• Journal of Environmental Science International
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• v.2 no.4
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• pp.291-297
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• 1993

The COD values and chloride ion concentrations of the Taewha river flowing through Ulsan area were determined along the main stream and the relationships between CODs and chloride ion concentrations were described. The results showed that the middle-upper stream and downstream of the Taewha river were polluted deeply with municipal sewage and self-purification occured in the middle-downstream of the river. When domestic sewage is a main source of pollutants, and is especially the only source of chloride in the stream water, the ratio of COD/[$\textrm{Cl}^{-}$] will be utilizable as a measure of self-purification of the stream.

• Korean Journal of Microbiology
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• v.49 no.1
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• pp.30-37
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• 2013

This study was carried out to assess the spatial and tidal effects on the water quality in the lower reaches of Taewha River, Ulsan, Korea and to understand the environmental factors affecting winter algal bloom in the river. From May, 2010 to January, 2011, water samples were collected at five locations (New Samho Bridge, Old Samho Bridge, Mungjung Stream, Taewha Bridge, and Mungchon Bridge) along the river at high and low tides of spring tide. We measured environmental parameters including salinity, dissolved oxygen (DO), biological oxygen demand (BOD), chemical oxygen demand (COD), chlorophyll a (Chl a) and various nutrient concentrations. Salinity increased towards the downstream direction. Average values of Chl a concentrations ranged $10-26mg/m^3$ at high tide and $11-53mg/m^3$ at low tide depending on sampling locations. It was noteworthy that there were strong increases in Chl a concentrations during the November 21 to December 22 sampling period especially at the Taewha Bridge. At the location, Chl a concentrations were measured as $138-296mg/m^3$ for the period; Rhodomonas lacustris of class Cryptophyceae was the dominant algal species. Chl a concentrations at the Taewha Bridge were positively correlated with such parameters as salinity, BOD, DO, COD, pH, and T-N, and negatively correlated with temperature and $NO_3{^-}$-N. On the other hand, at the Mungchon Bridge the highest concentration of Chl a was $55mg/m^3$ on August 25, and Chl a concentrations were positively correlated with $NH_3$-N, T-N, $PO_4{^{3-}}$-P, T-P, and heterotrophic plate counts. The results suggested that water quality in the lower Taewha River fluctuated a lot with the sampling locations and the patterns of algal blooms were different between Taewha Bridge and Mungchon Bridge sampling locations.

• Journal of the Korean Institute of Rural Architecture
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• v.16 no.1
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• pp.53-61
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• 2014

The purpose of this study is to analyze present condition and users' behavior on waterfront in local city. To analyze the current physical statues and behavioral issues, 3 cities including Jinju city(Nam river), Ulsan city(Taewha river), and Dae-gu city(Gumho river) has chosen as research areas, the questionnaire and field survey were conducted in research areas focusing on post occupancy evaluation. In this study, it was found that main behaviors of waterfront were rest and exercise and overall satisfactions of waterfront were related to the decision-making for revisitation. However, unsatisfactory physical factors of waterfront were the position and number of facilities related to the behaviors such as rest, exercise, and bicycle riding. Especially, most unsatisfactory factor was the inadequate lighting in respect of intensity of illumination and position although much people had been used each waterfronts at nighttime. In conclusion it was thought that it was necessary to reinforce the program related to culture and leisure such as public performance and to establish infrastructure related to life-time sport and various outdoor exercise for waterfront activation.

• Parasites, Hosts and Diseases
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• v.26 no.4
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• pp.263-274
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• 1988

Recent patterns of infection with digenetic larval trematodes in fresh- water and brackish-water ask were studied in three locations of the river Taewha during the period from April to October, 1988, and compared with the data reported previously in the same river, 0(16 species of fish examined, the encysted larvae of Cyathocotyle orientalis were found most frequently from 9 species of fresh.water fish. The metacercariae of Echinochasmus sp. , Metacercaria hasegawai and Metagonimus yokogawai were found from 8 species, those of Clonorchis sinensis from 7 species, and Exorchis oviformis and Metorchis orientalis from 5 species of fish. The infection rates of fish with C. sinensis metacercariae were not lower than those reported in 1980, whereas their intensity of infection was found lowered in 3 species, Ccreobagrus brevicorpus, Gnathopogon atromaculatus, and Funtungia herzi. The infection rates of 3 species of fish with M. yokogawai metacercariae were lower than the results in 1982, while the rate was higher in 2 species, Zacco platypus, and Z. temmincki, and rather stationary in Flecoglossus altivelis. The intensity of infection in several species of fish appeared rather higher than in 1980. The encysted larvae of C. orientalis, Echinochasmus sp., E. oviformis and Metacercaria hasegawai showed variations in infection rates of fish in 1980 and in the present study. It was found that the rate of infection with digenetic larval trematodes in fresh- water fish was still relatively high in the river Taewha, and the metacercarial burden in the fish varied greatly by different fish in 1980 and in the present study.

