• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.4
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• pp.426-434
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• 2018

We investigated temporal and depth-related variation in species composition and abundance of the fish assemblage in the southern East Sea. Fish samples were collected seasonally between 2007 and 2008 using a demersal trawl off the southern coast of Korea. We identified 59 fish species belonging to 41 families. The most frequently occurring species was Coelorinchus multispinulosus, followed by Lophius litulon, Acropoma japonicum and Apogon lineatus. The five most abundant species were A. lineatus, A. japonicum, Myctophum nitidulum, Engraulis japonicus and C. multispinulosus, accounting for 87.04% of the total number of individuals collected. The number of species, abundance and diversity fluctuated with sampling location and time. Permutational multivariate analyses of variance revealed that the assemblage structure was influenced by year, season and water depth, with season being the main indicator. These changes were visually emphasized using non-metric multidimensional scaling ordination plots. Fluctuations in assemblage structure were due to differential contributions of the dominant species.

• Animal Systematics, Evolution and Diversity
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• v.26 no.2
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• pp.105-114
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• 2010

A study of Han River fish assemblage dynamics for 4 years was conducted. From April 2005 to August, 2008, fishes inhabiting two sites of Han River were sampled for identification. For further analysis, 40 individuals of the dominant species were sampled monthly from March 2006 to November 2008. The fish assemblage at site 1 was dominated by Zacco platypus (32.69%), while the subdominant species were Acheilognathus yamatsutae (14.4%), Acanthorhodeus gracilis (9.43%), Squalidus japonicus coreanus (6.84%), and Tridentiger brevispinis (5.18%). The most abundant species at site 2 was Korean Chub (Zacco koreanus) with relative abundance of 62.45% and followed by Pungtungia herzi (10.29%), Coreoperca herzi (8.67%), and Coreoleuciscus splendidus (6.82%) as the subdominant species. At both sites, the endemics populations show an increasing pattern during the whole survey period, while the natives were declining in the last two years.

• 한국해양학회지
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• v.27 no.1
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• pp.46-54
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• 1992

An investigation on the benthic polychaete community in Youngil Bay was conducted during four seasons of 1991. Polychaetes. the dominant macrofaunal group occupying 71.3% in total macro-faunal density, comprised a total of 72 species with a mean density of 1,485 indiv. m/SUP -2/. The highest species number of 54 spp. and density of 3,207 undiv. m/SUP -2/ was recorded in summer, while the lowest in autumn. The most abundant species was Spiophanes nombyx (37.5%), followed by Pseudopolydora sp.(8.4%), Lumbrineris longifolia(7.0%), Madden cristata(6.5%), Polydora ciliata(4.9%) and so on. Maldane cristata was dominated in winter, Polydora ciliata in spring and Spiophanes bombyx in summer and autumn. The density and species number of Polychaetes were high in the southeastern area of Youngil Bay, and poor near the mouth of Hyoungsan River. Based on the species composition, study area was divided into three regions. Each region sustained its specific benthic faunal assemblage; Maldane-Praxillella assemblage from the middle to the southeastern region of Youngil Bay, Spiophanes-Nephtys assemblage in the northwestern region, and Pseudopolydora-Polydora-Capitella assemblage from the mouth of Hyoungsan River to Pohang Hobour. Maldane Praxillella assemblage showed the highest species number of 55 spp.. and the highest species diversity and species richness indices. Spiophanes-Nephtys assemblage had the highest density of 2,675 indiv. m/SUP -2/ and the highest dominance index because of the predominance of Spiophanes bombyx with a density of 2,073 indiv. m/SUP -2/. Pseudopolydora-Polydora-Capitella assemblage was found in the polluted area and it was a specific assemblage mainly composed of the dominance of organic pollution indicator species. The dominant Polychaetes were Pseudopolydora sp., Polydora ciliata, Capitella capitata, and Dorvillea sp.

• The Korean Journal of Quaternary Research
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• v.31 no.2
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• pp.1-12
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• 2017

A total of 23 specimens were collected from the trench sections of the archaeological area, around Yongseong-ri, Buryang-myeon, Gimje. The diatoms identified to 61 species belonging to 32 genera and species diversity and abundance were very few. Three diatom assemblage zones were set up according to the vertical assemblage of each horizons, the absolute abundance of diatoms and the distribution of indicator species. In diatom assemblage zone I, marine species was mainly occurred. Because the marine species is not reported in study of the adjacent area, it is valuable data on sea-water inflow. In diatom assemblage zone II, the yield of brackish and freshwater species are abundant, indicating that the brackish water environment was caused by the influx of freshwater. In diatom assemblage zone III, the yield of freshwater species is high and species of genus Eunotia are mainly occurred. It is considered that they are deposited in wet soil environment where freshwater inflows occasionally.

