• Korean Journal of Environmental Agriculture
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• v.22 no.2
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• pp.79-86
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• 2003

This research was conducted to present reference data to be used as newly reclaimed tidal land management. We investigated vegetation succession at 4 reclaimed/reclaiming project areas and discussed relationship with soil and vegetation trhrough investigation and analysis soil chemical characteristics at 2 areas. 14 families 58 kinds were investigated. Vegetation were variou at Dea-Ho conservation polt and Seok-Mun National Industrial Area which are maintaining naturally. Vegetation were simple at Hong-Bo and Dongjin and MinKyong river areas which effected sea water. Common species that were investigated at 9 sites were Suaeda asparagoides, Aster tripolium, Phragmites australis, Suaeda maritima, Suaeda japonica, Carex scabrifolis. As soil desalinization progressing, soil classified at first saline-soidc soil, the nest saline soil and then normal soil. Chenopodiaceae revealed at about 30 dS/m of soil ECe and existed to 10 dS/m of soil ECe. At about 20 dS/m of soil ECe. Aster tripolium, Calamagrostis epigeios, and Sonchus brachyotus revealed and then non-halophytes and common plants at inland revealed at low soil ECe of about 10 dS/m. However it was not to progress vegetation sucdession and soil desalinization at the same time, owing to input of seeds or plants ect from out-ecosystem. So for promotion of vegetation at newly reclaimed tidal land, we proposed that it was very effective to plant artificially halophytes or suitable species through soil test.

• Journal of Environmental Impact Assessment
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• v.26 no.6
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• pp.553-562
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• 2017

In these days, agricultural reservoirs are considered as a useful resource for recreational purposes, tour and cultural amenity for vicinity communities as well as irrigation water supply. However, many of the agricultural reservoirs are showing a eutrophic or hyper-eutrophic state and high level of organic contamination. In particular, about 44.7% of the aged agricultural reservoirs that constructed before 1945 exceed the water quality criteria for irrigational water use. In addition to external loading, internal nutrient loading from bottom sediment may play an important role in the nutrient budget of the aged reservoirs. The objectives of this study were to characterize variations of thermal structure of a shallow M reservoir (mean depth 1.7 m) and examine the potential of internal nutrient loading by continuous monitoring of vertical water temperature and dissolved oxygen (DO) concentration profiles in 2015 and 2016. The effect of internal loading on the total loading of the reservoir was evaluated by mass balance analysis. Results showed that a weak thermal stratification and a strong DO stratification were developed in the shallow M Reservoir. And, dynamic temporal variation in DO was observed at the bottom of the reservoir. Persistent hypoxic conditions (DO concentrations less than 2 mg/L) were established for 87 days and 98 days in 2015 and 2016, respectively, during the no-rainy summer periods. The DO concentrations intermittently increased during several events of atmospheric temperature drop and rainfall. According to the mass balance analysis, the amount of internal $PO_4-P$ loading from sediment to the overlying water were 37.9% and 39.7% of total loading during no-rainy season in 2015 and 2016, respectively on August when algae growth is enhanced with increasing water temperature. Consequently, supply of DO to the lower layer of the reservoir could be effective countermeasure to reduce nutrient release under the condition of persistent DO depletion in the bottom of the reservoir.

• Economic and Environmental Geology
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• v.40 no.5
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• pp.587-604
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• 2007

