• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.368-370
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• 2011

Liquid manure fertilizer drived from pig slurry is a valuable source of nutrients for crop production. However, there is no study for environmental assessment regarding microbial quality to apply liquid manure fertilizer. Therefore, this study aimed at quantifying the level of environmental impact on fecal coliform (Escherichia coli or E. coli ) survival in saturated soil such as paddy field. Surface water samples were collected up to 168 and 11 hours under natural sunlight and artificial ultraviolet radiation, respectively. The inactivation rate of E. coli under natural sunlight increased gradually after 48 hours. However, the inactivation rate of E. coli under artificial ultraviolet radiation increased linearly over time. Our findings suggested that the ultraviolet radiation is the limited factor on E. coli survival in surface water of saturated soil. This result will provide useful and practical guideline to applicators of agricultural soil in deciding appropriate handling and time frames for preventing pollution of water quality for sustainable agriculture.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.517-526
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• 2011

Soil structure plays an important role in ecological system, since it controls transport and storage of air, gas, nutrients and solutions. The study of soil structure requires an understanding of the interrelations and interactions between the diverse soil components at various levels of organization. Investigations of the spatial distribution of pore/particle arrangements and the geometry of soil pore space can provide important information regarding ecological or crop system. Because of conveniences in image analyses and accuracy, these investigations have been thrived for a long time. Image analyses from soil sections through impregnated blocks of undisturbed soil (2 dimensional image analyses) or from 3 dimensional scanned soils by computer tomography allow quantitative assessment of the pore space. Image analysis techniques can be used to classify pore types and quantify pore structure without inaccurate or hard labor in laboratory. In this paper, the last 50 years of the soil image analyses have been presented and measurements on various soil scales were introduced, as well. In addition to history of image analyses, a couple of examples for soil image analyses were displayed. The discussion was made on the applications of image analyses and techniques to quantify pore/soil structure.

• Nutrition Research and Practice
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• v.13 no.1
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• pp.32-40
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• 2019

BACKGOUND/OBJECTIVES: This study investigated nutritional status of the elderly with dementia in a care facility with the aim of improving the meal quality of the facility. SUBJECTS/METHODS: Data were collected from 30 dementia patients aged more than 65 years in a long-term care facility in Hongseong. The data were obtained from questionnaires and medical records. The food intake data was obtained using food photographs and the nutrient intakes were calculated using the CAN-Pro 5.0. The data were compared with the dietary reference intakes for Koreans (KDRIs). The nutrient density, diet quality such as nutrient adequacy ratio (NAR), mean adequacy ratio (MAR), and index of nutritional quality (INQ), as well as dietary diversity score (DDS) were evaluated. The data were analyzed using SPSS statistical programs. RESULTS: The average daily energy intakes for men and women were much lower than the estimated energy requirements of the KDRIs. The average intakes of energy and most nutrients in the general diet group were significantly higher than those of the other two groups. Significant differences in diet quality and diet diversity were observed according to the meal type groups. The NARs of some minerals (calcium, iron, and zinc) and vitamins (vitamin $B_6$ and folic acid) were less than 0.5 in all study groups. The NARs of protein, iron and MAR of the general diet group were significantly higher than those of the liquid diet group. The DDS scores of meats, fruits and diary food group were very low in all meal type groups, meaning that the diet qualities of the study subjects were not appropriate in all meal type groups. CONCLUSIONS: The food intakes of the study groups showed some limitations by a direct comparison with KDRIs because of the very low physical activities of the study subjects. The diet quality and diet diversity indices suggest the need for improvements in the nutritional quality in all types of diet. Overall, new intervention strategies targeting facility residents with dementia in Korea are needed as soon as possible.

• Korean Journal of Mineralogy and Petrology
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• v.33 no.4
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• pp.377-389
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• 2020

In this study, pollution characteristics were investigated for the Andong Dam sediments in the Nakdong River. Sediment samples were collected from the middle, left, and right points of the lake up to 40km upstream of the Andong Dam at intervals of about 5km by stratification and turnover period. In the case of nutrients and total organics such as loss of ignition, total nitrogen, and phosphorus, the degree of contamination is low, but heavy metals of arsenic and cadmium is very high. The contamination level of sediments in the dam area is higher than that of the branch of river and the control group, and concentration of chromium, copper, and lead are higher in the stratification period, and that of zinc is higher in turnover period. Arsenic, cadmium, manganese, and zinc showed contamination variation between upstream and downstream but chromium, copper, mercury, iron and lead didn't show the variation.

