• Title/Summary/Keyword: 해수 영향

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On the Marine Environment and Distribution of Phytoplankton Community in the Northern East China Sea in Early Summer 2004 (이른 여름 동중국해 북부해역의 해양환경과 식물플랑크톤 군집의 분포특성)

  • Yoon, Yang-Ho;Park, Jong-Sick;Soh, Ho-Young;Hwang, Doo-Jin
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.8 no.2
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    • pp.100-110
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    • 2005
  • We carried oui a study on the marine environment and distribution of phytoplankton community, such as chlorophyll a, species composition, dominant species and standing crops in the Northern East China Sea during early summer of 2004. According to the analysis of a T-S diagram, three characteristics of water masses were identified. We classified them into the coastal water mass, the cold water mass and the oceanic water mass. The first was characterized by the low temperature and the low salinity originated from China territory, the secondary was characterized by the low temperature, the low salinity and the high density originated from bottom cold water of Yellow Sea, and the third was done by the high temperature and salinity originated from Tsushima warm current. The internal discontinuous layer among them was farmed at the intermediate depth (about $5{\sim}30m$ layer). And the thermal front by upwelling region between the cold water mass and Tsushima warm current appeared in the central parts of the South Sea of Korea. The Phytoplankton community in the surface and stratified layers was a total of 44 species belonging to 26 genera. Dominant species were Prorocentrum triestinum, Scrippsiella trochoidea, Skeletonema costatum & Leptocylindrus mediterraneus. Standing crops of phytoplankton in the surface layer fluctuated between $0.3{\times}10^3$ cells/L and $10.8{\times}10^3$ cells/L. Diatoms appeared mainly in the Tsushima warm current regions, and flagellates occurred in the frontal zone and the low salinity regions where was the transfer areas of Chinese continental coastal waters. Chlorophyll a concentration by controlled phytoflagellate ratio in the South Sea of Korea was high values in the frontal zone and sub-surface layer. It was high concentration in the upwelling and coastal waters regions, but low concentration in the Tsushima warm current regions. The Chl-a maximum layers appeared in the thermochline depth or sub-surface layer lower than thermocline. The phytoplankton production in the South Sea of Korea was controlled by the expanded coastal waters of Chinese Continent which include a high concentrations of nutrients.

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소적백출산(消積白朮散)이 항암효과(抗癌效果) 및 Cisplatin부작용(副作用) 감소(減少)에 미치는 영향(影響)

