• Title/Summary/Keyword: high salinity

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Effects of Salinity, Temperature and Food Type on the Uptake and Elimination Rates of Cd, Cr, and Zn in the Asiatic Clam Corbicula fluminea

  • Lee, Jung-Suk;Lee, Byeong-Gweon
    • Ocean Science Journal
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    • v.40 no.2
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    • pp.79-89
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    • 2005
  • Laboratory radiotracer experiments were conducted to determine assimilation efficiencies (AE) from ingested algal food and oxic sediment particles, uptake rates from the dissolved phase, and the efflux rates of Cd, Cr and Zn in the Asiatic clam Corbicula fluminea. Among three elements, AE from both algal and sediment food was greatest for Cd, followed by Zn and Cr. The AEs of tested elements from algal food (Phaeodactylum tricornutum) were consistently higher than those from sediments at a given salinity and temperature. The influence of salinity (0, 4 and 8 psu) and temperature (5, 13 and $21^{\circ}C$) on the metal AEs was not evident for most tested elements, except Cd AEs from sediment. The rate constant of metal uptake from the dissolved phase $(k_u)$ was greatest for Cd, followed by Zn and Cr in freshwater media. However, in saline water, the $(k_u)$ of Zn were greater than those of Cd. The influx rate of all tested metals increased with temperature. The efflux rate constant was greatest for Cr $(0.02\;d^{-1})$, followed by Zn $(0.010{\sim}0.017\;d^{-1})$ and $Cd\;(0.006\;d^{-1})$. The efflux rate constant for Zn in clam tissues depurated in 0 psu $(0.017\;d^{-1})$ was faster than that in 8 psu $(0.010\;d^{-1})$. Overall results showed that the variation of salinity and temperature in estuarine systems can considerably influence the metal bioaccumulation potential in the estuarine clam C. fluminea. The relatively high Cd accumulation capacity of C. fluminea characterized by the high AE, high dissolved influx rate and low efflux rate, suggested that this clam species can be used as an efficient biomonitor for the Cd contamination in freshwater and estuarine environments.

Stratification Variation of Summer and Winter in the South Waters of Korea (한국남해의 여름과 겨울철 성층변동)

  • Lee, Chung-Il;Koo, Do-Hyung;Yun, Jong-Hwui
    • Proceedings of KOSOMES biannual meeting
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    • 2007.05a
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    • pp.43-50
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    • 2007
  • In order to calculate the strength and to. see the variation af the stratification in the Southern Waters af Korea, the stratification parameter defined as potential energy anomaly (PEA, $V(J/m^3)$) introduced by Simpson and Hunter (1974) was used The data used in this paper were observed in August 1999 and February 2000 by National Fisheries Research and Development Institute (NFRDI). Also to know the effects af the temperature and the salinity an the stratification respectively, averaged temperature and salinity were used in the process af calculation the parameter. V is generally high in the offshore. However, in February, V in the onshore is higher than that of the offshore due to the vertical temperature gradient caused by the expansion of South Korean Coastal Waters (SKCW). In the summer, the increase af the atmospheric heating, the temperature inversion phenomenon act an the stratification as the buoyancy forcing. In most cases, the effects of the temperature on the stratification is stronger than that of the salinity. The temperature effect is predominantly due to the extent af the intrusion of Tsushima Warm Current into the study area. However, at stations where V is high the effect af the salinity is also significant. In the winter, V is very low due to the decrease of the buoyancy forcing, but same stations show the relatively high V due to the expansion of SKCW and Tsushima Warm Current.

