• Korean Journal of Ecology and Environment
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• v.39 no.2 s.116
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• pp.157-166
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• 2006

Characteristics of ichthyofauna and fish community in the Lagoon Gyeongpo, Korea, were investigated from May to October 2005. Total 26 species caught during the period were belonged to 18 families. Dominant species was T. hakonesis (50.7%) and subdominant species was A. flavimaus (25.4%). K. punctatus (11.1%), M. cephalus (6.5%), E. japonicus (1.5%), C. castaneus (1.0%) were also numerous. Total biomass of collected fish was 401.8 kg, and biomass of each species was T, hakonensis 147.0 kg, A. flavimanus 135.8 kg, K. punctatus 85.6 kg and M. cephalus 23.8 kg. Seasonal variation of fish community seems to be related to spawning periods of species. In conclusion, it appeared that the ratio of the primary freshwater species was gradually decreased, while the peripheral freshwater and seawater species were gradually increased when compared to the data obtained from the past with respect to the ichthyofauna of the Lagoon Gyeongpo.

• Korean Journal of Environment and Ecology
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• v.21 no.6
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• pp.506-514
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• 2007

Temporal and spatial distribution of fish community were investigated from September 2006 to April 2007 targeting the lagoon Youngrang, Korea. A total of 32 species belonging to 16 families were collected during the period, among which the species of primary freshwater fish accounted for 11 (34.38%), the species of peripheral freshwater fish for 18 (56.25%), and that of marine fish for 3 (9.38%) in collected fish community. As a result of taking a look at the transitional aspects of community by each surveyed station and period, it was found that when the 'Breaking-sandbar' occurred, there came a change in the composition ratio of the fish species according to their ecological characteristics. In addition, compared with the data obtained in the past with respect to the ichthyofauna of the lagoon Youngrang, it was found that the ratio of the primary freshwater species gradually decreased, while the peripheral freshwater and seawater species gradually increased according to the indraft of seawater. Thus, it was concluded that fish community in the lagoon seemed to go under transition in its spatio-temporal characteristics depending on the 'Breaking- sandbar.'

• Korean Journal of Environment and Ecology
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• v.22 no.6
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• pp.616-624
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• 2008

The ichthyofauna and ecological community analysis in the Dong River, Korea, were investigated from May, 2006 to May, 2007. During the surveyed period, 31 species belonging 9 families were collected. Total of 31 species(primary freshwater: 26 species, peripheral freshwater: 5 species) were found with the primary freshwater fishes being highest. Dominant species was Zacco koreanus(55.73%), and subdominant species was Coreoleuciscus splendidus(7.15%). Also, Microphysogobio longidorsalis (6.12%), Hemibarbus mylodon(4.87%), Iksookimia koreensis(4.49%) were numerous. There were 19 Korean endemic species(61.29%), including Acheilognathus signifer, A. yamatsutae, Pseudopungtungia tenuicorpus, C. splendidus, Squalidus gracilis majimae, H. mylodon. Among them, 1 species was identified as qualifying for possible designation as a natural monument catergory, and 5 species were identified for designation required to protect under a wildlife category. As result of expected number of species according to rarefaction curve, the expected species of the Dong-river ranged from 19(51. 4, 5) to 22(51. 3) and result of similarity analysis ranged from 62.28%(51. 1 and 2) to 84.13%(51. 1 and 5). In conclusions, we could define that the Dong-river has a very good water conditions as habitat of fish, and habitat conditions also are very similar in every survey sites.

• Korean Journal of Ecology and Environment
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• v.42 no.3
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• pp.394-403
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• 2009

The fish fauna and community structures were investigated at 15 stations in the midupper region of the Seomjin River watershed from August in 2008 to April in 2009. During the studying period, 42 species belonging to 11 families were collected. Dominant family in the all sites was Cyprinidae (28 species, relative abundance: 66.7%) during the study. Total of 42 species (primary freshwater: 40 species, peripheral freshwater: 2 species) were found with the primary freshwater fishes being the highest. Dominant species was Zacco platypus (22.3%), and subdominant species was Coreoferea herzi (10.8%). Also, Pseudogobio esocinus (9.0%) and Carassius auratus (5.8%) were numerous. There were 17 Korean endemic species (40.5%), including Rhodeus ocellatus, Acheilgnathus koreensis, A. somjinensis, Coreoleuciscus splendidus and Sarcocheillichthys variegatus wakiyae. Among them, Acheilgnathus somjinensis was identified for designation required to protect under a wildlife category. In conclusion, we could define that the Seomjin River watershed has a very good water conditions as habitat of fish.

