The effects of different environmental factors on biochemical composition of particulate organic matters in Gwangyang Bay, South Korea

Abstract. Biochemical composition of particulate organic matter (POM) through phytoplankton photosynthesis is important to determine food quality for planktonic consumers as well as physiological conditions of phytoplankton. Major environmental factors controlling for the biochemical composition were seasonally investigated in Gwangyang Bay which has only natural conditions (e.g., no artificial dams) in South Korea. Water samples for the biochemical compositions were obtained from three different light depths (100 %, 30 %, and 1 %) mainly at 3 sites in Gwangyang bay from April 2012 to April 2013. Different biochemical classes (carbohydrates [CHO], proteins [PRT], and lipids [LIP]) were extracted and then the concentrations were determined by the optical density measured with a spectrophotometer. The highest and lowest of PRT compositions among the three biochemical classes were in April 2012 (58.0 %) and August 2012 (21.2 %), whereas the highest and lowest LIP compositions were in August 2012 (49.0 %) and April 2012 (24.8 %), respectively. CHO composition was recorded high in January 2013 and maintained above 25 % during the study period. The calorific contents of food material (FM) ranged from 1.0 Kcal m−3 to 6.1 Kcal m−3 (annual mean ± S.D. = 2.8 Kcal m−3 ± 1.1 Kcal m−3). Based on Pearson's correlation coefficient analysis, a major governing factor for biochemical composition of POM was dissolved inorganic nitrogen loading from river-input in Gwangyang bay. In conclusion, relatively larger amount of FM and higher calorific contents of POM found in this study compared to other regions reflected good nutritive conditions for sustaining productive shellfish and fish populations in Gwangyang bay. Continuous observations are needed for monitoring marine ecosystem response to potential environmental perturbations in Gwangyang bay.

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The effects of different environmental factors on the biochemical composition of particulate organic matter in Gwangyang Bay, South Korea

Biogeosciences ◽

10.5194/bg-14-1903-2017 ◽

2017 ◽

Vol 14 (7) ◽

pp. 1903-1917 ◽

Cited By ~ 12

Author(s):

Jang Han Lee ◽

Dabin Lee ◽

Jae Joong Kang ◽

Hui Tae Joo ◽

Jae Hyung Lee ◽

...

Keyword(s):

Organic Matter ◽

Environmental Factors ◽

South Korea ◽

Particulate Organic Matter ◽

Biochemical Composition ◽

Inorganic Nitrogen ◽

Marine Ecosystem ◽

Nitrogen Loading ◽

Food Material ◽

Gwangyang Bay

Abstract. The biochemical composition of particulate organic matter (POM) produced through phytoplankton photosynthesis is important in determining food quality for planktonic consumers as well as the physiological conditions of phytoplankton. Major environmental factors controlling the biochemical composition were seasonally investigated in Gwangyang Bay, South Korea, which has only natural conditions (e.g., no artificial dams). Water samples for the biochemical compositions were obtained from three different light depths (100, 30, and 1 %) mainly at three sites in Gwangyang Bay from April 2012 to April 2013. Different biochemical classes (carbohydrates, CHO; proteins, PRT; and lipids, LIP) were extracted, and then the concentrations were determined by the optical density measured with a spectrophotometer. The highest and lowest PRT compositions among the three biochemical classes were found in April 2012 (58.0 %) and August 2012 (21.2 %), whereas the highest and lowest LIP compositions were found in August 2012 (49.0 %) and April 2012 (24.8 %), respectively. The CHO composition was recorded as high in January 2013 and remained above 25 % during the study period. The calorific contents of the food material (FM) ranged from 1.0 to 6.1 Kcal m−3 (annual average ± SD  =  2.8 ± 1.1 Kcal m−3). Based on a Pearson's correlation coefficient analysis, a major governing factor in the biochemical composition of POM was dissolved inorganic nitrogen loading from the river input in Gwangyang Bay. In conclusion, a relatively larger amount of FM and the higher calorific contents of POM found in this study compared to other regions reflected good nutritive conditions for sustaining productive shellfish and fish populations in Gwangyang Bay. Continuous observations are needed to monitor the marine ecosystem response to potential environmental perturbations in Gwangyang Bay.

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Effects of Behavioral Risk Factors and Social-Environmental Factors on Non-Communicable Diseases in South Korea: A National Survey Approach

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18020612 ◽

2021 ◽

Vol 18 (2) ◽

pp. 612

Author(s):

Nam Jeong Jeong ◽

Eunil Park ◽

Angel P. del Pobil

Keyword(s):

Risk Factors ◽

Environmental Factors ◽

South Korea ◽

Communicable Diseases ◽

Behavioral Risk Factors ◽

Behavioral Risk ◽

Non Communicable Diseases ◽

Path Analyses ◽

Social Environmental ◽

Social Environmental Factors

Non-communicable diseases (NCDs) are one of the major health threats in the world. Thus, identifying the factors that influence NCDs is crucial to monitor and manage diseases. This study investigates the effects of social-environmental and behavioral risk factors on NCDs as well as the effects of social-environmental factors on behavioral risk factors using an integrated research model. This study used a dataset from the 2017 Korea National Health and Nutrition Examination Survey. After filtering incomplete responses, 5462 valid responses remained. Items including one’s social-environmental factors (household income, education level, and region), behavioral factors (alcohol use, tobacco use, and physical activity), and NCDs histories were used for analyses. To develop a comprehensive index of each factor that allows comparison between different concepts, the researchers assigned scores to indicators of the factors and calculated a ratio of the scores. A series of path analyses were conducted to determine the extent of relationships among NCDs and risk factors. The results showed that social-environmental factors have notable effects on stroke, myocardial infarction, angina, diabetes, and gastric, liver, colon, lung, and thyroid cancers. The results indicate that the effects of social-environmental and behavioral risk factors on NCDs vary across the different types of diseases. The effects of social-environmental factors and behavioral risk factors significantly affected NCDs. However, the effect of social-environmental factors on behavioral risk factors was not supported. Furthermore, social-environmental factors and behavioral risk factors affect NCDs in a similar way. However, the effects of behavioral risk factors were smaller than those of social-environmental factors. The current research suggests taking a comprehensive view of risk factors to further understand the antecedents of NCDs in South Korea.