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Effect of Na+ ion on Changes in Hydraulic Conductivity and Chemical Properties of Effluent of Reclaimed Sandy Soil Column (토양중 Na+ 이온이 간척지 토주의 수리전도도와 용출수의 화학성 변화에 미치는 영향)

  • Ryu, Jin-Hee;Chung, Doug-Young;Yang, Chang-Hyu;Lee, Sang-Bok;Choi, Weon-Young;Kim, Si-Ju
    • Korean Journal of Soil Science and Fertilizer
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    • v.42 no.6
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    • pp.454-459
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    • 2009
  • In order to identify the effect of soil salinity on saturated hydraulic conductivity in reclaimed paddy soils, we established the soil columns uniformly packed with soils collected at every 20 cm up to 60 cm from the reclaimed paddy area with high and low salinity which has been cultivated rice plants for the last 30 years. The soil textures were sandy loam and loamy sand for high-salinity and low-salinity topsoils, respectively. For high-salinity and low-salinity soils the ECes were ranged from 25.2 to $37.8dS\;m^{-1}$ and 3.0 to $3.4dS\;m^{-1}$ while the ESPs were ranged from 7.70 to 20.84 % and from 5.12 to 11.33 %, respectively. The bulk densities of the soil columns were adjusted to $1.15{\pm}0.03g\;cm^{-3}$. The results of the soil column experiments shows that the stabilized saturated hydraulic conductivity of low-salinity soil was $0.62cm\;hr^{-1}$ at the topsoil while there were little water flow at the bottom of the soil columns packed with high-salinity soils. After removal of $Na^+$ ions with $1N\;NH_4OAc$ from the high-salinity soil, Ksat of the saline soil was drastically increased to $0.23cm\;hr^{-1}$. Soil columns of high-salinity topsoil treated with four different concentration of NaCl influent after removal of soluble and exchangeable cations with $1N\;NH_4OAc$ show Ksat in the range of $0.1{\sim}0.15cm\;hr^{-1}$ and the Ksat slightly decreased as the concentration of NaCl influent was increasing. Conclusively, we could assume that $Na^+$ can be significantly contributed to the saturated hydraulic conductivity in newly reclaimed sandy soil.

Microbial population in Han River estuary (한강하류 감조수역에 있어서의 미생물분포)

  • Hong, Soon-Woo;Hah, Yung-Chil;Lee, Kwang-Woong
    • Korean Journal of Microbiology
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    • v.6 no.4
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    • pp.107-112
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    • 1968
  • Examining the microbial populations in the Han River estuary, we conducted this experiment at six sites of the estuarine area, Chollyu-ri, Cholsan-ri, Wolgon-ri, Chogi-ri, Inhwa-ri, and Oepo-ri for 5 months since May 1967. From the results obtained it could be summarized as follows. 1) The salinity of the estuarine water increased in order of the distances from the base point of the Old Han River Bridge to every site of the estuary, and pH of the water, which were between 7. 3 and 8. 1, showing little difference each other in both the sites and dates of experiment. 2) The populations of the general bacteria and coliform group bacteria were highest at the site of Chollyu-ri, and it decreased with the downstreaming of the river water toward Oepo-ri site. As for fungi which have comparatively high tolerance to the salinity, its population was shown hi hest at Chogi-ri. 3) The relationship between the salinity and the number of the general bacteria have indicated that the incresed salinity reduced the growth rates of the bacteria. By this it can be assumed that the fresh-water bacteria decreased due to the sea water as well as its dilution effects. 4) The high pollution of the esturarine water was caused by the increases of inhabitants and water thrown by industries in Seoul and Kyung-In Industrial District as well as the excrements fertilized to the farms.

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Growth and nutrient bioextraction of Gracilaria chorda, G. vermiculophylla, Ulva prolifera, and U. compressa under hypo- and hyper-osmotic conditions

  • Wu, Hailong;Shin, Sook Kyung;Jang, Sojin;Yarish, Charles;Kim, JangKyun
    • ALGAE
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    • v.33 no.4
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    • pp.329-340
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    • 2018
  • The present study was to determine the effects of salinity on the growth and nutrient bioextraction abilities of Gracilaria and Ulva species, and to determine if these seaweeds can be used for nutrient bioextraction under hypo- and / or hyperosmotic conditions. Two Gracilaria species, G. chorda and G. vermiculophylla, and two Ulva species, U. prolifera and U. compressa, were cultured at various salinity conditions (5, 10, 15, 20, 30, 40, and 50 psu) for 3 weeks. Results showed that the growth rates, nutrient uptake, tissue nutrient contents and nutrient removal were significantly affected by salinity and species. All four species were euryhaline with the highest growth rates at 20 psu. Among the four species, U. prolifera, U. compressa, and G. vermiculophylla showed potential to be used for nutrient bioextraction in estuaries and / or land-based fish farms due to their rapid growth, high nutrient uptake, high tissue carbon and nitrogen accumulation and removal capacities.

