• 한국수산과학회지
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• 제43권5호
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• pp.532-539
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• 2010

Seaweed biomass was estimated in the rocky subtidal zone of Daejin on the mid-east coast of Korea using a destructive sampling method from February to November 2007. Monthly sampling was conducted at depths of 5, 10 and 15 m using 50 $\times$ 50 cm quadrats. A total of 73 species, including 5 chlorophytes, 25 phaeophytes, 43 rhodophytes and one seagrass were identified. Average seaweed biomass was 2,852.3 g wet wt. $m^{-2}$ and biomass values varied monthly from 1,189.8 g to 7,523.7 g. The species dominant in biomass were Laminaria japonica (481.7 g), Sargassum confusum (470.85 g), Undaria pinnatifida (422.57 g), Costaria costata (282.16 g), Odonthalia corymbifera (174.46 g), S. sagamianum (163.22 g) and S. horneri (122.18 g). The vertical distribution of algae was characterized by S. confusum and U. pinnatifida at 5 m, L. japonica and U. pinnatifida at 10 m, and O. corymbifera and L. japonica at 15 m depth. The C/P, R/P and (R+C)/P values were 0.20, 1.72 and 1.92, respectively.

• ALGAE
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• 제23권4호
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• pp.327-334
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• 2008

Seaweed biomass was estimated using a nondestructive sampling method in the rocky intertidal and subtidal zone in Daejin on the mid-east coast of Korea from August 2006 to April 2008. Seasonal sampling were done at the depth of 0, 1, 5, 10 m using 50 x 50 cm quadrat. A total of 95 species, including 11 chlorophytes, 26 phaeophytes, 57 rhodophytes and one sea grass were identified. Mean biomass was comprised of 1,292 g wet wt m$^{-2}$ and the biomass values varied seasonally from 904 g to 1,945 g. Dominant species in biomass were Sargassum spp. (S. horneri, S. yezoense), Corallina pilulifera, Phyllospadix japonica, Symphyocladia latiuscula, Hizikia fusiformis, Codium arabicum and Chondrus ocellatus at Daejin. The vertical distribution of algae were characterized by Corallina pilulifera, Symphyocladia latiuscula, Sargassum spp. (S. confusum, S. yezoense), Hizikia fusiformis and Grateloupia elliptica at intertidal zone, Sargassum spp. (S. fulvellum, S. horneri, S. yezoense), Phyllospadix japonica, Codium arabicum, Undaria pinnatifida and Corallina pilulifera at 1 m depth, Sargassum spp. (S. horneri, S. micracanthum, S. yezoense), Phyllospadix japonica, Grateloupia elliptica, Gelidium amansii and Codium arabicum at 5 m depth and Phyllospadix japonica, Codium arabicum, Sargassum spp. (S. horneri, S. micracanthum, S. yezoense) and Undaria pinnatifida at 10 m depth.

• 한국제4기학회지
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• 제5권1호
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• pp.33-45
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• 1991

조류가 강한 만경강-동진강 부근의 연안역에는 많은 사주들이 잘 발달하여 있다. 그 중 한 사주에서 측정된 조류는 그 최대유속이 밀물과 절물 사이에 심한 비대칭 현상을 나타낸다. 사주의 남쪽 측면에서는 밀물이 우세하고 북쪽 측면에서는 썰물이 우세한 이러한 비대칭성은 대조시 유속이 강할 때 더욱 뚜렷이 나타난다. 또한 남쪽의 밀물 우세 현상은 북쪽의 썰물 우세 현상 보다 더욱 강하게 나타나고 있어 사주는 전체적으로 밀물에 의하여 더 큰 영향을 받고 있다. 모래로 이루어진 이 지역의 해저 퇴적물들은 대부분 조류에 의해 밑짐으로 이동되고 있으며, 이러한 조류의 비대칭성으로 인하여 모래는 어느 한 방향으로 순 이동이 일어나게 된다. 이러한 모래의 순 이동은 남쪽에서는 해안쪽으로 북쪽에서는 외해쪽으로 이동하여 바닥의 모래는 사주를 반시계 방향으로 순환하는 양상을 띄게 될 것이며 전체적으로는 강한 밀물의 영향으로 사주가 해안쪽으로 이동하는 결과를 가능하게 할 것이다. 사주의 남쪽부분의 형태가 불규칙적이고 V자 모양을 나타내는 것도 이러한 강한 밀물의 영향을 반영하는 것으로 해석된다.