  • Jo, Jong-Gwan
    • Journal of Haehwa Medicine
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    • v.4 no.2
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    • pp.255-272
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    • 1996
  • 소적백출산(消積白朮散)은 ${\ll}$화제국방(和劑局方)${\gg}$에 삼령백출산(蔘笭白朮散)에 정열해독약(淸熱解毒藥)인 와송(瓦松) 금은화(金銀花) 포공영(蒲公英)을 가미(加味)한 처방(處方)으로, 본방(本方)인 삼령백출산(蔘笭白朮散)은 비위허약(脾胃虛弱), 음식부진(飮食不振), 다곤소력(多困少力) 중만비대(中滿痺臺), 심정기천(心柾氣喘), 구토(嘔吐), 설사(泄瀉), 상한해수(傷寒咳嗽)를 치료목적(治療目的)으로 쓰여 온 이래(以來) 임상에서는 대편부실(大便不實), 구설(久泄), 옹달궤후(癰疸潰後) 불사식자(不思食者)를 치료(治療)하는데 다용(多用)되어 왔다. 종양(腫瘍)(Neoplasia)은 새로운 성장(成長)(New+ Glowth) 이라는 세포학적(細胞學的)으로 비정상세포(非正常細胞)의 과다증식(過多增殖)으로 인해 실질장기(實質臟器), 유강장기(有腔腸器), 및 골격(骨格), 피부조직(皮膚組織)에 비정상조직(非正常組織)을 형성(形成)하는 질환(疾患)이다. 현대적(現代的) 종양(腫瘍)과 유사(類似)한 한의학적(韓醫學的)인 병증(病症)은 ${\ll}$소문(素問)${\gg}$에서는 "궐산(厥疝), 복량(伏梁), 식적(息積)"으로 ${\ll}$영추(靈樞)${\gg}$에서는 "장담(腸覃), 석가"로 표시(表示)된 이후(以後)로 소원방(巢元方)은 징가, 식일, 석옹(石癰), 완저(緩疽), 석저(石疽) 등으로 표현(表現)하였다. 원인(原因)에 대(對)해서는 ${\ll}$내경(內經)${\gg}$에서는 허(虛)와 한기(寒氣), 한(寒) 열(熱)로 보았고, 그 외(外)의 학자(學者)들은 내허(內虛)와 기혈불순(氣血不順), 화(火), 한(寒), 기울(氣鬱), 음양불화(陰陽不和)등으로 보았다. 치료(治療)는 ${\ll}$내경(內經) 자법론(刺法論)${\gg}$에서 "정기재내(正氣在內) 사불가우(邪不可于)" 이라 하여 생명활동(生命活動)의 원동력(原動力)인 정기(正氣)의 역할(役割)을 강조(强調)하였고, ${\ll}$육원정기대론(六元正氣大論)${\gg}$에서는 "대적대취(大積大聚) 불가범야(不可犯也) 쇠기태반이지(衰其太半而止)"라 하여 공벌약(攻伐藥)을 과용(過用)하여 정기(正氣)를 손상(損傷)시켜서는 안된다고 하는 등 부정위주(扶正爲主), 거사위주(祛邪爲主) 혹은 부정거사(扶正祛邪) 겸용(兼用)의 방법(方法)이 혼용(混用)되고 있다. 현대(現代) 서양의학(西洋醫學)의 항암제(抗癌劑)는 치료효과(治療效果)는 우수(優秀)하지만 악심(惡心), 구토(嘔吐)를 비롯하여 골수억제효과(骨髓抑制效果)와 간(肝), 심(心), 신(腎), 폐(肺)의 손상(損傷)을 초래(招來)하는 등(等)의 부작용(副作用)을 나타내며, 빈번(頻繁)한 화학요법제(化學療法劑)의 투여(投與)로 인(因)한 암세포(癌細胞)의 약제저항성(藥劑抵抗性) 출현(出現)등이 항암제(抗癌劑)의 문제점(問題點)으로 제시(提示)되고 있다. 이에 저자(著者)는 비위기능(脾胃機能)을 강화(强化)시켜 정기형성(正氣形成)에 깊이 관여(關與)하는 삼령백출산(蔘笭白朮散)에 청열해독(淸熱解毒), 소종산결지제(消腫散結之劑)인 금은화(金銀花), 포공영(浦公英), 와송(瓦松)을 가미(加味)하여 암발생(癌發生) 백서(白鼠)에 투약(投藥)한 후(後) sarcoma 180암세포(癌細胞)에 대(對)한 생명연장효과(生命延長效果)와 항암제(劑)의 일종(一種)인 cis-platin을 이용(利用)하여 양방항암제(洋方抗癌劑)의 부작용(副作用)에 대(對)한 본(本) 방(方)의 효과(效果)를 실험(實驗)하여 관찰(觀察)하였던 바 다음과 같은 결론(結論)을 얻었다. 1. 소적백출산(消積白朮散)은 sarcoma 180 암세포(癌細胞) 이식종양(移植腫瘍)에 대(對)해 생명연장효과(生命延長效果)가 인정(認定)되었다. 2. 소적백출산(消積白朮散)은 치암제(治癌劑)인 cis-platin 치사독성(致死毒性)에 대(對)해 생존연장효과(生存延長效果)가 인정(認定)되었다. 3. 소적백출산(消積白朮散)은 cis-platin 현독성(腎毒性) 생쥐 및 흰쥐에 있어서 유의성(有意性) 있는 체중감소억제효과(體重減少抑制效果) 및 serum BUN 상승억제효과(上昇抑制效果)가 인정(認定)되었다. 4. 소적백출산(消積白朮散)은 cis-platin 현독성(賢毒性) 흰쥐에 대(對)해 유의성(有意性) 있는 serum creatinine 상승억제효과(上昇抑制效果)가 나타났으며, cis-platin의 혈액학적(血液學的) 부작용(副作用)인 RBC, WBC 감소(減少)에 대(對)해 감소억제효과(減少抑制效果)가 인정(認定)되었다. 5. 소적백출산(消積白朮散)은 cis-platin 현독성(腎毒性) 흰쥐에 대(對)해 뇨량감소억제(尿量減少抑制) 효과(效果) 및 ureanitrogen과 creatinine 배수감소억제효과가 관찰(觀察)되었다. 이상(以上)의 결과(結果)로부터 소적백출산(消積白朮散)은 악성종양치료(惡性腫瘍治療) 및 항암제(劑)의 부작용(副作用)을 경감(輕減)시키는 데 응용(應用)할 수 있을 것으로 사료(思料)된다.