Analysis of Species Composition and Communities of Phytoplankton through Marine Environmental Factors in the Coastal Water of Baegyado Island during Winter (백야도 연안의 동계 해양환경 특성에 따른 식물플랑크톤의 종조성과 군집 분석)

  • Kim, Mi-Kyung;Park, Jung-Won
    • ALGAE
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    • v.19 no.3
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    • pp.247-255
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    • 2004
  • This study was to clarify the variations in a marine ecosystem through examining the species composition of phytoplankton in the coastal water of Baegyado Island during winter. Water temperature, salinity, SS, NH$_4$-N, NO$_2$-N, NO$_3$-N and SiO$_2$-Si were significantly different and in inverse proportion to the chlorophyll a and species number according to stations and water depth. The total number of species was 88, composed of 94% Bacillariophyceae, 3.4% Chrysophyceae, 2.2% Dinophyceae and 1.1% Euglenophyceae. The dominant species were Rhizosolenia setigera, Skeletonema costatum and Stephanopyxis palmeriana. The maximum of standing crops was $5,450cells{\cdot}ml^(-1)$, while the minimum was $1,700cells{\cdot}ml^(-1)$. The coastal water was influenced with two water bodies which had characteristics of low water temperature - low salinity and high water temperature - high salinity.

Water mass and Tidal current of Karnak Bay In May-June 2004 (2004년 5-6월 가막만의 수괴분포 및 조류 특성)

  • Lee Moon-Ock;Kim Byeong-Kuk;Kim Jong-Kyu
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2004.11a
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    • pp.143-148
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    • 2004
  • In order to see physical characteristics of water masses and tidal currents in Gamak Bay, some field surveys have been conducted using ADCP, Aanderaa current meter and CTD from May 17 to June 3, 2004. The northwest of the bay appeared to have a high temperature and a high salinity so that it coincided with the previous results. The distribution of temperature and salinity seemed to reflect the characteristics of water masses. At the south mouth of the bay, a northwestward-southeastward flow was dominant at the surface layer while a northeastward-southwestward flow was dominant at the bottom layer.

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Relative Microalgal Concentration in Prydz Bay, East Antarctica during Late Austral Summer, 2006

  • Mohan, Rahul;Shukla, Sunil Kumar;Anilkumar, N.;Sudhakar, M.;Prakash, Satya;Ramesh, R.
    • ALGAE
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    • v.24 no.3
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    • pp.139-147
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    • 2009
  • Microalgae using a submersible fluorescence probe in water column (up to 100 m) were measured during the austral summer of 2006 (February) in Prydz Bay, East Antarctica (triangular-shaped embayment in the Indian sector of Southern Ocean). Concurrently, environmental parameters such as temperature, salinity and nitrogen (nitrate, ammonium, urea) uptake rates were measured. The concentration of phytoplankton is relatively high due to availability of high nutrients and low sea surface temperature. Phytoplankton community is dominated by diatoms whereas cryptophytes are in low concentration. The maximum concentration of total chlorophyll is 14.87 ${\mu}g\;L^{-1}$ and is attributed to upwelled subsurface winter water due to local wind forcing, availability of micro-nutrients and increased attenuation of photosynthetically available radiation (PAR). Concentration of blue-green algae is low compared to that of green algae because of low temperature. Comparatively high concentration of yellow substances is due to the influence of Antarctic melt-water whereas cryptophytes are low due to high salinity and mixed water column. Varied concentrations of phytoplankton at different times of Fluoroprobe measurements suggest that the coastal waters of Prydz Bay are influenced by changing sub-surface water temperature and salinity due to subsurface upwelling induced by local winds as also melting/freezing processes in late summer. The productivity is high in coastal water due to the input of macro as well as micro-nutrients.

