• Title/Summary/Keyword: Salinity difference

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Distributional characteristics of mesozooplankton community in Nakdong river estuary (낙동강 하구역의 동물플랑크톤 군집 분포특성)

  • Kang, Jung-Hoon;Kim, Minju
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.7
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    • pp.1-11
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    • 2020
  • This study investigated the mesozooplankton community and the related environmental factors in the Nakdong River Estuary in May and early October shortly after passage of the typhoon "DUJUAN" in 2015. The mesozooplankton community was dominated by barnacle nauplii, foraminiferans, and Noctiluca scintillans, and the environmental characteristics were characterized by freshwater inflow through the Nakdong River barrage, the intrusion of warm currents, and the effect of typhoon passage in October. In May, cladocerans, such as Evadne nordmanni and Podon polyphemoides, as indicator species of brackish water, prevailed throughout the study area. The surface salinity was lowest on the inner side of the barrier-islands and increased gradually to the outer side during the study. The average concentration of total suspended solids in October was higher than that in May, while the averaged concentration of nitrate and chlorophyll-a in May was higher than those in October. On the other hand, there was no temporal difference in the total averaged abundance of mesozooplankton. In contrast, the distributional pattern of the mesozooplankton community was associated with the salinity gradient in both seasons. These results suggest that the temporal difference of the mesozooplankton community depended on the extent of freshwater inflow by barrage opening, the intrusion intensity of warm currents, and typhoon passage in the Nakdong River estuary in 2015.

Seasonal Characteristics of Temperature and Salinity Variations Around the Tongyeong and Geoje Coastal Waters by a Cluster Analysis (군집분석을 이용한 통영·거제 연안역의 수온·염분 계절 변동 특성)

  • Kim, Byeong Kuk;Lee, Chang Rae;Lee, Moon Ock;Kim, Jong Kyu
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.19 no.3
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    • pp.173-184
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    • 2016
  • This study was carried out to understand the characteristic distributions of water temperature and salinity in accordance with seasons atound the Tongyeong and Geoje, based on a cluster analysis. Water temperatures in coastal areas were $1-2^{\circ}C$ higher than those in open seas when in the spring, autumn and winter. In particular, a south-northward isothermal line was established at the bottom layer in the winter of 2014, unlikely to the surface layer. In addition, a south-northward isohaline was also established at the bottom layer in the winter of 2013. Therefore, we recognized that a moving pattern of water masses has also a difference since forming directions of those lines were not equivalent with each other between the surface and bottom layers. In contrast, stratification appeared in the summer with a roughly difference of water temperature of $10^{\circ}C$ and a salinity of 2-10 psu between the layers. A cluster analysis indicated that the southeastern coastal waters have three distinct water masses, even though some complicated situations exist due to the seawater inflow from the outside. However, the result of a cluster analysis turned out quite reasonable because the result of a regression analysis proved that it is appropriate, just except for the timing of a south-northward front formation.

Quality Characteristics of Tomato Sauce added with Various Thickening Agent (농후제를 달리한 토마토소스의 품질 특성)

