• Title, Summary, Keyword: 남조류

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Depositional Environments and Characteristics of Surface Sediments in the Nearshore and Offshore off the Mid-Western Coast of the Korean Peninsula (한반도 중서부 근 ${\cdot}$ 외해의 표층 퇴적물 특성과 퇴적환경)

  • Oh, Jae-Kyung;Kum, Byung-Chul
    • Journal of the Korean earth science society
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    • v.22 no.5
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    • pp.377-387
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    • 2001
  • In order to elucidate sedimentation processes and depositional environments in transitional area between continental shelf and coastal zone, sedimentologic study has been done with 84 surface sediments sampled in nearshore/offshore off the mid-western coast of the Korean Peninsula for 3 years (1996${\sim}$1999). The surface sediment can be classified into 4 facies (gravelly sand, sand, silty sand and sandy silt). Mean grain size, sorting, skewenss and kurtosis varies -0.39${\sim}7.82{\Phi}$, 0.36${\sim}4.68{\Phi}$, -0.38${\sim}$0.86, -1.56${\sim}$3.43, respectively. The textural parameters show a finer-grained and poorly-sorted trend shoreward, northward and southward from the central part of the study area. The positively-skewed distribution and relationship of each textural parameters indicate a tide-dominated depositional environment. According to C/M diagram, there are 3 different domains (mode A, B, C) of sediment transport mode. The northern part is characterized by bedload transport (mode A) and represents co-influence of wave and tide, whereas domain C in the southern part is controlled by uniform suspension transport (mode C), correlating with sandy-silt area. In the broad middle area, transport processes are complex (the mixture of bedload, graded suspension and uniform suspension; mode B). Hence, the subdivision depositional environments of this study area may be classified by 3 depositional environments dependent on the interplay of sediment supplies from river, relict sediments and hydrologic conditions. In results, the nearshore and offshore areas are thus characterized as a mixing zone between coastal terrigenous sediments and relict sediments in the continental shelf by complex processes (tide, wave and river flow). These sedimentation processes play an important role in producing distinct sedimentologic features in the transitional zone linking coastal and shelfal areas.

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Wetland Function Evaluation and Expert Assessment of Organic Rice-Fish Mixed Farming System (유기농 벼-담수어 복합영농의 습지기능평가 및 전문가 조사)

  • Nam, Hongsik;Park, Kwanglai;An, Nanhee;Lee, Sangmin;Cho, Junglai;Kim, Bongrae;Lim, Jongahk;Lee, Changwon;Choi, Seonu;Kim, Changhyun;Kong, Minjae;Son, Jinkwan
    • Journal of Wetlands Research
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    • v.20 no.2
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    • pp.161-172
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    • 2018
  • A mixed farming system that includes organic rice production and freshwater fish farming is being called into attention in Korean agricultural industry and rural areas in order to improve farm management and environmental conservation. This study was conducted to evaluate the environmental and ecological value of such mixed farming practices. Expert assessment and rapid assessment method (RAM) of wetland evaluation were employed for this study. Experts have responded that biodiversity conservation including amphibian and reptile habitat (2.39), aquatic insect habitat (2.36), Fishery habitat (2.34), vegetation diversity (2.13), avian habitat (2.05), and experience and education were the most important function of mixed farming. The wetland function evaluation conducted using modified RAM indicated that rice-fish mixed system showed improvements in most of the evaluated functions, compared to the conventional rice paddies. The overall wetland function of rice paddies in rice-fish mixed system was greatly improved as compared with the conventional rice paddies. Rice paddies are known to play an important role in biodiversity maintenance, and provide ecosystem services such as climate modulation and carbon reduction. Rice-fish mixed system of farming may not only improve various ecosystem services of rice paddies, but may increase farm income through value added fish farming, as well as promotion of social services such as education and maintenance of tradition. Additional research is needed for quantitative analysis of the values gained from the most improved wetland function when mixed farming system is actually put into practice, and to utilize the results in advertising of the organic rice, and in various sectors such as food, education and direct payment policy.

Microbial structures and their distributions in cave tufa formations from a twilight zone of the Baeg-nyong Cave (백룡동굴 입구부 튜파(tufa)의 미생물 구조와 그 분포 특성)

  • Jung, Da-Yea;Jo, Kyoung-Nam;Lee, Jung-Shin;Park, Shinae
    • Journal of the Geological Society of Korea
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    • v.53 no.5
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    • pp.743-758
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    • 2017
  • Microbial mats which formed at various terrestrial environments including the Earth's critical zone have a significant implication on the relationship between microbial activities and formations (and/or degradations) of minerals. Up to date, however, there is no geological survey for the microbial mats of tufa deposits in a twilight zone of Korean limestone caves. In this study, we aimed to report a variety of microbial structures and their distributions on tufa deposits in the Baeg-nyong Cave (Natural monument no. 260), Pyeongchang, South Korea. The sedimentary petrographic results for 7 tufa specimens collected near the cave entrance show that both of clotted and filamentous textures are largely dominant and their detailed types are different from each other. These characteristics of the tufa deposits are clearly different from those of the typical meteoric speleothems composed mainly of clean carbonate crystals and may indicate the past presence of microbial mats on the surface. Through the scanning electron microscopy, we have identified the various shapes of microbial structures including diatoms, hyphal filaments and coccoids. The microbial structures observed in this study have been classified to 2 and 7 types of coccoids and filaments, respectively, based on shape, size and arrangements between individual structures. Interestingly, our results show that the diversity of microbial structures in the Baeg-nyong Cave is gradually increasing to the inner cave with a distinct threshold area which is abruptly decreased in the microbial structural diversity. This may imply that an entrance area of the limestone cave is one of the microbe growth stimulating environments and has been affected by complex factors on geological, geographical and micro-meteorological conditions.

