• 제목/요약/키워드: subtidal zone

검색결과 137건 처리시간 0.027초

만재도의 한국미기록 유낭류(태형동문문, 순구목) 2종 (New Record of Two Ascophoran Species (Bryozoa, Cheilostomata) from Manjaedo Island, Korea)

  • Seo, Ji-Eun
    • Animal Systematics, Evolution and Diversity
    • /
    • 제16권2호
    • /
    • pp.213-218
    • /
    • 2000
  • 만재도의 조하대로부터 1988년 8월 23일에 채집된 태형동물을 분류한 결과 맞채찍이끼벌레 (Crepidacantha poissoni)와 항아리이끼벌레 (Hippothoa distans)의 2종이 한국미기록종으로 밝혀졌다. 채찍이끼벌레과 (Crepidacanthidae)는 우리나라에서 처음으로 보고된다.

  • PDF

Sample Size Determination for the Estimation of Population Density of Marine Benthos on a Tidal Flat and a Subtidal Area, Korea

  • Koh, Chul-Hwan;Kang, Seong-Gil
    • Journal of the korean society of oceanography
    • /
    • 제33권3호
    • /
    • pp.113-122
    • /
    • 1998
  • The requisite numbers of sample replicates for the population study of soft-bottom benthos were estimated from survey data on the Songdo tidal flat and subtidal zone in Youngil Bay, Korea. Large numbers of samples were taken; two-hundred-fifty 0.02 m$^2$ box corers and fifty 0.1m$^2$ van Veen grabs were taken on the Songdo tidal flat and in Youngil Bay, respectively. The effect of sampler size on sampling efforts was investigated by pooling the unit samples in pairs, fours, eights, etc. The requisite number of sample replicates (n$_r$) was determined by sample variance (s$^2$) and mean (m) function (n$_r$:s$^2$/P$^2$m$^2$), at P=0.2 level, in which s$^2$ and m were calculated from the counts of individuals collected. For example, seven samples of 0.02 m$^2$ corer for the intertidal and two samples of 0.1 m$^2$ van Veen grab for subtidal fauna were required to estimate the total density of community. The smaller sampler size was more efficient than larger ones when sampling costs were compared on the basis of the total sampling area. The requisite number of sample replicates was also predicted ($\^{n}$n$_r$) by substituting $\^{s}$$^2$ obtained from the regression of s$^2$ against m using the Taylor's power law ($\^{s}$$^2$:am$^b$). The regression line of survey data on s$^2$ and m plotted on log scale was well fitted to the Taylor's power law (r$^2$${\geq}$0.95, p<;0.001) over the whole range of m. The exponent b was, however, varied when it was estimated from m which was categorized into classes by its scale. The fitted exponent b was large when both density class and the sampler size were large. The number of sample replicates, therefore, could be more significantly estimated, if regression coefficients (a and b) would be calculated from sample variance and mean categorized into density classes.

  • PDF

섬진강 하구에 자생하는 잘피의 분포 현황 및 생태적 특성 (Spatial Distribution and Ecological Characteristics of Zostera marina and Zostera japonica in the Seomjin Estuary)

  • 김정배;박정임;최우정;이재성;이근섭
    • 한국수산과학회지
    • /
    • 제43권4호
    • /
    • pp.351-361
    • /
    • 2010
  • Among common estuarine submerged plants, seagrasses are the most extensively studied due to their ecological importance in estuarine ecosystems. Seagrass meadows are important biological habitats for a wide variety of marine animals and plants. They are a source of organic carbon for commercially important animals. Furthermore, seagrasses act as nutrient filters in estuarine and coastal marine ecosystems. As such, mapping the distribution of seagrass beds is important for management and conservation strategies. In order to survey the seagrass distribution within the Seomjin Estuary, We directly observed seagrass beds in Kwangyang and Hadong using SCUBA. The distribution area, species composition, morphology, density, biomass and productivity of seagrass meadows were examined. Seagrass meadows were distributed in the intertidal and subtidal zones of the Galsa tidal flats, and in the subtidal zone of the neighboring POSCO area. Patches of Zostera japonica was found at patches at the Galsa tidal flats intermediate point. The total estimated seagrass distribution area of the Seomjin Estuary was $1.84\;km^2$. Of the total, $1.83\;km^2$ was Zostera marina (eelgrass) and $0.01\;km^2$ was Zostera japonica (dwarf eelgrass). Zostera japonica was found in intertidal zones. Zostera marina was found from the intertidal to subtidal zones at a 2 m mean sea level (MSL) depth. The leaf productivity of Zostera marina was $4.47g\;DW\;m^{-2}\;day^{-1}$. The annual production of eelgrass was $1,632\;g\;DW\;m^{-2}\;yr^{-1}$, which corresponds to $731g\;C\;m^{-2}\;yr^{-1}$. The total production of eelgrass was $3,002\;tons\;DW\;yr^{-1}$, which corresponds to $1,343\;tons\;C\;yr^{-1}$.

