• Korean Journal of Environment and Ecology
• /
• v.21 no.6
• /
• pp.506-514
• /
• 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
• /
• v.22 no.6
• /
• pp.616-624
• /
• 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
• /
• v.39 no.2 s.116
• /
• pp.157-166
• /
• 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 Ecology and Environment
• /
• v.40 no.3
• /
• pp.449-458
• /
• 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 Ecology and Environment
• /
• v.42 no.3
• /
• pp.394-403
• /
• 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
• /
• v.34 no.3 s.95
• /
• pp.251-258
• /
• 2001

The ichthyofauna and passing efficiency of fish ways were surveyed in the lower and upper regions of the river mouth dam in the lower reaches of the Nakdong river from June to December in 20()0. As the dam built in the river mouth, the brackish area in the estuary disappeared completely and the transitional area did not formed. The fishes collected from survey were classified into 49 species, 45 genera belonging to 29 families. Among them, the fresh water fishes composed of 10 species, peripheral freshwater fishes 11 species and sea water fishes 28 species respectively. Because of the ecological difference between the fresh and sea water, dominant species in the Myeong-ji of sea water area was Acanthogobius flavimanus (39.1%) and in the Sa-sang of fresh water area was Achanthorhodeus macropterus (44.4%). By the video camera records, fishes were identified nine species like as Coilia ectenes, Cyprinus carpio, Hemibarbus labeo, Squalidus gracilis majimae, Plecoglosus altivelis, Lateolabrax japonicus, Anguilla japonica, Mugil cephalus and Pholis nebulosa. Based on total species collected, the efficiency of the fish way for the anadromous fish was 10.1%. Therefore, efficiency evaluation of the fish way in the Nakdong River Mouth Dam was low.

• Korean Journal of Environment and Ecology
• /
• v.11 no.1
• /
• pp.100-110
• /
• 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 Ichthyology
• /
• v.10 no.1
• /
• pp.87-97
• /
• 1998

The freshwater fish fauna and distribution were investigated in Kojedo from 1982 to 1997. The collected fishes were classified into twenty four species of ten families. Dominant species was Zacco temmincki (relative abundance: 18.1%) and subdominant species was Rhinogobius brunneus (16.4%). Also Iksookimia longicorpus (12.3%), Oryzias latipes (7.5%), Chaenogobius urotaenia (7.5%) and Carassius auratus (6.9%) were numerous. The endemic species of Korea were six species (25.0%) and endangered species were C. splendidus, S. microdorsalis and C. kawamebari. In this study, species diversity index was high at Yoncho stream, dominance index at Aju and Oaepo stream and evenness index at Oaepo stream in community structure. There was a tendency of fish distribution in Kojedo that more longer the stream and more larger the water volume were, there were more species and more individual numbers. It was considered that the dominance of upper and middle reach dwelling fishes resulted in the dominance of Aa type stream mainly. Liobagrus mediadiposalis and L. mediadiposalis ssp. 1 showed different distribution pattern in Kojedo : that is, the former inhabited in east-northern part but the latter in south-western part separately. And the importance of this distribution pattern was discussed in relation to paleogeography.

• Korean Journal of Environmental Biology
• /
• v.31 no.4
• /
• pp.402-410
• /
• 2013

In this study, to identify ichthyofauna of the Seomjin River, which has no barrage at estuary, and to estimate effect of estuary barrage, fish sampling was conducted at 16 study sites in mainstream of the Seomjin River from 2010 to 2012. A total of 54 species classified into 17 families were collected. Cyprinidae was the dominant family and Zacco platypus (relative abundance, RA: 47.8%) was identified as the dominant species. In total, 17 Korean endemic species (31.5%) were collected, and it is higher than the average endemic rate of Korean peninsula (22.5~25.9%). Although the relative abundance of exotic species (1.1%) was low, it is higher than the past studies (2002: 0.0%, 2009: 0.4%). Dominance index of freshwater region (St.4~St.16) was relatively higher than estuary (St.1~St.3), because Z. platypus showed high relative abundance at freshwater region. But diversity and evenness index showed contradictory results, as estuary was higher than freshwater region. The ratios of sea fish, peripheral freshwater fish and economic fish, and diversity index are higher than the Nakdong River, the Yeongsan River and the Geum River. In conclusion, to conserve the value of the Seomjin River ichthyofauna, continuous monitoring is necessary.

• Korean Journal of Ecology and Environment
• /
• v.52 no.4
• /
• pp.306-315
• /
• 2019

The estuary of the Han River constantly suffers from pollutants and pathogenic microorganisms which could cause serious damage to aquatic organisms living there. Despite of this potential risk, it is hard to find any reliable scientific reports on the status of reportable disease infection to the organisms living in this area. In this study, cyprinid fish and crustaceans in Jeonryu-ri, a region of the Han River estuary, were investigated for the infection by representative reportable communicable diseases(SVC, spring viraemia of carp; KHVD, koi herpesvirus disease; EUS, epizootic ulcerative syndrome; WSD, white spot disease) and parasites. Peripheral fish and primary freshwater fish were observed in Jeonryu-ri with cyprinid caught most frequently. Crustaceans were mostly marine species. No positive bands to any of the reportable diseases were produced in any of the fish and crustacean examined in this study by PCR. No trace of Clonorchis sinensis, a liver fluke potential threat to human health, was detected in any of fish samples. However, many fish were infected by metacecaria of other flukes, and other various parasites such as nematode, cestode, copepod, monosite and acanthocephalan. These results suggest that important aquatic organisms in the Han River estuary is not seriously polluted yet. However, it is important to keep monitoring the diseases since the water quality in this region is constantly changing, and devastating influence of infectious diseases is unpredictable. Further, it is required to expand monitoring area toward upstream and increase the number of fish for examination.