• 한국항해학회지
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• 제8권1호
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• pp.49-70
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• 1984

Spatial and temporal variations of hydrography and currents are investigated in the Southeastern Sea of Korea during October 1982. The distribution of the water mass of high salinity (>34.40${\textperthousand}$) and low dissolved oxygen concentration (<5.0ml/l) indicates that the Tsushima current flows northward as it passes the Western Channel of the Korea Strait. The cold water (<$6.0^{\circ}c$) with low salinity (<$34.20{\textperthousand}$) and high dissolved oxygen concentration (>6.0ml/l) reaches the bottom of the western channel of the Korea Strait after flowing southward leaning against the slope rather than following the deepest part of the Channel. Repeated sections in the Korea Strait show a remarkable change of hydrographic structure over a period of 4 days ; both warn and cold waters are intensified, particularly in the eastern part of the strait toward the Tsushima Island.

• 수산해양기술연구
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• 제29권1호
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• pp.1-10
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• 1993

In order to investigate the environmental properties of set net grounds located in the coastal waters of Yeosu, oceanographic observations on the fishing grounds were carried out by the training ship of Yeosu Fisheries University from Jun. 1988 to Dec. 1990. The resultes obtained are summarized as follows; 1) The water mass in the fishing grounds were divided into the inner water (29.50-31.00$\textperthousand$), the mixed water (31.10-32.70$\textperthousand$) and the offshore water (32.70-34.30$\textperthousand$) according to the distribution of salinity from T-S diagram plotted all salinity data observed from Jun. 1988 to Dec. 1990. In spring the mixing water prevailed and in summer the inner and mixing water. But in autumn and winter the mixing and offshore waters prevailed. 2) The inner water which was formed by land water from the river of Somjin and the precipitation in the Yeosu district flowed southerly along the coast of Dolsando and spread south-easterly in the vicinity of Kumodo. The inner water and offshore water which supplied from the vicinity of Sorido and Yokchido formed the thermal front and halofront. 3) As the mixing water flowing from the western sea of Cheju to the southern coast of korea was low in temperature, the water mass of low temperature which appeared at the offshore bottom of Sorido in summer was considered not to be the Tsushima warm current. 4) As vertical mixing was made frequently in spring, autumn and winter, the differences in temperature and salinity between surface and bottom was respectively small. In summer, however, the mixing was not made because of the inner water expanded offshore through the space between surface and 10m layer and so a thermocline of $2.0^{\circ}C$/10m and halocline of 4.0$\textperthousand$/10m respectively in vertical gradient was formed. 5) In the vicinity of Dolsando and Kum a water low in salinity prevailed, but in the vicinity of Namhaedo and YoKchido the reverse took place. The inner and mixing waters formed at these arease was limited to the observation area not to spread widely.

• Journal of the korean society of oceanography
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• 제39권1호
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• pp.72-95
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• 2004

The Yellow Sea is characterized by relatively shallow water depth, varying range of tidal action and very complex coastal geometry such as islands, bays, peninsulas, tidal flats, shoals etc. The dynamic system is controlled by tides, regional winds, river discharge, and interaction with the Kuroshio. The circulation, water mass properties and their variability in the Yellow Sea are very complicated and still far from clear understanding. In this study, an effort to improve our understanding the dynamic feature of the Yellow Sea system was conducted using numerical simulation with the ROMS model, applying climatologic forcing such as winds, heat flux and fresh water precipitation. The inter-annual variability of general circulation and thermohaline structure throughout the year has been obtained, which has been compared with observational data sets. The simulated horizontal distribution and vertical cross-sectional structures of temperature and salinity show a good agreement with the observational data indicating significantly the water masses such as Yellow Sea Warm Water, Yellow Sea Bottom Cold Water, Changjiang River Diluted Water and other sporadically observed coastal waters around the Yellow Sea. The tidal effects on circulation and dynamic features such as coastal tidal fronts and coastal mixing are predominant in the Yellow Sea. Hence the tidal effects on those dynamic features are dealt in the accompanying paper (Kim et at., 2004). The ROMS model adopts curvilinear grid with horizontal resolution of 35 km and 20 vertical grid spacing confirming to relatively realistic bottom topography. The model was initialized with the LEVITUS climatologic data and forced by the monthly mean air-sea fluxes of momentum, heat and fresh water derived from COADS. On the open boundaries, climatological temperature and salinity are nudged every 20 days for data assimilation to stabilize the modeling implementation. This study demonstrates a Yellow Sea version of Atlantic Basin experiment conducted by Haidvogel et al. (2000) experiment that the ROMS simulates the dynamic variability of temperature, salinity, and velocity fields in the ocean. However the present study has been improved to deal with the large river system, open boundary nudging process and further with combination of the tidal forcing that is a significant feature in the Yellow Sea.