In order to investigate the vertical variations and speciations of trace elements, and their correlations in Hoidong reservoir, sediment cores (21-41 cm below surface) and interstitial water samples were collected from five sampling locations. The total average concentrations of trace metals in sediment core samples were $232{\pm}30.8mg/kg$ for Zn, $119{\pm}272mg/kg$ for Cu, $58.4{\pm}4.1mg/kg$ for Pb, $15.7{\pm}3.3mg/kg$ for Ni and $1.6{\pm}0.3mg/kg$ for Cd. The total concentrations of trace metals in core sediments generally decreased toward the center of the Hoidong reservoir. The total concentrations of Mn, Pb and Zn decreased with depth for all the sample locations, while Cu and Fe concentrations increased. The trace metal concentrations of interstitial water sample were in the order of Fe>Mn>Cu>Zn, but Cd, Ni and Pb were not detected. The concentrations of Zn, Cu, Fe and Mn in the interstitial water samples showed a tendency of increasing toward the bottom of the core, suggesting a possible upward diffusion. This migration of trace metals may lead to their transfer to the sediment-water interface. These trace elements would be subsequently fixed onto amorphous Fe and Mn-oxides and carbonates in the topmost layer of sediment. Based on the $K_D$ values, the relative mobilities of the studied metals were in the order of Mn>Cu>Zn>Fe. Geochemical partitioning confirmed that surface enrichment by trace metals mainly resulted from a progressive increase of the concentrations in the fractions II and III. Copper, Fe, Mn and Zn concentrations of interstitial water were closely correlated with their exchangeable fractions of sediments.

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.4
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• pp.307-316
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• 2010

Complex terrain refers to irregular surface properties of the earth that influence gradients in climate, lateral transfer of materials, landscape distribution in soils properties, habitat selection of organisms, and via human preferences, the patterning in development of land use. Complex terrain of mountainous areas represents ca. 20% of the Earth's terrestrial surface; and such regions provide fresh water to at least half of humankind. Most major river systems originate in such terrain, and their resources are often associated with socio-economic competition and political disputes. The goals of the TERRECO-IRTG focus on building a bridge between ecosystem understanding in complex terrain and spatial assessments of ecosystem performance with respect to derived ecosystem services. More specifically, a coordinated assessment framework will be developed from landscape to regional scale applications to quantify trade-offs and will be applied to determine how shifts in climate and land use in complex terrain influence naturally derived ecosystem services. Within the scope of TERRECO, the abiotic and biotic studies of water yield and quality, production and biodiversity, soil processing of materials and trace gas emissions in complex terrain are merged. There is a need to quantitatively understand 1) the ecosystem services derived in regions of complex terrain, 2) the process regulation occurred to maintain those services, and 3) the sensitivities defining thresholds critical in stability of these systems. The TERRECO-IRTG is dedicated to joint study of ecosystems in complex terrain from landscape to regional scales. Our objectives are to reveal the spatial patterns in driving variables of essential ecosystem processes involved in ecosystem services of complex terrain region and hence, to evaluate the resulting ecosystem services, and further to provide new tools for understanding and managing such areas.

• Journal of Food Hygiene and Safety
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• v.25 no.4
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• pp.360-366
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• 2010

Doenjang (fermented soybean paste) is one of the korean traditional fermented soybean product which is consumed with cooked rice as a soup or paste. During the fermentation, soybean protein hydrolyzed into amino acids and various peptide, and various organic acids by mirobes related and enzymes produced by meju fermentation. Some commercial products locationally samples give more sour taste than normal due to abnormal fermentation which the reasons are not clear. Three samples that gave sour taste organoleptically were collected and analyzed their characteristics such as pH, moisture content, acidity and microbial counts. The pH of the sour sample were lower than the normal with higher acidity as pH 5.39 (normal) to pH 4.36 (S2) and 15.80 ml of(0.lN NaOH consumed) to 21.80 ml (S1) respectively. Salt and moisture contents were different with sour and normal Doenjang as 16.38% (normal) to 8.92% (S3) in salt and 55.94% (normal) to 49.34% (S1) in moisture content. Total viable counts were $4.1{\times}10^8$ (normal) to $8.0{\times}10^5$ (S2), and $3.4{\times}10^8$ (normal) to $8.0{\times}10^5$ (S2) in acid producing microbes at BCP plate. Yeast and mold were not detected. The composition of acids as mainly lactic acid and acetic acid of sour Doenjang. Total free amino acids content were lower the sour Doenjang than the normal.

