• Journal of Wetlands Research
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• v.22 no.1
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• pp.49-58
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• 2020

The excessive use of fertilizer and compost in agricultural land increases the accumulation of nutrients in soil. The surplus nutrients in soil transported through surface and sub-surface flow can lead to water pollution problems and algal bloom. Moreover, nutrient accumulation and continuous crop cultivation changes the physical structure of the soil, which increases the potential of nutrient. The cultivation in the Daecheong Lake reservoir area may have a direct effect on the lake's water quality due to leaching and releasing of nutrients when water level rises. This research was carried out to analyze the physical and chemical properties of soil in the agricultural areas surrounding Daecheong Dam reservoir to provide basic data available for the establishment of Daecheong Lake water quality management measures. The soil of the Daecheong Lake reservoir was classified as sandy Loam, where surplus nutrients can be transported. Chemical compositions in the soil were found to be significantly affected by use of different fertilizer amounts. Nutrient outflow occurred during spring rainfall events from the rice paddy fields, whereas excess nutrients from summer to fall seasons originated from dry paddy fields. Nutrient outflow from dry paddy fields is mainly from sub-surface flow. Organic agricultural wastes from agricultural land and excessive vegetation inside the river was also evaluated to contribute to the increase in organic matter and nutrients of the river. The results can be used to select the priority management area designation and management techniques in the Daecheong Lake for water quality improvement.

• Journal of Nutrition and Health
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• v.28 no.7
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• pp.653-674
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• 1995

This study was aimed at comparing the dietary patterns of university female students according to their residence type. As for subjects, one hundred and twenty students of Kongju national university were chosen as a total. They were devided into three groups ; those who live in family home, or university dormitory, or self-boarding house. In this study, intakes of food and nutrient and dietary behaviors of each group were investigated through two-day food records and questionnaire. The result was that mean daily intakes of calcium and iron were lower than RDAs in all groups. According to residence type, subjects of family home and self-boarding seemed to have more serious problem in the nutrients mentioned above considering the proportions of less than 2/3 of RDAs. Especially, iron status was poorer than any other nutrients in the aspects of this proportion and food source. Iron was taken largely from vegetable foods which were recognized as a source of low bioavailability of iron. The average distribution ratios of breakfast, lunch, dinner and snack to total calorie intake was 22, 29, 30 and 19. Thus, it proved that breakfast tended to be more negligent than any other meals, and that snack was an important means to give nutrients for subjects. This meal pattern might be one of the factor for the decrease of the dietary quality. Processed foods were founded to be an important source for providing nutrients. Percentages of calorie, carbohydrate and fat consumed by processed foods to total nutrients. Percentages of calorie, carbohydrate and fat consumed by processed foods to total nutrients intake were 30.6, 29.5 and 46.2. However, other nutrient intakes from processed foods such as vitamin and mineral were small. And processed foods which give nutrients were mainly cereal products like ra myon, bread, and milk and milk products. Consequently, processed foods seemed to be selected as a combinient substitute food which supply calorie to fill their hunger. According to the living type, dormitory students had them more frequently than any other groups. Food habit score was within the category of poor or fair. Particularly, the score of self-boarding students was the lowest of groups(p<0.05). The major dietary problems were small or overating, missing meal and irregular eating. The degree of these problems was a little different among groups(P<0.01). Nineteen kinds of food were consumed per day, and family home and self-boarding students had foods less variously than dormitory students(P<0.05). Proportions of skipping breakfast, lunch and dinner were 20.8, 12.5 and 8.3%. Accordingly, breakfast was missed more often than any other meals. And self-boarding students missed breakfast more often than any other groups. As a conclusion, subjects should take more calcium and iron, and eat diverse foods to improve their nutritional status. And it is also necessary that breakfast should be regarded more importantly, and that processed foods should be taken considering nutritional balance. In view of residence type, subjects of family home or self-boarding had more dietary problems than dormitory subjects. Thus, these results suggest that university female students might have low ability of meal management, and dietary patterns were different by their residence type. Therefore, nutrition education for them should be carried out with respect to dewelling environment.

• Ocean and Polar Research
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• v.27 no.3
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• pp.251-263
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• 2005