수정된 사진방형구법을 이용한 조하대 해조류의 군집구조 분석 (An Analysis of Subtidal Macroalgal Community Structure Using a Modified Photo Quadrat Method)

  • 김영대;박미선;문태석;안중관;김수지;김영환
    • 한국수산과학회지
    • /
    • 제44권3호
    • /
    • pp.298-307
    • /
    • 2011
  • The species composition and distributions of subtidal marine algae on the east coast of Korea were studied. We examined all species found in permanent quadrats at three depths (3 m, 5 m and 10 m) at Sacheon between October 2008 and December 2009. Coverage and frequency data were collected monthly via underwater photography and analyzed using a modified photo quadrat method. Of the 82 species identified, 10 were chlorophytes, 21 were phaeophytes, 50 were rhodophytes, and one was a seagrass. The largest number of species (59) was found 10 m deep, while the fewest (39) species were present at 5 m. A total 17 species (two green, five brown, and 10 red algae) occurred at all three depths. The vertical distribution of the study site was characterized by the melobesioidean algae, Ulva pertusa, Sargassum confusum, Phyllospadix iwatensis, and Codium arabicum at 3 m deep, melobesioidean algae and U. pertusa at 5 m deep, and Corallina pilulifera, Prionitis cornea, Chondracanthus tenellus and melobesioidean algae at 10 m deep. Given that coralline algae such as melobesioidean algae and C. pilulifera play important roles in coastal ecosystems, thorough studies on the spatial and temporal variations of coralline algae and the dynamics of marine algal communities on the east coast of Korea are now required.

제주 가파도 해역의 조하대 해조상 및 군집구조의 연간 변동 (Annual Variation of Macroalgal Flora and Community Structure in the Subtidal Zone at Gapado Island, Jeju, Korea)

  • 김보연;한송헌;이승종;고준철
    • 한국수산과학회지
    • /
    • 제57권1호
    • /
    • pp.79-87
    • /
    • 2024
  • We seasonally examined marine macroalgal community structures in the subtidal zones at Gapado Island, Jeju, Korea, from February 2013 to November 2019. A total of 164 macroalgal species were identified, including 15 green, 40 brown, and 109 red algae. Species richness ranged from 54-106 species, with the maximum observed in 2013 and the minimum observed in 2015. Cladophora wrightiana var. minor, Ecklonia cava, Amphiroa anceps, Corallina aberrans, Corallina crassisima, Synarthrophyton chejuense, Sonderophycus capensis and Plocamium telfairiae occurred in all seasons. The average annual seaweed biomass was 1,258.22 g wet wt./m2, ranging from 917.51 g/m2 in 2017 to 1,551.95 g/m2 in 2014. E. cava was the most dominant species, accounting for 46.57% of the total seaweed biomass. The subdominant species were P. telfairiae and A. anceps, comprising 8.64% (108.75 g/m2) and 6.65% (83.61 g/m2) of the total biomass, respectively. The vertical distribution of subtidal seaweeds were represented by E. cava and P. telfairiae at 5-20 m, A. anceps at 10-20 m, C. aberrans and C. crassisima at 5 m and C. wrightiana var. minor at 10 m. Cluster analysis revealed three distinct groups: group A (2014-2018), group B (2019) and group C (2013), indicating significant differences in the annual seaweed community.