• 한국지하수토양환경학회지:지하수토양환경
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• 제21권6호
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• pp.46-55
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• 2016

This experimental study was aimed to estimate interfacial tension of brine-$CO_2$ by using a pendant bubble method and image analysis. Measurements were performed for wide ranges of temperatures, pressures, and salinities covering reservoir conditions in Pohang basin, a possible candidate for $CO_2$ storage operation in Korea. The profiles of $CO_2$ bubbles in brine obtained from image analysis with the densities of brine and $CO_2$ from previous studies were applied to Laplace-Young equation for calculating interfacial twnsion in brine-$CO_2$ system. The experimental results reveals that the interfacial tension is significantly affected by reservoir conditions such as pressure, temperature and water salinity. For conditions of constant temperature and water salinity, the interfacial tension decreases as pressure increases for low pressures (P < $P_c$), and approaches to a constant value for high pressures. For conditions of constant pressure and water salinity, the interfacial tension increases as temperature increases for T < $T_c$, with an asymptotic trend towards a constant value for high temperatures. For conditions of constant pressure and temperature, the interfacial tension increases with increasing water salinity. The trends in changes of interfacial tension can be explained by the effects of the reservoir conditions on the density difference of brine and $CO_2$, and the solubility of $CO_2$ in brine. The information on interfacial tensions obtained from this research can be applied in predicting the migration and distribution of injecting and residual fluids in brine-$CO_2$-rock systems in deep geological environments during geological $CO_2$ sequestrations.

• 한국환경과학회지
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• 제20권12호
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• pp.1521-1531
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• 2011

This study was carried out to determine the characteristics of the marine environment, including nutritional content, in order to clearly understand the outbreaks of Gonyaulax polygramma in the southern coastal areas in August, 2009. Samples were collected at 13 sites and water temperature and salinity were measured using a CTD. Field surveys were twice: the first between August 5-7, the second between August 22-24. The cell density of G. polygramma was 6,500-10,000 cells $ml^{-1}$ during the $1^{st}$ survey, whereas during the $2^{nd}$ survey the range of the cells was recorded from 8,000 to 12,500 cells $ml^{-1}$. Cochlodinium polykrikoides ranged from 0 to 105 cells $l^{-1}$ during the field survey. In water environments, the majority stations during the $1^{st}$ survey showed a nearly homogeneous water column below $1^{\circ}C$ in temperature, as well as similar profiles of salinity. However, the stratification between the surface and bottom was observed in the $2^{nd}$ survey. Regarding nutrients, Dissolved Inorganic Nitrogen (DIN) in the surface ranged from 0.144 to 0.236 mg $l^{-1}$ during the $1^{st}$ survey, and 0.082-0.228 mg $l^{-1}$ during the $2^{nd}$ survey. DIP (Dissolved Inorganic Phosphorus) did not show any difference in concentration between the $1^{st}$ and $2^{nd}$ survey. During August of 2009, the wind speed in the southern waters remained at around ${\leq}2\;m\;s^{-1}$ for about 60% of time, and there was very little precipitation during the month. Irradiance of ${\geq}10$ hr was shown in the late of August. It is thought that a low level of DIN and salinity play an important role as an essential factor for rapid growth, wide distribution and longer duration of red tide in G. polygramma.

• 한국지리정보학회지
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• 제22권3호
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• pp.37-50
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• 2019

본 연구에서는 GIS 기반 공간보간법을 적용하여 새만금 농업용지의 토양 염도를 분석하였다. 연구 대상지 공시토양은 하해혼성 충적층을 모재로 한 문포통 이었으며 토양 표토(0~20cm)와 심토(20~40cm)로 구분하여 토양 시료를 채취하였다. 먼저 142 지점의 샘플을 이용하여 공간보간에 따른 EC, ESP, SAR의 분포특성을 파악하였으며, 143 지점의 검증점에 대한 오차분석을 통해 EC와 SAR은 IDW 방법 그리고 ESP는 Kriging 보간법을 최적의 보간법으로 선정할 수 있었다. 최적의 보간법을 이용하여 EC, ESP, SAR 염분농도 항목별로 2014년에서 2016년 동안의 토양 염도 변화특성을 분석하였다. 분석 결과 EC, ESP, SAR는 강우발생에 따른 희석효과 등으로 각각 0.26mg/L, 5.97mg/L, 0.73mg/L 만큼 감소한 것으로 분석되었다.