In order to study changes in the marine ecosystem of the East China Sea derived by the global warming and construction of the Three Gorges Dam in the middle of the Changjiang, temperature, salinity, nutrients, and chlorophyll-a were studied intensively in the northern part of the East China Sea during the summer of 2003 and spring of 2004. According to the previous studies, the upwelling of the Kuroshio Current and the Changjiang resulted in a major inputs of nutrients in the East China Sea, but these two inputs may not contribute gently to a build up of nutrients in the northern East China Sea. In spring, relatively high concentrations of nitrates and phosphates were observed in the western part of the study area, which resulted from the supply of high concentrations of nutrients showing up in the surface waters as a result of vertical mixing from the ocean bottom. The concentrations of nitrates and phosphates observed in summer were lower than those in spring, since the surface waters were well stratified by the larger discharge of fresh water from the Changjiang in summer. The surface nitrate/phosphate ratios ranged from 1.3 to 16 in spring and from 1.1 to 15 in summer and were lower than the Redfield ratio of 16, indicating that the growth of phytoplankton is limited by nitrogen. This results are contrary to the previous results, in which the growth of phytoplankton was limited by phosphate in the East China Sea. The reason for this contrary result is that most nutrients in the surface waters are supplied by vertical mixing from the bottom waters with low nitrate/phosphate ratios, not directly influenced by the Changjiang with high nitrate/phosphate ratios. The depth-integrated chlorophyll observed in summer was similar to the previous results, but those measured in spring were almost twice as high as those found in previous results. The depth-integrated chlorophyll in spring was higher than that of summer, which results from high concentrations of nitrates and phosphates in the surface waters in spring due to active vertical mixing.

• Journal of Nutrition and Health
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• v.23 no.5
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• pp.309-316
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• 1990

The relationship between diet diversity and nutrient intake was studied. Diet diversity, caloric intake and dietary nutrient density values were examined as contributors to the level of selected nutrients with the use of data obtained from 14-day dietary records of 60 college women. The subjects were grouped into quartiles on the basis of level of intake of each of the specific nutrients. The indexes of diet diversity were the number of different food items and Shannon & Weaver's diversity index. Differences in diet diversity were found among nutrients and indexes. In general, calorie and protein intake were more diverse, on the other hand, intake of vitamins A and C were less diverse. With the exception of calcium, iron, vitamin $B_1$, niacin and vitamin C, the number of food items increased at each quartile of intake of specific nutrients. It was concluded that for some nutrients(as with fat), the number of food items consumed may be useful in estimating nutrient intakes. For other nutrients(as with calcium), utilization of nutrient-specific diversity indexes is necessary. Increased nutrient intake was accompanied by increased caloric intake(except vitamins A and C) and dietary nutrient density for all nutrients.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.701-711
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• 2000

To provide the baseline information for establishing community based nutritional service system in the context of health promotion, we conducted nutrition survey for 196 adults (male ; 99, female ; 97) in Kyungpook area. Individual food intake was measured by 24-hour recall method, and then diet quality was evaluated by Index of Nutritional Quality (INQ) and Mean Adequacy Ratio (MAR). Average dietary intake of Ca and Vit A of total subjects were lower than Korean Recommended Dietary Allowances (Ca; 83% of RDA, Vit A; 77% of RDA). On the whole, mean nutrients intake of male subjects were higher than that of female subjects. It also appeared that overall nutrients intake of younger women (20~29 yr) were lower than that of other age group. When we evaluated the nutrients intake of the subjects by INQ, Vit C (=2.39) showed the highest score. Ca (=0.89) and Vit A (=0.84) were revealed to be concerned nutrients in both quantity and quality. There was almost no difference in MAR between men and women (Men ; 0.88, Women ; 0.86). MAR showed significantrly positive correlation with age (p<0.05), meal frequency (p<0.001) and negative correlation with education level (p<0.01) in women, whereas no statistically significant relationship among these variables was observed in men. Age and meal frequency showed significantly positive correlation with most nutrients intakes among women. In conclusion, nutrition education strategies for sound food choice and regular meals need to be developed to improve the nutritional adequacy of female adults in the 20's.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.6
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• pp.679-686
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• 2010

To investigate the contribution of macroalgae to biogeochemical nutrients and carbon cycles, we measured the uptake rates of nutrients and $CO_2$ by Undaria pinnatifida using an incubation method in an acrylic chamber. From January to March 2010, U. pinnatifida was sampled at Ilkwang, a well-known area of macroalgae culture in Korea. The initial and final concentrations of nutrients, dissolved oxygen, total alkalinity, and pH of the chamber water were measured, and production/uptake rates were calculated using concentration changes, chamber volume, and incubation time. The production rate of dissolved oxygen by U. pinnatifida (n = 32) was about $5.4{\pm}4.0\;{\mu}mol\;g_{fw}^{-1\;}h^{-1}$. The uptake rate of total dissolved inorganic carbon (TDIC), calculated by total alkalinity and pH, was $7.9{\pm}6.5\;{\mu}mol\;g_{fw}^{-1}\;h^{-1}$. Nutrients uptake averaged $141.7{\pm}119.2$ nmol N $g_{fw}^{-1}\;h^{-1}$ and $15.0{\pm}9.1$ nmol P $g_{fw}^{-1}\;h^{-1}$. A positive linear correlation ($r^2$ = 9.6) existed between the production rate of dissolved oxygen and the uptake rate of total dissolved inorganic carbon, suggesting that these two factors serve as good indicators of U. pinnatifida photosynthesis. The relationships between fresh weight and uptake rates of nutrients and $CO_2$ suggested that younger specimens (<~50 g fresh weight) are much more efficient at nutrients and $CO_2$ uptake than are specimens >50 g. The amount of carbon uptake by the total biomass of U. pinnatifida in Korea during the year of 2008 was about 0.001-0.002% of global ocean carbon uptake. Thus, more research should be focused on macroalgae-based biogeochemical cycles to evaluate the roles and contributions of macroalgae to the global carbon cycle.

