• 한국수산과학회지
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• 제55권2호
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• pp.154-170
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• 2022

The zooplankton composition, abundance, community structure, and species diversity in the major commercial fishery species spawning grounds in the southern coast of Korea were investigated in this study. A total of 80 taxa were sampled, with the mean abundance range of 5,612-11,720 ind. m^-3 and the mean biomass range of 41.6-1,086.8 mg m^-3. The dominant species were Paracalanus copepodites, Paracalanus parvus s. l., Oithona copepodites, Paracalanus nauplii, Noctiluca scintillans, Oithona similis, and Ditrichocorycaeus affinis. The species diversity indices were highest in August, suggesting that diversity is influenced by neritic and oceanic warm-water species. A cluster analysis with non-metric multidimensional scaling (nMDS) revealed three groups of zooplankton communities. The April and May samples clustered into Group A, having the highest mean total zooplankton abundance and lowest species diversity, consisting mainly of temperate species located in the middle region of the southern coast of Korea. Cluster Group B was from the early summer season (June) and contained the highest species diversity with some oceanic and neritic zooplankton species. Cluster Group C from the summer season (July and August) mainly comprised P. parvus s. l. and O. similis. The redundancy analysis (RDA) indicated that abundance is positively correlated with salinity, and chlorophyll-a concentrations.

• 한국수산과학회지
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• 제33권3호
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• pp.243-249
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• 2000

1998년 1월에서 12월 사이 월별로 경남 진해시 용원의 천해역에서 지인망으로 어류를 채집하여 계절에 따른 종조성을 분석하였다. 총 34종의 어류가 채집되었으며, 줄공치 Hyporhamphus intermedius의 유어, 날개망둑 Favonigobius gymnauchen과 미끈날망둑 Chaenogobius laevis 같은 망둑어류, 그리고 베도라치 Pholis nebulosa와 같은 주거종이 $8{\~}10$월을 제외한 시기에 우점하였다. 난수기에는 밴댕이 Sardinella zunasi,주둥치 Leiognathus nuchalis, 복섬 Takifugu niphobles와 같은 연안성 부어류들이 출현하였으나 종수와 채집량이 적었다. 평균 생물량은 322 마리/1000 $m^2,\;806 g/1000\;m^2$로, 서해 천수만의 펄질 천해역보다 평균 개체수가 적었고, 대천 모래질 쇄파대보다는 높았다. 생물량은 11월에서 1월 사이 줄공치가 대량 채집되어 높았고, 2월부터는 주거종이 증가하고 4월부터 일시 출현종이 유입되어 6월까지 비교적 높은 출현종 수와 생물량을 보였다. 그러나, 수온이 높은 8월에서 10월 사이에는 일시 출현종 만이 소수 출현하여 출현종수와 생물량이 낮았다. 조사해역은 조간대 하부가 얕은 펄질로 해수 순환이 미약하여 수온이 높은 계절에는 수질이 어류의 서식에 부적합할 것으로 추정되며, 이에 따라 다른 천해역에서는 계절종의 유어가 대량 출현하려 높은 생물량을 보이는 난수기에 어류밀도가 낮은 것으로 판단된다.

• Journal of Ecology and Environment
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• 제34권3호
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• pp.295-305
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• 2011

Many studies have suggested the positive effects of grazing by large herbivorous mammals on seed dispersal, but little is known about how herbivores could affect the fate of ingested seeds. This study examined the effects of seed ingestion by sika deer (Cervus nippon) on seed fate in a temperate grassland established in an urban park long resided by high densities of sika deer. I compared species composition and seasonal traits of seed abundance and maturity in the grassland community with those in deer fecal pellets. In total, 27 herbaceous species were observed, including the predominant Zoysia japonica. Seed phenology and production differed among the three dominant species (Z. japonica, Digitaria violascens, and Hydrocotyle maritima). Pellets contained at least 26 species of herbaceous seeds, and their abundance differed among species. Of the 26 species, 15 were observed in the vegetation at the study site. The peak of seed abundance in pellets for the dominant species appeared 1 month after the peak of inflorescence production (but most of the inflorescences were immature and susceptible to digestion) and consequently corresponded to the peak of mature inflorescence. Because sika deer are likely to ingest seeds at any maturity stage in the grassland and immature seeds are less hardened, ingested immature seeds can suffer great losses. The results suggested that the survival of germable seeds with great losses of immature seeds may be a factor determining which plant species can be successfully dispersed by herbivores.