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.4
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• pp.282-291
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• 2006

Effects of the molecular weight and type of chitosans on shelf-life of Makkulli were evaluated during 18 days of storage at $25^{\circ}C$. Two types of chitosans were studied: ${\alpha}$-chitosans with 11 different molecular weights (water-soluble, Mw = 1, 8, 22, 43, 67 and 616 kDa; acid-soluble, Mw = 282, 440, 746, 1,110 and 2,025 kDa) and ${\beta}$-chitosan (acid-soluble, Mw = 577 kDa). Acid-soluble chitosans were applied as a form of chitosan-ascorbate. All chitosans were added to Makkulli at 0.002% concentration, the optimum concentration established in a preliminary test. Among 12 chitosans, the ${\alpha}$-chitosans with 22 and 440 kDa exhibited stronger antimicrobial effects than did other ${\alpha}$- and ${\beta}$-chitosans. The results for pH, acidity, alcohol concentration, viable cell counts, and sensory evaluation suggested that addition of ${\alpha}$-chitosans with 22 and 440 kDa increased the shelf-life of Makkulli by almost 1 week at $25^{\circ}C$ compared with that of control (without chitosan) and other chitosan-added groups. Extension of Makkulli shelf-life by 1 week is fairly significant in view of the magnitude of the total amount of Makkulli produced in Korea.

• Journal of The Korean Association For Science Education
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• v.38 no.5
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• pp.681-691
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• 2018

The purpose of this study is to investigate the impacts of Collaborative Problem solving for Character competency (CoProC) strategy on the practical character competency and collaborative problem solving competency in middle school. For this study, 49 seventh grade students (two classes) were selected for use applying the CoProC strategy (CoProC group) while 46 students (two classes) were used for traditional lecture and experimental class (comparative group). In the result, CoProC group showed a statistically significant result in practical character competency than the comparative group. In the sub items of the competency, the CoProC group showed result statistically significant in cooperation, communication, responsibility, and positive self-understanding than the comparative group. Analysis of the effect size of students' practical character competency showed that the CoProC group results showed more effective than the comparative group in terms of care, cooperation, communication, honesty, responsibility, positive self-understanding, and self-regulation. In addition, we investigated the effect of the CoProC strategy on collaborative problem solving competency. As a result, it showed a large effect in the total score of collaborative problem solving competency. Among the sub items of the competency, 'exploration and understanding of members' showed a small size of effect and 'Establishing and maintaining team organization' showed a medium size of effect. 'Communication' and 'self-reflection' showed a large effect. CoProC strategy embedded in Science subject could improve students' collaborative problem solving competency through the process of scientific communication in the scientific inquiry process.

• Microbiology and Biotechnology Letters
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• v.38 no.1
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• pp.93-104
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• 2010

In this study, we investigated the effects of frankincense essential oil (BSEO) on the immune cell change in the lung, BALF and PBMC using a mouse model of asthma. BALB/c mice after intraperitoneal OVA sensitization (day 1) were challenged intratracheally with OVA on day 14. Then, the asthma was induced by repeated OVA inhalation challenged. The asthma induced mice group inhaled 0.3% BSEO for 30 minutes per trial, three times a week, for 8 weeks using the nebulizer. After 12 weeks from the experiment, the mice was killed and the lung, bronchoalveolar lavage fluid (BALF) and peripheral blood mononuclear cell (PBMC) were obtained. Next, the change of immune cells inside the separated tissues was observed to identity the effects of BSEO on the allergic asthma mice. In conclusion, the hypersensitive reaction of airway to the bronchoconstrictor in the allergic asthma induced mice was effectively suppressed in Frankincense group, in Bermagot, Eucalyptus, Chamomile, Marjoram and Frankincense groups, the natural aromatic essential oil groups. Furthermore, it was also confirmed that the weight of lung, total number of alveolus cells and the number of BALF, MNL and DLN increased after inducing allergic asthma were reduced. BSEO suppressed the percentage of $CD3e^+/CD19^-$, $B220^+/CD23^+$ and $CD11b^+/Gr-1^+$ cells in the lung tissue of allergic asthma mice. Moreover, BSEO also reduced the percentage of $CD4^+/CD8^-$, $B220^+/CD23^+$ and $CD3^+/CCR3^+$ cells in BALF. In addition, the percentage of $CD3e^+/CD19^-$, $CD3^+/CD69^+$ and $B220^+/CD23^+$ cells in PBMC was reduced. The results of this study indicate that BSEO would be effective to treat allergic asthma by the immune control suppressing the activity of immune cells in each tissue.