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Morphological Adaptation of Zostera marina L. to Ocean Currents in Korea (한국산 거머리말(Zostera marina L.)의 해류에 대한 형태적 적응)

  • Lim, Dong-Ok;Yun, Jang-Tak;Han, Kyung-Shik
    • Korean Journal of Environment and Ecology
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    • v.23 no.5
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    • pp.431-438
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    • 2009
  • The main purpose of this research is to prepare and provide basic materials for the propagational strategy of eelgrass by investigating on the morphological adaptation of Korean Zostera marina to ocean currents. An eelgrass plant mainly consists of rhizome, leaf sheath, leaves and roots. The rhizome is the horizontal stem of the plant that serves as the backbone from which the leaves and roots emerge. The leaf sheath is the bundle at the base of the leaves that holds the leaves together, protecting the meristem, the primary growth point of the shoot. Leaves originate from a meristem which is protected by a sheath at the actively growing end of the rhizome. As the shoot grows, the rhizome elongates, moving across or within the sediment, forming roots as it progresses. The aggregated leaves from the leaf sheath are found to have two cell layers on one side and multiple layers of airy tissues called aerenchyma on the other. The aerenchyma tissues are developed in multi-layered cell structures surrounding the veins which are formed in the leaf sheath. Generative shoots are made of rhizomes, which are circular or ovoidal, stem, and spathe and spadix. The transverse section of rhizome and the stem and central floral axis is found to be circular, ovoid and in the shape of convex respectively, and the vascular bundle, which is a part of transport system, has one large tube in the center and two small tubes on both sides. The layers of collenchyma cells numbered from 12 to 15 in the stem, and from 7 to 12 in the rhizome. The seed coat is composed of sclereids, small bundles of sclerenchyma tissues, which prevent the influx of sea water from the outside and help endure the environmental stress. In conclusion, alternative multi-layer structure in circular, convex type aggregated leaf base are interpreted to morphological adaption as doing tolerable elastic structure through movement of seawater. The generative shoots develop long slim stem and branches in circular or ovoidal shapes to minimize the adverse impacts of sea current, which can be interpreted as the plant's morphological adaptation to its environment.

Studies on the Environmental Characteristics of the Breeding Ground in the Kogum-sudo, Southern Part of Korean Peninsula I. Seasonal Succession of Phytoplankton Population (거금수도내 양식어장의 해양환경특성 I. 식물플랑크톤 군집의 계절변동)

  • Yoon Yang Ho;Koh Nam Pyo
    • Journal of Aquaculture
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    • v.8 no.1
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    • pp.47-58
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    • 1995
  • Field studies on the seasonal succesion of phytoplankton population were carried out at the 25 stations of the breeding ground in Kogum-sudo, Southern coast of Korean peninsula in Feburuary, April, August and October, 1993. Sixty four species belonging to 40 genera were identified. Predominant species were mainly centric diatoms throughout the four seasons, two centric diatoms, Skeletonema costatum and Thalassiosira sp. and a pennate diatom, Thaiassionema nitzschioides in the winter; two pennate diatoms, Thaiassionema nitzschioides and Asterionella kariana, and especially a dinoflagellate, Heterocapsa triquetra (station 10) in the spring, two centric diatoms, S. costatum and Chaetoceros diadema in the summer; and a centric diatom, Rhizosolenia alata and a pennate diatom, Bacillaria paxillifer in the fall. The main red tide organisms in the breeding ground were dinoflagellates, Prorocentrum dentatum, P. minimum, P. triestinum, Ceratium furro, Gymnodinium sanguineum, Noctiluca scintillans, H. triquetra, Scrippsiella trichoidea and a diatom S. costatum in the Kogum Sudo. Seasonal phytoplankton cell numbers were in a wide range between $8.8\times10^3$ cells/l and 1.4\times10^6$ cells/l; The seasonal average cell numbers were $12.2\times10^4\pm5.9\times10^4$ cells/l $(mean\;\pm\;standard\; diviation)$ in the winter, $3.3\times10^4\pm1.4\times10^4$ cells/l in the spring, $48.4X10^4\pm40.0\pm10^4$ cells/l in the summer, and $3.6\times10^4\pm1.9\times10^4$ cells/l in the fall, respectively.

