• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.2 s.29
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• pp.111-118
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• 2007

Simple box budgets models are useful tools to understand the phenomena of natural system and to provide an insight into the complex processes including physical, chemical and biological processes occurring in natural system. Budgets of fresh water, salt and nutrients were estimated in order to clarify the characteristics of seasonal material cycle in the Masan Bay. Outflow volume of freshwater into system was approximately $307.4\times10^3\sim1,210\times10^3\;m^3/day$. Inflow masses of DIP and DIN were approximately $410.8\sim795.7\;kg/day$ and $4081.4\sim6525.3\;kg/day$, respectively. DIN is expected to accumulate in the system. The removal of nutrients from bottom sediments will contribute to the reduction of 21.0% of COD concentration in the system.

• 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.

• Journal of Nutrition and Health
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• v.41 no.4
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• pp.353-364
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• 2008

In this study elementary school children's food purchasing and consumer competency for a healthier diet were compared by their attitude toward the meal management. The subjects were 779 sixth grade elementary school children (417 boys and 362 girls) in Busan. They were classified into three groups: 'High' was composed of 226 subjects who had more than the mean +1/2 SD of attitude toward the meal management; 'Medium' was composed of 343 subjects who had the mean ${\pm}1/2$SD; and 'Low' was composed of 210 subjects who had the less than the mean -1/2 SD. The results were as follows. The high group had less pocket money than the low group, and thought that their allowances were adequate to their needs. They also had a habit of entering amounts into an account book. The children in the low group purchased mostly snacks without making or practicing a budget. The high group purchased yogurt, fruit, or bread as snacks more frequently than the low group. More children checked the nutrient facts on the package in high group than in the low group. There were no significant differences in the consumer's knowledge of a healthy diet among the groups; but there were significant differences in the consumer's skill, and the consumer's attitude toward a healthy diet among the groups. The high group had higher skills and more positive attitudes than the low group. This research suggests that education can elevate interest and can help develop more positive attitudes toward healthy diets among children. The education can help them to develop planned food purchasing habits, and improve their consumer competency for a healthy diet.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.3
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• pp.295-306
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• 2003

Recently efforts are underway to analyze the impacts of anthropogenic $CO_2$ on the global environments and the amount of oceanic uptake increase. The East Sea is now viewed as a miniature ocean because its circulation pattern is similar to the ocean conveyer belt. The biological pump of the East Sea is a vital component to understand the carbon cycle quantitatively. In this paper, the biological pump is estimated utilizing the stoichiometric ratio between carbon and phosphorus. A simple phosphate budget model is constructed based on the seawater and dissolved oxygen box model that can simulate the recent structural change in deep water circulation of the East Sea. A model run from you 1952 to 2040 shows the steadily intensifying biological pump. Currently it exports about 0.016 Pg C yr$^{-1}$ , which corresponds to 35％ of the carbon introduced into the seawater by the air-sea exchange. An increased oxygen supply to the central water mass as a result of from the transition in the ventilation system might enhance the remineralization of sinking biogenic particles. This should strengthen the upward nutrient flux into the surface layer. Consequently, the biological sequestration of anthropogenic carbon is expected to increase with time. The estimated biological uptake of the anthropogenic carbon in the East Sea since the Industrial Revolution is estimated as 0.025 Pg C.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.1
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• pp.1-10
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• 2016

In this paper, an analysis of the inflowing pollution load of the rivers in Hampyeong bay showed the average organic matter pollution loads of BOD, COD, and TOC to be 79.7 kg-BOD/day, 144.06 kg-COD/day, and 93.0 kg-TOC/day, respectively. The inflowing organic matter pollution load was the heaviest in Sonbul dike, followed by Jupo bridge and Yangman complex. With regard to season, the load characteristics were outstanding in July, the rainy period in the summer. The average inflowing pollution loads of nutrients were 20.9 kg-DIN/day, 17.1 kg-DIP/day, 148 kg-TN/day, and 37.4 kg-TP/day A comparison of the inflowing nutrients loads for each river showed the load to be the heaviest in Yangman complex, followed by Baegok bridge and Jupo bridge. In the experiment on the material budgets of Hampyeong bridge conducted using a box model, the detention time of fresh water was found to be 52.4 days, with the bay displaying the characteristics of a so dissolved inorganic nitrogen (DIN) in the nutrients material budgets, ${\Delta}DIN$ values were found to be negative, indicating the tendency of consumption and open sea leak by photosynthesis to be higher than the nitrogen that flowed in. As for dissolved inorganic phosphorus (DIP), ${\Delta}DIP$ showed positive values, indicating a tendency for accumulation as the supply through organic matter decomposition, elution load of sediments, and inflowing load of the river turned out to be higher than the consumption by phytoplankton and outflow to open sea.