• Korean Journal of Ecology and Environment
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• v.40 no.3
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• pp.449-458
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• 2007

Fish community and its temporal-spacial variation in the Lagoon Hwajinpo, Korea were seasonally investigated with different types of fishing gears from November, 2005 to August, 2006. Total 35.812 fishes caught during the period were belonged to 24 families 37 species. Dominant species was H. nipponensis(60.8%), T, hakonensis (19.8%), and K. punctatus (5.5%) ana these species were peripheral freshwater fish. Among 37 species, primary freshwater and seawater fish were 8 species (21.6%), respectively and peripheral freshwater fish were 21 species (56.8%). Total biomass of collected fish was 279.3kg, and biomass of each species was T. hakonensis 152.9 kg, H. nipponensis 40.0 kg, K. punctatus 31.4 kg and C. haematochelius 25.3 kg, respectively. Hence, productivity of the Lagoon Hwajinpo was much higher than those of inland reservoirs. The aspect of community classified by surveyed period was changed according to the 'Breaking-sandbar', but some of peripheral freshwater fish populations made stable community in their life cycle in the lagoon. In conclusion, the Lagoon Hwajinpo seems to be maintained more natural ecosystem better than other lagoons in Korea. Therefore, the findings provide consideration of the management and restoration for this lagoon and others through the continuous observation and monitoring in future.

• Korean Journal of Environment and Ecology
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• v.11 no.1
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• pp.100-110
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• 1997

To clarify the structure and function of ecosystem and establish the method for the conservation of biodiversity and community analysis at Soksacheon and Gyebangcheon, the authors surveyed the aquatic environment and freshwater fish fauna at 13 stations from July, 1995 to June, 1996. Collected 1,908 individuals were belong to 20 Species, 4 Oredr, 1 Suborder, 6 family, 7 Subfamily. The detail results are as follows. 1. It was confirmed that most of the surveyed stations were mountain valley of river type Aa, Ab. River structures were mixed with pebble, sand, rock and water quality of Soksacheon were pH(7.41), [COND.(0.051), TURB.(10.00), DO(8.66), W.T.(15.4)] and Gyebangcheon were pH(7.44), [COND.(0.097), TURB.(21.59), DO(9.35), W.T.(15.4)]. 2. Among them, 18 species were primary freshwater fishes(99.98%) and 2 species of pheripheral freshwater fishes(0.02%). 12 species(60%) of them were endemic species of Korea and they were Moroco kumgangenesis, Microphysogovio longidorsalis, Cobitis rotundicaudata, Misgurnus anguillicaudatus, Coreoleucisus splendidus, Cobitis longicorpus, Oncorhynchus masou ishikawai, Brachymystax lenok, Hemibarbus longirostris, Silurus microdorsalis, Cobitis koreensis koreensis and Hemibarbus mylodon. 3. Dominant species were Moroco kumgangenesis(46.85%) and Zacco temmincki(27.35%).

• Korean Journal of Ecology and Environment
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• v.56 no.1
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• pp.57-69
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• 2023

The objectives of this study were to analyze the fish community structures and distribution characteristics of fisheries resources in the Osip Stream and Wangpi Stream, fishery resources protection areas. For the study, we conducted fish samplings four times in the two streams from April to October 2019. In Osip Stream and Wangpi Stream, we sampled 31 species and 29 species and the dominant species were Zacco platypus (28.6%) and Squalidus multimaculatus(41.7%), respectively. According to the life type of fish species, primary freshwater species were collected 18 species(58.1%) and 21 species(72.4%), and migration fishes were sampled 4 species (12.9%) and 6 species (20.7%) in Osip Stream and Wangpi Stream, respectively. Fisheries resources species showed high relative abundance in June, and the fish biomass was highest in October. As a results of comparing the previous studies with this study, both rivers showed high biodiversity and were found to maintain stable populations of fishes. According to analysis of tolerance guilds, the proportion of tolerant species, based on the number of individuals, was composed of 14.4% and 1.1% in Osip Stream and Wangpi Stream, respectively. This very low ratio of tolerant species confirmed that both streams have very good physiochemical environment conditions. From the above results, it was judged that the fishery resource protection areas of Osip Stream and Wangpi Stream have high ecological function and preservation value. For sustainable use and management of fishery resource protection areas of Osip Stream and Wangpi Stream, it is suggested that biological disturbance management, fish discharge projects considering environmental capacity, efforts to improve the habitat environment, and establishing a fishery resource protection areas management system were necessary as considerations.

