thunbergii, Acrosorium flabellata, Phacelocarpus japonicus, Laurencia okamurai, Laurencia intermedia, Grateloupia filicina, Chondrus ocellatus, Gloiopeltis furcata, Gigartina tenella, Dictyota dichotoma, and Scytosiphon lomentaria. Methanol treatment appeared most effective in precipitation isolation of protein from water extracts whereas pH control method did not so beneficial. The precipitation rate of protein was particularity higher in the extract of Sargassum confusum ana the lowest was makted from the extract of Sargassum thunbergii.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.33 no.3
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• pp.16-37
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• 2015

As a result of analyzing the forming and the transformations of Seokjojeon Hall garden by linking it to the changes of Deoksugung Palace influenced by the social atmosphere, the Seokjojeon garden can be classified into four phases. The first phase starts from 1896 to 1914. Gyeongungung was built in the late 19th century(1896-1897) as an official palace and Junghwajeon Hall and Seokjojeon Hall was built for Gojong. J.M.Brown was in charge of the construction of Seokjojeon in the beginning but H.W.Davidson saw the end also set up the garden. In the process of forming the garden the incorporating of Dondeokjeon Hall and the demolishing of the west wing corridors of Junghwajeon Hall occurred. At this phase of the garden a statue of an eagle was put up in the garden but was soon taken down. The shape of the garden was quiet simple with a central axial pathway, a round assorted flower bed placed in front of Seokjojeon Hall. The second phase starts from 1915 to 1932 which lasted for 17 years. At the last years of the Great Han Empire the duties of Gungnaebu(宮內府) was transferred to Leewangjik(李王職) in 1911 and a research on the existing buildings was done by Jujeonkwa(主殿課) in 1915. According to the research drawings, the garden still maintained the axial pathway formed in the previous phase but the garden had an asymmetric form. The flower bed was formed in a round shape and an open-knot technique and boundary plantation was applied to the garden. The third phase starts from 1933 to 1937 and is the period when Seokjojeon Hall was made public. By the year of 1932 many buildings of Deoksugung Palace had been demolished in the preparation of the opening of Seokjojeon Hall as a permanent exhibition hall. The central axial pathway still remained in the new garden and added a pond with a turtle statue in the center. The fourth phase starts from 1938 until the liberation from Japan and is the period when Deoksugung Palace became a park. Yi Royal-Family Museum was built and linked to Seokjojeon Hall with a bridge and the garden transformed into a sunken garden. The garden adopted a fountain and a pagora. Despite the minor changes in the after years the garden still posses most of its form from the fourth phase. As we can see the current garden of Seokjojeon Hall is not the same as the initial garden and therefor the importance of this study lies in the fact that modifications to the statements regarding to Seokjojeon Hall garden should be made.

• Korean Journal of Ichthyology
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• v.18 no.1
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• pp.1-11
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• 2006

Genomic DNA isolated from two geographical populations of pond-smelt (Hypomesus nipponensis) was amplified for RAPD (randomly amplified polymorphic DNA) analysis. The populations were obtained from Chungju (CJ), in the inland area, and Dangjin (DJ), in the vicinity of the West Sea in Korea. Seven arbitrarily selected primers, OPB-06, OPB-10, OPB-13, OPB-17, OPC-09, OPC-17 and OPC-20, were used to generate the shared loci, polymorphic, and specific loci. Three hundred and eighty-three loci observed per primer were identified in the CJ population, and 287 were identified in the DJ population. Among them, 91 polymorphic loci or 23.8% were polymorphic in the CJ population, and 47 (16.4%) in the DJ population. The number of shared loci observed was 198 in the CJ population and 176 in the DJ population. Forty-four and 75 specific loci were detected in the CJ and DJ populations, respectively. Especially, 99 numbers of shared loci by the two populations, with an average of 14.1 per primer, were observed in the two pond-smelt populations. The average bandsharing value between the two geographical pond-smelt populations was $0.700{\pm}0.008$, ranging from 0.600 to 0.846. Compared separately, the bandsharing value of individuals within the CJ population was higher than that of the DJ population. The dendrogram obtained using the data from the seven primers indicated three genetic clusters: cluster 1, CJ 01, 02, 03, 04, 05, 06, 07, 08, 09, 10, and 11; cluster 2, DJ 01, 02, 03, 04, 05, 06, 07, 08, and 09; and cluster 3, DJ 10 and 11. The genetic distance between the two geographical populations ranged from 0.040 to 0.545. Thus, RAPD-PCR analysis revealed a significant genetic distance between the two pond-smelt populations.