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Growth and morphological characteristics of Polygonatum species indigenous to Korea (한국산 둥굴레속(Polygonatum) 수집종의 생육 및 형태적 특성)

  • Yun, Jong-Sun;Son, Suk-Yeong;Hong, Eui-Yon;Kim, Ik-Hwan;Yun, Tae;Lee, Cheol-Hee
    • Korean Journal of Plant Resources
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    • v.15 no.2
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    • pp.164-171
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    • 2002
  • Morphological characteristics and growth pattern of 10 Polygonatum collections indigenous to Korea were examined to select the promising medicinal, edible resources and horticultural crops. Plant heights of I0 collections ranged from 15 to 102cm. Stem type was ascending or erect, and node numbers per a stem was 6.2 to 23.2. Phyllotaxis type was alternate or verticillate, and leaf shape was elliptical or linear. Leave numbers per a stem was 5.2 to 63.4, and bract types were classified into bracteate and nonbracteate. Flowers bloomed from May 7 to May 30, and flowering period was 5 to 13 days. Inflorescence types were classified into racemose, corymbose, and umbellate. Flower numbers per a stem was 1.5 to 125.2, and flower length was 13.1 to 30.2㎜. Perianth shapes were classified into tubular, constrict and urceolate. Surface colors of rhizome were pale yellow, pale brown, brown, and dark brown. As a result of this experiment, P. sibiricum, P. odoratum var. pluriflorum and P. odoratum var. thunbergii were thought to be useful as the medicinal and edible resources plants. On the other hand, P. odoratum var. pluriflorum 'Variegata', and P. odoratum var. maximowiczii, P. lasianthum. P. involucratum, P. desoulavyi, P. humile, and P. inflatum were thought to be useful as horticultural plants.

Temporal and Spatial Variations of Water Quality in the Cheonsu Bay of Yellow Sea, Korea (천수만 수질환경의 시·공간적 변동특성)

  • Park, Soung-Yun;Heo, Seung;Yu, Jun;Hwang, Un-Ki;Park, Jong-Su;Lee, Sung-Min;Kim, Chang-Mi
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.19 no.5
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    • pp.439-458
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    • 2013
  • Temporal and spatial variations of water quality were investigated in the Cheonsu Bay of Yellow Sea, Korea from 2010 to 2011. Water samples were collected at 16 stations and physicochemical parameters were analyzed including water temperature, salinity, suspended solids (SS), chemical oxygen demand (COD), dissolved oxygen (DO), Chlorophyll a and nutrients. Spatial distribution patterns of all survey items were not clear among stations but the bimonthly variations were distinct except the bottom water of the suspended solids. The trend analysis by principal component analysis (PCA) during 2 years revealed the significant variations in water quality in the study area. Spatial water qualities were discriminated into 3 clusters by PCA; station cluster in the surface water 1, 2~11, and 12~16, the bottom water 1, 2~7, and 8~16. Annual bimonthly water qualities were clearly discriminated into 3 clusters by PCA. But tend of cluster in the surface and bottom water was difference, period most of the research was low in nutrient. Ecology-based water quality criteria was a good level of grade II. Bimonthly results are shown as III grade(normal) at June and August, II grade(good) at October and December and I grade for February and April. Water quality was showed by the input of fresh water same as those of Kyoungin coastal area, Asan coastal area, Gunsan coastal and Mokpo coastal area in the Cheonsu.