• 자연과학논문집
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• 제4권
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• pp.11-22
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• 1991

Early studies on Korean Sargassum subjenus Bactrophycus were partly started by Kyetzubg(1843,1849), J. Agardh(1889), Cotton(1906), Yendo(1907) and Okamura(1913, 1914, 1915, 1917). Kang(1966) reported 15 species and 4 subspecies of Sargassum subgenus Bactrophycus and their wide distribution on the Korean coasts in his paper [On the geographical distribution of marine algae in Korea], a foundation stone of Korean phycology. In fact, all the Korean coasts and subtidal zone are inhabited by Sargassum plants. They constitute the most part of the primary production and dominant species of benthic algal vegetation. In 1974, L.K. Lee began to study Sargassum monographically as seaweed resources in Korea. The Koreans eat some species of Sargassum (including Hizikia fusiformis) or use them as fertilizer of the farm near the coast. Among the reported 17 species of Korean Fucales, 12 species belong to Bactrophycus. Yoo(1976) dealt with the descriptions, figures, and a key of 24 species of Korean Fucales plants in her M.S. thesis paper. Among them 16 species belonged to Bactrophycus. Even though the above two works were done with thorough observation of the dry specimens kept in the Pusan Fisheries University Herbarium (most of them were identified by Kang, J.W.) and nation-wide collections, great morphological varieties of these taxa made Lee and Yoo hesitate to publish the paper. Instead, the serial chemotaxonomic studies on the geographical variations of Korean Fucales plants(Yoo and Lee, 1988a, 1988b ; Yoo, et al., 1988) were held to solve the problem, while foreign papers (especially both Drs Tseng's and Yoshida's serial works on Bactrophycus). and authenthic specimens that foreign scholors sent to Korean phycologists induced them to find that several species of Sargassum had been misidentified from the beginning. We introduce here Korean Sargassum subgenus Bactrophycus according to Tseng et al. (1985), mentioning briefly the characteristics of the species, key, and distribution on the Korean coasts.

• Journal of Plant Biology
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• 제26권4호
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• pp.181-190
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• 1983

Seasonal occurrence of benthic algae and changes of subtidal vegetation were studied for their species composition, diversity and biomass during 1982 and 1983 at several selected sites at Juckdo Island (38$^{\circ}$12'N, 128$^{\circ}$32'E), eastern coast of Korea. Three large brown algae which played a role in change of algal vegetation through their great biomass were investigated with regard to their seasonal growth. Large brown algae such as Undaria pinnatifida, Costaria costata, Laminaria japonica, Agarum cribrosum, Sargassum confusum and S. hornerii constitute the major portion of vegetation in this area throughout the year. Algal vegetation in spring time is characterized by dominance of species U. pinnatifida and C. costata, whereas the summer vegetation by S. confusum and S. hornerii. In autumn large brown algae are shedded and only small algae, such as Chondrus ocellatus and Grateloupia filicina, remain. The vegetation in winter is dominated by the growth of U. pinnatifida and C. costata. Monthly changes in mean length and weight of randomly collected U. pinnatifida, C. costata and S. confusum are as follows; U. pinnatifida occurs from December to June and shows their maximum growth during March (120 cm in length, 201 g/individual in wet weight), its maximum growth rate is 1.4 cm/day, 3.3 g/day in this month. The growth season of C. costata is very similar to U.pinnatifida, but their average maximum length(110 cm) and weight (106 g/ind.) are lower than U. pinnatifida. The greatest growth rate is during March (1.8 cm/day, 2.0g/day). S. confusum is present throughout the year and reaches the maximum growth (102 cm, 63g/ind.) in July. Maximum growth rate (1.5 cm/day, 1.2 g/day) occurs also during this month. U. pinnatifida and C. costata show different months of maximum growth evidently during the two year. This seems to be caused by a considerable damage to the local vegetation followed by heavy storm in February 1983.

