• ALGAE
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• v.20 no.4
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• pp.369-377
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• 2005

Seashore joining with land and sea, which is typical habitat for marine macroalgae, is classified two types of shore as soft- and hard-bottom shore according to topographical (geological) and ecological features. We compared two of Ulva pertusa Kjellman from two contrasting habitats, sandy (soft-bottom, Haenam) and rocky shore (hard-bottom, Hadong) in terms of chlorophyll-a fluorescence and its parameters, and various photosynthetic pigment and nutrient content in the tissue of those. Both of habitats were different in the light environment such as light attenuation coefficient and even in nutrient concentration of ambient seawater. Electron transport rate (ETR) of Ulva from sandy shore was higher than from rocky shore. The range of photosynthetic pigment content in the tissue of U. pertusa was significantly much more in from sandy shore, and also nitrogen and phosphorus content were significantly higher except for carbon content. However, there were no significant differences in the ratio of among photosynthetic pigments, and N:P ratio was similar between each other, even though significantly different. Our result implied on the reason of why most of green tides in the worldwide concentrated and frequently occurred at sites with sandy, muddy and silty bottoms, being classified as soft-bottom shore.

• Korean Journal of Ichthyology
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• v.30 no.1
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• pp.55-64
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• 2018

Fish assemblages in a sandy shore and an eelgrass bed were compared based on monthly samples in the southern coastal water of Korea. Samples were collected by a beam trawl in the sandy shore and a surf net in the eelgrass from March to February 2012. The common fish species were Syngnathus schlegeli, Pseudoblennius cottoides, Pholis nebulosa, Favonigobius gymnauchen, Gymnogobius heptacanthus, Pseudopleuronectes yokohamae, Takifugu niphobles. Among them S. schlegeli, Urocampus nanus, P. cottoides, P. nebulosa, T. niphobles were high abundance in the eelgrass bed than in the sandy shore, whereas Acanthogobius flavimanus, Acentrogobius pflaumi, F. gymnauchen, G. heptacanthus, P. yokohamae were high in the sandy shore. Aulichthys japonicus, Hippocampus coronatus, Sebastes inermis, Lateolabrax japonicus, Siganus fuscescens were found in the eelgrass bed, and Thryssa hamiltoni, Mugil cephalus, Inimicus japonicus, Platycephalus indicus, Hexagrammos otakii, Furcina ishikawae, Liparis tanakae, Repomucenus curvicornis, and Eutaeniichthys gilli were observed in the sandy shore. Species composition and abundance varied seasonally in two habitats; The number of species and abundance was high in August and September, while biomass was the highest in April and September. Fish numbers as well as biomass were lowest in February. Number of individuals and biomass of fish in the eelgrass bed were significantly higher than those of in the sandy shore. Some fish preferred to live in the eelgrass were collected in the sandy shore, while fish preferred to live in the sandy shore were rarely collected in the eelgrass.

• Ocean Science Journal
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• v.43 no.3
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• pp.127-133
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• 2008

Reproductive patterns of an epifaunal amphipod, Pontogeneia rostrata, were studied on Dolsando sandy shore in Korea. The life history pattern was iteroparous, with recruitment mainly occurring from winter to spring. The sex ratio was malebiased, especially during breeding periods. The mean body length of females was significantly larger than that of males. Brood size and egg volume were positively related to the body length of ovigerous females. There was no significant difference in brood size between successive breeding periods, but egg volumes were significantly higher in early winter (December) than in late spring breeding (May and June), increasing the probability of survival to hatching. These traits contribute to more reproductive potential in early winter than in late spring breeding. The mean brood size of epifaunal P. rostrata was larger but the mean egg volume smaller than that of infaunal amphipods in this sampling area. We suggest that reproductive effort for epifaunal species may be proportionally greater than for infaunal species in risky environments.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.457-458
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• 2001

Reproductive and life history patterns of marine amphipods are influenced by a variety of biotic and abiotic factors. Those factors may vary on local scales or along geographic patterns and result local or geographic variations in reproduction and life history. Although many studies in life history of amphipods were carried out at various habitats, limited information on the life history and reproduction at a shallow sandy shore 〈 1 m depth is available (Bear and Moore, 1996). (omitted)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.479-480
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• 2001

Harpacticoid copepods are one of the most important components in the benthic meiofaunal community. In spite of their numerical significance the study of harpacticoids in Korea, as distinct from meiofauna in general (Kim et al., 1998, 2000a, b), has been limited. During the course of investigation on ecological significance of harpacticoids in the intertidal sandy shore, a new species of the genus Rhizothrix was determined and described here. (omitted)

• Ocean and Polar Research
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• v.35 no.1
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• pp.27-37
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• 2013

The western coast of Anmyeondo is open toward the Yellow sea and the northern and southern coasts are sandy and have simple coastlines. In this study, we investigated the spatial distribution and community structure of the macrobenthos that inhabit the sandy shore of Anmyeondo. For the study, we chose 8 sites encompassing 44 stations. In total, we have recorded 62 species, and collected 747 inds./$m^2$ on average. Zonation pattern did not appear because the mean grain size and organic contents of the study sites were similar among the macrobenthos. Polychaetes were most frequently recorded, but amphipods appeared in higher mean density. Macrobenthic community is classified into 3 groups largely based on the density difference among the dominant species and the groups were not influenced by environmental factors. The aggregated distribution of macrobenthos did not show a clear regional spatial difference but exhibited classification pattern emphasizing the density difference of the dominant species. The sandy shores of Anmyeondo are relatively more influenced by waves compared to other regions and the sediment moves more due to strong winds, etc. at low tide. We presume that the movement of sediment resulted in a relatively even sedimentary environment and consequently weakened environmental variables that change with the tide level. We concluded that the macrobenthic community does not show the zonation pattern in the sandy shores of Anmyeondo due to such influences.

