• Korean Journal of Ecology and Environment
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• v.45 no.4
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• pp.490-498
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• 2012

This study demonstrates the investigation of zooplankton communities (e.g. rotifers, cladocerans and copepods) and environmentally related driving factors (e.g. elevation, area size, water depth, types of dike construction, and bottom substrates). We hypothesized that zooplankton community structure and composition would be influenced by ambient driving forces in different scales of the irrigation ponds (Dumbeong). A total of 66 zooplankton species/groups (56 rotifers, 9 cladocerans, 1 copepods) were found and identified at 45 Dumbeong of Goseong region (i.e. Goseong-gun) in 2011. The rotifers occupied 84.9% of the total zooplankton abundance. We could categorize a clear separation of zooplankton communities into 4 different patterns based on cluster analysis. Zooplankton diversities in Dumbeongs were lower than those in natural ponds or wetlands. In addition, community structure of zooplankton was also simpler and had a broken stick distribution based on SHE analysis. Species composition in each Dumbeong was not significantly discriminated each other. The result of canonical correspondence analysis (CCA) pinpointed that significant influential variables upon zooplankton community were dissolved oxygen percent saturation, pH, and Dumbeong's material. This study indicated that morphological type of the Dumbeong and its water quality could determine the community structure of zooplankton. Furthermore, the connectivity between ambient habitats and materials could be necessary to be rigorously considered in respect to producing the Dumbeongs to subsidize alternative habitats for wetland ecosystem in freshwater landscape.

• Journal of Marine Bioscience and Biotechnology
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• v.11 no.2
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• pp.52-61
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• 2019

Over the past few decades, microalgae-based biotechnology conjugated with innovative CRISPR/Cas9-mediated genetic engineering has been attracted much attention for the cost-effective and eco-friendly value-added compounds production. However, the discharge of reproducible living modified organism (LMO) into environmental condition potentially causes serious problem in aquatic environment, and thus it is essential to assess potential environmental risk for human health. Accordingly, in this study, we monitored discharged genetically modified microalgae (GMM) near the research complex which is located in Daejeon, South Korea. After testing samples obtained from 6 points of near streams, several green-colored microalgal colonies were detected under hygromicin-containing agar plate. By identification of selection marker genes, the GMM was not detected from all the samples. For the lab-scale environmental risk assessment of GMM, acute toxicity test using rotifer Brachionus calcyflorus was performed by feeding GMM. After feeding, there was no significant difference in mortality between WT and transformant Chlamydomonas reinhardtii. According to further analysis of horizontal transfer of green fluorescence protein (GFP)-coding gene after 24 h of incubation in synthetic freshwater, we concluded that the GFP-expressed gene not transferred into predator. However, further risk assessments and construction of standard methods including prolonged toxicity test are required for the accurate ecological risk assessment.

• Analytical Science and Technology
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• v.24 no.6
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• pp.484-492
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• 2011

Bioaccumulation status and distribution characteristics of PCDDs, PCDFs and DL-PCBs in cruian carp collected from the four representative sites of major river systems in Korea were investigated. The recovery rates of PCDDs and PCDFs ranged from 50.6% to 88.3%, and those of DL-PCBs ranged from 52.3% to 93.2%. The mean, median and concentration range of ${\sum}$dioxins, which represents the total concentratons of PCDDs, PCDFs and DL-PCBs accumulated in the muscle of crucian carp, were 0.39, 0.14 and 0.047-1.0 pg TEQ/g wet wt., respectively. DL-PCBs were detected above the detection limit from all the samples, whereas PCDDs and PCDFs were detected from limited crucian samples. The relative contribution of DL-PCBs to ${\sum}$dioxins was remarkably larger than those for PCDDs and PCDFs. The percent contribution was 83.6% for DL-PCBs, and followed by 12.7% and 3.7% for PCDFs and PCDDs, respectively.

• Korean journal of food and cookery science
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• v.11 no.4
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• pp.342-350
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• 1995