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Temporal and Spatial Variations of the Biochemical Composition of Phytoplankton and Potential Food Material (FM) in Jaran Bay, South Korea

Water ◽

10.3390/w12113093 ◽

2020 ◽

Vol 12 (11) ◽

pp. 3093

Author(s):

Jae Hyung Lee ◽

Won-Chan Lee ◽

Hyung Chul Kim ◽

Naeun Jo ◽

Kwanwoo Kim ◽

...

Keyword(s):

South Korea ◽

Food Source ◽

Coastal Region ◽

Controlling Factors ◽

Spatial Variations ◽

Nutrient Concentrations ◽

Food Material ◽

Biochemical Component ◽

Phytoplankton Communities ◽

Biochemical Compositions

Food material (FM) derived from biochemical components (e.g., proteins, lipids, and carbohydrates) of phytoplankton can provide important quantitative and qualitative information of the food available to filter-feeding animals. The main objective of this study was to observe the seasonal and spatial variations of the biochemical compositions of phytoplankton and to identify the major controlling factors of FM as a primary food source in Jaran Bay, a large shellfish aquaculture site in South Korea. Based on monthly sampling conducted during 2016, significant monthly variations in the depth-integrated concentrations of major inorganic nutrients and chlorophyll a within the euphotic water column and a predominance (49.9 ± 18.7%) of micro-sized phytoplankton (>20 μm) were observed in Jaran Bay. Carbohydrates were the dominant biochemical component (51.8 ± 8.7%), followed by lipids (27.3 ± 3.8%) and proteins (20.9 ± 7.4%), during the study period. The biochemical compositions and average monthly FM levels (411.7 ± 93.0 mg m−3) in Jaran Bay were not consistent among different bays in the southern coastal region of South Korea, possibly due to differences in controlling factors, such as environmental and biological factors. According to the results from multiple linear regression, the variations in FM could be explained by the relatively large phytoplankton and the P* (PO43− − 1/16 × NO3−) and NH4+ concentrations in Jaran Bay. The macromolecular compositions and FM, as alternatives food source materials, should be monitored in Jaran Bay due to recent changes in nutrient concentrations and phytoplankton communities.

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Polychlorinated biphenyls (PCBs) in a benthic ecosystem in Gwangyang Bay, South Korea

Marine Pollution Bulletin ◽

10.1016/j.marpolbul.2011.09.005 ◽

2011 ◽

Vol 62 (12) ◽

pp. 2863-2868 ◽

Cited By ~ 13

Author(s):

Sang Hee Hong ◽

Narayanan Kannan ◽

Un Hyuk Yim ◽

Jin-Woo Choi ◽

Won Joon Shim

Keyword(s):

South Korea ◽

Polychlorinated Biphenyls ◽

Gwangyang Bay

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Relational Aggression During Adolescence: A Systematic Review of Personal and Environmental Factors from Published Articles in South Korea

The Korean Journal of the Human Development ◽

10.15284/kjhd.2021.28.1.93 ◽

2021 ◽

Vol 28 (1) ◽

pp. 93-117

Author(s):

Sungmin Park ◽

Jungha Lim

Keyword(s):

Systematic Review ◽

Environmental Factors ◽

South Korea ◽

Relational Aggression

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Distribution Patterns of Odonate Assemblages in Relation to Environmental Variables in Streams of South Korea

Insects ◽

10.3390/insects9040152 ◽

2018 ◽

Vol 9 (4) ◽

pp. 152 ◽

Cited By ~ 4

Author(s):

Da-Yeong Lee ◽

Dae-Seong Lee ◽

Mi-Jung Bae ◽

Soon-Jin Hwang ◽

Seong-Yu Noh ◽

...

Keyword(s):

Land Use ◽

Ecosystem Services ◽

Environmental Factors ◽

South Korea ◽

Habitat Heterogeneity ◽

Environmental Variables ◽

Environmental Changes ◽

Distribution Patterns ◽

Self Organizing Map ◽

Factors Affecting

Odonata species are sensitive to environmental changes, particularly those caused by humans, and provide valuable ecosystem services as intermediate predators in food webs. We aimed: (i) to investigate the distribution patterns of Odonata in streams on a nationwide scale across South Korea; (ii) to evaluate the relationships between the distribution patterns of odonates and their environmental conditions; and (iii) to identify indicator species and the most significant environmental factors affecting their distributions. Samples were collected from 965 sampling sites in streams across South Korea. We also measured 34 environmental variables grouped into six categories: geography, meteorology, land use, substrate composition, hydrology, and physicochemistry. A total of 83 taxa belonging to 10 families of Odonata were recorded in the dataset. Among them, eight species displayed high abundances and incidences. Self-organizing map (SOM) classified sampling sites into seven clusters (A–G) which could be divided into two distinct groups (A–C and D–G) according to the similarities of their odonate assemblages. Clusters A–C were characterized by members of the suborder Anisoptera, whereas clusters D–G were characterized by the suborder Zygoptera. Non-metric multidimensional scaling (NMDS) identified forest (%), altitude, and cobble (%) in substrata as the most influential environmental factors determining odonate assemblage compositions. Our results emphasize the importance of habitat heterogeneity by demonstrating its effect on odonate assemblages.

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