• Journal of Environmental Impact Assessment
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• v.8 no.1
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• pp.107-120
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• 1999

This study was performed to survey the general feature of reservoir sediment in Daecheong, Sapkyo and Kumkang reservoir. For investigations, sediments were sampled at four sites in Dae-Cheong and two sites in SapKyo and Kumkang in June and October. The items for investigation are as follows; water content, loss on ignition(IG), porosity of sediment, contents of element such as hydrogen, nitrogen, carbon, phosphorus contents and nutrient release rates. Loss on ignition was measured to determine the contents of organic substance. And its ranges were determined 2.4~16.2% in Daecheong reservoir, 5.6~27.9% in Sapkyo and 4.8~18.7% in Kumkang reservoir. And, total phosphorus contents in sediments were measured $677{\sim}5,238{\mu}g/g$ in Daecheong, $780{\sim}1,417{\mu}g/g$ in Sapkyo and $604{\sim}1,452{\mu}g/g$ in Kumkang reservoir. And release rates of nutrients were calculated $0.05{\sim}8.63mgP/m^2day$ and $4.99{\sim}36.56mgN/m^2day$ in Daecheong, $1.83{\times}10^{-3}{\sim}3.23{\times}10^{-2}mgP/m^2day$ and $1.97{\sim}.22mgN/m^2day$ in Sapkyo, $8.31{\times}10^{-3}{\sim}6.51{\times}10^{-2}mgP/m^2day$ and $0.89{\sim}4.42mgN/m^2day$ in Kumkang reservoir, respectively. And this study attempted to determine the humus level of sediments. As a result of elemental analysis, C/N ratio was determined 3.0~13.1 in Daecheong reservoir, 6.5~13.0 in Sapkyo and 3.6~12.6 in Kumkang reservoir, respectively. From the elemental analysis, humus levels of reservoirs were changed from mesohumic to oligohumic state in all reservoirs.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.4
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• pp.726-732
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• 1997

The purpose of this study is to develop a software program to diagnose and assess status of dietary intake obtained using 24-hour dietary recall method. This program consist of four functions. The first function is assessing tile general status of the body such as ideal body weight, obesity measure, activity expenditure energy and total energy requirement by the analysis of age, height, weight and the degree of activity. The second one is calculating the intake number of food classified by the food group and evaluating the status of food intake by comparing them with the number of standardized intake in recommended dietary allowances for Koreans,6th revision. Third one is calculating energy and nutrient intakes contributed by the food group in dietary intake and evaluating the status of dietary intake by comparing the nutrient intake with the recommended dietary allowance for Korean, especially calculating and evaluating the status of dietary fat intake. The fourth function is calculating and evaluating the status of nutrient intake and nutrients energy Percent contributed by three regular meals and at least one in-between-meal snack. The results are displayed as tabular forms and graphical forms on the computer screen.

• Journal of Plant Biotechnology
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• v.45 no.4
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• pp.289-298
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• 2018

The Biosafety Division of the National Academy of Agricultural Science has developed a 'Crop Composition DB' that provides analytical data on commercialized crops. It can be used as a reference in the 'Comparative Evaluation by Compositional Analysis' for the safety assessment of genetically modified (GM) crops. This database provides the composition of crops cultivated in Korea, and thus upgrades the data to check the extent of changes in the compositional content depending on the cultivated area, varieties and year. The database is a compilation of data on the antioxidant, nutrient and secondary metabolite compositions of rice and capsicum grown in two or more cultivation areas for a period of more than two years. Data analysis was conducted under the guidelines of the Association of Official Analytical Chemists or methods previously reported on papers. The data was provided as average, minimum and maximum values to assess whether the statistical differences between the GM crops and comparative non-GM crops fall within the biological differences or tolerances of the existing commercial crops. The Crop Composition DB is an open-access source and is easy to access based on the query selected by the user. Moreover, functional ingredients of colored crops, such as potatoes, sweet potatoes and cauliflowers, were provided so that food information can be used and utilized by general consumers. This paper introduces the feature and usage of 'Crop Composition DB', which is a valuable tool for characterizing the composition of conventional crops.

• Journal of Environmental Impact Assessment
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• v.28 no.3
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• pp.215-230
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• 2019

The objective of this research is to evaluate the water quality characteristics using the statistical analysis of major tributaries in the Han River and to provide water quality improvement plan by selecting tributaries that should be preferentially managed by river grade classification method. The major 15 tributaries in Han River watershed were monitored for discharge and water quality during January-December 2017. As a result of the correlation analysis, the river discharge has been not correlation with other water quality constituents (p>0.05) but COD and TOC were significantly correlated (r=0.957, p<0.01). The main cause of water quality fluctuation was organic pollutants and nutrients in the principal component analysis (PCA) method. The BOD, COD, TOC, TN, and TP were found to be significantly different (p<0.05) by seasonal in result of one-way ANOVA analysis. Result of river grade classification by quantitative indicators the tributaries requiring improvement of water quality were Gulpocheon, Anyangcheon, Wangsukcheon, and Tancheon which affected by wastewater treatment plant.In this research, we determined tributaries that need to improve the water quality of Han River watershed and it can be used as an important data for efficient water quality management.