• 한국수산과학회지
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• 제43권5호
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• pp.503-509
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• 2010

The seasonal and interannual variation in the species composition and abundance of the decapod assemblage (shrimps, crabs, and hermit crabs) collected using pots in the coastal waters off Gori were studied between 2005 and 2008. During the study period, 49 decapod species belonging to 19 families were collected. The dominant species were Crangon hakodatei, Pandalus gracilis, Carcinoplax longimana, Charybdis bimaculata, Carcinoplax vestita, Diogenes edwardsii, and Dardanus arrosor. These seven species accounted for 95.46% of the total number of individuals collected. The number of species, number of individuals, biomass, and species diversity indices fluctuated with the seasons. The peak number and biomass of individuals occurred in July 2006. The number and biomass of individuals were higher in summer and lower in winter, and the diversity indices were lower in summer than in the other seasons. The abundance of dominant species showed some seasonal and interannual change; in particular, those of C. hakodatei and P. gracilis corresponded with the bottom water temperature.

• Journal of Forest and Environmental Science
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• 제37권3호
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• pp.217-225
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• 2021

This study evaluated the species composition, diversity and phorophyte preference of epiphytes at the University of Port Harcourt located in southern part of Nigeria. Purposive sampling technique was used to select sites representing major avenues in the three campuses (Abuja, Choba and Delta) of the University. Data were collected on species name of phorophytes, number of individuals, diameter at breast height (dbh) and height, and species/number of epiphytes present on them. The points/sections of attachment of epiphytes on phorophytes were also recorded. A total of eight species of epiphyte belonging to six families were recorded in the study. Species diversity was higher in Abuja campus (Simpson 1-D=0.81; Shannon H=1.79), followed by Choba campus (Simpson 1-D=0.73; Shannon H=1.09) and Delta campus (Simpson 1-D=0.56; Shannon H=0.93). Species richness was highest in Abuja campus (n=8) followed by Delta campus (n=4) and Choba campus (n=3). Similarity in epiphyte species composition was highest between Choba and Delta campuses (85.71%), followed by Delta and Abuja campuses (66.67%) and lowest between Choba and Abuja campuses (54.55%). The family-Polypodiaceae, had the highest number of species (n=3). Microgramma owariensis had the highest relative abundance (27%) followed by Platycerium bifurcatum (26%) while Tillandsia utriculata and Peperomia pellucida had the least relative abundance (3%). Epiphyte abundance was weakly correlated with both the dbh and height of phorophytes. However, epiphytes were more abundant on phorophytes with rough/scaly/corky/flaky barks than on those with smooth barks. The planting of avenue tree species with rough barks is recommended to enhance the diversity of epiphytes in the study area.

• 생태와환경
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• 제56권1호
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• pp.83-93
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• 2023

This study compares the abundance and community structure of zooplankton organisms from pelagic regions, and considers particularly the trophic levels vs. zooplankton abundances and biomass. Zooplankton samples were collected three times from May to November 2022, at 30 temperate lakes and reservoirs, which belong to four different river basins. The total zooplankton abundance, biomass and species index were showed considerable spatial variation. The spatial pattern of rotifer abundance was similar to that of total zooplankton abundance, while there were not showed similar patterns of zooplankton biomass (㎍ L^-1) in lentic ecosystems. The rotifer strongly dominated the zooplankton assemblage in smaller lentic system than that of larger. A total of 130 species of zooplankton were identified (83 rotifers, 34 cladocerans and 13 copepods). The total average of zooplankton abundance and biomass were 213.7±342.3 Ind. L^-1 (n=129) and 1382.8±1850.4 ㎍ L^-1, respectively. Total and average of zooplankton abundance were usually dominated by the rotifers (>56.9%), while those of zooplankton biomass were dominated by the cladocerans and copepods (>73.6%) in lentic ecosystems. Considering the Trophic State Index (TSI), the factors of zooplankton abundance and biomass were included in between meso- and eutrophic states(27 lakes, 90% of all). The mean abundance and biomass of zooplankton in eutrophic systems were higher than that of meso- and hypertrophic systems. From this result, we suggest that management strategy for the lentic ecosystem water environment has to be focused more on small-sized lakes and reservoirs, in terms of zooplankton assemblages.

