• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.4
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• pp.370-379
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• 2007

Short-term variations of phytoplankton community structure in the southeast coastal waters of Korea from July to September in 2006 were investigated with data set of phytoplankton, chemical and physical water properties, and meterological data. A total of 11 sampling sites of 4 different depths (surface, 5 m, 10 m, and bottom) were visited on July 11-14, July 24-26, August 7-10, August 21-24 and September 5-8. We identified 151 species in 63 genera of phytoplankton in which diatoms were the most diverse group composed of 92 species in 37 genera. Dinoflagellates were the second diverse group of 52 species in 22 genera. The other groups include 7 species in 4 genera including Raphidophytes, and Euglenophyta. After rainy season, excessive nutrients from adjacent streams to the stratified water column proliferates Chaetoceros group in July. But biomass of phytoplankton and nutrient concentrations were decreased during the period of a drought in August. However, Chaetoceros was the most dominant genera in all depths of the first, second, third and fifth cruises, except the 4th cruise on August 21-24 when dominant group were dinoflagellates including Gymnodinium spp. and Cochlodinium polykrikoides. The characteristic of phytoplankton community and environment condition during summer 2006 can be summarized as: 1) low concentration of nutrients caused by a long lasting drought in August 2) no summer outbreak of C. polykrikoides because the strength of offshore waters was weak than other years, and 3) Chaetoceros spp. was the dominant species despite short period appearance of dinoflagellates.

• Korean Journal of Ichthyology
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• v.27 no.2
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• pp.116-132
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• 2015

Freshwater fish fauna and community structure were investigated at 44 stations in upper reach of the Nakdong river, Korea from March to October 2014. During the surveyed period 42 species and 4 types belonging to 34 genera and 14 families were collected. In this collection fishes of Cyprinidae were 17 species and 4 types, most numerous possessing 43.2% of all. There were 17 Korean endemic species including Kichulchoia multifasciata, 3 endangered species such as Koreocobitis naktongensis, Lethenteron reissneri and Brachymystax lenok tsinlingensis and 2 exotic species such as Lepomis macrochirus and Micropterus salmoides. Fish species transferred from other native rivers were 9 species including Hemibarbus mylodon, Coreoleuciscus slpendidus Han river type, Opsariichthys uncirostris amurensis, Iksookimia koreensis and Liobagrus andersoni. Dominant species based on the number of individuals was Rhynchocypris oxycephalus (21.44%) and sub-dominant species were Zacco koreanus NE type (18.55%). The community analysis revealed that the structure of fish community in upper reach of the Nakdong river was very stable and diverse in having diversity 1.101, evenness 0.670, dominance 0.400 and species richness 4.454. Fish community was divided into 5 groups based on similarity indices among surveyed stations such as uppermost, upper I, upper II, mid-upper, middle reach group.

• Korean Journal of Ichthyology
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• v.21 no.3
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• pp.177-190
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• 2009

Species composition and abundance of marine organism in the Nakdong River estuary were investigated seasonally from November 2007 to November 2008. During the study period, a total of 169 species, 93 families, and 6 taxa were collected in the study area. Species included were 2 species in Bivalvia, 11 in Cephalopoda, 43 in Crustecea, 8 in Echinodermata, 6 in Gastropoda, and 99 in Pisces. The seasonal dominant species in number of individuals were Acropoma japonicum in autumn, Apogon lineatus in winter, Siphonalia spadicea fuscolineata in spring, and Crangon hakodatei in summer. Dominant species in abundance were Chelidonichthys spinosus in autumn, Liphius litulon in winter and spring, and Raja kenojei in summer. The number of species and their abundance, the species composition, and the diversity indices fluctuated with seasons. The organisms were divided into 17 groups by seasonal variation using a self-organizing map.