• Research in Plant Disease
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• v.27 no.2
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• pp.49-60
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• 2021

Cashew (Anacardium occidentale L.) is an important cash crop in Tanzania as a source of income to cashew growers and provides foreign exchange for the country. Despite its significance, the crop is threatened by fast spreading disease known as cashew Fusarium wilt caused by Fusarium oxysporum. Field assessment and laboratory tests were conducted to determine incidences of the disease, severity, ecological factors that influence them and explored the pathogen host specificity in six cashew growing districts. The results revealed significant (P<0.001) variation of disease incidences and severity among the studied districts. The results further revealed that there is both positive and negative correlation between the incidence and severity of the disease versus the evaluated ecological factors. The soil pH, soil temperature, air temperature, and relative humidity depicted positive correlation of disease incidence and severity versus ecological factors at ρ=0.50 and ρ=0.60, ρ=0.20 and ρ=0.94, ρ=0.11 and ρ=0.812, ρ=0.05 and ρ=0.771 respectively while nitrogen, phosphorus, and carbon depicted negative correlations at ρ=-0.22 and ρ=-0.58, ρ=-0.15 and ρ=-0.94, ρ=-0.19 and ρ=-0.12 respectively. In terms of host range, none of the weed species was found to be a carrier of Fusarium pathogen implying that it is host specific or semi selective. The results revealed that the tested ecological parameters favor the growth and development of Fusarium pathogen. Thus, management of the disease requires nutrients replenishment and soil shading as essential components in developing appropriate strategies for the control and prevention of further spread of the disease.

• Journal of Korean Society on Water Environment
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• v.37 no.6
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• pp.520-530
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• 2021

Multivariate statistical analysis and an environmental hydrological model were applied for investigating the causes of water pollution and providing best management practices for water quality improvement in urban and agricultural watersheds. Principal component analysis (PCA) and cluster analysis (CA) for water quality time series data show that chemical oxygen demand (COD), total organic carbon (TOC), suspended solids (SS) and total phosphorus (T-P) are classified as non-point source pollutants that are highly correlated with river discharge. Total nitrogen (T-N), which has no correlation with river discharge and inverse relationship with water temperature, behaves like a point source with slow and consistent release. Biochemical oxygen demand (BOD) shows intermediate characteristics between point and non-point source pollutants. The results of the PCA and CA for the spatial water quality data indicate that the cluster 1 of the watersheds was characterized as upstream watersheds with good water quality and high proportion of forest. The cluster 3 shows however indicates the most polluted watersheds with substantial discharge of BOD and nutrients from urban sewage, agricultural and industrial activities. The cluster 2 shows intermediate characteristics between the clusters 1 and 3. The results of hydrological simulation program-Fortran (HSPF) model simulation indicated that the seasonal patterns of BOD, T-N and T-P are affected substantially by agricultural and livestock farming activities, untreated wastewater, and environmental flow. The spatial analysis on the model results indicates that the highly-populated watersheds are the prior contributors to the water quality degradation of the river.

• Journal of Nutrition and Health
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• v.55 no.6
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• pp.630-641
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• 2022

Purpose: In this study, we assessed the intake of nutrients and food groups and analyzed the nutrition quotient of obese children in South Korea. The hypothesis was that dietary quality and nutrient intake are related to the body mass index (BMI) of obese children. Methods: The participants included 48 children (20 boys and 28 girls). Based on the guidelines for the age-for-body mass index provided by the Korean National Growth Charts for children and adolescents, the participants were divided into 3 groups: overweight, BMI ≥ 85th percentile; obese, BMI ≥ 95th percentile; severely obese, BMI ≥ 99th percentile. Results: The energy distribution showed that the carbohydrate ratio was significantly higher in the overweight group (p < 0.01), whereas the fat ratio was significantly higher in the obese and severely obese groups (p < 0.05). Thus, in the overweight and obese groups, the percent body fat was negatively associated with the carbohydrate ratio (p < 0.05) but was positively associated with the fat ratio (p < 0.05). The Dietary Reference Intakes (DRI) data revealed that the intake levels of protein, vitamin B₁, vitamin B₁₂, and sodium were higher in all groups. Intakes of fiber, calcium, potassium, and magnesium were insufficient in all groups, and the DRI percent for protein was significantly higher in the obese and severely obese groups than in the overweight group. No significant differences were obtained in food group patterns or Nutrition Quotient (NQ) scores among the 3 groups. According to the evaluation results by food record and NQ, a significant difference was obtained in the dietary quality of obese children. Conclusion: We conclude that a higher intake of fat enhances weight gain. Based on the study results, we propose that the guidelines should consider the energy distribution of carbohydrate and fat intake to prevent and control obesity among Korean children.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.142-142
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• 2023