• Korean Journal of Environment and Ecology
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• v.29 no.4
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• pp.580-589
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• 2015

The artificially grown forests of larch, planted in accordance with the nationwide afforestation policy in the 1970s, are located inside national parks. This study intended to induce a forestation system by which the forests develop into an ecologically healthy and broadleaved ecosystem with broad species diversity. For this, the aspects of natural regeneration of broadleaves from 2010 to 2013 after thinning by density (30%, 50%, and 70%) in 2009 were surveyed using the larch forest in the Woljeong Temple region inside Odaesan National Park. There were no trees that were larger than 2 cm in in diameter at breast height among the trees recently introduced between 2012 and 2013. A significant number of herbs have been introduced to the subsurface alongside young arboreal trees species such as Bumalda bladdernut, Acer triflorum, Cornus controversa etc and shrubs. However, many woody species did not survive the competition with herbs and repeated withering and regeneration. The number of woody species generated within the 30% cutting area was 440 species in 2013 and this figure has been increasing twofold each year. The number of woody plants within the 50% cutting area also showed an upward tendency and most plants did not survive in the competition with herbs and Sasa borealis and withered in only 1 ~ 2 years after generation. Unlike other thinning areas, the 70% cutting area showed 608 broadleaved trees, reflecting a decrease from 748 trees in 2012. This appeared to be attributed to the luxuriance of S. borealis and the sharp increase of fatsia following the inflow of total sunlight to the forest floor. Herbs were hardly generated due to the influence of S. borealis. Regarding the density for thinning at 50% or upper height, the forest treatment division shall maintain a proper density in the course of inducing artificial forestation of larch into natural broadleaved forests considering the luxuriance of sasa borealis and herbs due to the inflow of total sunlight to the forest floor.

• Korean Journal of Environment and Ecology
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• v.23 no.1
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• pp.90-98
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• 2009

Every spring, Korea is always plagued by sandy dust from the western region of China and Mongolia. Yellow sand is causing an environmental problem to Japan and far into the American continent, let alone Korea. At present, the western region of China is going under desertification at a great speed due to climatic change and humans' damaging activities. To cope with this, each country including China is considering ecological restoration of deserts through planting. Accordingly, this research conducted a vegetation survey on Baicheng district which is a representative dry land of western China to obtain a basic data for ecological restoration of a desert. The survey revealed that Setaria viridis which invaded an arid land made a succession into Setaria viridis-Cannabis sativa var. fruderalis community together with Artemisia mongolica-Setaria viridis community due to the increase in salt concentration and alkalization subsequent to dryness. It was also found out that there finally formed Artemisia mongolica community on a flat intense in harsh wind and dryness with the continuous worsening of environmental conditions. There appeared a different type of vegetation on hilly districts where sporadic shade could come into being because the air humidity could be available relatively there. Frequently, typically appearing at the whole survey area, the Tributlus terrestris community was found to make succession into Tribulus terrestris-Cleisrogenes squarrosa community due to the aggravation of soil environment. In addition, with the worsening of the environment at hilly districts, there formed Clesirogenes squarrosa community resistant to dryness, salinity in soil and strong alkalinity. Further, there appeared higher plant life totalling to 62 taxa comprising 58 species and 4 varieties with 27 families and 49 genuses at the whole survey area. Among these, Compositae plants excellent in resistance to environment was surveyed the most, accounting for 27%.