• The Journal of the Korea Contents Association
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• v.22 no.6
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• pp.580-595
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• 2022

This study looked at the relationship between lifestyle choices and various substance addictions in young adults by applying the Relapse Prevention model of addiction. The data was obtained from a cross-sectional questionnaire (Depression and Anxiety Assessment Test) of 926 young adults aged 18~24 from 24 countries. Of these, 17.6% reported that they had a serious substance addiction, with alcohol addiction being the highest (11.2%), followed by nicotine (10.3%) and illicit drug (8.7%) usage. Results of chi-square test and logistic regression analysis revealed a significant association between various lifestyle factors (exercise patterns, intake of dietary nutrients like tryptophan, folic acid, omega-3 fatty acids and micronutrients, spiritual habits such as Bible reading and prayer) and addiction to various substances (illicit drugs, alcohol and nicotine). Depression was also found to be a significant factor influencing substance addiction. Interestingly, the risk of alcohol abuse was the highest at 9.870 (95% CI: 4.525-21.525) times among those who didn't have the habit of daily Bible reading. The highest risk of nicotine and illicit drug addiction was among those who consumed 'less than 1 serving' of dietary micronutrients per day compared to those who consumed '5 or more servings', with odds ratios of 9.606(95% CI: 2.726-30.111) and 8.642(95% CI: 2.022-37.378), respectively. These findings suggest that holistic lifestyle interventions may help prevent and reduce substance addiction in young adults.

• Journal of Environmental Impact Assessment
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• v.32 no.5
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• pp.291-304
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• 2023

Harmful algal blooms (HABs) have become an increasing concern in terms of human health risks as well as aesthetic impairment due to their toxicity. The reduction of water pollutants, especially nutrients from non-point sources in a reservoir watershed, is fundamental for HABs prevention. We investigated the pollutant removal efficiencies of a constructed wetland to evaluate its feasibility as a method for controlling non-point sources located in the Annaecheon stream within the Daecheong Reservoir watershed. The overall removal efficiencies of pollutants were as follows: BOD 14.3%, COD 17.9%, SS 50.0%, T-N 19.0%, and T-P 35.4%. These results indicate that constructed wetlands are effective in controlling pollutants from non-point sources. The seasonal variation in removal efficiency depended on the specific pollutants. The removal efficiencies of BOD, COD, and T-N were stable throughout the year, except during winter, which might have been influenced by lower microorganism activity. In contrast, T-P showed a consistent removal efficiency even during the winter season, suggesting that the wetland can reduce external phosphorus loading to the reservoir. Regarding the effects of pollutant loadings on removal efficiency, the effluent concentrations of all pollutants were significantly decreased compared to those in the influent in case of middle and high loadings. This demonstrates that constructed wetlands can handle high pollutant loads, including the initial runoff during rainfall, to prevent reservoir eutrophication. Despite the various strengths of wetland water purification, there are limitations as passive treatment. Therefore, more case studies should be conducted to suggest optimum operational conditions for constructed wetlands, taking into consideration reservoir-specific characteristics.

• Korean Journal of Ecology and Environment
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• v.33 no.1 s.89
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• pp.51-60
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• 2000

In order to understand the trend and assessment of water pollution, seasonal water quality was determined in the main river and the tributaries from midstream to downstream of the Kum River from March 1998 to June 1999. Among environmental factors, the variation of nitrogen, phosphorus and chlorophyll-a was distinctive on an aspect of increase and decrease relatively to others, and particularly the impact of inorganic N ${\cdot}$ P inflowing into the main river was observed to be more significant at the Kapchon, Mihochon and Soksongchon among the tributaries. Water quality was highly related to hydrologic factor, and it was more deteriorated when water discharge maintains for a long time below normal flow or relatively at low condition of minimum and drought flow. These phenomena were remarkablee from December to March of the next year. $NH_4$ and SRP were decreased dramatically flowing toward the lower part of the river and chl-a was increased exponentially. While, the variations of $NO_3$ and $BOD_5$ were regular from midstream to downstream and there was no significant difference between the stations. Limiting nutrient for Phytoplankton growth seemed to be P than N because the ratio of TN/TP or DIN/SRP was relatively high as 42 or 544 in the main river, respectively. The main river and tributaries were ranked to be third grade, based on the assessment of BOD as an indirect indicator of organics, but particularly Kapchon was ranked to be over fifth grade. In addition, the inflow of high N ${\cdot}$ P nutrients from tributaries including Kapchon and Mihochon seemed to be major factor of the development of water pollution of the Kum River. On the other hand, persistent bloom of phytoplankton in lower part of the river was observed. As a conclusion, management of water quality for main source of pollution is urgent.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.2
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• pp.162-169
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• 1998

