• Ocean and Polar Research
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• v.26 no.2
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• pp.311-321
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• 2004

Relationships between sedimentary environments and abundance of benthic animals were examined on the deep-sea floor, the Clarion-Clipperton Fracture Zone, in the northeast equatorial Pacific Ocean. Specimens were collected using a box corer at 8 stations by sieving through 0.3 mm mesh screen. Sediments showed finer grain size ranged from 5.63 to $7.97{\varphi}$, 83.1% of mean porosity, 1.81 kPa of mean shear strength and organic carbon content in sediment ranged from 0.97 to $1.87\;mg/cm^3$. Manganese nodules covered on the bottom layer from 4 to 57% of coverages. A total of 26 faunal groups in 6 phyla was sampled and comprised 1,467 individuals. Mean biomass were calibrated to 0.5 gWWt/$0.06\;m^2$. Small-sized animals including foraminiferans and nematods were dominated among the faunal group which comprised 49.1% (892 ind.) and 11.5% (320 ind.), respectively. In SPI-analysis, vertical bio-disturbance marks were not observed except to Beggiatoa-type bacterial mats. As the results of relationship between environments and benthos, abundance of benthic animals, especially nematode, showed only a negative correlation to the coverage of nodules, and any other sedimentary factors analyzed in this study were rarely affected to the spatial distribution of benthic animals.

• 한국해양학회지
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• v.28 no.4
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• pp.305-312
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• 1993

This study was carried out to investigate the benthic polychaetous community in the coastal area near Samchunpo City, in September and October of 1989. Polychaete, the dominant faunal group occupying 61.7% in the total faunal density, comprised a total of 50 species with a mean density of 112 indiv.m/SUP -2/. The Number of species and density were higher on the coastal area near Samchunpo Harbor and Samyang Sang-do. The most dominant Polychaete was Terebellides horikoshii (17.1%), followed by Lumbrineris longifolia (14.7%), and Mediomastus sp. (11.5%). The cluster analysis revealed that the study area could be divided into two areas. Each area sustained its specific benthic Polychaete assemblage; Terebellides-Heterogamous assemblage was located in the inner area from Samyang-do, and Lumbrineris-Mediomastus assemblage in the outer area. Lumbrineris-Heterogamous assemblage had higher polychaetous density and species number. Heterogamous sp. was the characteristic species occurring only in Terebellides-Heteromastus assemblage, whereas Mediomastus sp. only in Lumbrineris-Mediomastus assemblage.

• 한국해양학회지
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• v.30 no.4
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• pp.250-261
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• 1995

This study was carried out to investigate the distribution of the benthic polychaetous community in Kamak Bay, in summer of 1993. Polychaetes, the dominant faunal group comprising 74.5% of the total number of fauna, consisted of a total of 84 species with a mean density of 112 indiv.m/SUP -2/. The number of species and density were higher in the mouth area of the bay than in the rest of the bay. The most dominant Polychaete was Tharyx sp.(31.9%), followed by Lumbrineris longifolia (27.5%), Chone sp.(4.5%) and Glycera chirori (4.2%). The correspondence analysis revealed that the study area could be divided into four regions. Northeastern channel and southern mouth region of the bay, named Tharyx-Chone assemblage, sustained higher polychaetous density and species number due to the active water exchange with the outer off-sea, whereas northwestern region of the bay had the poorest polychaetous assemblage in the species number and faunal density owing to the blocking water exchange, high organic enrichment in sediment, and low dissolved oxygen content of bottom water. The central region, named Praxillella-Terebellides assemblage and Gly-cera assemblage, was the transition zone between another two region in species composition.

• Journal of Ecology and Environment
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• v.47 no.4
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• pp.250-260
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• 2023

Background: Crabgrass (Digitaria ciliaris, Poaceae) is a globally distributed weed, including in Afro-Eurasia, America, and Australia. As a highly gregarious plant, crabgrass is an important habitat for a diverse array of insects, and a potential habitat for agricultural pests. To compare the insect communities associated with the crabgrass community, insects were sampled using sweep sampling (100 sweeps per sample) at five sites, including Daejeon (Daejeon and Gap rivers), Anseong, Namhae, and Inje, with a focus on the Daejeon River. Results: A total of 5,888 individual insects belonging to eight orders, 42 families, and 115 species were collected from the five sites. Both the number of species and individuals of Hemiptera were the highest at all of the sites. In the present study, 73% of the insect population fed on D. ciliaris as a host plant. The dominant species in the D. ciliaris community was Laodelphax striatellus (Delphacidae), being ubiquitous at all the sites which showed a high abundance of rice pests in the communities and the suitability of D. ciliaris as an alternative host plant for them. The Shannon-Wiener diversity index was highest in Inje on 17 September (2.88), and the Chao1-bc diversity index was highest in the Gap River on 5 September (80). The sampling efficiency of 100 sweep samples (sample coverage) was calculated to be as high as 90%. The results of the samples taken from September to November in the Daejeon River showed that the number of species and individuals decreased gradually over time, and the number of dominant species decreased sharply between September and October. Similarity analysis indicated that sampling dates that were closer together yielded sampled assemblages with higher faunal similarity. In addition, in each sampling, the difference in the minimum temperature during the two-week period prior to sampling and faunal similarities were negatively correlated. Conclusions: This study provides foundational data that could enhance our understanding of insect diversity in D. ciliaris. The data can facilitate ecological conservation and management of Korean grasslands generally, as well as identification of potential pests that may disperse from D. ciliaris communities to nearby farmland.