The purpose of this study was to improve and hand down traditional dining habits. Questionnaires were distributed to rural house wives in Kangwon-do. The results were as follows; 1. 30.8％ of the respondents was 40 to 49 years old. 35.2％ of their education was primary school. 49.5％ of them had husbands and children. 44.2％ of them had 3 to 4 family members. 26.9％ of them earned 8 to 11 millon won yearly. 2. Their housing environment showed that 52.5％ of housing was a Korean traditional house or Hanok. 72.1％ of kitchen was a stand-up one. 66％ of fuel was oil. 3. 99.3％ of the respondents had refrigerators. 66.3％ electronic range, 95.9％ electronic rice cooker, 97.2％ gas range, 59.6％ mixer, 62％ electronic fry pan respectively. 4. 73.5％ of the respondents got information about Korean traditional food from seniors or friends. 36.6％ of them learned new recipe from TV, newspapers and magazines. 43.3％ of them thought their concern about meals was average. 48.4％ of them paid much attention to prepare meals for themselves. 52.7％ of them spent a half to one hour for preparing dinner. 48.3% of them ate processed foodstaffs often. 31.5％ of them dined out once every two or three months. 5. 79.5％ of them had rice for breakfast, 74.5％ for lunch, and 98.4％ for dinner respectively. 96.2％ of the respondents made Kimchi and 55％ among them had two kinds of Kimchi. 91.1％ of them had two to three kinds of dishes except Kimchi for breakfast. 68％ of them used a synthetic flavoring. 6. 16.2％ of the respondents ate beef once a week, 40％ pork, 23％ chicken, 3％ dog meat respectively. 37％ of them ate mackerel pike, 25.5％ mackerel once a week, 11.6％ hairtail, 25.5％ mackerel pike, 25.6％ yeemunshu, 13.7％ tuna respectively. Freshwater fishes such as mudfish, trout and Israel carp were their favorite onces.

• Journal of Ecology and Environment
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• v.44 no.3
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• pp.185-195
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• 2020

Background: The flathead grey mullet Mugil cephalus has the widest distribution among mugilid species. Recent studies based on mitochondrial DNA sequences showed that the species comprises at least 14 different groups, three of which occur in the northwest Pacific. We analyzed the otolith microchemistry of M. cephalus at several locations in Korea to improve understanding of migration pattern and population origin. Results: We collected 123 sagittal otoliths from seven locations and determined their concentrations of eight elements (⁷Li, ²⁴Mg, ⁵⁵Mn, ⁵⁷Fe, ⁶⁰Ni, ⁶³Cu, ⁸⁸Sr, and ¹³⁸Ba) using laser ablation inductively coupled plasma mass spectrometry. Mean otolith elemental ratios differed significantly among the locations. The Sr:Ca, Fe:Ca, and Ba:Ca ratios were significantly higher than others, and useful chemical signatures for investigating the habitat use of M. cephalus populations. We identified five diverse and complicated migration patterns using the otolith data that we collected: estuarine resident (type I), freshwater migrant (type II), estuarine migrant (type III), seawater resident (type IV), and seawater migrant (type V). A canonical discriminant analysis plot revealed separation of two groups (type II in the Yellow Sea vs. other types in remaining locations). Two locations on Jeju Island, despite their close proximity, had fish with quite different migration patterns, corroborating previous molecular studies that distinguished two groups of fishes. Conclusion: We successfully showed that the migration patterns of the Korean mullet varied by location. Only fish from the western sector of Jeju had a unique migration pattern, which is likely confined population in this area. Among the eight otolith elements measured, the Sr:Ca ratio was found to be the best indicator of migration pattern and population origin.

• Ocean and Polar Research
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• v.29 no.3
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• pp.273-282
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• 2007

For an efficient management and utilization of marine biodiversity information, we made an attempt to develop the Korea Marine Biodiversity Information System (KoMBIS), building a species name inventory of Korea marine organisms. The inventory includes 17 organism groups: phytoplankton, zooplankton, algae and halophyte, sponges, cnidarians, rotifers, nematodes, bryozoans, brachiopods, molluscs, echiurans, annelids, arthropods, echinoderms, urochordates and fish. The species names were collected from 37 different references and reviewed for validity by taxonomists, which resulted in 9,798 valid names in addition to 1,845 synonyms. The Korea marine species inventory is the first one of this kind, for previous Korean species name inventories were mostly composed of terrestrial and freshwater organisms. KoMBIS, the information system developed, contains not only the species name but also information on morphological and ecological characteristics such as distribution, DNA barcode, and references. This system is convenient for the inputting of new data and servicing users through the internet, so that management and utilization of the biodiversity information is more efficient. Linking the DNA barcode data with species information provides an objective measure for identification of a species, which accommodates the recommendation of Consortium for the Barcode of Life, and makes the Korea marine biodiversity information compatible with international databases. Considering the frequent exchange of marine organisms internationally via ballast water and such issues as climate change, this information system will be useful in many areas of marine biodiversity.