• 환경생물
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• 제38권4호
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• pp.625-633
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• 2020

The effects of temperature and salinity on egg development and settlement of the ascidian Herdmania momus were investigated. Adult specimens were collected from the Dodu Yacht facility in Jeju Island, Korea(33°30'30.54"N, 126°27'55.46"E) in August 2018. Egg development and larval settlement were observed and recorded at 8 h intervals using a stereomicroscope, under nine temperature (10, 13, 16, 19, 22, 25, 28, 31, and 34℃), and four salinity regimens (28, 30, 32, and 34 psu). The highest hatching rate (82.8±7%) was observed at 32 psu and 25℃ and the lowest hatching rate (1.0±2%) was at 34 psu and 13℃. The developmental rate (0.222±0.0994) was highest at 28 psu and 28℃, and lowest (0.016±0.008) at 30 psu and 13℃. The highest settlement success rate (77.1±5%) was at 32psu and 25℃ and the lowest(0.1±1.0%) was at 30psu, and 13℃. The rate of settlement(0.080±0.000) was highest at 28psu and 28℃, and lowest(0.013±0.000) at 30psu and 13℃. Both hatching and settlement success rates increased as temperature increased and tended to decrease beyond an optimal temperature range. Herdmania momus preferred 30-34 psu salinity and 22-25℃ temperature. This study provides baseline information about the life history of H. momus, and important data to control the damage caused by the increase in number and distribution of this invasive ascidian.

• 한국해양학회지:바다
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• 제7권2호
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• pp.51-59
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• 2002

섬진강 하구역에서 염분 경사에 따른 동물플랑크톤의 종 조성과 양적 분포를 계절별로 조사하였다. 하구역이라 하나 전 계절 연안역에서 흔히 볼 수 있는 종들이 주를 이루고 있었으며, 전 계절 담수 유래종은 매우 미약하였다. 평균 총량으로 봄에 3,000 개체/m$^3 $이상의 많은 개체수가분포하며 여름에 다소 감소하나 여전히 많은 개체수 분포를보이고 가을에 약 500 개체/m$^3$수준으로 감소하였다가 겨울부터 증가하는 계절적 변동을 보였다. 염분 범위에 따라 저염분역(염분 5 psu이하), 중염분역(5~18 psu), 고염분역(18 psu 이상)으로 나누어 살펴보면, 계절의 진행에 따라 가장 많은 양의 동물플랑크톤이 출현하는 염분역이 일정하게 유지되지 않고 있으며, 종 조성에서도 계절별 지역별로 차이를 보였다. 가을철에는 요각류가 저염분역에서 우세하나 고염분역으로 가면서 갑각류 이외의 종들이 우세하였고, 겨울철에는 전 지역에서 요각류가 우세하였다. 봄철에는 대상 해역이 중염분역과 고염분역으로만 구분되었는데, 중염분역에서는 요각류, 고염분역에서는 야광충이 우점하였다. 여름철에는 저염분역에서는 요각류가, 중염분역과 고염분역에서는 야광충이 더 많았다. 요각류 군집만을 대상으로 염분 구역별 주요 우점 종을 열거하였고, 이들의 출현수온, 염분 범위와 가장 많은 출현량을 보인 지역의 수온 염분을 제시하였다. 이들 요각류의 염분 내성 범위는 매우광범위하게 나타나 지시종의 개념이 요각류에 있어서는 출현 유무라는 정성적인 개념보다는 양의 많고 적음이라는 정량적인 개념에서 사용되어져야 할 것으로 여겨졌다.이 맞닿는 지역으로 Sternaspis scutata가 가장 우점하였다. 과거의 연구와 비교해 보면, 저서다모류군집은 출현종수, 서식밀도와 우점종에 있어서 큰 변화를 보였다. 과거의 조사결과에서는 우점종이 Sternaspis scutata와 Eteone longa이었으나, 본 조사에서는 이 종들의 서식밀도가 감소하였다. 반면에 잠재적 유기물 오염 지시종으로 알려진 Lumbrineris longifolia와 Heteromastus filiformis가 서식밀도는 낮지만 새롭게 우점종으로 대두하였다. 이러한 사실들로 볼 때, 득량만은 한국의 다른 만들과는 달리 아직까지 오염이 덜한 해역인 것으로 사료되나, 환경관리에 주의를 요하는 것으로 판단된다. 공간분포는 다양한 무기 환경 요소들 가운데 일차적으로 저층수의 염분에 의해 영향을 받으며, 이차적으로 퇴적상에 의해 영향을 받고 있음을 알 수 있다.한 결과, $CH_4$ 농도의 증가율이 무안과 태안 지역에서 각각 연간 16.5, 14.8 ppb로 가장 높게 관측되었다. 관측점 주변에 복잡한 배출원의 작용이 가능하다는 점을 감안하여, 무안지역의 $CH_4$ 농도변화와 풍향과의 연계성을 비교해 보았다. 이 결과에 의하면, 동풍계열의 풍계가 나타날 때 고농도의 값이 나타났으며, 청정한 공기가 유입되는 남서풍의 풍계시에는 비교적 낮은 $CH_4$ 농도가 유지되었다. 이처럼 $CH_4$의 장주기적 분포특성은 연구대상지역의 복잡한 배출${\cdot}$소별작용과 연계되어 매우 다양하고 독특한 형태를 띠고 있음을