  • Kim, Young-Jun;Kim, Ki-bbeum;Park, Ki-hong;Choi, Soo-keun
    • Culinary science and hospitality research
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    • v.22 no.7
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    • pp.100-111
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    • 2016
  • Tomato sauce were prepared with five different thickening agents including roux (TR), non-glutinous rice powder (TN), glutinous rice powder (TG), potato starch (TP) and tapioca starch (TT) to examine proximate composition (moisture, carbohydrate, crude protein, crude fat, crude ash, crude ash), calorie, color value, pH, salinity, $^{\circ}Brix$, reducing sugar, viscosity and sensory test (attribute difference, acceptance). The results were as follows: Moisture, carbohydrate content were the lowest while crude fat and calorie were the highest in TR (roux). On the other hand, moisture, carbohydrate content were the highest while crude protein, crude fat and calorie were the lowest in TP (potato starch) and TT (tapioca starch). Using potato starch and tapioca starch are supposed to be prepared low-fat, low-calorie tomato sauce. L value was the highest in TN (non-glutinous rice powder), a value was the highest in TP (potato starch), b values was the highest in TR (roux). pH of tomato sauce showed a range of 5.24 to 5.39. TG (glutinous rice powder) was the highest and TT (tapioca starch) was the lowest in pH. TP (potato starch) was the highest salinity, reducing sugar was the lowest. TG (glutinous rice powder) was the lowest salinity, $^{\circ}Brix$ was the highest. And TR (roux) was the lowest $^{\circ}Brix$, reducing sugar was the highest. In viscosity, TG (glutinous rice powder) was the highest and TT (tapioca starch) was the lowest. The attribute difference test results was the highest in gloss, color intensity, tomato odor, tomato taste, pure taste in TT (tapioca starch) and savory taste, oily taste, thickness, residue was the highest in TR (roux). The preference test results reveal that the appearance, flavor, taste, texture and overall acceptance level was the highest in TP (potato starch) and TT (tapioca starch). The results of this study, tomato sauce prepared potato starch and tapioca starch instead of the traditional roux was higher in sensory acceptability. Recently, people is avoided high-fat and high-calorie foods, and potato starch and tapioca starch are confirmed that the tomato sauce can be made of a low-fat and low-calorie.

Uncertainty Analysis of the Net Flow Discharge and Diffusion Model in Gyeonggi Bay and Han River Estuary (경기만 및 한강하구의 순유량 및 확산모형의 불확실성 분석)

  • Kim, Jeong-Dae;Jeong, Shin-Taek;Cho, Hong-Yeon;Kim, Tae-Heon
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.22 no.5
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    • pp.344-351
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    • 2010
  • Uncertainty analysis on the net flow discharge (NFD) influencing the long-term material transport and the simulation results of the salinity and COD concentration distribution using the MIKE21 diffusion model in Gyeonggi bay and Han-River estuary is carried out. The NFD flowing the Gyodongdo - Seokmodo channel via the North channel of Ganghwado is estimated about 97% of the total NFD and the NFD of the Yeomha channel is estimated as only $2.5{\sim}3.0%$. On the other hand, the uncertainty defined as the difference by the different time-scale data input is analysed by the comparison of the model simulation result of the salinity and COD concentration distribution. One is computed based on the daily river flow data, and the other is computed based on the monthlymean river flow data. The results show that the salinity and COD concentration differences are about -10~20 psu and ${\pm}1.0\;mg/L$ during the summer season having a high flow discharge in Yeomha channel, respectively. The difference is clearly negligible in the open sea area.

Change Pattern Analysis of the Salinity, 55 and DO Concentrations in Jumunjin Harbour, Gangneung (강릉 주문진항 염도, 탁도 및 응존산소 농도 변화양상 분석)

  • Cho, Hong-Yeon;Kim, Chang-Il;Lee, Dal-Soo;Han, Dong-Jun
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.19 no.4
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    • pp.385-398
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    • 2007
  • It was analysed that spatial and temporal change patterns of general water quality constituents were measured monthly from 2002 to 2005 in Jumunjin Harbour. The measured constituents are temperature, salinity, pH, SS and DO. Concentration difference of upper lower layer for general water quality constituents was small. Temperature and DO concentration show the clear difference at temporal concentration change pattern, but SS, pH and salinity have irregular change pattern. Also, water quality improvement effect of seawater exchange facilities and sewage treatment plants is analysed quantitatively using averaged spatial and temporal data set. From this result, it is found that effect of sewage treatment plants is small and seawater exchange facilities at zone 1 and 2 is clear concentration reduction effect to be about 26% and 16%, respectively. After sewage treatment plants operation, DO concentration reduced about 10% at inner zone of Jumunjin Harbour, the other side, after seawater exchange facilities concentration DO concentration increased about 10%. DO concentration at 2005 estimated little than that of 2002, it is concluded that a yearly change of DO concentration has about 10%.

