• Journal of Wetlands Research
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• v.26 no.2
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• pp.127-138
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• 2024

The river ecosystems are influenced by numerous human activities such as agriculture and industrial operations, and benthic macroinvertebrates are utilized as important biological indicators. In this study, we aimed to assess the impact of land use surrounding rivers on river ecosystems in two industrial areas and two agricultural areas in Pyeongtaek city. We measured water temperature, dissolved oxygen (DO), and pH for physicochemical water quality assessment, and conducted water environment evaluation using benthic macroinvertebrates, cluster analysis, BMI, and ESB. Through water environment assessment, the environmental condition of rivers in agricultural areas was found to be more favorable compared to those in industrial areas. Consequently, it was observed that the impact on river ecosystems varied depending on the differences in anthropogenic activities.

• Journal of the Korean Society of Food Culture
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• v.23 no.4
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• pp.479-488
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• 2008

Some biological activities such as an electron donating capacity, the contents of total polyphenol compounds and flavonoids, fibrinolytic activity and $\alpha$-glucosidase inhibitory activity have been detected in hot water extracts of Ligularia fischeri and Angelica gigas Nakai. To increase the usefulness of the functional ingredients for prevention and improvement of some metabolic disorders, ethanol-treated hot water extracts of Angelica gigas Nakai were prepared. A hot water extract of Ligularia fischeri has 92% of electron donating capacity, 39.4 mg/g of total polyphenol compounds, 24.8 mg/g of flavonoids and 29.8% of $\alpha$-glucosidase inhibitory activity, but no fibrinolytic activity. A hot water extract of Angelica gigas Nakai has 94.7% of electron donating capacity, 5.8 mg/g of total polyphenol compounds, 2.6 mg/g of flavonoids, 0.48 plasmin units of fibrinolytic activity and no $\alpha$-glucosidase inhibitory activity. However, with partial purification using cold ethanol treatment, the $\alpha$-glucosidase inhibitory activity of Angelica gigas Nakai was increased to 70.5%. Thus, we expected a more useful effect with the use of the addition of a cold ethanol-treated Angelica gigas Nakai extract. The L, b values of cold buckwheat noodles using a mixture of 0$\sim$3% of Ligularia fischeri powder and 0.5% of an ethanol-treated hot water extract of Angelica gigas Nakai were decreased with the addition of an increasing amount of Ligularia fischeri powder. Among the mechanical qualities, only adhesiveness was significantly higher in 3% Ligularia fischeri noodles. From sensory evaluation data, it was determined that these two functional ingredients did not ruin the color, texture, and overall acceptance of the cold buckwheat noodles. A higher amount of the extracts improved the quality of the product with little added cost.

• Applied Biological Chemistry
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• v.44 no.4
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• pp.230-234
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• 2001

Traditional doenjang was fermented in different vessels, and its quality characteristics were investigated during ripening. Fermentation vessels used were dark brown glaze pot, dark brown glaze pot with glass lid and plastic box. Water content of doenjang decreased during fermentation, with doenjang pepared in dark brown glaze pot with glass lid showed the highest water content reduction. Water-soluble nitrogen content $(4.56{\sim}5.80%)$ was the highest at 8 months fermentation and amino type nitrogen content continuously increased until 12 months, with doenjang in dark brown glaze pot higher than those in plastic box. Sensory evaluation revealed the quality of doenjang fermented in plastic box was significantly lower than others after 4 months.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.2
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• pp.9-20
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• 2013

Many studies have reported additional treatment is needed to use wastewater for agricultural purpose. Economic considerations should be taken into account to establish infrastructure for agricultural reuse because of a large amount of water use in irrigation and relatively low water quality requirement. The objective of this study was to conduct economic analysis of wastewater reclamation and reuse systems for agriculture. A system dynamics approach considering complexity and dynamics in the wastewater reuse systems was used for the economic analysis, which are related with social, environmental, and economic problems. Sensitivity and benefit cost analysis for wastewater reuse systems was conducted through the established economic assessment model. The result of sensitivity analysis showed that water resources development and installation cost were the most sensitive for total benefits and costs, respectively. The scenario-based test of the organized economic assessment model shows marginal cost ranges and enables decision-makers to decide reasonable cost for the wastewater reuse systems for agriculture.

• Journal of Wetlands Research
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• v.13 no.1
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• pp.95-104
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• 2011

This study was implemented to select the suitable site for Palustrine Wetland at habitat restoration for Oriental stork, red species and top-level predator in ecosystem. The evaluation items was fitted by review the antecedent studies on the suitable site selection model and evaluation items of wetland. The study sites were setted in $5,884,800m^2$ area including Yesan-gun Dae-ree, in which Oriental stork' park will be located, through DEM(Digital Elevation Model) watershed analysis. The thematic map by valuation items with secure of water resource, soil, topography, distance between roads, houses, etc., land using, wildlife corridor, and type of water resource was prepared using GIS program. The sites with high evaluation score were selected as suitable creation sites for wetland through overlapping those maps. Total 8 sites with over 18 point were selected. The characteristics of selected sites show that the soil are consisted of clay, the connectivity is valued high with surface water, the slope are gentle, and the connectivity is good with surroundings ecosystem. The result of water quality analysis, which was implement to survey available water resources and develop the solution of problem of water environment, showed that water quality at Salmok reservoir and Bogang reservoir is generally good, but the water quality at stagnant water body rising out from groundwater is not good. This study has limit to select the suitable sites of wetland only by analyzing physiotherapy environment in study area. Hereafter, the study is need to examine closely enhancement effects of biological diversity through investigation of biotic environment.