• Journal of The Geomorphological Association of Korea
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• v.25 no.4
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• pp.21-35
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• 2018

The distribution and size of sandy beaches along eastern Korea has a close relationship with the presence of granite rocks. In general, elongated and wide beaches with abundant sands are likely to develop along the coasts where granitic basic rocks comprise the dominant geology or where a large amount of sands are supplied by streams from inland granitic rocks. Small sandy beaches, in contrast, appear in non-granitic rocks (i.e., under sedimentary and/or metamorphic geology). Hence, large beaches are observed continuously along the shore of Gangwon-do, of which coasts consist predominantly of granitic geology. Such continuity declines from Samcheok city to Pohang city. The rock of Gyeonbuk-do is commonly known as sedimentary, deposited between the late Triassic and the early Tertiary Periods. Because few sands are supplied from the upstream areas, sandy beaches unlikely develop along the coasts of the province, only showing a sporadic, discontinuous distribution under Bulguksa granite, granitic gneiss, and some volcanic rocks. Erosion was rarely observed in the beaches where granitic rocks are distributed, whereas merely five beaches seemed to have undergone some level of erosion in non-granitic regions. This is presumably because a larger amount of sands than that which had been eroded away was replenished in areas under granitic geology, while under non-granitic geology having a deficit in sands, no large sandy beaches had formed at first.

• Korean Journal of Ichthyology
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• v.24 no.1
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• pp.11-19
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• 2012

Seasonal fish species composition in the sandy shore adjacent to eelgrass bed was determined. Monthly samples were collected by a beam trawl from August 2009 to July 2010. A total of 38 species, 1,232 individuals and 5,277.7g of fishes were collected. The dominant species were $Favonigobius$ $gymnauchen$, $Takifugu$ $niphobles$, $Hypodytes$ $rubripinnis$, and $Rudarius$ $ercodes$. These four dominant fish accounted for 73.2% of the total number of individuals, and 53.9% of the biomass of collected fish. During the survey, the water temperature ranged from 11 to $25^{\circ}C$, and the salinity ranged from 29 to 35 psu. The monthly species diversity index showed the lowest value of 0.89 in March and highest value of 2.35 in June 2010. Fish species composition and abundance in Myeongsa sandy shore, were similar to that the adjacent eelgrass bed, but were different from those of Gujora sandy shore open the sea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.340-348
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• 1997

Sledge net samples were taken over the neap and spring tide cycles in January 1993 from the bottom and surface of 1 m depth and at the water's edge in the sandy shore surf zone of Dolsando, southern Korea. Zonation pattern of three dominant gammarid amphipods was compared. The amphipods were more abundant on the bottom and at water's edge than in the surface. Average densities at both sites of Pontogeneia rostrata and Allorchestes angusta were higher during the neap tide than the spring tide, whereas that of Synchelidium lenorostralum was lower during the neap tide. P. rostrata migrated horizontally during the flooding and ebbing tides, but S. lenorostralum and A. angusta did not. Unlike other species, P. rostrata was significantly more abundant at night, suggesting its active nocturnal movement. During flooding tide, P. rostrata was not found on the shore above the mean sea level (MSL) during daytime, but found in 100 cm above MSL at night. Zonal distribution of P. rostrata which was restricted from MSL to 250 cm below MSL, however, did not vary with the day-night cycle during ebbing tide. S. lenorostralum and A. angusta were not found during flooding tide but ebbing tide. The upper distribution limit of the former was 150 cm below MSL, and the distribution of the latter ranged from MSL to 150 cm below MSL. The highest densities of P. rostrata, S. lenorostralum and A. angusta were 32, 26 and 3 ind. $m^{-2}$, respectively. We discussed the relationships between the distribution pattern of three dominant species of gammarid amphipods and their life styles in the sandy shore.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.6
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• pp.594-599
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• 2001

In a sandy shore surf zone of Dolsan Island, diel, tidal and seasonal effects on abundance of Acartia omorii were investigated at three sites, the bottom and surface of 1 m depth and water's edge using a sledge-net. Of these sites, the abundance of A. omorii was the highest in the bottom. Seasonal abundance data showed that A. omorii was more abundant in winter than other seasons. During the study period, the abundance of A. omorii was always higher during ebb tide than flood, The distribution patterns of A. omorii were more influenced by tide than diel change, Strong current during spring tide possiblely affected the diel migration pattern, In winter A. omorii showed a diel vortical migration in neap tide, whereas it showed a reverse vortical diel migration in spring tide. Distribution centers were located at a layer of $50\~100\;cm$ below mean sea level (MSL) during neap tide, and then it moved slightly upward during spring tide.