• Fisheries and Aquatic Sciences
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• v.11 no.3
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• pp.159-165
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• 2008

Intertidal benthic algal communities on the shores of Gujido and Daeyeonpyeongdo islets, Korea, were examined in October 2007. At both sites, 45 seaweeds including 7 green, 6 brown and 32 red algae were identified. The number of species at Gujido(38 species) was 1.5 times higher than at Daeyeonpyeongdo(25 species), but seaweed coverage was very similar with about 20%. Dominant seaweeds in terms of coverage and importance value were Hildenbrandtia sp., Caulacanthus okamurae, Ulva pertusa, and Gelidium amansii at Gujido and U. pertusa, Hildenbrandtia sp., Gelidium divaricatum at Daeyeonpyeongdo. The vertical distribution pattern of the seaweeds was G. divaricatum-U. pertusa, Hildenbrandtia sp.-U. pertusa, Hildenbrandtia sp., Ishige okamurae from upper to lower intertidal zone but seaweed zonations were not observed on the Gujido rocky shore. At both sites, coarsely-branched forms were the dominant functional group in species number and percent cover(among benthic algal species). The rocky shores of the two sites were dominated by crustose coralline and green algae, whose presence generally results in decreased seaweed biodiversity and community stability. Therefore, the shores of the Yeonpyeongdo islets are of considerable environmental concern and should be monitored for seaweed species composition and community structure.

• The Korean Journal of Malacology
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• v.17 no.1
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• pp.63-70
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• 2001

The distribution and seasonal changes of the intertidal macrobenthos community was performed on five intertidal rocky stations of Hwasoon at Jeju Islands September 1999 to August 2000. The macrobenthos was composed of six phyla, 13 classes, 24 orders, 49 families, and 97 species. The dominant species of the upper zones were Nodilittorina exigua, Notoacmea schrenckii, Liolophura japonica and Patelloida saccharina. Those of the middle zones were Monodonta labio, Chthamalus challengeri, Siphonalia japonica and Liolophura japonica. Those of the lower zones were Siphonalia sirius, Patelloida saccharina, Chthamalus challengeri, and Liolophura japonica. The community dominance indices of the upper zones were much higher than those of the middle and lower zones. Species diversity and evenness in all investigated zones were highest in station 1 and lowest in staton 3. But, species richness was highest in station 1 and lowest in station 4.

• ALGAE
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• v.32 no.4
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• pp.325-336
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• 2017

Intertidal community recovery and resilience were investigated with quantitative and qualitative perspectives as a function of disturbance timing. The study was conducted in a lower intertidal rock bed of the southern coast of South Korea. Six replicates of artificial disturbance of a $50cm{\times}50cm$ area were made by clearing all visible organisms on the rocky substrate in four seasons. Each of the seasonally cleared plots was monitored until the percent cover data reached the control plot level. There was a significant difference among disturbance timing during the recovery process in terms of speed and community components. After disturbances occurred, Ulva pertusa selectively preoccupied empty spaces quickly (in 2-4 months) and strongly (50-90%) in all plots except for the summer plots where non-Ulva species dominated throughout the recovery period. U. pertusa acted as a very important biological variable that determined the quantitative and qualitative recovery capability of a community. The qualitative recovery of communities was rapid in summer plots where U. pertusa did not recruit and the community recovery rate was the lowest in winter plots where U. pertusa was highly recruited with a long duration of distribution. In this study, U. pertusa was a pioneer species while being a dominant species and acted as a clearly negative element in the process of qualitative recovery after disturbance. However, the negative effect of U. pertusa did not occur in summer plots, indicating that disturbance timing should be considered as a parameter in understanding intertidal community resilience in temperate regions with four distinct seasons.