This study was carried out to assess the roles of soil and vegetation on the nutrient cycling in paddy ecosystem where excessive amounts of animal wastes were flowed in due to the rain. Experimental sites included one abandoned and four cropping paddy fields which were moderately terraced under a small farm village raising 90 milk cows and 35 deer under open-air condition. The watershed covered 4 ha with every 50% of uptown and fodder crops. Concentrations of $NH_4-N$ and $P_2O_5$ in waste water flowed into the abandoned paddy field, enforced by the rain of $56.4mm\;day^{-1}$, were $8.3mg\;{\ell}^{-1}$ and $1.8mg\;{\ell}^{-1}$, respectively. Total mass of rainfall inflow to abandoned field during rice growing period (1 May to 30 Sept.) was $20,900Mg\;ha^{-1}$. Total amounts of $NH_4-N$ and $P_2O_5$ contained in that inflow were estimated as 173 kg and 38 kg, respectively. Concentrations in the outflow water through one abandoned and four rice paddy fields were reduced by 92% for $NH_4-N$ and 95% for $P_2O_5$, as compared to those in the inflows. The reserved portions of nutrients in the abandoned paddy field ecosystem, which were the summation of the uptake by weed and residues in soil, were 29% of the inflow amount for $NH_4-N$ and 30% for $P_2O_5$. These results demonstrated that soil and vegetation in paddy field ecosystem reduced the excessive nutrients from the animal waste inflow to the extents that might be suitable not only for the better growth of rice plant, located at the lower paddy fields, but also for preservation of the downstream from eutrophication.

• Korean Journal of Ecology and Environment
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• v.36 no.1 s.102
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• pp.38-47
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• 2003

The water quality of the Pyeongtaek Reservoir and its main streams has been eval uated far water pollution state in March, June, September and December,2000. The following are the findings: $NH_4$ accounts for the majority of TN in the inflow streams. In the reservoir, TN and $NH_4$ are the more present in the winter season and less in the summer season, with $1.6{\sim}2.4$ times of $NO_3$ and $5.3{\sim}11.4$ times of $NO_2$ found in December and June compared with other seasons. The concentration of each component is different between streams: $NH_4$ among inorganic nitrogen has the highest concentration in the upstream, and $NO_3$ is more prevalent in the downstream. SRP accounts for $25{\sim}69%$ of TP in the stream. Unlike N component, P component in the reservoir rapidly decreases from upstream toward downstream, except in the summer. Average SRSi slightly increases in the fall, i.e., immediately after rainfall. In the streams, the average concentration of chlorophyll-a ranges from 9 to $33{\mu}g/l$, and is relatively high in the downstream. In contrast, in the reservoir, it is the highest in the upstream where $NH_4$ and SRP are frequently found. In particular, diatom and cryptomonad algae are bloomed in March, and blue-green algae in September; their maximum values are $108{\mu}g/l$ and $130{\mu}g/l$, respectively. Considering the concentration of N and P nutrients, pollution loads can affect the Pyeongtaek Reservoir in the downstream in this order: Ansong Stream

• Korean Journal of Ecology and Environment
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• v.50 no.4
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• pp.441-451
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• 2017

The present study was conducted from August to December 2016 in a cylindrical water tank with a diameter of 1 m, a height of 4 m and a capacity of 3,000 L. The field water and sediment from the Nakdong River were also sampled for the experimental culture (field water+sediment) and control culture (field water), respectively. In this study, we aimed to investigate phytoplankton succession pattern using the phytoplankton functional group in the enclosed culture system. A total of 50 species in 27 genera including Chlorophyceae (30 species), Bacillariophyceae (11 species), Cyanophyceae (7 species), and Cryptophyceae (2 species) were identified in the experimental and control culture systems. A total of 19 phytoplankton functional groups (PFGs) were identified, and these groups include B, C, D, F, G, H1, J, K, Lo, M, MP, N, P, S1, $T_B$, $W_0$, X1, X2 and Y. In particular, $W_0$, J and M groups exhibited the marked succession in the experimental culture system with higher biovolumes compared to those of the control culture system, which may be related to the internal cycling of nutrients by sediment in the experimental culture system. The principal component analyses demonstrated that succession patterns in PFG were associated with the main environmental factors such as nutrients(N, P), water temperature and light intensity in two culture systems. In conclusion, the present study showed the potential applicability of the functional group for understanding the adaptation strategies and ecological traits of the phytoplankton succession in the water bodies of Korea.