• Journal of the Korean Dietetic Association
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• v.9 no.4
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• pp.307-315
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• 2003

This study was to investigate the relation of nutrients intake, health status, and bone mineral density in middle-aged women. Daily nutrients intake were analyzed by convenient method. The BMD of subjects were measured by Dual Energy X-ray Absorptiometry(DEXA). BMD was measured at the spine(vertebrae L2-L4) and femur(neck, Ward's triangle and trochanter). The nutrients intake of subjects were higher than recommended dietary allowances(RDA) except for calorie, iron, calcium, vitamin B1. Nutrients intake of vitamin A(p<0.05), iron(p<0.01), vitamin $B_2$(p<0.05), niacin(p<0.05), and vitamin C(p<0.05) between $\leq$49 yr group and $\geq$50 yr group. Mean daily intake of calcium was much less than the Korean RDA, 78.5% in $\leq$49 yr group and 77.3% in $\geq$50 yr group. 35.8% of the subjects under 50 years of age($\leq$49 yr group) and 77.4% of the subjects from 50 years up($\geq$50 yr group) were classified as osteopenia or osteoporosis. BMD of L2-L4 were positively correlated with height(p<0.05), weight(p<0.05) and BMI(p<0.05). BMD of femoral neck was positively correlated with BMI(p<0.05), BMD of Ward's triangle was positively correlated with weight(p<0.001). But BMD of L2-L4 and femoral neck were negatively correlated with age(p<0.05), menarche(p<0.05). BMD of Ward's triangle was negatively correlated with age(p<0.001). The BMD of L2-L4 were positively correlated with animal protein(p<0.05), calcium(p<0.05) and iron(p<0.05). The BMD of femoral neck was positively correlated with animal protein(p<0.05). The BMD of Ward's triangle was positively correlated with animal protein(p<0.001) and iron(p<0.001). The above results suggest that it should be difficult to prevent middle-aged women's bone destruction through nutrients intake. Further investigation is necessary to prove the mutual relations between BMD, exercise, and calcium intake. Therefore, middle-aged women will need proper exercise as well as Ca supplementation in order to prevent osteoporosis with aging.

• 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.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.6
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• pp.627-639
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• 2014

In respect of the nutrients cycling in coastal environment, regeneration in bottom layer is one of major source of nutrients. We analyzed the bottom water quality at the 14 stations during 9 years from 2004 to 2012 to investigate the characteristics of nutrients at bottom layer in Jinhae Bay. Concentrations of DIN, DIP and DSi showed the large seasonal variation and were higher in summer. Especially, average concentrations of these nutrients were two times higher in hypoxic season than in normoxic season. In summer, high concentrations of DIN, DIP and DSi caused by regeneration were common feature, but spatial distribution of DSi differ from that of DIN and DIP. DIN and DIP were higher in Masan Bay, while DSi was higher in Masan Bay as well as in center of Jinhae Bay. In comparison with DIN and DIP, DSi was significantly affected by nutrients regeneration at bottom layer in whole season. According to time series analysis, DIN concentration was decreased from approximately $14{\mu}M$ to $6{\mu}M$. This result induce that Si:N ratio at bottom layer in Jinhae Bay changed from approximately 1 to 3.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.3
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• pp.423-431
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• 2001

Animals are one of the important memberships of the food chain. The low-efficiency rule of nutrient transfer from one member to the next in the food chain determines the low efficiency of animal agriculture for human food. On the average, about 20% feed proteins and 15% feed energy can be converted into edible nutrients for humans. The rest proportion of feed nutrients is exposed to the environment. Environmental pollution, therefore, is inevitable as animal agriculture grows intensively and extensively. The over-loading of the environment by nutrients such as nitrogen, phosphorus from animal manure results in soil and water spoilage. The emission of gases like $CH_2$, $CO_2$, $SO_2$, NO, $NO_2$ by animals are one of the contributors for the acidification of the environment and global warming. The inefficient utilization of natural resources and the probable unsafety of animal products to human health are also a critical environmental issue. Improving the conversion efficiency of nutrients in the food chain is the fundamental strategy for solving environmental issues. Specifically in animal agriculture, the strategy includes the improvements of animal genotypes, nutritional and feeding management, animal health, housing systems and waste disposal programs. Animal nutrition science plays a unique and irreplaceable role in the control of nutrient input and output in either products or wastes. Several nutritional methods are proved to be effective in alleviating environmental pollution. A lot of nutritional issues, however, remain to be further researched for the science of animal nutrition to be a strong helper for sustainability of animal agriculture.