• Journal of Ecology and Environment
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• v.42 no.4
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• pp.265-271
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• 2018

Background: Temperature-driven variation in pollinator assemblage and activity are important information, especially at high altitudes, where rising temperature trends exceed global levels. Temporal patterns of pollinators in a flowering season can be used as a proxy to predict the changes of high-altitude plants' mutualistic relationships. We observed a spring temperature change in one population of a high-altitude endemic species, Megaleranthis saniculifolia on Mt. Sobaeksan, and related it to pollinator assemblage and activity changes. Methods: This study was conducted at two sites, each facing different slopes (NE and NW), for two times in the spring of 2013 (early-flowering, April 27-28, vs. mid-flowering, May 7-8, 2013). We confirmed that the two sites were comparable in snowmelt regime, composition of flowering plants, and flower density, which could affect pollinator assemblage and activity. Pollinator assemblage and activity were investigated at three quadrats ($1m^2$ with 5-m distance) for each site, covering a total of 840 min observation for each site. We analyzed correlations between the temperature and visitation frequency. Results: Twelve pollinator species belonging to four orders were observed for M. saniculifolia at both sites during early- and mid-flowering times. Diptera (five species) and hymenopteran species (four species) were the most abundant pollinators. Pollinator richness increased at both sites toward the mid-flowering time [early vs. mid = 7 (NE) and 3 (NW) vs. 9 (NE) and 5 (NW)]. Compared to the early-flowering time, visitation frequency showed a fourfold increase in the mid-flowering time. With the progression of spring, major pollinators changed from flies to bees. Upon using data pooled over both sites and flowering times, hourly visitation frequency was strongly positively correlated with hourly mean air temperature. Conclusions: The spring temperature change over a relatively brief flowering period of M. saniculifolia at high altitudes can alter pollinator assemblages through pollinator dominance and visitation frequency changes. Thus, this study emphasizes information on intra- and inter-annual variations in the mutualistic relationship between pollinators and M. saniculifolia to further assess the warming impacts on M. saniculifolia's reproductive fitness.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.4
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• pp.366-379
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• 2002

The monthly collected fish samples by three sides tyke nets were analyzed in order to study species composition and seasonal variation of fish assemblage in the coastal water off Gadeok-do, Korea through a year of 1998, During the study period, a total of 136 fish species of 69 families were collected. Trachums japonicus, Konosims punctatus and Mugil cephaus were three dominant species in the fish assemblage and they accounted for $63.7\%$ and $83.1\%$ in the number of individuals and biomass, respectively. Fish species of secondary importance in abundance were Leiognathus nuchalis, Takifugu niphobles, Somber japonious, Trichiurus lepturus, Chelon affinis, Apogon lineatus, Nibea aibiflora and Acanthopagrus schlegeli. The highest number of species was collected in July and the lowest in february. Abundance was high in spring, and low in winter. Species diversity indices showed that the fish assemblage was less diverse in spring than any other seasons.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.6
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• pp.693-704
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• 2010

Seasonal variation in species composition around Dokdo, East Sea of Korea, was investigated using trammel-net catches, from 2006 to 2009. A total of 53 fish species belonging to 23 families in 12 orders were captured; the orders Perciformes (12 families, 22 species) and Scorpaeniformes (four families, 22 species) were dominant. Between 2008 and 2009, 43 species were collected by trammel net. The number of species was highest in August 2009 (25 species) and lowest in February 2009 (11 species). The number of individuals and total biomass peaked in November 2009. Diversity indices for fish catches were highest in August 2008 (2.4368) and lowest in November 2009 (0.4253). The dominant species were Thamnaconus modestus and Sebastes schlegeli. Hierarchical clustering analysis showed five fish groups, with frequency and number of individuals similar to results of correspondence analysis (CA), which showed a closer relationship to the year term than the season term. CA showed that temperature was an important factor influencing fish species richness and abundance. Three main fish assemblage types coexisted around Dokdo: an East Sea coastal fish assemblage, a subtropical fish assemblage, and a cold water fish assemblage.

