• Korean Journal of Ecology and Environment
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• v.39 no.1 s.115
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• pp.73-84
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• 2006

The objective of this study was to analyze long-term temporal trends of water chemistry and spatial heterogeneity for 10 sampling sites of the Yeongsan River watershed using water quality dataset during 1995 to 2004 (obtained from the Ministry of Environment, Korea). The water quality, based on multi-parameters of biological oxygen demand (BOD), chemical oxygen demand (COD), conductivity, dissolved oxygen (Do), total phosphorus (TP), total nitrogen (TN) and total suspended solids (TSS), largely varied depending on the sampling sites, seasons and years. Largest seasonal variabilities in most parameters occurred during the two months of July to August and these were closely associated with large spate of summmer monsoon rain. Conductivity, used as a key indicator for a ionic dilution during rainy season, and nutrients of TN and TP had an inverse function of precipitation (absolute r values> 0.32, P< 0.01, n= 119), whereas BOD and COD had no significant relations(P> 0.05, n= 119) with rainfall. Minimum values in conductivity, TN, and TP were observed during the summer monsoon, indicating an ionic and nutrient dilution of river water by the rainwater. In contrast, major inputs of total suspended solids (TSS) occurred during the period of summer monsoon. BOD values varied with seasons and the values was closely associated (r=0.592: P< 0.01) with COD, while variations of TN were had high correlations (r=0.529 : P< 0.01) with TP. Seasonal fluctuations of DO showed that maximum values were in the cold winter season and minimum values were in the summer seasons, indicating an inverse relation with water temperature. The spatial trend analyses of TP, TN, BOD, COD and TSS, except for conductivity, showed that the values were greater in the mid-river reach than in the headwater and down-river reaches. Conductivity was greater in the down-river sites than any other sites. Overall data of BOD, COD, and nutrients (TN, TP) showed that water quality was worst in the Site 4, compared to those of others sites. This was due to continuous effluents from the wastewater treatment plants within the urban area of Gwangju city. Based on the overall dataset, efficient water quality management is required in the urban area for better water quality.

• Horticultural Science & Technology
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• v.32 no.2
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• pp.157-164
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• 2014

Objective of this research was to develop root media containing expanded rice hull (ERH) and carbonized rice hull (CRH). To achieve this, the physico chemical properties of two materials were analysed and blended with peatmoss (PM) or coir dust (CD) with various ratio. Based on the physical properties of the blended materials, 4 root media were selected for future experiment. After the analysis of pH and EC of the selected root media, the kinds and amount of pre-planting nutrient charge fertilizers (PNCF) incorporated into each root medium were varied, and then, final chemical properties of the root media were analysed. The total porosity (TP), container capacity (CC), and air-filled porosity (AFP) were 81.3%. 39.9%, and 41.4% in ERH and 77.6%, 64.1%, and 13.5% in CRH, respectively. The percentage of easily available water (EAW, from CC to 4.90 kPa tension) and buffering water (BW, 4.91-9.81 kPa tension) were 11.37% and 5.27%, in ERH and 17.26% and 14.28% in CRH, respectively. The pH of ERH was 7.1, but it was extremely high in CRH such as 11.2. The EC and CEC were $1.31dS{\cdot}m^{-1}$ and $12.1meq{\cdot}100g^{-1}$ in ERH and $6.53dS{\cdot}m^{-1}$ and CEC 7.79 $meq{\cdot}100g^{-1}$ in CRH, respectively. The ranges of TP, CC and AFP in 4 selected media (PM + ERH, 6:4, v/v; CD + ERH, 8:2; PM + CRH, 7:3; CD+CRH 6:4) were 89.2-90.3%, 67.3-81.8%, and 8.3-21.9%, respectively. The pHs and ECs in root media containing peatmoss such as PM + ERH (6:4) and PM + CRH (7:3) were 4.0-4.3 and $0.33-0.365dS{\cdot}m^{-1}$, whereas those of CD + CRH were 7.4-7.9 and $1.282dS{\cdot}m^{-1}$. The pHs and ECs, however, analysed before and after the incorporation of PNCF in each root medium were not significant different. This result indicated that the incorporated fertilizers in PNCF to adjust medium pH did not dissolve enough to influence medium pH, but it is very normal in root media containing dolomitic lime and sulfur powder in adjusting pH. The Information obtained in this study may facilitate an effective formulation of root media containing rice hulls.