• Korean Journal of Ichthyology
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• v.29 no.3
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• pp.205-217
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• 2017

Fauna of freshwater fish and community structure were investigated at 24 stations in the Hoecheon Stream and some adjacent tributaries of the Nakdonggang River, Korea from July 2016 to August 2017. During the period 42 species and 4 types belonging to 32 genera and 11 families were collected. In this collection fishes of Cyprinidae were 24 species and 4 types, most numerous possessing 59.1% of all. There were 16 Korean endemic species including Acheilognathus yamatsutae and Odontobutis platycephala, 3 endangered species such as Pseudobagrus brevicorpus and Koreocobitis naktongensis (rank I) and Culter brevicauda (rank II) and 2 exotic species such as Micropterus salmoides and Lepomis macrochirus. Fish species transferred from other native rivers were 4 species including Opsariichthys uncirostris amurensis, Hemiculter eigenmanni, Odontobutis interrupta and Tridentiger brevispinis. Dominant species was Zacco koreanus NS type (19.2%) and sub-dominant species was Z. platypus R type (16.1%). The structure of fish community in the Hoecheon Stream was very stable and diverse in having diversity 2.91, evenness 0.77, dominance 0.35 and species richness 4.67. Fish community was divided into 4 groups such as upper, middle, midlower and lower reach group based on similarity among surveyed stations.

• Journal of the Korean Society of Marine Environment & Safety
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• v.15 no.3
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• pp.179-185
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• 2009

The species composition and distributional patterns in marine benthic algae at intertidal zone in Masan Bay were investigated seasonally throughout 2007. A total of 42 species, 5 Chlorophyta 8 Phaeophyta and 29 Rhodophyta were recorded, and dominant species were Enteromorpha linza, Ulva pertusa, Sargassum thunbergii, Gelidium amansii, G. divaricatum, Corallina pilulifera, Gracilaria textorii, and Polysiphonia morrowii during study periods. Especially the vertical distribution of dominant algal species was remarkable: U. pertusa and G. divaricatum were dominated in the upper part, E. intestinalis, E. linza, S. thunbergii and G. divaricatum were in the middle part, and U. pertusa, Undaria pinnatiffda, S. thunbergii, G. amansii, G. divaricatum and C. pilulifera mainly occurred in the low part of tidal zone. The numbers of species were different with seasons and stations; Higher number of species was 38 species in winter, whereas 28 species were the lowest in fall. The number of species was higher at stations 4 and 6 Mile the lower value was at stations 1 and 2 than other stations. The spatial distributional patterns of marine benthic algal composition at each station in dendrogram and MDS ordination were due to the differences of local topography and physical characteristics such as currents and water movements.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.48 no.4
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• pp.452-468
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• 2012

Marine organisms were collected by the stow nets and the stow net on boat fisheries from April 2010 to November 2011 in the Han River Estuary and categorized as 126 species, 61 families, and 5 taxa. The species were consisted with 34 in Crustacea, 5 in Cephalopoda, 79 in Pisces, unidentified jellyfishes in Cnidaria, and Finless porpoise in Mammals. The major species were composed of fish and crustaceans in the Han River Estuary. The dominant species in Crustacea were Chinese ditch prawn (Palaemon gravieri), blue crab (Portunus trituberculatus), Ridgetail prawn (Exopalaemon carinicauda), and mantis crab (Oratosquilla oratoria), and those in Pisces were Korean anchovy (Coilia nasus), and Japanese grenadier anchovy (Coilia mystus). The length structures of the six dominant species have more than one mode in the Han River Estuary. It reflects that the species inhibit during a part of and/or whole lifetime in the Han River Estuary where they utilize as spawning and/or nursery grounds. Freshwater fishes were collected from station D where is the closest location to the Han River stream, and their appearances were well matched with the large amount of freshwater discharge due to flood periods. Principal components analysis (PCA) was carried out with species compositions and showed temporal and spatial differences by the variations of species.

• Korean Journal of Environment and Ecology
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• v.21 no.2
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• pp.149-160
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• 2007

This study was performed to clarify general characteristics of the bird community structure within the boundaries of Hallasan National Park. The surveys were made during April 2006 to February 2007, and the birds were identified and the individual number of those birds was counted up to 38 species and 2,323 individuals in total. Among the total 38 species, 27 residents, 6 summer visitors, 2 winter visitors and 8 passage birds were identified by migratory pattern categories. The most dominant species was Corvus macrorhynchos (14.81%), followed by the Hypsipetes amaurotis(12.66%), and the third was Carduelis sinica(10.33%), and next, Corvus corone (8.44%). About 31 species and 1,639 individuals of birds were sighted around Sallok road 1 (A), and 27 species and 693 individuals of birds were spotted around mountain trails (B), Consequently, it was found that [A] area abounds in more birds than [B] area. Species diversity (H') was distributed over the range of $1.34{\sim}2.56$ degrees in view of the surveyed areas by season. The maximum species diversity (2.56) was found in (A) area in the spring, and the minimum species diversity (1.34) was seen in [B] area in the winter. There are different distributional patterns of birds in terms of the altitude. It was also observed that there were differences in weather factors and food resources by the altitude.