• Journal of Applied Biological Chemistry
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• v.59 no.1
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• pp.83-90
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• 2016

The aim of the present study was to evaluate the degree of metal contamination of the Turag River water and its suitability for irrigation. Twenty water samples were analyzed for physicochemical parameters and metals viz., calcium, magnesium, potassium (K), sodium, copper (Cu), zinc (Zn), iron (Fe), manganese (Mn), lead (Pb), cadmium (Cd), chromium (Cr), and nickel (Ni). All water samples were slightly alkaline to alkaline. Regarding electrical conductivity (EC), all samples were suitable for crop in soils with moderate permeability and leaching. Water samples were medium salinity and low alkalinity hazard classes. In terms of total dissolved solids (TDS), all samples were classified as freshwater. As per sodium adsorption ratio (SAR) and soluble sodium percentage (SSP), all samples were classified as excellent. No residual sodium carbonate (RSC) was detected in any of the samples, indicating suitability for irrigation; and all samples were considered very hard. Cr and Mn contents in all samples were above FAO guideline values and, therefore, these metals were considered toxic. Zn, Cu, Pb, Cd, and Ni concentrations were below acceptable limit for irrigation and do not pose a threat to soil environment. Significant relationships were found between EC and TDS, SAR and SSP, SAR and RSC, and SSP and RSC. The combinations of ions such as K-Zn, K-Fe, K-Cu, K-Mn, K-Pb, Zn-Fe, Zn-Cu, Zn-Mn, Fe-Mn, Cu-Mn, Cu-Pb and Mn-Pb exhibited significant correlation. This study revealed that Turag River water samples are contaminated with Cr and Mn. This fact should not be ignored because water contamination by metals may pose a threat to human health through food chain.

• The Korean Journal of Quaternary Research
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• v.13 no.1
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• pp.1-23
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• 1999

A palynological investigation of the Annyeong-ri, Hwasung-gun Gyeonggi-do, in where Yung-Nung and Gun-Nung are located, was carried out for the first time. From the pollen analysis, two pollen zones are established: Pollen Zone I : Ainus-Quercus-Pinus and Pollen Zone Ⅱ : Pinus. Pollen Zone I is characterized by Mixed coniferous and deciduous broadleaved vegetation during about 3,500 yr. B.P.-2,000 yr. B.P., while after 2,000 yr. B.P. Pollen Zone Ⅱ appears to be Coniferous vegetation and Evergreen broadleaved vegetation. The former reflects there was a lowland fluvio-lacustrine environment before fully lacustrine one which represents the latter. Pollen analysis indicates the vegetation before 2,000 yr. B.P. was controled by environmental factor such as climate conditions, whereas after that time vegetation was strongly effected by human's impact. It is concluded that pollen analysis is useful to find out the relationship between vegetation history and man's interference. In addition freshwater algae play to tell the lake environments.

• Journal of Ecology and Environment
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• v.38 no.3
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• pp.383-388
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• 2015

Reservoirs consist of two different environments, the littoral and the pelagic zone, and different fishing gear is commonly used in each zone-gill nets in the pelagic zone and electrofishing in the littoral zone. However, an active fishing gear, the cast net, is normally used instead of electrofishing for scientific studies in South Korea. In order to estimate cast net effectiveness for determining fish status in reservoirs, the study was conducted at 15 reservoirs with two different fishing gears: a cast net in the littoral zone and gill nets in the pelagic zone. When combining catches of both gears, species richness increased substantially compared to using one gear only. There was a size difference in fish caught by each net, and small fish were predominantly caught with the cast net due to its small mesh size (7 mm). The combined length of six species, used for length-weight relationship analysis, collected with the cast net was smaller than that collected with gill nets (independent t-test, P < 0.05). In this study, cast net sampling provided sufficient data for the littoral zone, but not enough to identify the overall fish assemblage in studied reservoirs. Utilization of only one gear can therefore lead to substantial underestimation of fish status, and a combination of both gears is recommended for determining more reliable estimates of fish status in reservoirs.

• Journal of Ecology and Environment
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• v.38 no.3
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• pp.375-381
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• 2015

We investigated the influence of summer rainfall on Pectinatella magnifica colonies in lotic ecosystems. Of the examined substrate materials, branches and aquatic macrophytes supported more colonies of P. magnifica than that by stones or artificial materials. The influence of rainfall on P. magnifica colonies differed in accordance with the type of substrate material at each study site. In the Geum River, little difference was noted in the number of P. magnifica colonies on branches before ($mean{\pm}SE$, $24{\pm}7.3$ individuals) and after rainfall ($20{\pm}8.4$ ind.); other substrate types supported fewer colonies of P. magnifica after rainfall. In contrast, in the Miryang River, rainfall had minimal effect on the number of P. magnifica colonies supported by macrophytes ($13{\pm}3.8$ and $12{\pm}4.3$ ind., respectively). Artificial material was more abundant in the Banbyeon Stream where it was able to support more colonies of P. magnifica. We found that the structure of different substrates sustains P. magnifica following rainfall. In the Miryang River, free-floating and submerged plants with a relatively heterogeneous substrate surface were the dominant macrophytes, whereas in the Geum River, simple macrophytes (i.e., emergent plants) were dominant. Therefore, we conclude that the substrate type on which P. magnifica grows plays an important role in resisting physical disturbances such as rainfall.