• 한국해양학회지
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• v.26 no.3
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• pp.204-222
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• 1991

The annual cycles of plant major nutrients and dissolved oxygen in a nutrients-rich semi-enclosed coastal inlet, chinhae Bay, of the southern coast of the Korean Peninsula are first presented. The water column of the bay is stratified during summer (April-late September) and well0mixed during winter (October-March). During the summer stratification period, dissolved oxygen contents exceed 400uM in the surface but diminish to less than 50uM in the near bottom waters, which often results in an anoxic environment in the inner part of Chinhae Bay. After the breakdown of the stratification in October, dissolved oxygen concentration remains undersaturated until February. The evidence of allochthonous input of N-nutrients throughout the year is readily seen in the water column: however. crude budget calculations show that the nutrients are efficiently utilized within the bay ecosystem, and that export of the nutrients from the bay to the shelf must be negligible. There is no sign of the enrichment of the nutrients in the water column. The eutrophication phenomenon sensu stricto is not observed in chinhae Bay. Using the standing stock of dissolved oxygen and estimation of the oxygen fluxes across the air-sea boundary, a benthic oxygen respiration rate during winter is estimated conservatively at 21-24 mmol Cm/SUP -2/d/SUP -1/. this oxygen respiration rate accounts for about 20% of the total phytoplankton production in winter.

• Korean Journal of Environment and Ecology
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• v.15 no.3
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• pp.230-236
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• 2001

The fluxes of wet deposition(WD), throughfall(TF), stemflow(SF) and soil leachates were measured to understand base cation budgets on deciduous ecosystem impacted by acidic deposition in the north-western part of Tomakomai in Hokkaido, Japan. The flux of $H^{+}$ for wet deposition was $0.34kmo1_{c}$ $ha^{2+}$ and the flux of base cation, $K^{+}$ /, Na$^{ + }$, $Ca^{2+}$ and $Mg^{2+}$ far throughfall plus stemflow wart 1.6 kmolc $ha^{-1}$ , 3 times higher level than that for wet deposition. The flux of base cation for canopy leaching(LI) was 0.95 kmolc ha$^{-1}$ , 2.8 times higher level than $H^{+}$ sources in wet deposition. The major mechanism of $^{+}$ consumption closely related to acidic neutralizing capacity of canopy. The ionic flux for soil leachates from Boil reservoir and proton consumption in soil was dependent on soil chemical states and exchangeable Ca in soil had a major factor of H$^{+ }$ consumption. The base cation budgets on deciduous ecosystem showed positive balance fur Na, Ca and Mg, while K was the negative value.

• Journal of the Korean Society of Food Culture
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• v.22 no.2
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• pp.235-245
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• 2007

This study was undertaken to develop web-based nutrition information contents for the older adults. Twenty six domestic web-sites were analyzed and then 12 foreign web-sites and 4 education materials for the elderly of foreign university were benchmarked. Also a lot of literatures on elderly education program were reviewed. A card-sorting task was performed with 8 older adults to ascertain how the target audience organized information about nutrition. The results were as fellows. Among 26 domestic web-sites, 2 sites(7.7%) were only for the elderly. Main topics of information contents for the elderly included 'Importance of Healthy Eating', 'DRI', 'Dietary Guidelines'. Four of twelve foreign web-sites were for the elderly nutrition education. Topics of 'Dietary Guideline', 'Meal Program' were found in 4 sites and 'Importance of Healthy Eating', 'Diet & Disease', 'DRI, 'Food Guide Pyramid', 'Nutrition Fact Labels' were found in 3 sites. Education materials of foreign university dealt with basic information on 'nutrient needs changes related with aging', 'Heart & Bone Healthy Eating Plan', 'Food Guide Pyramid'. Also topics on 'Eating on a budget', 'Eating Out Guideline' were included for practical use for the elderly. Based on card-sorting process, contents framework for web-site was developed and 4 main menus for framework were respectively named as 'Nutrition', 'Meals', 'Foods'. 'Check up Nutritional Health' by panel discussion. Finally we developed nutrition information contents for 4 main menus. We focused on helping older adults recognize the importance of healthy eating and apply the nutrition information to practical use. We expect that the developed framework of contents can be a guideline for indentifying the information needs of older adults in developing effective nutrition intervention program. And we suggest that the survey for target people should be peformed for the web-site to be user-friendly designed and the developed contents be evaluated and revised in the near future.