Hydrochemical characteristics in groundwater affected by reclamation (해안가 매립으로 인한 지하수의 수리화학적 특성)

  • 서정율
    • The Journal of Engineering Geology
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    • v.14 no.1
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    • pp.1-20
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    • 2004
  • This study focuses on the hydrochemical characteristics in goundwater affected by reclamation at 2000 Sydney Olympic Games site, Sydney, Australia. The Olympic Games site can be divided into three areas, i.e. reclaimed areas; landfill areas and non-infilled areas. In the current work, 'reclaimed areas' were previously estuarine, and were filled with waste materials and are now above present high tide level, whereas 'landfill areas' are areas where deposition of waste materials occurred above sea level. No deposition of waste took place in 'non-infilled areas'. This study was also evaluated by three different types such as deep boreholes, shallow boreholes and standpipes. The hydrochemishy of groundwaters in reclaimed and non-in-filled areas is characterized by Mg- and Ca-enrichment, whereas groundwaters in landfill areas are elevated in K and NO₃. Na, K and Mg are the dominant cations in groundwater from reclaimed areas and Na and K are the dominant cations in groundwater in landfill areas. Na and Mg are the dominant cations in groundwater in deep boreholes, whereas Na and K are the dominant cations in groundwater in shallow boreholes and standpipes. There is no distinct trend in heavy metals with electrical conductivity in the groundwater between the re-claimed, landfill and non-infilled areas. Fe and Mn in landfill areas with respect to reclaimed areas and non-infilled areas show a distinct increase in concentration with declining pH. Mean electrical conductivity values in the deep and shallow boreholes are higher than that of standpipes, but the minimum and maximum value of electrical conductivity in groundwater in standpipes shows remarkably different value, probably due to perched pond. There is no correlation between Cu, Pb, Zn, Cr concentrations in groundwater with pH, from deep boreholes, shallow boreholes and standpipes, except for Fe and Mn, which demonstrate increasing concentrations with declining pH. The results revealed a close association between elevated concentrations in groundwater and the presence of fill materials at the site. Trace metals teachability from re-claimed soils adjacent to estuary plays a significant role in determining their potential environmental risk to surrounding environment.

Sedimentary facies and micropaleontological study of tidal sediments off the Mankyung-Dongjin River estuary, west coast of Korea. (한국 서해 만경강-동진강 하구역 및 연안역 조간대 퇴적층의 퇴적상과 미고생물학 적 연구)

  • 이영길;박용안
    • 한국해양학회지
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    • v.30 no.2
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    • pp.77-90
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    • 1995
  • The sedimentary environments and biostratigrapy of the tidal sediments off the Mankyung-Dongjin River estuary were studied based on sedimentary facies and diatom assemblage analysis. Sediment facies from the five vibracores are mainly clay, silt, and sand facies. The clay and silty sediment facies are more dominant than the sandy facies, and contain diatom frustules. The frequency of the diatom frustules are rate to common, but not found in sandy sediment facies. Bigeneric structures such as burrow and non-bigeneric primary sedimentary structures such as laminated sand and mud or silt and mud couplets, flaser bedding, ripple-cross lamination are found in several stratigraphic levels of the sedimentary sequences. A total of 219 species and varieties, belonging to 61 genera has been identified in the present study. Among them, paralia sulcata is the most abundant species about 30 to 50% of the total diatom frustules. Another predominant species are Cyclotella striata. Thalassionema nitzschioides. Actinoptychus undulatus. Delphineis surirella, Raphoneis amphiceros. Most of the diatoms occurred in this study area are marine, marine-brackish water, and brackish water species, and are benthic and tychopelagic or meroplanktonic species. Also, most of the species are coastal to littoral and littoral to inner neritic species. The occurrences of freshwater species, about 1 to 5% is higher than that of the Namyang Bay tidal sediments. The ecological properties of the diatoms occurred in the study area and primary sedimentary structure such as flaser bedding ripple cross bedding indicate that the deposits are formed under coastal or littoral to subeditorial environments such as tidal zone which was subjected to the influenced of stream water and was more strongly influenced by temperate to warm water than cold water. The sedimentary environments have not been changed distinctively during the time of deposition. The vertical distribution pattern of diatoms in the study area is studied by Q-mode cluster Analysis using spss/pc+ (ver.4.0). The results show that the three cores (GE-3, GE-11, GE-12) are divided into two diatom assemblages, respectively. Biostratigraphic correlation using the data of Q-mode Cluster Analysis are attempt in this study.