• Journal of Nutrition and Health
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• v.53 no.4
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• pp.416-430
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• 2020

Purpose: This study was conducted to assess the effects of a personalized nutritional intervention program on food security and health and nutritional status of elderly people in the city of Seoul. Methods: A total of 372 elderly adults aged 65 years or above who resided in Seoul were enrolled in this study. Personalized supplementary food supply and nutritional education based on chronic disease status, disability and cooking ability were implemented for 4 months. To evaluate the effectiveness of the program, nutrient intake, food security status, anemia status, chronic disease management, and frailty status, and prevalence of malnutrition (Mini Nutritional Assessment) were examined. Results: After the program, all subjects displayed significantly increased nutrient intake. Before the intervention, all subjects were in a state of food insecurity; however, after the intervention, 37.1% of the subjects were food secure. Moreover, the rates of being at risk of malnutrition and malnutrition in subjects were decreased and instead rate of those who improved to normal increased to 29.8% from 0% of normal rate before the prevention. The rate of subjects without anemia increased from 18.7% to 28.5% after the intervention. In addition, the rate of subjects with intensive or periodic management of chronic diseases decreased, while those with occasional management of chronic diseases increased from 0% to 4.6%. Furthermore, the rates of being at risk of frailty and frailty were decreased and the normal rate increased from 0% to 9.7% instead. Age group-based analysis showed that elderly people over 80 years showed less improvement in the management of the chronic disease status and the frailty status. Conclusion: Personalized supplementary food supplies and nutritional education improved not only the nutritional status but also disease status in vulnerable older adults, and the effects were more significant in adults aged less than 80 years.

• Korean journal of applied entomology
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• v.57 no.2
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• pp.97-104
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• 2018

The larva of the white-spotted flower chafer, Protaetia brevitarsis seulensis (Coleoptera: Cetoniidae), is known to have important medicinal properties, such as anti-cancer activity. However, the consumer market for the larvae is depressed because of its high production cost which needs to be reduced. This study was carried out to evaluate two spent mushroom substrates as food source for chafer larvae to improve the productivity and reduce production cost. The larvae were fed with spent substrates of king oyster mushroom (Pleurotus eryngii) (P-SMS) and shiitake mushroom (Lentinula edodes) (L-SMS), with a control of fermented oak sawdust. Effects of the diets on the development of P. brevitarsis seulensis and contents of minor nutrient components in the larvae produced were examined. In the P-SMS diet, the larval rearing period was shorter at 16.2 days, while the rate of larval weight gain and the cocoon weight were higher at 156.3% and 4.1 g, respectively, than that in the L-SMS diet. The pupation rate was 100% and the adult emergence was higher at 93.3% in the P-SMS diet than in the L-SMS diet with no difference to the control diet. In the P-SMS diet, the total nitrogen content during rearing was higher at 10.28% and the minor nutrient component, particularly Fe (145.8 mg/kg), was higher than that in other diets. The oviposition preference of adults showed no significant difference among the diets. Economic analysis showed that P-SMS costs approximately 667,960 Won less per 100 kg of larvae produced, compared to that of the control diet.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.1
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• pp.175-182
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• 2001

The main focus of this study was set to help college students in Kangwon province to improve and correct dietary habits and to maintain healthy life. The nutritional status and food preference of college students were examined from May to July, 1999. The collection of the research data has been made on the basis of questionnaries for 184 college students residing in Kangwon province. Statistical analysis of the data was performed using SAS package program for descriptive frequency and statistical significance. The meal skipping ratio of the subjects were 2% and for the reasons of meal skipping 45% responded "lack of time". As for main dishes, cooked rice turned out to be the most preferred by the subjects and the second and third favored by female students were bread and noodle respectively. Most preferred side-dishes were meat soup, kimchi, laver Kui,squid Bockeum, fried squid, beef Chon, squid Chorim, soy Namul, Dubuk Changachi and squid Muchim. Less preferred side-dishes include radish soup, white kimchi, mugwort fry, liver Bockeum, liver sheon and egg plant Kui. No one-plate food was disliked by the subjects. Male liked Manndukuk and female liked cuttle fish rice. The intakes of nutrient except for energy, iron and calcium for female students were the same or above the Recommended Dietary Allowances (RDA) for Koreans.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.251-256
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• 2010