Studies on the Manufacturing and Fermentation Characteristics of Soy-Sauce-Kimchi (장김치의 제조 및 발효특성에 관한 연구)

  • Kim, Eun-Jung;Hahn, Young-Sook
    • Korean journal of food and cookery science
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    • v.24 no.4
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    • pp.517-524
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    • 2008
  • This study made Soy-Sauce-Kimchi and investigated its pH, acidity, microorganism, salinity, chromaticity, viscosity and taste to revive traditional Soy-Sauce-Kimchi using Soy-Sauce instead of salt and to report its fermentation characteristics. As one of studies on traditional Kimchi, it tried for practical use of traditional Soy-Sauce-Kimchi which had been eaten in the middle region of Korea, especially in Seoul but currently has been prepared by only a few people and has disappeared gradually. According to the results of this study, among three groups of Soy-Sauce-Kimchi-I(s1), Soy- Sauce-Kimchi-II(s2) added by 2.5% sucrose and the control group(C), acidity of s2 was sharply increased after 24 hours and 72 hours at $20^{\circ}C$ and $10^{\circ}C$ respectively and there was few difference in salinity by temperature. In the case of s2 group, addition of 2.5% sucrose was considered to lead to increase of salinity. For chromaticity, while the L value and b value became larger after 48 hours, the a value tended to decline. Viscosity of s2 grew after 24 hours at all of $20^{\circ}C$, $10^{\circ}C$ and $1^{\circ}C$ and that was thought to be because propagation of bacteria such as Leuconostoc mesenteriodes following addition of 2.5% sucrose secreted dextransucrose so sucrose was transferred into dextran to increase viscosity. The total number of microorganisms was recorded to be largest after 48, 36 and 72 hours at $20^{\circ}C$, $10^{\circ}C$ and $1^{\circ}C$ respectively and the number of lactic acid bacteria was the largest at $1^{\circ}C$ after 72 hours compared to those at other temperatures. That was considered to be because microorganisms such as Leuconostoc mesenteriodes are psychrotropic lactic acid bacteria. For sensory evaluation, all appearance, chromaticity and odor of C were higher by $3{\sim}4$ points than those of s1 and s2(p < 0.001) and their feel also showed a similar tendency(p < 0.05). Considering the results of sensory evaluation, more researches were needed to overcome difference of taste for Soy-Sauce-Kimchi according to age due to characteristic flavor and smell of soy-source.

Water Quality Modeling of the Ara Canal, Using EFDC-WASP Model in Series (3차원 EFDC-WASP 연계모델을 이용한 경인아라뱃길 수질 예측)

  • Yin, Zhenhao;Seo, Dongil
    • Journal of Korean Society of Environmental Engineers
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    • v.35 no.2
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    • pp.101-108
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    • 2013
  • Ara Canal is the first artificial canal in Korea that connects the Han River and the Yellow Sea. Due to mixture of waters with different salinity and water quality, complicated hydrodynamic and water quality distributions are expected to occur inside the canal. An integrated hydrodynamic and water quality modeling system was developed using the 3 dimensional hydrodynamic model, EFDC (Environmental Fluid Dynamics Code) and the water quality model WASP (Water Quality Analysis and Simulation Program). According to the modeling results, BOD, TN, TP and Chl-a concentrations inside the canal were lower at the West Gate side than the Han River side since influent concentrations of the West Gate side are significantly lower. Chemical stratification due to salinity difference were more evident at the West Gate side as vertical salinity difference were more pronounced in this area. On the other hand, Chl-a concentrations showed more pronounced vertical distribution at the Han River side as Chl-a concentrations were higher in this area. It was notable that Dissolved Oxygen concentrations can be lower than 2 mg/L occasionally in the middle part of the canal. While major factor affecting DO concentrations in the canal are inflows via both gates, the other important factor was found to be BOD decay in the canal due to extended hydraulic residence time. This study can be used to predict hydrodynamic conditions and water quality in the canal during the year and thus can be helpful in the development of gate operation method of the canal.

