• Magazine of the Korean Society of Agricultural Engineers
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• v.22 no.2
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• pp.55-63
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• 1980

To study run-off characteristics in the small watersheds in Korea, investigations had been carried out for a period of 4 years from 1972 to 1975 in the sample watersheds. The samples were selected in four major river basins such as the Han River, the Keum River, the Nakdong River and the Yongsan River. Water levels and rainfall data had been. collected from each sample area where the measuring instruments were installed. The findings of this investigation can be summarized as follows; 1. With an average runoff rate of 60% in the sample watersheds, the average runoff rate. in each sample proved to be as below; the Han River Basin : 41.4% the Keum River Basin : 61.7% the Nakdong River Basin : 69.4% the Yong San River Basin : 69.2% 2. The base flow rate in the sample watersheds proved to be 8.1 mm/month. 3. A comparison of the runoff obtained from actual measurements made and that calculated by the Kaijyama formula showed that the latter is 9.1% lower than the former.

• Journal of Korean Port Research
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• v.13 no.1
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• pp.133-146
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• 1999

Mokpo coastal area is connected to the adjacent a long river and two large basins. It is essential for port planning coastal zone management and environmental impact study to analyze the data related to the ship operation and variation of current and water quality due to the development of water area including dredging reclamation and estuary barrage. The Yongsan river estuary weir and Yongam-Kumho basins discharge much of water through water gates for the purpose of flood control and prohibit salt intrusion at the inland fresh water area. To meet this purpose discharge through the gates have been done at the period of maximum water level difference between inner river and sea level. This discharged water may cause the changes of current pattern and other environmental influences in the vicinity and inner area of semi-closed Mokpo harbor. In this study ADI method is applied to the governing equation for the analysis of the changes on current pattern due to discharged water. As the results of this study it is known that the discharging operation causes many changes including the increase of current velocity at the front water area at piers approaching passage and anchorages. Discussion made on the point of problems such as restricted maneuverability and the safety of morred vessels at pier and anchorage. To minimize this influence the linked gate operation discharging warning system and laternative mooring system are recommended.

• Journal of the Korean association of regional geographers
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• v.22 no.4
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• pp.843-855
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• 2016

The objective of this study is to find out geomorphological characteristics of historical ruins where people produced and consumed large jar coffins excavated in the Yeongsan river basin using Fluvio-Marine Plains from detailed soil map. For this purpose, we chose the 21 consumption sites. The results are as follows. 21 consumption sites located in the region of upper limit of tidal internal in Yongsan River and tributary rivers. Among these, 18 Consumption sites has high accessibility with Fluvio-marine plains. This means that Consumption remains of Yongsan River basin have been located to area available for distribution from production sites.

• Proceedings of the Zoological Society Korea Conference
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• 2001.10a
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• pp.156.3-157
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• 2001

No Abstract, See Full Text

• Proceedings of the KGS Conference
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• 2001.05a
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• pp.19-25
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• 2001

• 한국해양학회지
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• v.26 no.2
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• pp.101-107
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• 1991

We report on the seasonal fluctuation of a Poecilostomatoida copepod, Pseudomyicola spinosus associated with the blue mussel, Mytilus galloprovincialis in the Yongsan River estuary (34$^{\circ}$47N, 126$^{\circ}$27'E). P. spinosus has four generations a year, seasonally succeeding each other. The generation that occurs during summer has the highest number of individuals. From June to October with the exception f September, males dominated while female outnumbered from November to May with the exception of January. It is possible to find ovigerous females all year with the exception of February. The largest number of ovigerous females occurs a month earlier than copepodids do. The percentage of C1 to C3 is approximately 4% of the total number of copepodids, indicating that in situ infestation by copepodids mainly occurs in C4 stage.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.04a
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• pp.173-178
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• 2004

Due to the development of Yongsan river estuary weir and Yongam-Kumho sea dike, Mokop coastal area is changed. Especially, Discharged water through Yongsan river estuary weir and Yongam-Kumho sea dike, may cause the environmental influences such as the changes of currents pattern and sedimentation in the vicinity of semi-closed Mokpo harbor. This study deals with the collection and analysis of discharge through estuary weir and sea dike, based on that, we analyzed a characteristics of a sea area from simulation. As the results of this study, it is known that discharge causes the changes of a tidal currents pattern and calculated depth variations showed close relation with tidal circulation.