• Korean Journal of Ecology and Environment
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• v.56 no.4
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• pp.348-362
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• 2023

This study analyzed the monitoring results of fishways at 16 weirs constructed on four large Rivers to provide data helpful for the operation and management of fishways. The average utilization rate of the fishways at the weirs was confirmed to be 64.9%. When comparing the dominant species in the mainstream and fishway monitoring results, differences were observed in 9 weirs (56.3%). This indicated that the species prevalent in the mainstream were not necessarily the ones most frequently using the fishways. The average number of individuals using the fishways per day was 336. When classifying the fish species using the fishway by life type, 92.3% were primary freshwater fish, and migratory species accounted for only 5.6%. Analysis based on the season of fishway usage revealed that an average or higher number of fish species used the fishways from May to October, with the highest number of individual users occurring from June to August. Between May and July, 80% of the fish species using the fishways were in their spawning period, while during other season, less than 40% were species that move during the spawning period. The fishways that showed a significant alignment between the spawning period and the fishway passage period were Rhinogobius brunneus, Leiocassis nitidus, Squalidus chankaensis tsuchigae, Pseudogobio esocinus, Acheilognathus rhombeus, and Pungtungia herzi, in that order. When comparing the fishway monitoring results of the Gangjeong-Goryeong Weir and the Dalseong Weir with the upper part water level of the weir, both the number of fish species and individuals using the fishway showed positive correlations with the upper part water level of the weir. This suggests that a higher water level of the weir increases the inflow discharge within the fishway, leading to increased use by fish (number of individuals in Gangjeong-Goryeong Weir, P<0.001; number of species in Dalseong Weir, P<0.05). This study summarized and analyzed the results of fishway monitoring at 16 weirs built on four large Rivers, considering fishway efficiency, operation and management, monitoring period, and regulation of water level in the upper part of the weir. It is thought that this will help understand the status of fish use in fishways on large River and aid the construction, operation, and management of fishways in the future.

• Korean Journal of Environmental Biology
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• v.39 no.2
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• pp.195-206
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• 2021

In 2020, South Korea initiated research and development of a longitudinal connectivity evaluation between upstream and downstream based on stream ecosystem health. This study analyzed the migration of upstream and downstream migratory fish species, fish distribution characteristics, trophic guilds, tolerance guilds, and species composition changes from 2015 to 2020 at Songrim weir in Yeongok stream, where the cross-structure of an ice harbor-type fishway for fish movement was recently improved. A total of 5,136 fish, including 36 species, were collected and three major migratory fishes were identified, namely, Tribolodon hakonensis, Plecoglossus altivelis altivelis, and Oncorhynchus keta. According to the comparative analysis before (Pre-I) and after (Post-I) improvement of the fishway, the relative abundance of primary freshwater fish increased in the upstream section, while the number of migratory fishes decreased. The fish species that used the fishway in the Songrim weir were Tribolodon hakonensis (58.4%) and Plecoglossus altivelis altivelis(11.8%). According to the Wilcoxon Signed-Rank Test migratory fish showed a statistically significant difference (p<0.05) in the upstream and downstream, showing a biological improvement effect of the crossstructure. On the other hand, the annual change of migratory fish based on the MannKendall trend test did not significantly increase or decrease (p>0.05). Therefore, in the fish passage improvement project, it is necessary not only for physical, hydrological, and structural tests, but also for pre- and post-biological tests on the use and improvement effect of fishway.

• Korean Journal of Ecology and Environment
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• v.40 no.2
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• pp.303-317
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• 2007

The fish community of small freshwater ecosystems gets easily disturbed by direct or indirect human induced disturbances during the period of urbanization. Urbanization is one of factors that generate changes in stream and influences fish fauna in developed countries. This study was conducted in Busan Metropolitan City from 2001 to 2004. In order to investigate the fish community, the city was divided into 3 parts, eastern, central and western. A total of 3,206 individuals of 46 species from 19 families were collected from 55 sites. The dominant species was Rhynchocypris oxycephalus, whereas Zacco temminckii was the subdominant species. Cluster analysis was conducted using primary freshwater fish species collected from each stream. As a result of the analysis, study sites were well differentiated into 3 parts. Two species of Z. temminckii and R. oxycephalus represented the upper part of the stream and Carassius cuvieri, Acheilognathus rhombeus, Hemiculter eigenmanni and Micropterus salmoides represented the middle and lower parts of the stream. When compared with previous studies, fish community of the eastern part of the Busan city where urbanization is in progress, showed similar patterns to the central part. At the time of the habitat restoration of fish fauna in stream, appropriate selection of fish species should be made through analysis of stream character and biogeographic distribution of fish, and long-term monitoring is also needed for sustaining the management of fish fauna.