Objective of this research was to investigate the influence of $NH_4^+$ and $NO_3^-$ ratios in liquid feeding on the growth of snapdragon 'Potomac Red' and changes in medium chemical properties. The seeds were sown into 200 plug trays and fertigated once a week with nutrient solution containing various ratios of $NH_4^+$ and $NO_3^-$ such as 0 : 100, 27 : 73, 50 : 50, 73 : 27, and 100 : 0. The total N concentrations were adjusted to 50, 100 and $150\;mg{\cdot}L^{-1}$ in plug stages of 2, 3, and 4, respectively. Determination of seedling growth and analysis of plant tissue and root medum were conducted at 56 days after sowing. The treatment of 27 : 73 ($NH_4^+:NO_3^-$) had the greatest plant height, fresh weight, and dry weight. The N and P contents in 27 : 73 ($NH_4^+:NO_3^-$) treatment based on the above ground plant tissues were 2.39 and 0.39%, respectively, which were the greatest among treatments. The elevation of $NH_4^+$ ratio in fertigation solution decreased tissue Ca and Mg contents, but that did not influence tissue K content. The variations in $NH_4^+:NO_3^-$ ratios impacted the soil solution pH and the difference among treatments had been severe since three weeks after sowing. Elevation of $NH_4^+$ ratios in fertigation solution increased electrical conductivity and concentrations of K, Ca, and Mg in soil solution of root medum. The $NH_4^+$ and $NO_3^-$ concentrations in the soil solution were high in weeks 2, 3, and 4, then decreased gradually as the biomass of seedlings increased. Medium P concentration decreased gradually as seedlings grew, but statistical differences were not observed among treatments.

• Korean Journal of Environmental Agriculture
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• v.29 no.3
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• pp.227-231
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• 2010

Slurry composting biofiltration(SCB) is considered as a treatment to produce a better fertilizer resource than raw pig slurry as it reduces odor and improves nutrients imbalance. For the agricultural use of SCB slurry as a nutrient source with minimum environmental impact, it is important to investigate the effect of different rate of SCB slurry application on nutrient (particularly for nitrogen) uptake and growth of crops. This study was conducted to investigate the influence of fertigation using pig slurry(PS) on growth and yield of red pepper and to evaluate the appropriate PS concentration in fertigation for soils with different nitrate concentration. To evaluate the effects of fertigation applied PS as a substitute of chemical fertilizer(CF), a single application of three different concentrations of PS: $N_{0.5}$ (43 mg/L), $N_{1.0}$ (86 mg/L) and $N_{1.5}$ (131 mg/L) were compared with CF $N_{1.0}$ (89 mg/L) as a control nitrogen fertilizer. Statistical analysis showed that the growths of red pepper were not affected by treatments. In addition, the yields were no significant difference among treatments, though the highest yield was obtained in PS $N_{1.0}$ by 20,580 kg/ha. In soil chemical properties, nitrate nitrogen on soil of between PS N1.0 and CF $N_{1.0}$ treatment showed similar patterns although they were higher than the preplant nitrogen content. Also, there was no significant difference in yield of red pepper between PS and CF treatment applied as fertigation on soils where nitrate nitrogen contents of each soil contains 10, 100 and 200 mg/kg respectively. Consequently, the application of PS, such as SCB, as a substitute of CF is available for growth and yield of red pepper, there could be accordingly estimated the optimal fertigation concentration of PS for red pepper cultivation.

• Korean Journal of Environmental Biology
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• v.31 no.1
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• pp.19-36
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• 2013

Physiochemical characters of sea waters during summer flood- and winter dry-seasons and their spatial variations were investigated along the coastal area off the eastern South Sea, Korea. Using the hierarchical clustering method, in this study, we present comprehensive analyses of coastal waters masses and their seasonal variations. The results revealed that the coastal water of the study area was classified into six water masses (A to F). During summer season, the surface water was mainly occupied by the coastal pseudo-estuarine water (water mass B) with low salinity and high nutrients and the river-dominated coastal water (water mass C) with low nutrients, respectively. The bottom water was dominated by cold water (water mass D) with very low temperature, high salinity and high nutrients, compared to masses of surface water. Notably, the water mass B, with high concentrations of nutrients (silicate and nitrogen) and low salinity, which is strongly controlled by the water quality of river freshwater, seems to play an important role in controlling the water quality and further regulating physical processes on ecosystem in the eastern coastal area of South Sea. The water mass D (bottom cold water) coupled with a strong thermocline, which exists in near-bottom layer along the western margin of Korea Strait, has a low temperature, pH and DO, but abundant nutrients. This water mass disappears in winter owing to strong vertical mixing, and subsequently may act as a pool for nutrients during winter dry-season. On the other hand, vertically well-mixed water column during the winter season was typically occupied by the Tsushima (water mass E) and the coastal water (water mass F) with a development of coastal front formed in a transition zone between them. These winter water masses were characterized by low nutrient concentration and balance in N/P ratio, compared with summer season with high nutrient concentrations and strong N-limitation. Accordingly, the analysis of water masses will help one to better chemical and biological processes in coastal area. In most of the study area, characteristically, the growth of phytoplankton community is limited by nitrogen, which is clearly different with coastal environment of West Sea of Korea, with a relative lack of phosphorus. It showed the western and the southern coasts in Korea are substantially different from each other in environmental and ecological characteristics.