• Journal of The Geomorphological Association of Korea
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• v.23 no.1
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• pp.61-75
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• 2016

This study aims to reconstruct sea level change and paleogeomorphology since the middle Holocene by diatom analysis and 14C-dating from the sedimentary facies of three trenches on alluvial plain of Taehwa River, Taehwa-dong, Ulsan-si, South Korea. The Taewha-dong area was a narrow bay located between Bangeojin and eatuary of Taehwa River was a narrow bay which has been detached from the open sea during middle Holocene. Taewa-dong area at bay area was developed into alluvial plain by the sediments had been come from the Taewa river basin. The sea level change during the middle Holocene effected on the development of Taewha-dong alluvial plain and its information is included in the sediment facies.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.1
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• pp.65-70
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• 1979

The fish faeona of the Hyeongsan River was found to be as follows; 1. The study of fish fauna for this paper was achieved from May to August in 1978. 2. The collected cyprinid fishes from the Hyeongsan River are 13 species in 10 genera, i. e., Cyprinus carpio, Carassius auratus, Gnathopogon coreanus, Gnathopogon majimae, Pseudorasbora parve, Pungtungia herzi, Moroco oxycephalus, Moroco lagewskii, Triboledon hakenensis, Zacco platypus, Zacco temmincki, Rhodeus ocellatus and Pseudoperilampus uyekii. 3. Among them the 5 species, Pseudorasbora parva, Moroco oxycephalus, Zacco platypus, Rhodeus ocellatue and Pseudoperilampus uyekii, are first described from this river. 4. Zacco temmincki is a dominant species in the whole river and Moroco oxycephalus at the upper, Zacco temmincki at the middle and Carassius auratus at the lower part of the river are dominant species in each studied area. 5. The number of distributed cyprinid species in this river compared to the adjacent river basins is $43.3\%$ of the whole Nakdong River and $118.2\%$ of the Taewha River.

• Journal of Environmental Science International
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• v.16 no.5
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• pp.649-655
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• 2007

This study was focused on estimating instream flow, and its optimal alternative for securing the required total amount of instream flow was also researched in order to restore ecosystems and riverine aesthetics of the Mugeo Stream. the first tributary of the Taewha River flowing through the center of Ulsan. In this study the hydraulic and hydrologic conditions and water quality were investigated at specific channel reaches and representative stations of the Mugeo Stream to determine a proper estimate of instream flow. And riverine functions, such as the minimum flow, water duality conservation, fish habitat, and recreation, were considered to restore the environmental functions of the stream, As a result, the total amount of $11,500m^3/day$ was set as the target instream flow for the Mugeo Stream. It was chosen as the optimal alternative for securing the total external supply of $10,000m^3/day$ which have to be transfered from the riverbed flow diverted through the Taewha Main river at upstream of Samho bridge. The water duality throughout the Mugeo Stream channels will be improved considerably to 3-4 mg/l of BOD standard if the target instream flow is supplied and sewage is intercepted by the sanitary sewage system.

• Korean Journal of Environmental Biology
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• v.28 no.3
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• pp.143-149
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• 2010

The pathogens and community structure of the fishes in Taehwa river were investigated from March 2007 to January 2009. During the study period, 3,504 individuals belonging to 35 species, 17 families and 9 orders were collected. The numerically dominant and subdominat species were Opsarichthys uncirostris (relative abundance 39.7%) and Hemibarbus labeo (relative abundance 30.9%). There were five Korean endemic species (20.8%) including Squalidus chankaensis tsuchigae, Zacco koreanus, Cobitis hankugensis, Coreoperca herzi, Odontobutis platycephala. The large fishes like Hemibarbus labeo or Opsarichthys uncirostris were gathered around the Samho bridge, sampling site 2 according to a season. The reaction to which two kinds of fish pathogenic virus is all negative and no fish pathogenic bacteria was isolated from 220 individuals. The fish pathogenic parasite not present variously with 7 species. Especially, Trichodina sp. was detected monthly and the infective density was high. But it is cosidered that temporary overcrowding of fish is not influenced mass mortality causing diseases in the specific site of river.

• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.1
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• pp.56-70
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• 2017

In this study, multi-image information for the central Taewha River basin was used to develop and analyze a distribution map of non-point pollution sources. The data were collected using a hyper-sensor (image), aerial photography, and a field spectro-radiometer. An image correction process was performed for each image to develop an ortho-image. In addition, the spectra from the field spectro-radiometer measurements were analyzed for each classification to create land cover and distribution maps of non-point pollutant sources. In the western region of the Taewha River basin, where most of the forest and agricultural land is distributed, the distribution map showed generated loads for BOD($kg/km^2{\times}day$) of 1.0 - 2.3, for TN($kg/km^2{\times}day$) of 0.06 - 9.44, and for TP($kg/km^2{\times}day$) of 0.03 - 0.24, which were low load distributions. In the eastern region where urbanization is in progress, the BOD, TN, and TP were 85.9, 13.69, and 2.76, respectively and these showed relatively high load distributions when the land use was classified by plot.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.3
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• pp.274-294
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• 2007

The most reasonable method of counting the number of the estuaries in Korea may be counting the number of streams flowing into the sea. The number counting of the streams should be carried out based on the river classes (National River, Regional 1st Class River and Regional 2nd Class River) given by the River Act. The National River scale estuaries are totaled to thirteen, i.e. Han River(including Imjin River), Anseongcheon, Sapgyocheon, Geum River, Mankyeong River, Dongjin River, Yeoungsan River, Tamjin River, Seomjin River, Gawhacheon, Nakdong River(including West Nakdong River), Taewha River, and Hyeongsan River estuaries. The Regional 1st Class River scale estuaries are counted as four, i.e. Yeoungdeok Osipcheon, Samcheok Osipcheon, Gangneung Namdaecheon, and Yangyang Namdaecheon. While, the Regional 2nd Class River estuaries are arranged as the Province and counted as total 444; Jeonnam, Gyeongnam, Chungnam, Jeju Province have the 108, 94, 52, and 35 estuaries, respectively. The counted estuary numbers, however, can be slightly increased/decreased on what references are applied, e.g. whether or not including the streams lost estuary functions by the sea-dike construction or integrated nearby streams, and so on.