• The Korean Journal of Ecology
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• v.14 no.1
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• pp.63-73
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• 1991

Nakdong estuary provides the largest wintering grounds for migrating waterfowls in Korea, and was designated Natural Monument No. 179 in 1966. Nakdong barrage and related construction-projects finished in 1987 to increase freshwater-supply to nearby Pusan metropolitan area and to reclaim the vast intertidal areas for land development. Changes on distribution, primary productivity, and standing crop of Schoenopluctus triqueter, the dominant species in this intertidal flats, were investigated after the construciton, during the 1988-1990, and were compared to those before the construction. Total standing crop. tuber biomass and net primary productivity of S. triqueter increased in 1988 and 1989, but decreased slightly in 1990. Increase of tuber biomass means an increase in available food, thus the carrying capacity, for swans wintering in this area. Habitat environment of this estuary should be protected and managed as a wintering ground for migrating waterfowls, inspite of the construction of the barrage.

• Ocean and Polar Research
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• v.42 no.1
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• pp.21-31
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• 2020

Shorebirds migrating along the East Asian-Australasian Flyway (EAAF) have been drastically decreasing due to continuous area loss and quality degradation of intertidal mudflats in the Yellow Sea. Evaluating the current habitat quality by means of habitat carrying capacity estimation could be effective in predicting the magnitude of impacts caused by habitat loss and provide better understanding to improve management strategies. In this study, we estimated the total biomass of Macrophthalmus japonicus, a main prey item of curlews in the Korea peninsular as habitat carrying capacity of the southern intertidal mudflat of Ganghwa Island, one of the key stopover sites for curlews in the EAAF. The result of the estimation took into account spatial differences of prey biomass and the available foraging time by tide patterns. Accordingly, it was found that curlew populations account for 30.26% of the habitat carrying capacity. When we calculated the mean biomass of the area and extrapolated it to the whole area to calculate the total biomass, it was found that the curlews have consumed 10.92% of the total biomass. The results show that the habitat carrying capacity of the southern intertidal mudflat of Ganghwa Island has decreased by 7.8% compared to a study conducted twenty years ago employing the same method. This study shows that there can be considerable differences in the results of habitat carrying capacity estimation between different methods, indicating that various environmental factors that affect the estimation results of habitat carrying capacity must be considered to achieve a more precise analysis and assessment.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.1
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• pp.300-307
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• 2015

Seasonal variation in marine macroalgal community structure was examined at the intertidal zones of Geumgap, Jindo, Korea, from October 2013 to August 2014. In total, 56 macroalgal species were identified, including 9 green, 12 brown, and 35 red algae. Annual seaweed biomass was 548.96 g wet wt. /$m^2$ with seasonal range between 371.08 g wet wt. /$m^2$ at summer and 32.91 g wet wt. /$m^2$ at winter. The dominant seaweed in terms of biomass was Sargassum thunbergii and subdominant species were Gelidium elegans, Sargassum fusiforme, and Ishige okamurae. The vertical distribution of seaweeds from the upper to lower intertidal zones was Gloiopeltis spp., Ulva spp.- S. thunbergii, S. fusiforme, Ishige okamurae - S. thunbergii, S. fusiforme, G. elegans. Annual seaweed coverage, richness index (R), evenness index (J'), and diversity index (H') values were 27.95%, 6.10, 0.38, and 1.38, respectively. Coarsely branched form was the most dominant functional group in terms of species number and biomass among benthic macroalgal species.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.4
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• pp.331-337
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• 2017

This study was carried out to analyze the community structure and distribution of macrobenthos at the intertidal zone of Jukbyeon in Uljin-gun during 2015-2016. The number of species were total 41 from 5 phyla. The species composition of Cnidaria 4, Mollusca 19, Annelida 3, Arthropoda 13, Echinodermata 2 and the individuals was $1,642inds./m^2$ and the weight was $1,959.42gWWt./m^2$ in the study area. The dominant species of the upper zones were Chthamalus challengeri and Nodilittorina radiata. Those of the lower zones were Mytilus galloprovincialis, Nipponacmaea schrenckii and Chlorostoma turbinata. The dominant species of the upper zones of winter and spring were C. challengeri, the summer and autumn of the N. radiata. Those of the lower zones were all seasonal of M. galloprovincialis. As a result of cluster analysis, those regions were divided in three groups, which were a group A of December 2015, August 2015 and February to August 2016 of intertidal zone lower, group B of December 2016 and May 2015 of intertidal zone lower, group C of intertidal zone upper.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.4
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• pp.295-306
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• 2004