Humans inevitably and continuously produce wastewater in daily life worldwide. To decrease the degradation of river water bodies and aquatic ecosystem therein, humans have built systems at different scales to collect, drain, and treat household-produced wastewater. Particularly, municipal wastewater treatment plants (WWTPs) with centralized controls have played a key role in reducing loads of nutrients in domestic wastewater for the last few decades. Notwithstanding such contributions, impaired rivers regarding water quality and habitat integrity still exist at the whole river basin scale. It is highly attributable to the absence of dilution capacity of receiving streams and/or the accumulation of the pollutant loads along flow paths. To improve the perspective for individual WWTPs assessment, the first crucial step is to achieve systematic understanding on spatial distribution characteristics of all WWTPs together in a given river basin. By taking the initiative, our former study showed spatial hierarchical distributions of WWTPs in three large urbanized river basins in Germany. In this study, we uncover how municipal WWTPs in the contiguous United States are distributed along river networks in a give river basin. The extended spatial scope allows to deal with wide ranges in geomorphological attributes, hydro-climatic conditions, and socio-economic status. Furthermore, we identify the relation of the findings with multiple factors related to human activities, such as the spatial distribution of human settlements, the degree of economy development, and the fraction of communities served by WWTPs. Generalizable patterns found in this study are expected to contribute to establishing viable management plans for recent water-environmental challenges caused by WWTP-discharges to river water bodies.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.231-231
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• 2020

Unlike conventional treatment technologies, the performance of nature-based facilities were susceptible to seasonal changes and climatological variabilities. This study evaluated the effects of seasonal variables on the treatment performance of constructed wetlands (CWs). Two CWs treating runoff and discharge from agricultural and livestock areas were monitored to determine the efficiency of the systems in reducing particulates, organics, and nutrients in the influent. For all four seasons, the mean effluent suspended solids concentration in the agricultural CW (ACW) increased by -2% to -39%. The occurrence of algal blooms in the system during summer and fall seasons resulted to the greatest increase in the amount of suspended materials in the overlying water. unlike ACW, the livestock CW (LCW) performed efficiently throughout the year, with mean suspended solids removal amounting to 61% to 68%. Algal blooms were still present in LCW seasonally; however, the constant inflow in the system limited the proliferation of phytoplankton through continuous flushing. The total nitrogen (TN) and total phosphorus (TP) removal efficiencies in ACW were higher during the summer (21% to 25%) and fall (8% to 21%) seasons since phytoplankton utilize nitrogen and phosphorus during the early stages of phytoplankton blooms. In the case of LCW, the most efficient reduction in TN (24%) and TP (54%) concentrations were also noted in summer, which can be attributed to the favorable environmental conditions for microbial activities. The mean removal of organics in ACW was lowest during summer season (-52% to 35%), wherein the onset of algal decay triggered a relative increase in organic matter and stimulate bacterial growth. The removal of organics in LCW was highest (54 % to 55%) during the fall and winter seasons since low water temperatures may limit the persistence of various algal species. Variations in environmental conditions due to seasonal changes can greatly affect the performance of CW systems. This study effectively established the contributory factors affecting the feasibility of utilizing CW systems for treating agricultural and livestock discharges and runoff.

• Journal of the Korean Society of Food Culture
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• v.23 no.5
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• pp.655-661
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• 2008

The prevalence of atopic dermatitis (AD) in children has increased dramatically in recent years. Although AD has genetic determinants, this rapid increase is most likely due to changes in environmental influences--for example, dietary changes. The purpose of this case-control study was to assess the relationship between the risk of developing AD and dietary factors, including eating habits, food intake, and the consumption of various functional foods in children at ages of 7 or 8 years. 143 AD patients and 335 healthy children participated in this study. A mini-dietary assessment was utilized to evaluate the food intake and dietary patterns of the children, and other information, including demographic and socioeconomic characteristics, eating habits, and the frequency of functional food use was collected using a questionnaire. The results demonstrated that, among the demographic and socioeconomic factors assessed in this study, female gender, mother's employment, and the family history of AD significantly increased the risk of AD. However, no differences in dietary habits and specific food intake between AD patients and healthy controls were identified. On the other hand, the frequencies of taking multivitamin supplements, Spirulina, or gamma-linoleic acid were significantly higher in AD patients than in the controls. These data indicate that alterations in eating habits and the intake of certain foods may not be a critical cause associated with the risk of AD in school-age children, and caution should be taken in recommending food elimination diets for the purpose of preventing AD. Further studies are required in order to determine whether the intake of specific nutrients could contribute to the increase or prevention of the development of AD in school-age children.