scholarly journals Analysis of the Water Circulation Structure in the Paldang Reservoir, South Korea

2020 ◽  
Vol 10 (19) ◽  
pp. 6822
Author(s):  
Hwangjeong Choi ◽  
Ingu Ryu ◽  
Minji Park ◽  
Yongsik Song ◽  
Soonju Yu ◽  
...  
Keyword(s):  
Water Quality ◽  
South Korea ◽  
Discharge Rate ◽  
Water Circulation ◽  
The South ◽  
Han River ◽  
The North ◽  
Study Results ◽  
Instantaneous Discharge ◽  
Layer Flow

In this study, results are presented for depth-specific hydraulic and water quality surveys, as well as meteorological observations, at key monitoring sites in the Paldang Reservoir, South Korea. These results were used to determine the water circulation characteristics that represent the main contributors to water quality changes. In the section before the confluence point of the two rivers, a different type of two-layer flow appeared for each. In the North Han River, backwater flowing backward in the upstream direction occurred in the surface layer, and was accompanied by two-layer flow, during the zero-discharge period of the Cheongpyeong Dam. On the other hand, in the South Han River, two-layer flow was observed in the upper layer in the downstream flow, and the thickness of upper and lower layers varied depending on the discharge rate of the Paldang Dam. Strong flow fluctuations were observed near the Paldang Dam (3 km upstream), and these were dependent on its instantaneous discharge rate. In particular, if the instantaneous discharge from the Paldang Dam remained below 400 m3/s for several days, the flow velocity in the lower layer decreased below 2 cm/s or no flow occurred. The comparison between flows during different periods associated with depth-specific water temperature variations showed that the average flow prevailed across all layers in the downstream direction at all monitoring sites during the vertical mixing period. In contrast, spatiotemporal variations in flow, such as two-layer flow and backwater, were observed during the stratification period in the South Han River and the North Han River. This led to increased residence times and vertical stability, thus creating favorable conditions for algal blooms.

Modeling the hydrodynamics of a wetland under strong anthropic pressures (Torbiere del Sebino, Italy)

2021 ◽  
Author(s):  
Stella Volpini ◽  
Marco Pilotti ◽  
Giulia Valerio ◽  
Steven C. Chapra
Keyword(s):  
Water Quality ◽  
Specific Conductivity ◽  
Quantitative Information ◽  
Northern Italy ◽  
The South ◽  
The North ◽  
Subalpine Lake ◽  
Ecological Importance ◽  
Set Up ◽  
And Shifts

<p>The Natural Reserve “Torbiere del Sebino” is situated on the southern bank of Lake Iseo and is one the most meaningful wet zone for extension and ecological importance of northern Italy, belonging to the Natura2000 network.</p><p>Torbiere occupies an area of 3.60 km<sup>2</sup> within a 14 km<sup>2</sup> watershed where almost 12000 inhabitants live and where agricultural activities, mostly vineyards, cover almost 40% of the area; this leads to a significant anthropic pressure that over the last 50 years has compromised the system and changed the equilibria between species, enhancing eutrophication.</p><p>Despite the ecological relevance of the area, one of the most important in northern Italy, very little quantitative information is available regarding its current state and evolution in terms of water quality and hydrodynamics.  Given the critical environmental condition of the habitat, it is necessary to address the consequences of human impact on the trophic state of Torbiere.</p><p>Torbiere consists of a system of shallow lakes or ponds (average depth 1.5 m) whose main affluent is a creek (called Rì) entering from the South. A secondary occasional affluent enters the system from the East and consists of a combined sewer overflow (CSO). Finally, the main effluent is an artificial channel located in the North connecting Torbiere directly with the subalpine Lake Iseo. Although originally subdivided into a set of many interconnected ponds, the separation levees have been demolished over the last decades to enhance internal circulation, under the assumption that this would decrease the residence time and improve the water quality. However, no rational argument was used to support this decision that led to a system where similar characteristics (Secchi’s depth, turbidity, specific conductivity) are found all over the study area and where the expansion of invasive species was easier; now there is some evidence that a separate set of ponds would be better manageable to contrast the eutrophication process. To understand this process, a 3D hydrodynamic model has been set up using Delft-3D, an open source, finite difference package. </p><p>Given the great extension of the system, the inner circulation of the water is not driven by the momentum of the affluents, instead the wind plays a major role. This forcing term presents a daily pattern: it blows from the North in the mornings and shifts to the opposite direction in the late afternoon. The water mainly flows from the South to the North. However, preliminary results by Delft 3D showed that the circulation is made complex by the wind. The model shows that opposite directions of horizontal flow velocities are found at the surface and at the bottom of the water column, showing that only the upper layers follow the direction of the wind.</p><p>By comparing the actual and previous conditions of separation of the ponds, the model aims to give an answer to whether the choice of demolishing the banks was positive or negative for the water quality of Torbiere. Once the role of the banks will be clarified, the effects of their possible restoration will be addressed.</p>