• 한국해양학회지:바다
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• 제8권1호
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• pp.14-28
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• 2003

2001년 6월 광양만의 38개 조사정점에서 출현한 대형저서동물은 총 154종이었고, 평균 서식밀도는 1,286 개체/$m^2$였다. 다모류가 출현종수와 개체수에서 가장 우점한 동물분류군이었고, 주요 우점종은 다모류의 Tharyx sp.(44.8%), Lumbrineris longifolia(14.0%), 이매패류의 Mytilus edulis(6.5%), 단각류의 Corophium sinense(4.5%), 다모류의 Heteromastus filiformis(3.6%), Sigambra tentaculata(1.7%)등이었다. 광양만의 묘도 서쪽에 위치한 정점들에서 종 수와 개체수가 적었고, 광양만의 주수로역에서 풍부한 생물상을 보였다. 군집분석결과 7개 정점군으로 구분될 수 있었으며, 광양만의 서부해역은 환경교란에 의해 종조성에 차이를 보이는 다양한 저서생물군집으로 구성되어 있었다.

• ALGAE
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• 제37권4호
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• pp.281-291
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• 2022

Quantifying the abundance of Chattonella species is necessary to effectively manage the threats from ichthyotoxic raphidophytes, which can cause large-scale mortality of aquacultured fish in temperate waters. The identification and cell counting of Chattonella species have been conducted primarily on living cells without fixation by light microscopy because routine fixatives do not retain their morphological features. Species belonging to the Chattonella marina complex, including C. marina and C. marina var. ovata, had high genetic similarities and the lack of clear morphological delimitations between the species. To estimate the abundance of C. marina complex in marine plankton samples, we developed a protocol based on the droplet digital polymerase chain reaction (ddPCR) assay, with C. marina complex-specific primers targeting the internal transcribed spacer (ITS) region of the rDNA. Cell abundance of the C. marina complex can be determined using the ITS copy number per cell, ranging from 25 ± 1 for C. marina to 112 ± 7 for C. marina var. ovata. There were no significant differences in ITS copies estimated by the ddPCR assay between environmental DNA samples from various localities spiked with the same number of cells of culture strains. This approach can be employed to improve the monitoring efficiency of various marine protists and to support the implementation of management for harmful algal blooms, which are difficult to analyze using microscopy alone.

• 한국어류학회지
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• 제17권1호
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• pp.8-18
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• 2005

진동만 명주리 잘피밭에 서식하는 어류의 종조성 및 계절변동을 조사하기 위해서 2001년 8월 부터 2003년 7월까지 소형 비임트롤을 이용하여 어류를 매월 채집하였다. 조사기간 동안 어류는 총 33종이 채집되었다. 쥐노래미, 흰베도라치, 실양태, 가시망둑, 베도라치, 그물코쥐치, 실고기, 그리고 조피볼락이 많이 채집되었는데, 이들은 채집된 총 개체수의 79.5%를 차지하였다. 본 조사해역에서 채집된 어류는 대부분이 평균 15 cm 이하의 소형 어종이거나 대형 어종의 유어들로 구성되어 있었다. 잘피밭 어류군집은 뚜렷한 계절변동을 보였는데, 채집 개체수는 2002년 4월에서 6월 사이에 아주 높았으나, 생체량은 2001년과 2002년 9월에 각각 가장 높은 수치를 나타내었다. 대체적으로 겨울철에서는 채집 개체수 및 생체량이 모두 낮았다. 어류 군집의 계절변동은 잘피의현존량 및 먹이생물의 양적변동과 관계가 있었다.

• 한국수산과학회지
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• 제41권5호
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• pp.363-370
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• 2008

The ichthyofauna of certain reservoirs in Pohang-si, Gyeongsangbuk-do, were studied during the period from October 7-19, 2005. During the study period, 9,480 individuals (ind.) belonging to 22 species, 17 genera, 8 families and 4 orders were collected. Of these, 11 species were cyprinidae fishes, and the dominant species was Pseudorasbora parva (relative abundance 47.14%). There were six Korean endemic species (289 ind., relative abundance 3.04%), including Squalidus chankaensis tsuchigae, Squalidus mulimaculatus, Hemiculter eigenmanni, Iksookimia yongdokensis and Coreoperca herzi, and the dominant Korean endemic species was Pseudobagrus brevicorpus (relative abundance 3.04%) collected in Hoehakji, Cheonggyeji, Ahnsimji and Mabukji. There were five introduced species. Three species, including Hemiculter eigenmanni, Pseudobagrus fulvidraco and Hypomesus nipponensis, were introduced from other native stream systems, and two species, including Carassius cuvieri and Lepomis macrochirus, originated in foreign countries. Of these, Lepomis macrochirus (l,521 ind., relative abundance 16.05%) was collected at the all reservoirs except at Gidongji. These results suggest that the exotic fishes in question have been widely dispersed within the reservoirs in Pohang-si.