• Journal of Nutrition and Health
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• v.35 no.4
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• pp.480-488
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• 2002

This study was performed to document the association between obesity, a major risk factor for chronic diseases, and dietary pattern in Korean elderly. The subjects were 595 men and women aged 60-89 years. The subjects were classified into 4 groups based on BMI: under weight, BMI < 18.5, normal weight, 18.5 $\leq$ BMI 22.9; overweight, 23.0 BMI 24.9; and obese BMI $\geq$ 25.0. Dietary intakes by 24-hr recall, blood pressure, anthropometric parameters and health eating index (HEI) were measured. Underweight group was excluded for data analysis doe to small number of subjects, and age-adjusted measurements were compared among normal, overweight and obese groups. The mean anthropometric values for males and females were 23.7 and 24.8 kg/$m^2$ for BMI, 0.90 and 0.86 for WHR and 140.7 and 138.8 mmHg for SBP, respectively. The mean intakes of energy, Ca, vitamin A, vitamin B$_2$, and vitamin E did not meet Korean RDA for elderly. Intakes of fat and cholesterol were low: the percent energy from fat for male and female subjects were 19.1% and 18.1% and mean cholesterol intakes were 208 mg and 152 mg, respectively. Judging by HEI score, dietary quality was better in females than in male subjects. The mean BMI of normal, over and obese groups were 21.4, 23.9, 26.7 kg/$m^2$ in male subjects and 21.6, 23.9, 27.1 kg/$m^2$ in female subjects. WHR, SBP and TSF were increased with increasing BMI No association was found between BMI and nutrient intakes and/or food consumption pattern. However, a tendency was shown that the overweight group reported higher intakes in most nutrients compared to normal and obese groups. This study implies that with increasing BMI, anthropometric risk factors, such as WHR, TSF, and blood pressure were Increased, however, no significant differences were found in nutrient intakes and food patterns. Energy and fat intakes do not seem to be a cause for obesity in Korean elderly.

• Journal of Nutrition and Health
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• v.35 no.4
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• pp.473-479
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• 2002

This study investigated associations between calcium intake, exercise behaviors, lumbar bona mineral density (BMD), and bone mineral content (BMC) among 79 premenopausal women (mean age = 41yr). The BMD and BMC of the lumbar spine (L$_2$-L$_4$) were measured by dual energy x-ray absorptiometry. Nutrient intake was estimated by the convenient method and a quantitative food frequency questionnaire was designed for this study that included the most commonly consumed floods sources of Ca. Participants were asked to identify all activities of exercise they had participated in including estimation of number of years of participation, number of weeks per year, number of times per week, and the number of hours per session. Participants were then categorized into the exercise group or nonexercise group (control). To meet the criteria for inclusion in the exercise group, the subjects participated more than 3 sessions per week and more than 30 minutes per session and the length of the exercise participation was at least more then 6 months. The participants were also grouped by calcium intake. The total calcium intake of all participants was estimated by dietary calcium intake and then the subjects were divided into quartiles to assess the lumbar BMD and BMC of the upper 25% (average calcium intake = 910 mg) and the lower 25% (average calcium intake = 414 mg). Results indicated that there were no significant differences in energy and calcium intake, and that there were no significant differences in lumbar BMD and BMC between participants in exercise group and the nonexercising control group. However, the exercise group had significantly lower ALP concentration than the nonexercise group. The upper 25% calcium intake group had significantly greater lumbar bone mineral density and bone mineral content than the lower 25% calcium intake group. Also the upper 25% calcium intake group had significantly lower ALP concentration than the lower 25% calcium intake group. Correlation analysis revealed that the spinal BMB was positively associated with body weight, while calcium intake was negatively associated with ALP concentration in nonexercising women. However, neither body weight nor dietary calcium intake were associated with both spinal BMD or ALP concentration in exercising women. These results suggest that calcium intake positively influence bone mineral density and bone mineral content in nonexercisulg premenopausal women. Exercise group did not affected by body weight and dietary calcium, but decreased ALP concentration than nonexercising group. Both exercise and calcium intake positively influence bone mineral density and bone mineral content in premenopausal women.