• Journal of Environmental Science International
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• v.22 no.2
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• pp.215-223
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• 2013

The objective of this study was to evaluate fish passage efficiency, based on fish-trap monitoring methodology, in the fishway of Seungchon Weir, which was constructed on the lower region of Yeongsan River in 2011. Seasonal patterns and diel variations of fish movements, fish fauna, and compositions in the fishway were analyzed in relation to the current velocity and location of the trap-setting in the fishway. For the analysis, we conducted seven times surveys in 2012 on the fishway and also conducted intensive monitoring of the fishway as 3 hrs interval for the diel variations of fish fauna and compositions in the fishway. According to the fish-trap monitoring methodology, the total number of fish species was 13 species, which was a 43.3% of the total. Most dominant fish used the fishway was Squalidus chankaensis tsuchigae and the relative abundance of the species used the fishway was 33.5% of the total. The season and time zone (in diel variation) observed most frequently in the fishway were July and 18:00-21:00 PM, respectively. The fish movements and use-rates of fishway varied depending on the locations of trap-setting; Fish biomass and the number of species were statistically (p < 0.05) greater in the most right or left-sided traps than in the mid-traps. Also, fish movements and use-rates of fishway were influenced by current velocity on the fishway; fish in the fishway preferred the low current velocity (mean 0.71 m/sec) than the high current velocity (mean 1.13 m/sec). Further long-term studies should be monitored for the efficiency evaluations of the fishway.

• The Korean Journal of Ecology
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• v.12 no.1
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• pp.51-65
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• 1989

Some aspects of limno-biology of the five dammed lakes such as Tamyang, Changsong, Kwangju, Naju, and Youngsan Lake along the Yongsan River were investigated from June 1986 to July 1988 for the comparison on the lentic ecosystems in relation to the fish fauna. Sixty four fish species representing 48 genera and 21 families of fishes were collected in these dammed areas, which included 29 species of the family Cyprinidea and 40 speaies of the primary fresh-water fishes. Among, these, 12 species such as Rhodeus Acheilognothus yamatsutae, A canathorhodeus gracilis, Sarcocheilichthys nigripinis morii, S. variegatus wakiyae, Gnathopogon strigatus, Squalidus gracilis majimae, Microphysogobio yaluensis, Cobitis longicorpus sp, Liobagrus mediadiposalis and Odontobutis platycephala are enddmic to Korea. Leiocassis nitidus and Gasterosteus aculeatus which occur in these water areas take note of the zooge rographic study of Korea. The fish species in each of the dammed lakes is in proportion of the scale of the lakes such as 32 species in Thamyang, 40 species in Changsong, 24 species in Kwangju, 35 species in Jaju, and 52 species in Yongsan Lake. The dominant fish species of the 4 upper dammed lakes of Thamyang, Changsong, Kwangju and Naju Lake are Zacco platypus and Rhodeus uyekii, while those of Youngsan Lake are Hemiculter eigenmanni and Carassius auratus. This difference of fish species of those areas suggests that the upper damed lake differ from the lower dammed lakes in the habitable condition of fishes. The migratory fish species have significantly declined and will continue to decline in both population size and number of species in the dammed lakes in near future as a result of the dam construction barriers in the river estuary. The major migratory fishes of this water area are as follows; Anguilla japonica, Plecoglossus altivelis, Hypomesus olidus, Gasterosteus aculeatus, Konosirus Punctatus, Coilia ectens, Hemirhampus sajori, Mugil cephalus. Acanthogobius flavimanus, and Takifugu ocellatus.

• 한국약용작물학회:학술대회논문집
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• 2011.09a
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• pp.390-391
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• 2011