• Korean Journal of Ecology and Environment
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• v.43 no.2
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• pp.255-262
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• 2010

This study was conducted at 5 sites of Bocheong Stream basin in May and September 2009 for the evaluate of fish assemblage and chemical water quality. For the study, the models of Index of Biological Integrity (IBI) and Qualitative Habitat Evaluation Index (QHEI) were modified as 8 and 11 metric attributes, respectively. We also analyzed patterns of chemical water quality at the sampling site over the period of 2005~2009, using the water chemistry dataset, obtained from the Ministry of Environment, Korea. The survey showed that total sampled fishes were 34 species and the most dominant species was Zacco platypus (24.3%). In Bocheong Stream basin, values of IBI averaged 28 (n=5), which is judged as a "Good". IBI score at B1, B4 and B5 indicating a "Good" condition whereas, B2 and B3 were as 21 and 22, indicating "Fair" condition, respectively. QHEI was 152 (n=5), judged as "Fair" habitat condition. Values of BOD and COD averaged 1.0 $mgL^{-1}$ (scope: 0.3~4.0 $mgL^{-1}$) and 2.3 $mgL^{-1}$ (scope: 0.3~18.7 $mgL^{-1}$), respectively. Total nitrogen (TN), total phosphorus (TP) and suspended solid (SS) were distinct spatial variation. Based on the IBI, QHEI and chemical water quality dataset, ecological health of Bocheong Stream basin was evaluated that generally good.

• Journal of the Korean GEO-environmental Society
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• v.20 no.12
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• pp.33-39
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• 2019

The upsurge of population, internal migration, economic activities and developmental works has brought significant land use and land cover (LULC) change over the period of 1990 and 2010 in the Bagmati basin of Nepal. Along with alteration on various other ecosystem services like water yield, water quality, soil loss etc. carbon sequestration is also altered. This study thus primary deals with evaluation of LULC change and its impact on the soil carbon storage for the period 1990 to 2010. For the evaluation, InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) Carbon model is used. Residential and several other infrastructural development activities were prevalent on the study period and as a result in 2010 major soil carbon reserve like forest area is decreased by 7.17% of its original coverage in 1990. This decrement has brought about a subsequent decrement of 1.39 million tons of carbon in the basin. Conversion from barren land, water bodies and built up areas to higher carbon reserve like forest and agriculture land has slightly increased soil carbon storage but still, net reduction is higher. Thus, the spatial output of the model in the form of maps is expected to help in decision making for future land use planning and for restoration policies.

• Korean Journal of Ecology and Environment
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• v.43 no.1
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• pp.24-34
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• 2010

This study was carried out to analyze some influences on ecological health conditions, threaten by various stressors such as physical, chemical and biological parameters. We collected samples in 2008 from three zones of upstream, midstream and downstream, Gap Stream. We applied multi-metric fish assessment index (MFAI), based on biotic integrity model to the three zones along with habitat evaluations based on Qualitative Habitat Evaluation Index (QHEI). We also examined fish fauna and compositions, and analyzed relations with MFAI values, QHEI values, and various guild types. Chemical parameters such as oragnic matter (BOD, COD), nutrients (TP, $NH_3$-N), coli-form number (as MPN), and suspended solids (SS) were analyzed to identify the relationship among multiple stressor effects. Using the sentinel species of Zacco platypus, the population structures and condition factors were analyzed along with DNA damages related with genotoxicant effects by comet assay. This study using all these parameters showed that stream condition was degraded along the longitudinal gradient from upstream to downstream, and the downstream, especially, was impacted by nutrient enrichment and toxicant exposure from the point source, wastewater treatment plant. Overall results indicated that our approaches applying various parameters may be used as a cause-effect technique in the stream health assessments and also used as a pre-warning tool for diagnosis of ecological degradation.

• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.678-690
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• 2020

In this study, the histological changes of Zacco platypus exposed to discharge from a Wastewater Treatment Plant (WTP), which is a point source, for a long time (2 to 3 years) were compared to the same species at a reference site (Ref.). Overall, tissues displayed various lesions in samples obtained at the point where discharge water from the point source was mixed. In the skin tissue, mucus cells from the epithelial layer expanded to the multilayered epithelium, indicating the immune system was activated. Epithelial cell detachment and proliferation were most prominent in the gills, which may have adversely affected circulation and respiration. Our data suggest immune system collapse was due to stimulation by aquatic substances. Both the fish phase analysis and the water quality analysis demonstrated depreciated conditions at the point source as compared to the reference stream, supporting the histological health evaluation results. These data together suggest a histological approach can also be used to assess water quality, and to an even higher degree when combined with other existing methods. Given the presented evaluation, improvement in the water quality of water discharged from WTP's is required.

• 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.