Presence and Quantification of Microplastic in Urban Tap-Water

2020 ◽  
Author(s):  
Claudia B. Pratesi ◽  
Maria Aparecida A.L. Santos Almeida ◽  
Geysa S. Cutrim Paz ◽  
Marcelo H. Ramos Teotonio ◽  
Felipe Mendes dos Santos Cardia ◽  
...  
Keyword(s):  
Tap Water ◽  
The South ◽  
Plastic Pollution ◽  
Wing Area ◽  
Health Crisis ◽  
Toxicological Effect ◽  
The North ◽  
Study Results ◽  
The Mean ◽  
Number Of Particles

Abstract Background: Plastic pollution is a rapidly growing environmental and human health crisis, with no sign of improvement. Since 2012 the number of studies on plastic pollution has quadrupled, and macro to nano-size plastics have been documented even in the planet's remote biomes. Studies have shown contamination by microplastics (MPs) in various types of food consumed by humans, including seafood, honey, sugar, salt, tap-water and bottled water and beer. The study's objective was to detect the possible contamination by MPs in drinking water samples collected from the two main residential and commercial areas of Brasília.Methods: A total of 32 samples of tap water were collected, 16 samples in the south zone, and 16 samples in the north zone of the city (respectively, South Wing and North Wing). Samples were processed and transferred to the Sedgewick-Rafter counting cell chamber. The presence of MPs particles was analyzed using a Nikon Eclipse fluorescence microscope.Results: MPs were found in 100% of the samples. The mean MPs per 500 ml found in the South Wing area was 97, while the mean number of particles in the North Wing area was 219.Conclusion: The study results reveal a disturbing amount of MP particles in Brasilia's tap-water. This surprising number of particles in tap-water is especially concerning considering that tap-water is not the only source of MPs to which people are exposed. The cumulative and toxicological effect of this chronic exposure is alarming.

scholarly journals Draft Genome Sequence of Putative 2-Methylisoborneol-Producing Pseudanabaena yagii Strain GIHE-NHR1, Isolated from the North Han River in South Korea

2020 ◽  
Vol 9 (27) ◽  
Author(s):  
Ju-Yong Jeong ◽  
Sang-Hoon Lee ◽  
Mi-Ra Yun ◽  
Seung-Eun Oh ◽  
Tae-Hwa Kim ◽  
...  
Keyword(s):  
South Korea ◽  
Genome Sequence ◽  
Genome Analysis ◽  
Draft Genome ◽  
Draft Genome Sequence ◽  
Filamentous Cyanobacterium ◽  
Comparative Genome Analysis ◽  
Han River ◽  
The North ◽  
Genome Information

ABSTRACT The draft genome sequence of Pseudanabaena yagii GIHE-NHR1, a filamentous cyanobacterium, is reported here. Comparative genome analysis suggests that this strain can produce an odor-causing compound (2-methylisoborneol) in water. The genome information is expected to improve the understanding of the putative 2-methylisoborneol production by the bacterium.

scholarly journals Relationship between Coliform Bacteria and Water Quality Factors at Weir Stations in the Nakdong River, South Korea

Water ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 1171 ◽  
Author(s):  
Mijin Seo ◽  
Haejin Lee ◽  
Yongseok Kim
Keyword(s):  
Water Quality ◽  
Organic Matter ◽  
South Korea ◽  
Influential Factor ◽  
Fecal Coliforms ◽  
Coliform Bacteria ◽  
Quality Factors ◽  
Nakdong River ◽  
Study Results ◽  
The Nakdong River

Artificial structures installed in rivers can change the natural physical, physiochemical, and biological characteristics of the rivers. Coliform bacteria are important water quality indicators, related to human health. This study investigated the relationship between coliform bacteria and water quality factors at eight weir stations constructed in the Nakdong River, a major river in South Korea. Fifteen water quality factors were analyzed at these sites from 2012 to 2016 using correlation and multiple regression analyses. The results for all stations confirmed the analytical validity, with high adjusted R2 values of approximately 0.6 and 0.8 on average for total and fecal coliforms, respectively. The results showed influential water quality factors affecting the concentration of coliform bacteria at weir stations. Specifically, total coliforms were mostly affected by organic matter and fecal coliforms were mostly affected by phosphate phosphorus and suspended solids. Rainfall was the most influential factor affecting both coliforms. Further, both coliforms were negatively affected by organic matter below the Dalseong weir in the mid- to downstream area of the Nakdong River. A positive relationship with phosphate phosphorus was indicated at all weir stations. To the authors’ knowledge, this kind of study has never been attempted so far. Thus, the study results can provide important information on influential water quality factors related to coliform bacteria, especially in the Nakdong River, creating a foundation for future water quality management.