Habitat Characteristics of Benthic Macroinvertebrates at a Headwater Stream in the Yeonyeopsan (Mt.) (연엽산 산지계류에 있어서 저서성 대형무척추동물의 서식특성)

  • Jang, Su-Jin;Nam, Sooyoun;Kim, Suk-Woo;Koo, Hyo-Bin;Kim, Ji-Hyeon;Lee, Youn-Tae;Chun, Kun-Woo
    • Korean Journal of Environment and Ecology
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    • v.34 no.4
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    • pp.334-344
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    • 2020
  • A total of 24 families, 44 species, and 658 benthic macroinvertebrates were identified, and Ecdyonurus dracon Kluge (13%) was the dominant species in forested streams within the Yeonyeopsan (Mt.). A total of four habit categories (i.e., clingers (56%), burrowers (19%), swimmers (14%), and sprawlers (56%)) were identified, and clingers were the dominant habit at all survey points except point one (UP1). Habitat characteristics were depended on the hydraulic factors (e.g., flow velocity, depth, and substrates), water quality (e.g., DO and water temperature), and the habitat characteristics were differed in the riffle, which has a faster the flow velocity, compared by in the stagnant pool. In other words, in riffles, the clingers dominated in high flow velocity with the large maximum and median grain size for substrates in the habitats regardless of depth, but the burrowers and sprawlers were dominant in low flow velocity with the small maximum and median grain size for substrates in the habitats. Moreover, DO and flow velocity were in positive correlation (y = 0.6666x - 0.659, R2 = 0.0851), and the habitat for burrowers was wider than that for sprawlers or clingers. The water depth was negatively correlated with water temperature (y = -26.397x + 283.87, R2 = 0.1802) since the water temperature is more sensitive to insolation in shallow depth. pH was positively correlated with water temperature. The investigation of the habitat characteristics by separating the relations between pH and DO in upstream and downstream showed the low pH and high DO in the upstream with a high crown density of 68%, regardless of community composition. On the other hand, high pH and low DO in the downstream with a relatively low crown density of 51%. It was considered that the riparian forest played a role in suppressing the growth of attached algae and the controlling water temperature in headwater streams. Our findings identified the habitat characteristics of benthic macroinvertebrates in a headwater stream. We expected that the finding can provide reference data for suggesting conservation and management plans in a headwater stream and increasing academic value.

Effect of Freshwater Discharge from a Water Reservoir on the Flow Circulation in the Semi-Closed Harbor (유수지로부터의 담수 방류가 항 내 해수순환에 미치는 영향)

  • Choi, Jae Yoon;Kim, Jong Wook;Lee, Hye Min;Yoon, Byung Il;Woo, Seung-Buhm
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.33 no.1
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    • pp.1-12
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    • 2021
  • To investigate the effect of freshwater discharge on the seawater circulation in the semi-closed harbor, a 3-D hydrodynamic model was applied to the International Ferry Terminal (IFT). The model run is conducted for 45 days (from May 15 to June 30, 2020), and the reproducibility of the model for time-spatial variability of current velocity and salinity was verified by comparison with model results and observation data. There are two sources of freshwater towards inside of the IFT: Han River and water reservoir located in the eastern part of IFT. In residual current velocity results, the two-layer circulation (the seaward flow near surface and the landward flow near bottom)derived from the horizontal salinity gradient in only considering the discharge from a Han River is more developed than that considering both the Han River and water reservoir. This suggests that the impact of freshwater from the reservoir is greater in the IFT areas than that from a Han River. Additionally, the two-layer circulation is stronger in the IFT located in southern part than Incheon South Port located in northern part. This process is formed by the interaction between tidal current propagating into the port and freshwater discharge from a water reservoir, and flow with a low salinity (near 0 psu) is delivered into the IFT. This low salinity distribution reinforces the horizontal stratification in front of the IFT, and maintains a two-layer circulation. Therefore, local sources of freshwater input are considered to estimate for mass transport process associated with the seawater circulation within the harbor and It is necessary to perform a numerical model according to the real-time freshwater flow rate discharged.