• ALGAE
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• 제34권2호
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• pp.153-162
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• 2019

Anthropogenic disturbances, including coastal habitat modification and climate change are threatening the stability of kelp beds, one of the most diverse and productive marine ecosystems. To test the effect of temperature and irradiance on the microscopic gametophyte and juvenile sporophyte stages of the rare kelp, Saccharina angustissima, from Casco Bay, Maine, USA, we carried out two sets of experiments using a temperature gradient table. The first set of experiments combined temperatures between $7-18^{\circ}C$ with irradiance at 20, 40, and $80{\mu}mol\;photons\;m^{-2}\;s^{-1}$. The second set combined temperatures of $3-13^{\circ}C$ with irradiance of 10, 100, and $200{\mu}mol\;photons\;m^{-2}\;s^{-1}$. Over two separate 4-week trials, in 2014 and again in 2015, we monitored gametogenesis, the early growth stages of the gametophytes, and early sporophyte development of this kelp. Gametophytes grew best at temperatures of $8-13^{\circ}C$ at the lowest irradiance of $10-{\mu}mol\;photons\;m^{-2}\;s^{-1}$. Light had a significant effect on both male and female gametophyte growth only at the higher temperatures. Temperatures of $8-15^{\circ}C$ and irradiance levels of $10-100{\mu}mol\;photons\;m^{-2}\;s^{-1}$ were conditions for the highest sporophyte growth. Sporophyte and male gametophyte growth was reduced at both temperature extremes-the hottest and coldest temperatures tested. S. angustissima is a unique kelp species known only from a very narrow geographic region along the coast of Maine, USA. The coupling of global warming with high light intensity effects might pose stress on the early life-history stages of this kelp, although, as an intertidal species, it could also be better adapted to temperature and light extremes than its subtidal counterpart, Saccharina latissima.

• 한국지형학회지
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• 제25권2호
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• pp.43-61
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• 2018

Heterogeneous sedimentary deposits with different soil colors and various degree of hardness are exposed in its foredune and tidal zone due to the effects of recently accelerated coastal erosion along the Ujeon Coast in Jeung-do, Shinan-gun. This study was conducted on the assumption that these sedimentary deposits were developed in different timing and environments. Thus, we can infer the geomorphic development processes of the area based on evidences like the physicochemical characteristics of each sedimentary layer. Several analysis of these sedimentary depositssuch as grain size analysis, X-ray Fluorescence Measurement (XRF), and Loss on ignition (LOI) were performed on central (Ujeon A) and southern (Ujeon B) parts of the Ujeon Coast. I found that the foredune sedimentary deposits have four stages of geomorphic development processes. In the initial stage of development, during the peak of the Last Interglacial Period (MIS 5e), basal deposits were accumulated in the low-energy environment of subtidal zones. In the second stage, during the Last Glacial Period (MIS 4~MIS 2), eolian sedimentary layers were developed by terrestrial aeolian processes by which fine materials were transported from the Yellow Sea which became a dry land exposed by lowered sea level. In the third stage, various mechanism existed for the formation of each sedimentary layer. In the region of Ujeon A, sedimentary layers were developed in the littoral zone environment dominated by marine processes during the maximum phase of transgression in the Holocene. Meanwhile, the region of Ujeon B began to form eolian sedimentary layers during MIS 2. In the last stage, thick coastal dune deposits, covered all over the Ujeon Coast. During the late Holocene (0.7~0.6 ka), terrestrial processes kept dominating the region, developing typical eolian sedimentary layers.