• Animal Systematics, Evolution and Diversity
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• v.29 no.2
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• pp.99-114
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• 2013

Phylogeographic and feeding ecological studies of seven terrestrial mustelid species (Carnivora, Mustelidae), the Japanese marten Martes melampus, the sable Martes zibellina, the Japanese badger Meles anakuma, the ermine or the stoat Mustela erminea, the Japanese weasel Mustela itatsi, the least weasel Mustela nivalis, and the Siberian weasel Mustela sibirica, representing four biogeographic patterns in the Japanese archipelagos (Hokkaido, Honshu-Shikoku-Kyushu, Tsushima, and Hokkaido-Honshu), were reviewed in order to clarify causes for the faunal assemblage processes of those mustelid species in Japan. Here, three main constraints were extracted as important factors on the mustelid assemblage. First, fundamental evolutionary differences maintained by niche conservatism in each ecologically diversified lineage ("evolutionary constraint") would enable the species to co-occur without any major problem (coexistence among Martes, Meles, and Mustela species). Second, "ecological constraints" would force two closely related species to be allopatric by competitive exclusion (Mu. itatsi and Mu. sibirica) or to be sympatric by resource partitions (Mu. erminea and Mu. nivalis). Third and most importantly, "geological constraints" would allow specific species to be embraced by a particular geographic region, primarily deciding which species co-occurs. The allopatric distribution of two Martes species in Japan would have been established by the strong effect of the geological separation in Tsugaru Strait. Elucidating both phylogeny and ecology of co-existing species in a community assemblage is important to know which species possess distinct lineage and which ecological traits are adapted to local environments, fulfilling the requirement of the field of conservation biology that endemism and adaptation should both be considered. The Japanese archipelagos would, therefore, provide valuable insight into the conservation for small carnivoran species.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.4
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• pp.288-301
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• 2000

The species composition and seasonal variation of fish assemblage in the coastal water off Gadeok-do, Korea were studied using the monthly trawled samlpes through a year of 1998. During the study period, 110 species of fishes from 57 families were collected. Repomucenus valenciennei, Thryssa kammalensis, Leiognathus nuchalis and Zoarces gilli dominated the fish assemblage throughout the year, and were responsible for $ 57.6{\%}$ and $37.2{\%}$ in the number of individuals and biomass, respectively. Fish species of secondary importance in abundance were Sillago japonica, Apogon lineatus, Pholis fangi, Engraulis japonicus, Thryssa adelae, Pho;is nebulosa, Conger myriaster, Liparis tanakai, Acentrogobius pflaumii, Limanda yokohamae, Chaeturichthys hexanema, Erisphex pottii and Cunoglossus abbreviatus. Higher numbers of species were collected in spring and autumn than in summer and winter. Abundance was high in spring and autumn, and low in summer and winter, Species diversity indices showed that the fish assemblage was more diverse in autumn than any other seasons.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.46 no.4
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• pp.335-345
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• 2010

Species composition and seasonal variation of fish assemblage in Sacheon marine ranching, Korea were examined. Sampling was seasonally made by a shrimp trawl from February 2009 to November 2009. A total of 55 species were collected. Of these, five species was dominant species comprising 51.1% of the total number of individuals. Nine species represented 57.3% of the total biomass. While total abundance (number of individuals) was high in spring, total biomass and species richness (number of species) and diversity were high in autumn. Cluster analysis, based on seasonally abundance data of the 21 most common species, showed that the species were separated into 4 different groups. Group A composed of Pholis nebulosa, Pleuronectes yokohamae, Hypodytes rubripinnis, Hexagrammos otakii, Tridentiger trigonocephalus and Paracercis sexfasciata, which were year round residents, group B Congr myriaster, Leiognathus nuchalis, and Platycephalus indicus, which were abundant in autumn, group C Sillago japonica, Pseudaesopia japonica, Zoarces gilli, Pholis fangi, and Pleuronichthys cornutus which were abundant in spring, and group D Sillago sihama, Cociella sp., Johnius grypotus, Cynoglossus joyneri, Cynoglossus robustus, and Pennahia argentata, which were abundant in summer. Principal component analysis revealed that seasonal variation in the fish assemblage was attributed to the abundance of temporal species such as conger and sand smelt fishes, which were abundant in summer, due to seasonal variation of water temperature.