A Study on Preference of Salinity and Temperature of Soups Served in the Institutional Foodservice Establishment (급식업체에서 제공하는 국류의 적정 염도와 온도에 관한 연구)

  • Cho, Mee-Hee;Kim, Sun-Joo;Lee, Kyung-Hee
    • Journal of the East Asian Society of Dietary Life
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    • v.18 no.4
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    • pp.601-607
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    • 2008
  • This study was examined the preferred temperature and salinity of soup in various demographic groups in order to establish the desirable serving renditions of soup for customers' satisfaction and health. Temperature and salinity were measured in August and November in order to determine the seasonal variation in preference using a digital salinity-temperature measuring device. Four demographic groups totaling 530 were from foodservice establishments in elementary schools(ES: male 68/female 59), middle-high schools(MHS: 62/69), universities(UNIV: 72/67) and companies(COM: 69/64) in Seoul. Various thin or thick soups which are typically served in foodservice establishments were served hot(below $90^{\circ}C$) and warm(below $40^{\circ}C$) in a 50mL portion: salty(1.2%) and less salty(0.4%) at $55{\pm}2^{\circ}C$. The preferred salinities and temperatures of the soups were found to be 0.74%, 0.82%, 0.64% and 0.67% and $49.65^{\circ}C$, $54.24^{\circ}C$, $57.56^{\circ}C$, $58.81^{\circ}C$ for the ES, MHS, UNIV and COM groups, respectively. The preferred temperatures of the soups were increased depending on the age, so the positive correlation was shown between temperature and age. However the preferred salinities of soups were not effected. There was no consistent tendency between men and women in temperature. For salinity, men preferred $0.04{\sim}0.12%$ higher than women in the ES, MHS and UNIV groups. There is no consistent tendency between thin and thick soup in temperature. All groups preferred higher salinity in the thick soup than in the thin soup. Most of the customers preferred a higher temperature and higher salinity in November than in August.

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Determination of Nutrient Contents and In vitro Gas Production Values of Some Legume Forages Grown in the Harran Plain Saline Soils

  • Boga, M.;Yurtseven, S.;Kilic, U.;Aydemir, S.;Polat, T.
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.6
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    • pp.825-831
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    • 2014
  • The aim of this study was to determine the nutritive value of some legume species in salt-affected soils of South-East Anatolian region using chemical composition and in vitro gas production kinetics. In this study, Lotus corniculatus, Trifolium alexandrinum, Medicago sativa were sown and tested in four different locations. A 3 by 4 factorial design with 3 legume species and 4 salt levels (non salty electrical conductivity (EC)<4 dS/m; low salt: 4 dS/m>EC<8 dS/m, medium saline: 8 dS/m>EC<16 dS/m and high salt: 16 dS/m>EC) was used in the study. Results indicated that salinity and plants had no significant effect on ash and ether extract. Dry matter (DM), acid detergent fiber, digestible dry matter, dry matter intake (DMI) were affected by plant, salinity and plant${\times}$salinity interaction. On the other hand neutral detergent fiber, relative feed value (RFV), and DMI were affected by salinity and plant${\times}$salinity interaction. Mineral contents were affected by plant species, salinity and salinity${\times}$plants interactions. In vitro gas production, their kinetics and estimated parameters such as were not affected by salinity whereas the gas production up to 48 h, organic matter digestibility, metabolizable energy (ME), and net energy lactation ($NE_L$) were affected by plant and plant${\times}$salt interaction. Generally RFVs of all species ranged from 120 to 210 and were quite satisfactory in salty conditions. Current results show that the feed value of Medicago sativa is higher compared to Lotus corniculatus and Trifolium alexandrinum.