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Lithium Distribution in Thermal Groundwater: A Study on Li Geochemistry in South Korean Deep Groundwater Environment (온천수 내 리튬 분포: 국내 심부 지하수환경의 리튬 지화학 연구)

  • Hyunsoo Seo;Jeong-Hwan Lee;SunJu Park;Junseop Oh;Jaehoon Choi;Jong-Tae Lee;Seong-Taek Yun
    • Economic and Environmental Geology
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    • v.56 no.6
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    • pp.729-744
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    • 2023
  • The value of lithium has significantly increased due to the rising demand for electric cars and batteries. Lithium is primarily found in pegmatites, hydrothermally altered tuffaceous clays, and continental brines. Globally, groundwater-fed salt lakes and oil field brines are attracting attention as major sources of lithium in continental brines, accounting for about 70% of global lithium production. Recently, deep groundwater, especially geothermal water, is also studied for a potential source of lithium. Lithium concentrations in deep groundwater can increase through substantial water-rock reaction and mixing with brines. For the exploration of lithim in deep groundwater, it is important to understand its origin and behavior. Therefore, based on a nationwide preliminary study on the hydrogeochemical characteristics and evolution of thermal groundwater in South Korea, this study aims to investigate the distribution of lithium in the deep groundwater environment and understand the geochemical factors that affect its concentration. A total of 555 thermal groundwater samples were classified into five hydrochemical types showing distinct hydrogeochemical evolution. To investigate the enrichment mechanism, samples (n = 56) with lithium concentrations exceeding the 90th percentile (0.94 mg/L) were studied in detail. Lithium concentrations varied depending upon the type, with Na(Ca)-Cl type being the highest, followed by Ca(Na)-SO4 type and low-pH Ca(Na)-HCO3 type. In the Ca(Na)-Cl type, lithium enrichment is due to reverse cation exchange due to seawater intrusion. The enrichment of dissolved lithium in the Ca(Na)-SO4 type groundwater occurring in Cretaceous volcanic sedimentary basins is related to the occurrence of hydrothermally altered clay minerals and volcanic activities, while enriched lithium in the low-pH Ca(Na)-HCO3 type groundwater is due to enhanced weathering of basement rocks by ascending deep CO2. This reconnaissance geochemical study provides valuable insights into hydrogeochemical evolution and economic lithium exploration in deep geologic environments.

Bathymetric and Topographic Changes of the Gomso-Bay Tidal Flat, West Coast of the Korean Peninsula (한반도 서해안 곰소만 갯벌의 수심 및 지형 변화)

  • Jin Ho Chang;Yong-Gil Kim;Myong Sun Lee
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.6
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    • pp.552-561
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    • 2023
  • The seafloor topography of Gomso Bay on the west coast of Korea was investigated using subtidal bathymetry and tidal-flat altimetry. Gomso Bay consists of 80% tidal flats and 20% subtidal zone, and is divided into an outer bay and an inner bay by the Jujincheon esturary channel. The outer bay tidal flat, has few tidal channels, has a concave topographic profile, and is characterized by the development of chenier and intertidal sand bars, giving it the appearance of gently sloping, dissipative beaches. The inner bay tidal flat has wide upper and middle tidal flats with a well-developed tidal channel system without cheniers. Moreover, the topographical cross-section between these tidal channels is convex upward, and shows the characteristics of a depositional environment greatly influenced by tidal channels and tidal action. An analysis of the horizontal movement of the tidal flat environment over the past 37 years investigating changes in the iso-depth lines in the Gomso-Bay tidal flat between 1981 and 2018 revealed that the Gomso-Bay tidal flat retreated gradually landward. As a result of analyzing the erosion and sedimentation characteristics of Gomso Bay, assuming that most of the water depth changes were due to changes in the elevation of the sea floor and sea level, an average of 1 cm (0 mm/y) of sediment was eroded in the outer bay over the past 37 years (1981-2018), In the inner bay, an average of 50 cm (14 mm/y) was deposited. Notably, the high tidal flats of the outer bay were largely eroded. Monitoring photographs of the coast showed that most of the erosion of the high tidal flats in the outer bay occurred in a short period around 1999 (probably 1997-2002), and that the erosion resulted from the erosion of sand dunes and high-tide beaches caused by temporarily greatly raised high tide levels and storms.