• Ocean and Polar Research
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• 제44권4호
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• pp.331-338
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• 2022

The high latitude scleractinian coral Alveopora japonica Eguchi, 1965 occurs in high density in the shallow rocky subtidal in Jeju Island, forming coral carpets. Despite its ecological role providing a unique habitat for other benthic organisms, the benthic fauna associated with the A. japonica coral carpet is poorly known. To identify fauna associated with the coral carpet, we explored three sites dominated by A. japonica and one control site on northwestern Jeju Island in May 2013. Using SCUBA, we collected A. japonica and the epibenthic mega-fauna associated with the colonies in 1×1 m² and identified them to the species level. At a depth of 10 to 15 m, A. japonica colonies heavily covered the seafloor, forming a layer called a coral carpet, with a density of 94 (Keumneung-ri), 133 (Biyangdo), and 155 (Gwidok-ri) colonies/m². Thirty-four molluscan species were identified from the four sites, including 20 bivalves and 14 gastropods. The coral carpets were enriched with sessile bivalves compared to the control site, as we identified twenty bivalve and eight gastropod species from the coral carpets. Most bivalve species associated with the coral carpets had tropical-subtropical affinities, while gastropods were mainly subtropical and subtropical-low boreal species. Leiosolenus lischkei M. Huber, 2010, in the family Mytilidae and Barbatia steamsi (Pilsbry, 1895), in the family Arcidae, were the two most abundant bivalve species in the coral carpet, L. lischkei being a borer, and B. stearnsi a nestler. The tropical to subtropical Pacific star shell Astralium haematragum (Menke, 1829)was the most abundant gastropod at the study sites. The bivalves and gastropods associated with the coral carpet were small-sized juveniles or sub-adults, suggesting that the coral carpet provides a micro-habitat for the bivalves and gastropods.

• 현장농수산연구지
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• 제17권1호
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• pp.45-56
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• 2015

2017년도 여수 금오도에서 패조류 어초설치와 해조번식을 위한 베드장 조성을 위하여 해조류 생물상 조사한 결과 해조류 출현종은 녹조류 4종, 갈조류 9종, 홍조류 15종으로 총 30종이 출현하였으며 현존량도 1600~4000g/m²로 같은 시기의 다른 지역보다 높게 나타났다. 상부인 조간대에서는 출현종수와 우점도가 가장 높게 나타났으며 조하대인 수심 1~3m에서는 해조류 현존량이 높은 것으로 나타났다. 그러나 수심 4~6m의 하부에서는 출현종, 우점도 및 현존량 모두 낮게 나타났다. 본 조사시 나타난 특징은 금오도 지역은 조하대 수심 4~6m권에서 갯녹음현상 발생으로 해조류 군집이 급격이 감소되어 이 해역에 해조류형 어초나 해조배드를 설치하여 자원량을 증강시키는 것이 필요 할 것으로 사료되었다. 또한 해조류형 어초시설의 경우 투하시기는 해조류의 포자가 방출되기 전인 시기인 초봄시기에 시설되는 것이 바람직 할 것으로 생각되며 수심은 보상심도가 유지되는 3~6m권내에 설치 될 수 있도록 하는 것이 효율적이라고 판단된다.

• 한국수산과학회지
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• 제57권3호
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• pp.262-277
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• 2024

The mid-eastern coast of Korea is located at the boundary between cold and warm currents, which causes changes in the distribution and composition of marine organisms in response to fluctuations in the marine environment. To understand the seasonal changes in the seaweed community, we investigated its species composition, biomass, coverage, and frequency from November 2022 to August 2023. A total of 45 species (7 green, 18 brown, and 20 red algae) were found in the study area. In the intertidal zone, the number of species decreased from autumn to summer; the biomass peaked during winter (471.94 g wet weight m^-2). Seaweed groups were the dominant functional groups, which were coarsely branched, filamentous, and sheet-like during autumn, winter, spring, and summer. The morpho-functional group was dominated by turf species. In the subtidal zone, the number of species increased during autumn to spring, whereas the biomass peaked during spring (655.27 g wet weight m^-2). The functional group was dominated by coarsely branched species throughout all four seasons, whereas the morpho-functional group was dominated by canopy species. Consequently, changes in the biomass of brown and red algae are recognized as key drivers of seasonal changes in seaweed communities.