Southeast Asia’s Roles in Inter-Korean Affairs

2019 ◽  
Vol 11 (03) ◽  
pp. 50-58
Author(s):  
Erik MOBRAND ◽  
Hyejin KIM
Keyword(s):  
South Korea ◽  
Southeast Asia ◽  
Korean Peninsula ◽  
The South ◽  
The North ◽  
International Engagement

Southeast Asia’s significance to the Korean peninsula is growing. South Korea has deepening trade, investment and assistance relationships in the region, while ASEAN’s non-judgmental approach to diplomacy is useful in dealing with Pyongyang. Beyond hosting summits between American and North Korean leaders, Southeast Asia is in a position to mediate North Korea’s greater international engagement and to assist in the acceleration of interaction between the North and the South.

Rainfall and Hydrological Comparative Analysis of Water Quality Variability in Euiam Reservoir, the North-Han River, Korea.

2017 ◽  
Vol 50 (1) ◽  
pp. 29-45 ◽  
Author(s):  
Soon-Jin Hwang ◽  
Yeon Bo Sim ◽  
Bong-Geun Choi ◽  
Keonhee Kim ◽  
Chaehong Park ◽  
...  
Keyword(s):  
Water Quality ◽  
Comparative Analysis ◽  
Han River ◽  
The North

Hydro-meteorological Effects on Water Quality Variability in Paldang Reservoir, Confluent Area of the South-Han River-North-Han River-Gyeongan Stream, Korea

2016 ◽  
Vol 49 (4) ◽  
pp. 354-374 ◽  
Author(s):  
Soon-Jin Hwang ◽  
Keonhee Kim ◽  
Chaehong Park ◽  
Wanbum Seo ◽  
Bong-Geun Choi ◽  
...  
Keyword(s):  
Water Quality ◽  
The South ◽  
Han River ◽  
Meteorological Effects

Reconciling Nations and Citizenship: Meaning, Creativity, and the Performance of a North Korean Troupe in South Korea

2016 ◽  
Vol 75 (2) ◽  
pp. 387-409 ◽  
Author(s):  
Sunhee Koo
Keyword(s):  
South Korea ◽  
Performing Arts ◽  
Cultural Hybridity ◽  
The South ◽  
Performance Culture ◽  
The North ◽  
Ethnographic Data ◽  
And Performance ◽  
North And South ◽  
Organization Membership

Since 2000, a number of performing troupes have been established in South Korea, made up largely of musicians and dancers who were professionally trained in North Korea prior to their migration and presenting a range of music and dances related to both the North and South. Combining ethnographic data with performance analysis of one such troupe, the Pyŏngyang Minsok Yesultan, I show how the nation and the state intersect in the space of performing arts as the troupe's creative culture reflects the settlement experiences of North Koreans in the South. While the troupe's organization, membership, and performance culture delineate migrant adaptation and understanding of their new citizenship, the performance of these Koreans is a complex terrain in which the two Koreas converge and are contested as the performers enact a constant negotiation between “being” and “negating” North Korean-ness, expressing their cultural hybridity as emergent citizens of the South.

6. Globalizing south, inward north

2020 ◽  
pp. 107-126
Author(s):  
Michael J. Seth
Keyword(s):  
South Korea ◽  
North Korea ◽  
Democratic Society ◽  
The Political ◽  
Consumer Society ◽  
Political Systems ◽  
The South ◽  
The North ◽  
Economic Stagnation

‘Globalizing south, inward north’ shows that from the 1980s the two Koreas grew further apart, economically, politically, and culturally. Few states moved faster from poverty to ‘developed’ status than South Korea, none developed a more totalitarian, isolated society than North Korea. South Korea’s economy expanded impressively well into the 2000s, becoming a wealthy consumer society, while North Korea went through economic stagnation and decline. Both started with authoritarian political systems; however, the South evolved into an open, democratic society while the North remained authoritarian and closed. Most Koreans continued to see themselves as part of one nation united by common ethnicity and ancestry, and regarded the political division as unnatural and unacceptable. Is reunification possible?

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