• Journal of the Korean Geographical Society
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• v.28 no.1
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• pp.1-15
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• 1993

This research aims to investigate some respects of chemical weathering processes, espcially the amount of solute leaching, formation of clay minerals, and the chemical weathering rate of granite rocks under present climatic conditions. For this purpose, I investigated geochemical mass balance in a small catchment and the mineralogical composition of weathered bedrocks including clay mineral assemblages at four res-pective sites along one slope. The geochemical mass blance for major elements of rock forming minerals was calculated from precipitation and streamwater data which are measured every week for one year. The study area is a climatically and litholo-gically homogeneous small catchment($3.62Km^2$)in Anyang-shi, Kyounggi-do, Korea. The be-drock of this area id Anyang Granite which is composed of coarse-giained, pink-colored miner-als. Main rock forming minerals are quartz, K-Feldspar, albite, and muscovite. One of the chracteristics of this granite rock is that its amount of Ca and Mg is much lower than other granite rock. The leaching pattern in the weathering profiles is in close reltion to the geochemical mass balance. Therefore the removal or accumulation of dissolved materials shows weathering patterns of granite in the Korean peninsula. Oversupplied ions into the drainage basin were $H^+$, $K^+$, Fe, and Mn, whereas $Na^2+$, $Mg^2+$, $Ca^2+$, Si, Al and $HCO-3^{-}$ were removed from the basin by the stream. The consumption of hydrogen ion in the catchment implies the hydrolysis of minerals. The surplus of $K^+$ reflects that vegetation is in the aggravation stage, and the nutrient cycle of the forest in study area did not reach a stable state. And it can be also presumed that the accumulation of $K^+$ in the top soil is related to the surplus of $K^+$. Oversupplied Fe and Mn were presumed to accumulate in soil by forming metallic oxide and hydroxide. In the opposite, the removal of $Na^+$, Si, Al resulted from the chemical weathering of albite and biotite, and the amount of removal of $Na^+$, Si, Al reflected the weathering rate of the bedrock. But $Ca^2+$ and $Mg^2+$ in stream water were contaminated by the scattered calcareous structures over the surface. Kaolinite is a stable clay mineral under the present environment by the thermodynamical analysis of the hydrogeochemical data and Tardy's Re value. But this result was quite different from the real assemblage of clay miner-als in soil and weathered bedrock. This differ-ence can be explained by the microenvironment in the weathering profile and the seasonal variation of climatic factors. There are different clay forming environments in the stydy area and these differences originate from the seasonal variation of climate, especially the flushing rate in the weathering profile. As it can be known from the results of the analysis of thermodynamic stability and characteristics of geochemical mas balance, the climate during winter and fall, when it is characterized by the low flushing rate and high solute influx, shows the environmental characteristics to from 2:1 clay minerals, such as illite, smectite, vermiculite and mixed layer clay minerals which are formed by neoformation or transformation from the primary or secondary minerals. During the summer and spring periods, kaoli-nite is a stable forming mineral. However it should consider that the other clay minerals can transformed into kaolinite or other clay minerals, because these periods have a high flushing rte and temperature. Materials which are directly regulated by chemical weathering in the weathered bedrock are $Na^+$, Si, and Al. The leaching of Al is, however, highly restricted and used to form a clay mineral, and that of Si falls under the same category. $Na^+$ is not taked up by growing veget ation, and fixed in the weathering profile by forming secondary minerals. Therefore the budget of $Na^+$ is a good indicator for the chemical weathering rate in the study area. The amount of chemical weathering of granite rocks was about 31.31g/$m^2+$/year based on $Na^+$ estimation.