• Journal of Life Science
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• v.27 no.4
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• pp.408-416
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• 2017

This research aimed to identify the diversity and the distribution of invasive alien plant species in the metropolitan city of Busan, South Korea. According to our results, we discovered 10 species of invasive alien plants distributed in Busan, demonstrating that this urban area has a high domestic plant diversity. A cluster analysis identified that the dominant communities of Aster pilosus, Lactuca serriola, Ambrosia artemisiifolia, Rumex acetosella and Solanum carolinense were highly similar in species composition. Different species of invasive alien plants tended to occur together in dominant communities, indicating their preference for shared habitats. The most extensively distributed species in Busan were Lactuca serriola (16 districts), followed by Ambrosia artemisiifolia (11 districts), Aster pilosus (11 districts) and Rumex acetosella (10 districts). The administrative districts with the most diverse invasive alien plants were Gangseo-gu (8 species) and Buk-gu (8 species), which are both areas with high human interference and diverse habitats. Additional environmental information was collected for these species' habitats in Busan. The results of this research can be used to assess the current status of invasive alien plants in Busan and can provide basic data useful for effectively controlling and preventing the spread of invasive plants.

• Korean Journal of Environment and Ecology
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• v.23 no.3
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• pp.258-271
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• 2009

Various environmental parameters change and ecological succession often lead to decline of Pinus densiflora forest in Seoul. Due to decline of it, we proposed the ecological management for conserving and improving from decrease of its dominant area on there. We analysed the P. densiflora forest's classification and suggested its ecological management that based on relation to competition between dominant species in the upper tree layer, the presence of competitive species in shrub layer and vegetation management standard. The Pinus densiflora forest types has been classified 6 types by ecological characteristics. The results from categorized its types are following as; 1) Pinus densiflora pure forest type; edaphic climax Pinus densiflora forest(26.1%), Pinus densiflora pure forest(21.5%). 2) the forest of Pinus densiflora and other species that compete with each other type; Pinus densiflora-Quercus mongolica forest(28.0%), Pinus densiflora-Pinus rigida forest(13.1%), Pinus densiflora-Quercus acutissima(4.2%). We conclude that the results in these kind of 4 types; Pinus densiflora pure forest type where possible to maintain the forest by edaphic climax, human trampling damage, vegetation management(e.x. remove the competition species, shrub layers management etc.) are mainly need to negative management. Whereas, the others 4 types; Pinus densiflora and other species(Quercus variabilis, foreign species, naturalized species etc.) that compete with each other types are need to positive management such as manage the same niche competition species, shrub layers management, remove the foreign species, naturalized species etc.. In these kinds of ecological management are very necessary to maintain Pinus densiflora forest.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.6
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• pp.715-722
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• 2002

The monthly collected fish samples by crab pots were analyzed in order to study the species composition and seasonal variation of fish assemblage in the coastal water off Gadeok-do, Korea in 1998, During the study period, 49 species of fishes representing 26 families were collected, The dominant species were Conger myriaster, Sebastes inermis, Hexagrammos otakii, H. agrammus, Stephanolepis cirrhifer and Acanthogobius flavimanus. These 6 dominant species accounted for $67.1\%$ and $69.4\%$ in the number of individuals and biomass, respectively. The secondary importance species were Thamnaconus modestus, Takifugu niphobles, Rudarius ercodes, Dictyosoma burgeri, Sebastes longispinis and Epinephelus septemfasciatus. The highest number of species was collected in November, and the number of individuals and biomass were highest in March. But the lowest numbers of species and individuals were collected in July and the lowest biomass in September, Although the species diversity indices varied little monthly, the lowest value was recorded in August because of small number of species and predominance of 5. cirrhifer and T. modestus.