A Study of Eight Cases According to Hyeongsang Diagnosis Applying Sa-am Acupuncture Therapy (8증례를 통한 사암침법(舍巖鍼法)의 형상의학적(形象醫學的) 운용에 관한 고찰)

  • Choi, Jun-Young;Nam, Sang-Soo;Kim, Yong-Suk;Lee, Jae-Dong
    • Journal of Acupuncture Research
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    • v.29 no.1
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    • pp.139-150
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    • 2012
  • Objectives : The puropse of this study was to report the availability of Hyeongsang diagnosis compensating for visceral pattern identification in applying Sa-am acupuncture therapy. Methods : Eight cases was presented to substantiate the above. Results : According to the characteristic diagnostic method of Hyeongsang medicine by feature such as face, ears, eyes, nose and mouth shape, There are 8 pattern differentiations, including essence family, Qi family, spirit family, blood family, fish type, bird type, beast(running) type and crust(crustacea) type which are correlated with essence deficiency, heat harassing the heart spirit, Qi stagnation, blood stasis, kidney essence deficiency, intense heart fire, liver blood deficiency and lung Qi deficiency in the established visceral pattern identification, respectively. Eight patients was diagnosed by the above Hyeongsang 8 pattern differentiations, of whom Sinjeonggyeok(kidney reinforcing prescription) was applied to a patient with fish type and essence family to nourish kidney essence, and Giul prescription(Qi stagnation prescription) was given to a patient with Qi family for regulating Qi, and Sanghwa priscription(ministerial fire prescription) was delivered to a patient with Spirit family to clear the heart fire and tranquilize, and Sojangjeonggyeok(small intestine reinforcing prescription) was used for a patient with blood family to nourish blood and remove blood stasis, and Sinjeonggyeok(kidney reinforcing prescription), Simhangyeok(heart heat clearing prescription), Ganjeonggyeok(liver reinforcing prescription) and Pyejeonggyeok(lung reinforcing prescription) were utilized for fish type, bird type, beast(running) type and crust(crustacea) type respectively to reinforce the relevant visceral function. Conclusions : It was suggested that characteristic diagnostic method of Hyeongsang medicine should be helpful for enhancing the accuracy of the established visceral pattern identification, applying Sa-am acupuncture therapy more appropriately.

The Aspects of Change of Sijo (시조의 변이 양상)

  • Kang Myeoung-Hye
    • Sijohaknonchong
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    • v.24
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    • pp.5-46
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    • 2006
  • Korean verse has flexibly changed its form and contents according to the historical background of the times. This fact arouses reader sympathy because it has reflected ideas, historical aspects and realities of the times. However, korean verse has kept its own characteristics in some ways, allowing it to exist today. It holds its form as 3 verses of three by three or four meter and three letters of the last of three verses. It makes every different version which has specific aspects of each times in the same 'sijo' area. 'Sijo' in Korean poems, is the first form that has been changed from formal to private functionally. As a result of that common verses in the Goryeo to Joseon eras were going with the stream of the times. Verse was the plate for justice so that there was no double meaning, symbols, or technical sentences. It had to show the idea of Myungchundo Jwonginryun. The theme was commonly fitted within certain areas. such as blessings, fidelity, devotion, etc. Around the end of the Joseon era, there was activation of private verses - a form of sijo with no restrictions on the length of the first two verses. Some ideas had been changed because Sarimpa gained power, domestic conflict, and the introduction of practical science. These things had an effect on the form of Sijo. After all, it shows the ideas of collapsing feudalism, resistance of confucian ideas, equality of the sexes, and opposition to the group who rule the government. Thus Sasul Sijo seems to have the tendency of resistance to reality. It was a specialty of realism poetry It explained our life in detail and reflected real life by being an intermediary of realism. This met and represented the demand of a reader's expectations. After 1905, there was new form of sijo that is very different, in form and content, from the previous versions. It was even different in areas of what people accepted. They started to think sijo was not the form of lyrical verse that is once was. It became a 'record of reading'. The form changed to 'hung or huhung' that satirized the times and the ending of a word in the last verse. Although this form could deliver the tension in statement, it was too iu from the original form. Therefore, it didn't last long, and its position got smaller because of the free verse that had western influence and was emerging in the times. In the middle of 1920, there was a movement of Sijo revival. It was lead by Choinamsun. He wrote poems and Sijo which were effected by western ideas in his early works. Although he worked with that, he took the lead in the movement of Sijo revival. He published the collection of Sijo $\ulcorner$Baekpalbunnwoi$\lrcorner$ that has one major theme-patriotic sentiment. He thought an ancient poem was a part of racial characteristics so that he expressed the main theme which represented the times and situations of his era. Modern Sijo is difficult. Sijo has to have modern and Korean verse characteristics at the same time. If it considers a modern aspect too much, it could not be distinguished from sijo and free verse. If it overly leans toward Sijo. it would seem to be too conservative which it then could be said to have no real charm of a poem. In spite of these problems, it is written constantly, because it has its own specialty. It has been focused on some works because they reflect awareness of modern times, the democratic idea, and realism. Overall, the authors of Modern Sijo express various themes by using different forms. The more what we can guess in this work, Sijo will exist permanently because of its flexibility. Furthermore, one special characteristic-flexibility of the korean verse will make it last forever and it will be a genre in Korean poetry.

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