• 수산해양기술연구
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• 제34권2호
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• pp.117-134
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• 1998

The study on the Assembling Mechanism of the Hairtail, Trichiurus lenpturus, at the Fishing Grounds of the Cheju Strait had been investigated by analyzing the relationship of the oceanographic conditions and the fishing ground of the Hairtail in the Cheju Strait. 1. The fishing grounds of the hairtail at the Cheju Strait are formed at the bottom of a high temperature of the tidal front at the coast. area of northern Cheju Island, the tip of the linguiform is high in salinity at the eastern and western entrances of Cheju Island, low salinity eddy on the surface and its surrounding front, various water masses in the Strait and coastal waters of the South Sea in Korea. 2. The fishing grounds of the Hairtail at the Cheju Strait begins with the sea surface temperature higher than $15^{\circ}C$ and the incoming of low salinity water now from the East China Sea. 3. Estimation of optimum temperature and salinity per season based upon analysis for relationship between temperature of water and salinity of the bottom layer and the catch is : 15.2~$16.4^{\circ}C$, 34.20~34.40${\textperthousand}$ in spring(June); 14.4~ $17.0^{\circ}C$, 33.70~34.30${\textperthousand}$ in summer(July~September); and 15.7~ $18.6^{\circ}C$, 33.70~34.50$\textperthousand$ in autumn(October~December). Hairtail are mostly caught at the Yellow Sea Warm Current and Tsushima Current with temperature over $14.5^{\circ}C$ and salinity over 33.70${\textperthousand}$ at the bottom layers of the Cheju Strait. 4. Considering the relationship between the amount of hairtail catch and the water temperature of bottom layer, when the bottom water being above $14.0^{\circ}C$ flowed into Cheju Strait through the western entrance of the strait in summer, the ca-h appears to have been abundant. In contrast, the catch has been poor when the temperature of such water was recorded to be below $13^{\circ}C$ Therefore, distribution patterns of water at the bottom layer can be used as a forecast index whether the catch of a certain year will be good or poor.

• 수산해양기술연구
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• 제35권2호
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• pp.102-117
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• 1999

본 연구에서는 국립수산진흥원 소속 부산 851호에 의해 1987~1990년 (4개년)과 1992~1993년 (2개년)의 하계 (7~9월)에 북태평양 ($34^{\circ}~47^{\circ}N,\;150^{\circ}\;E~170^{\circ}W$)에서 오징어채낚기 (오징어손줄낚시)에 의해 시험조업하여 어획된 6종의 오징어를 대상으로 하여 분석한 오징어종류별 어획수충, 해양환경(수온, 염분) 및 어획률을 분석하였으며 그 결과는 다음과 같다. 1. 문어오징어는 아한대영역의 위도 $41^{\circ}~43^{\circ}N$ 인 71~80m 수층의 수온 6~11^{\circ}C$, 염분 33.2~$33.6{\textperthousand}$인 해역에서 높은 어획률을 보였다. 2. 갈구리오징어는 아한대영역의 위도 $41^{\circ}~42^{\circ}N$인11~20m 수층의 수온 10~12^{\circ}C$, 염분 32.9~$33.6{\textperthousand}$인 해역에서 높은 어획률을 보였다. 3. 살오징어는 아한대영역 및 이행영역의 위도 $40^{\circ}\;및\;42^{\circ}N$인 11~20m 수층의 수온 15~18^{\circ}C$,염분 33.6~34.0$\textperthousand$인 해역에서 높은 어획률을 보였다. 4. 빨강오징어는 아한대수렴선 및 이행영역의 위도 $39^{\circ}~41^{\circ}N$인 표층~10m 수층의 수온 16~17^{\circ}C$, 염분 33.7~$34.4{\textperthousand}$인 해역에서 높은 어획률을 보였다. 5. 두줄무늬빨강오징어는 아열대영역의 위도 $37^{\circ}~39^{\circ}N$인 11~20m 수층의 수온 18~20^{\circ}C$, 염분 33.8~$34.6{\textperthousand}$인 해역에서 높은 어획률을 보였다. 6. 노랑점빨강오징어는 아열대영역의 위도 $36^{\circ}~37^{\circ}N$인 표층~10m 수층의 수온 24~25^{\circ}C$, 염분 34.2~$34.4{\textperthousand}$$\textperthousand$ 인 해역에서 높은 어획률을 보였다.