• 한국해양학회지
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• v.22 no.3
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• pp.153-167
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• 1987

The most usually adopted methods from the collection of samples laboratory procedures, to basic analysis of assemblages for the quantitative study of benthic foraminifera are reviewed. Standard methods of treatment of sampleswith emphasis on the effective detection of contamination through routine dip of sieved into Methylene Blue solution after every washing of samples are proposed to minimize differences due to individuals and for comparisons of results in future. Some basic characteristics for the quantitative analyses are also reviewed with appropriate examples. These characteristics are related to toraminiferal abundance, wall structures, condition of test conservation, diversity and related characteristics, faunal similarith between samples, and occurrence of planktonic foraminifera.

• Ocean and Polar Research
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• v.24 no.4
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• pp.429-442
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• 2002

The faunal assembalges of macrobenthos and their habitat conditions on the soft-bottoms around Dokdo(Dok Island) was investigated using a box corer and a van Veen grab in Sept. 1999 and May 2000. The sediments in the slope sites were composed of sand particles and those in Ullneung Basin were mud. The sediments in the shelf sites were in the range of fine to medium sand. The organic content of the slope sediments was in the range of 1 to 2%. The macrobenthos occurred at the slope sites represented by 15faunal groups belonging to 8 phyla, and the major faunal group was polychaetous annelids. They comprised ca. 80.6% in slope sites, and 84.8% in shelf sites. Dominant species in the slope were Exogone verugera(40.9%), Cossura longocirrata (8.4%), Tharyx sp. (6.6%), Scalibregma inflatum (4.9%), Aedicira sp. (4.7%), Aricidea ramosa (3.8%), and Sigambra tentaculata (3.7%). Dominant species in the shelf were Chone sp. (49.3%), Tharyx sp. (18.4%), Ophelina acuminata (6.7%), Chaetozone setosa (3.8%), Glycera sp. (2.6%), and Aedicira sp. (2.4%). The mean densities of macrobenthos in the slope and shelf area were $2,028\;ind./m^2$ and $456\;ind./m^2$, respectively. The trophic composition of benthic polychaete worms in the slope area was different from that in shallow shelf area: surface deposit feeding worms were most abundant in slope area whereas filter feeding worms in shelf area. According to the cluster analysis and MDS plots, the spatial distribution of macrobenthos in Dokdo slope region was related with the sediment properties such as particle size and organic content. In the case of vertical distribution of macrobenthos in slope sites, most faunas concentrated in the upper sediment layer within 2cm depth.

• The Korean Journal of Malacology
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• v.25 no.1
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• pp.71-79
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• 2009

Based on investigation of archive collections of A.V. Zhirmunsky Institute of Marine Biology of the Far-Eastern Branch of the Russian Academy of Sciences (Vladivostok) and O.A. Scarlato Zoological Institute of the Russian Academy of Sciences (Saint Petersburg), as well as on the analysis of published data, the species composition of shell-bearing gastropod mollusks of the Russian waters of the East Sea (Sea of Japan), consisting of 331 species and subspecies, has been identified. The fourth part of the Review includes 46 species of Heterobranchia (Allogastropoda, Opistobranchia, and Pulmonata). Each species is assigned to a biogeographic grouping in the study area. Its type locality and habitat (depth and substrate) are also documented.

• The Korean Journal of Malacology
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• v.25 no.1
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• pp.51-70
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• 2009

Based on investigation of collections at the A.V. Zhirmunsky Institute of Marine Biology of the Far-Eastern Branch of the Russian Academy of Sciences (Vladivostok) and Zoological Institute of the Russian Academy of Sciences (Saint Petersburg), as well as on the analysis of published data, the species composition of shell-bearing gastropod mollusks of the Russian waters of the East Sea (Sea of Japan), consisting of 331 species and subspecies, has been identified. Each species is assigned to a biogeographic grouping in the study area. Its type locality and habitat (depth and substrate) are also documented. The third part of this review includes 129 species in Neogastropoda (Caenogastropoda).

• Journal of the korean society of oceanography
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• v.31 no.1
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• pp.7-17
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• 1996

The species composition and distribution patterns of the subtidal benthic faunal assemblage in Sokmo and Yomha Channels and Kyonggi Bay were studied in spring and fall of 1989 and correlated to some environmental variables: temperature, salinity and substrate type. For both seasons, a total of 7,779 organisms were counted belonging to 244 species. Of these, 3,647 organisms in 185 species were counted for spring (March 1989) and 4,132 in 189 species for fall (September 1989). The oyster, Cressostrea gigas and the tellinidean bivalve, Moerella rutilla were the two most abundant species in the spring, constituting 17.22%and 6.47% of the total abundance respectively. While in the fall, the barnacle, Balanus reticulatus and macrura, Ogyrides orientalis dominated comprising 13.72% and 6.87 % of the total number of individuals. Community structure analysis revealed good correlations with the variations of salinity in Yomha and Sokmo Channels and sedimentary facies in Kyonggi Bay, Korea.

• The Korean Journal of Malacology
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• v.26 no.2
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• pp.127-143
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• 2010

Based on investigation of collections at the A.V.Zhirmunsky Institute of Marine Biology of the Far-Eastern Branch of the Russian Academy of Sciences (Vladivostok) and Zoological Institute of the Russian Academy of Sciences (Saint-Petersburg), as well as on the analysis of published data, the species composition of shell-bearing gastropod mollusks of the Russian waters of the East Sea, consisting of 331 species and subspecies, has been identified. Eachspecies is assigned to a biogeographic grouping in the study area. Its type locality and habitat (depth and substrate) are also documented. The second part of this review includes 101 species from Sorbeoconcha and Hypsogastropoda (Caenogastropoda).