Quality Characteristics of baechu Kimchi Salted with Recycled Wastebrine (재활용 절임수로 제조한 배추 김치의 특성)

  • 윤혜현;이숙영
    • Korean journal of food and cookery science
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    • v.19 no.5
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    • pp.609-615
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    • 2003
  • In the Kimchi manufacturing industry, the process of brining baechu produces a vast amount of high salinity waste water. To study if this brine can be recycled, the quality characteristics of Kimchi salted by waste brine(F), which was used five times successively, was compared with those salted using water after recycling filtration through sand (F1) and activated carbon (F2) columns. No significant difference in the salinity and soluble solid contents, during fermentation at 10 was observed among the samples, but the salinity and soluble solid contents of the F-sample were slightly higher than in the control. The F1 and control Kimchi showed similar pHs and titratable acidities, while the F-Kimchi had a lower pH and a higher acidity during fermentation. The numbers of total viable cells were highest in the F, and lowest in the F2-Kimchi, while the counts of lactic acid bacteria were lowest in the F-Kimchi. The sensory tests for appearance, odor, taste and overall acceptance showed that the F-Kimchi was the least desirable, the F2-Kimchi had lower sour odor and taste, and a higher toughness, than the others. The F1- and control Kimchi had similar sensory grades for appearance, odor, and tastes, and there were no significant difference in the overall acceptance, showing the possibility of recycling wastewaters as brine for the production of baechu Kimchi.

Phytoplankton and Environmental Factors in Lake Hwaong (화옹호의 식물플랑크톤과 환경요인)

  • Chung, Mi-Hee;Kim, Ho-Sub;Choi, Chung-Il;Hwang, Soon-Jin
    • Korean Journal of Ecology and Environment
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    • v.37 no.2 s.107
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    • pp.193-204
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    • 2004
  • This study was conducted to evaluate both temporal and spatial dynamics of phytoplankton community and environmental parameters in a newly made reclaimed esturine lake (L. Hwaong). Monthly sampling was conducted at 4 sites covering the longest transect of longitudinal gradient of the lake from June to November, 2002. Total 5 classes 8 orders 26 families 83 genus 192 species were identified at all study sites during the study period. Phytoplankton total cell density ranged 24${\sim}$ 1,882 cells $mL^{-1}$ and highly varied both temporally and spatially. Total cell density was significantly related with salinity, pH, BOD, COD, SS, TN and TP concentration. Diatom density also was significantly correlated with salinity, SS, BOD, COD and TN concentration, Although there was spatial difference, a longtudinal gradient appeared in phytoplankton cell density, Chl-a, TN and TP concentration from the mouth of river in June and August. In conclusion, phytoplakton community structure was dominated by diatoms (Bacillariophyceae), and appeared to be largely influenced by salinity, precipitation, and nutrients during the summer and the fall.

Quality Characteristics of Brown Sauce Made with Freeze-dried Salicornia herbacea L. Powder (함초를 이용한 브라운소스에 관한 품질특성)

  • Kim, Ja-Kyoung;Yoo, Seung-Seok
    • Culinary science and hospitality research
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    • v.18 no.5
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    • pp.243-255
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    • 2012
  • This research has been conducted to develop the best recipe for brown sauce containing freeze-dried Salicornia powder. For this purpose, we made brown sauces with different contents of freeze-dried Salicornia powder and performed physico-chemical characteristic and sensory test. The highest salinity of freeze-dried Salicornia powder was 0.15% when 1% freeze-dried Salicornia powder was added to distilled water, SP1. The highest brightness of brown sauce was achieved with 1.2% freeze-dried Salicornia powder and was 45.29 with BSP12. More powder led to significant increases of the samples(p<0.001) in salinity and brightness. DPPH radical scavenging increased with greater freeze-dried Salicornia powder. Taste was highest at 6.36 with 0.6% powder and there was no significant difference compared to BSP6 and BSP9. Based on these findings, it was concluded that the brown sauce with Salicornia has antioxidative characteristics and the best salinity is achieved with 0.6% freeze-dried Salicornia powder. Salicornia had enough salinity to substitute salt to a certain degree and improved the quality of brown sauce in terms of the sensory test.

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