Spatial patterns in the macrobenthic community structure in the inter- and subtidal zones in front of the Iwon Dike and environmental variables were examined in August 2001, In total, 156 macrobenthic species(123 intertidal species and 90 subtidal species) were recorded during this study, predominately polychaetes $(40{\%})$, bivalves $(22{\%})$, and crustaceans $(22{\%})$. Polychaetes made up less than $40{\%}$ of the intertidal communitr, but more than $50{\%}$ of the subtidal community. The mean density during this study was $1,456ind./m^{2}.$ Multivariate analysis (multidimensional scaling) revealed significant differences in community structure among four regions: near the Iwon dike (B1), the high and middle intertidal zone (B2), low intertidal zone (Al), and subtidal zone (A2). The number of species, total density, and diversity (H') varied significantly among the four regions. The distribution of macrobenthic community was affected by environmental variables, such as ${\%}$ silt/clay content, total sulfide, lose of ignition, and chemical oxygen demand. These environmental variables were negatively correlated with the dominant species (Nephtys polybranchia, Umbonium thomasi, and Scoloplos armiger) in the intertidal area, but positively correlated with the dominant species (Lumbrineris cruzensis, Notomastus latericeus, and Moerella sp.) in the subtidal area. Environmental variables $({\%}\;silt/clay content and total sulfide)$ were positively correlated with the dominant species (Heteromastus filiformis) in region Bl, but negatively correlated with the dominant species (Umbonium thomasi and Scoloplos koreanus) in region B2. Amphipods Urothoe spp. and Monoculodes koreanus were the dominant species in region Al. Umbonium thomasi, the dominant species in region B2, was not found in regions Bl or Al. We suggest that the inter-specific competition for territory and exposure to seawater may be important factors controlling the macrobenthic community structure in the inter- and subtidal zones in front of the Iwon Dike.

• Journal of Plant Biology
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• v.33 no.4
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• pp.225-236
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• 1990

Intertidal algal communities of Muchangpo and Maryangri in western coast of Korea were investigated qualitatively and quantitatively. Seasonal assessments of species composition, biomass, dominant species in biomass and vertical distributional pattern were conducted from July 1986 to April 1988. Ninety-nine species of marine algae (13 Cyanophyta, 12 Chlorophyta, 24 Phaeophyta and 50 Rhodophyta) were observed, of which 90 (13 Cyanophyta, 11 Chlorophyta, 23 Phaeophyta and 43 Rhodophyta) were from Muchangpo and 83 (10 Cyanophyta, 11 Chlorophyta, 21 Phaeophyta and 41 Rhodophyta) were from Maryangri, respectively. Ordination by detrended correspondence analysis based on the floristic data from nine localities indicated that, on the whole, marine algal distribution in western coast of Korea might be divided into two regions, i.e. the north and the south, being separated at the Taean Peninsula, the mid-western coast. Seasonal fluctuations of mean biomass were 44.55-201.19g-dry wt/$m^2$ at Muchangpo and 19.59-134.76g-dry wt/$m^2$ at Maryangri. Important species determined by the specific proportion of biomass were Sargassum thunbergii, Pelvetia siliquosa and Corallina pilulifera at Muchangpo, and Sargassum thunbergii and Corallina pilulifera at Maryangri.

• Korean Journal of Environment and Ecology
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• v.29 no.2
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• pp.221-227
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• 2015

This study was carried out to measure seasonal changes in the community structure and species composition of marobenthos in the intertidal area of Dokdo. The macrobenthos identified during this study was comprised of 36 species: predominately 25 species of mollusks(69.4 %), 6 species of arthropods(16.7 %), 3 species of echinodermata(8.3 %) and 1 species of cnidaria (5.6 %). The number of marobenthos species ranged from 27 in Spring to 33 in Autumn. In terms of the top 10 dominant species, there were 7 species of mollusks and 3 species of arthropods in the this study. After analyzing the bray-curtis similarity, it was divided into two large groups(A, B). Such group classification matched the SIMPROF(Similarity Profile Analysis) and the one-way ANOSIM(Analysis of similarities) analysis.