• Korean Journal of Ichthyology
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• v.25 no.2
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• pp.90-105
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• 2013

This study was performed to find out stomach contents of cold water fish such as Manchurian trout (Brachymystax lenok tsinlingensis) and River salmon (Oncorhynchus masou masou) in the Odae mountain area. Field survey was carried out 3 times by each season from May to October 2012 along the Gyebang stream and the Yangyang-Namdae stream at north-west mountain slope and north-east mountain slope of the Odae mountain area respectively. The result of digestive track analysis showed that food species of Manchurian trout were total individuals of 645 including 5 orders, 23 families, 39 species of benthic macroinvertebrates and 11 taxa of terrestial insects. And each IRI (Index of Relative Importance, %) value of food species by Manchurian trout was terrestial insects 37.0%, Trichoptera 36.4%, Ephemeroptera 20.0%, Diptera 3.9%, Plecoptera 2.7%, and Gordea <0.1%. While the River salmon fed on 1,186 individuals covering 4 orders, 20 families, 33 species of benthic macroinvertebrates and 6 taxa of terrestial insects including arachnid. Also IRI values by River salmon were terrestial insects including arachnid 2.7%, Ephemeroptera 52.9%, Trichoptera 27.9%, Diptera 9.4%, and Plecoptera 7.0% respectively. With these results, we might say that both Manchurian trout and River salmon is carnivorous fish which display the feeding preference to terrestial insects and benthic macroinvertebrates. As a results we could find out that the two kinds of cold water fish preferred similar habitat types and liked same order of food species in same season, however the compositions of food species for Manchurian trout and River salmon were considerably different.

• The Korean Journal of Malacology
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• v.22 no.2
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• pp.157-165
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• 2006

The present study was conducted to confirm that a bivalve Ruditapes philippinarum can be used as a biomarker for the monitoring of the heavy metal pollution in the silt of the marine environment. The clams were collected from the silt of Cheonsu-bay, Buheung-ri, and Tan-island of the West Sea, Korea. To observe the normal structures of the target organs (hepatopancreas and gill), they were dissected out for the immunohistochemical study and the electron microscopy with TEM, SEM, and SEM-EDS. The immunohistochemical study showed that the interdiverticular connective tissues of the hepatopancreas, and the outer epithelium of the gill lamellae was strongly reacted to anti-metallothionein (MT), indicating the presence of MT, a metal-binding protein, involved in metal detoxifying process. According to the examinations under the TEM, the epithelial cells of the hepatopancreas of the clams collected from polluted area (Tan-island) showed certain changes such as swollen rER, swollen nuclear envelope and inclusion bodies in the nulcei. In the SEM-EDS analysis, tissue of the hepatopancreas showed relatively higher concentration of S, Zn, and Cd. These elements are supposed to be concerning with the MT-reaction in the hepatopancreas. Considering that the coastal bivalve R. philippinarum showed immediate subcellular responses to heavy metal pollution in the overall experiments conducted, this species might act as one of efficient biomarkers for the heavy metal contamination in the marine environment.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.28 no.4
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• pp.36-48
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• 2010

The objectives of this study are to research and analyze the positioning of Mt. Back Hwa(白華山) and the characteristics of its neighboring cultural scenery based on the Two Seated Buddah Temple, a small Buddhist temple of Taeul in Taean and to view both landscape geographic codes and religious attractions over Mt. Back Hwa by discussing its expression and meaning for the scenery scattered or nested over this districts. The panoramic view of west shows the character of Mt. Back Hwa as a magnanimity of Buddhist Goddess of Mercy which is viewed as a view point field no less than its location as a landscape target and its singularity as a rocky mountain. The ancient castle, signal beacon post and the small Buddhist temple of Taeul to be read importantly in the old map and SinjeungDongkukyeojiseungram(新增東國輿地勝覽) form the core of place identity, and a number of carve(engrave) letters such as Eopungdae(御風臺), Youngsadae(永思臺), etc. show the prospect of this mountain and monumentality derived from place characteristics. In addition removing of Taeiljeon, a portrait scroll of Dangun, national ancestor makes possible to guess the national status hold by Mt. Back Hwa in advance and to know that it has symbiotic relationship with indigenous religion and shares with the universal locality which have been continued for a long time through a portrait scroll of Dangun enshrined in Samsunggak. More than anything else, however the Rock-carved Buddha Triad in Taean, Giant Buddha of Baekjae era enshrined in the small Buddhist temple of Taeul is not only why Mt. Back Hwa, magnanimity of Buddhist Goddess of Mercy exists but also a signifier. In spite of such a placity, the union ideas of confucianism, buddhism and doctrinism of buddhism prevailed in the Late Joseon Dynasty allows the cultural phenomenon of taoism to be read in the same weight through Ilsogae(一笑溪) and Gammodae(感慕臺) which are mountain stream and pond area respectively centered in the carve letter, 'Taeeuldongcheon(太乙洞天)' constructed in front of the small Buddhist temple of Taeul, the Baduk board type of rock carvings engraved over them and a number of traces of carve letters made by confucian scholars since the Middle of Joseon Dynasty. The reason such various cultural sceneries are mixed in Mt. Back Hwa is in the results of inheritance of religious places and fusion of sprit of the times, and the various type of cultural scenery elements scattered in Mt. Back Hwa are deemed as unique geographic code to understand the multi-layered placity and the characteristics of scenery of Mt. Back Hwa in Taean.