Morphological variability of intertidal Eisenia arborea (Laminariales, Ochrophyta) at Punta Eugenia, Baja California Sur

  • Parada, Gloria M.;Riosmena-Rodriguez, Rafael;Martinez, Enrique A.;Hernandez-Carmona, Gustavo
    • ALGAE
    • /
    • 제27권2호
    • /
    • pp.109-114
    • /
    • 2012
  • Water motion is one of the main drivers in morphological variability in species within de order Laminariales, and most of our current knowledge is based on subtidal populations. $Eisenia$ $arborea$ is a dominant kelp species in the North Pacific, widely distributed along the Baja California Peninsula from mid intertidal down to subtidal areas. This species presents great variability in the intertidal zone but it has not been yet evaluated such variability according to wave exposure. The present work also identifies the spatial / temporal variation, particularly respect to the presence of stipes without medulla (hollow stipes) a feature common among other brown seaweeds. We evaluated the effects of wave action in morphological variation of intertidal $Eisenia$ $arborea$ (Laminariales, Ochrophyta) at Punta Eugenia. The spatial and temporal variation sampling was surveyed between February, May, July, and August 2004 in the intertidal of Punta Eugenia, Baja California Sur. Our results have shown that exposed sites correlate with increased length and width of stipes as compared to more protected sites. Hollow stipes frequency changed more in association with temporal variation than with spatial heterogeneity suggesting nutrient limitation for thalli development. Our results suggest that $Eisenia$ $arborea$ compensate by morphological modifications the stress of living in the intertidal zone by showing larger stipes. Hollow stipes might be are also a mechanical adaptation to increase survival in high energy environments.

강화 남부 갯벌의 유공충 특성 (Foramniferal Characteristics in the Ganghwa Tidal Flat)

  • 우한준;이연규
    • 한국습지학회지
    • /
    • 제8권3호
    • /
    • pp.51-65
    • /
    • 2006
  • 연구지역에서 2003년 8월에 199개 정점에서 표층퇴적물을 채취하여 분석하였다. 표층 퇴적물은 6개의 퇴적상으로 구성되어 있었다. 일반적으로 모래 펄 퇴적물이 강화 남단 갯벌에서 우세하였고 모래 퇴적물은 강화도 서부의 수로와 조하대에서 우세하였다. 이 지역의 1997년 퇴적상과 비교하여 모래펄 퇴적물은 갯벌의 동쪽으로 확장 되었다. 강화 남단 갯벌과 주변부 30 정점의 표층퇴적물에서 살아있는 유공충 34종을 포함하여 총 61종의 유공충이 확인되었다. 살아있는 유공충에서는 Ammonia beccarii와 Elphidium etigoense, 전체군집에서는 Ammonia beccarii, Elphidium etigoense, Jadammina sp.와 Textularia earlandi가 연구지역에 넓게 분포한다. 일반적으로 개체수와 종 다양성은 갯벌의 서부에서 상대적으로 높은 수치를 나타냈다. 전체 유공충 군집의 집괴분석 결과 4개의 생물상으로 구분되었다. 생물상 1은 강화 남단의 동부 갯벌, 생물상 4는 강화 남단의 서부 갯벌의 저서환경을 나타냈다. 생물상 3은 생물상 1과 4의 전이환경으로 보여 진다.

  • PDF

인공구조물 건설 후 안면도 가경주 간석지의 퇴적환경 및 미지형변화 분석 (Analysis of Sedimentary Environment and Micro-Landform Changes Afterthe Construction of Artificial Structuresin the Tidal Flat of Anmyeondo Gagyeongju, Western Coast of Korea)

  • 장동호;류주현
    • 한국지형학회지
    • /
    • 제25권1호
    • /
    • pp.31-45
    • /
    • 2018
  • This study investigated the characteristics of sedimentary environment changes across a tidal flat in Gagyeongju of Anmyeondo Island. We performed a spatio-temporal analysis on the grain sizes composition of sediments and micro-landform changes during the winter from 2013 to 2016. The results showed that erosion was a dominant processthroughout the study flat, reducing the surface elevation even by 1 m around the upper sand flat. As a consequence, headlands have formed in the entire region of Gagyeongju village. In addition, erosion quickly progressed along the low-lying subtidal zone and tide way and, in contrast, sedimentation progressed in the mid-elevation tidal flat. We posit that a jetty, which had been constructed as a pier facility on the eastern part of the study area, interfered with the flow of tidal current, thereby enhancing these erosional processes. This is because such interference can block the supply of fine-textured sediments from the nearby Cheonsu Bay and therefore reduce surface elevation. According to the surface sediment analysis, the sediments were categorized into 7 sedimentary facies, and generally displayed a high ratio of silt and clay. The result of time-series analysis (2012-2013) showed that the sediments on the tidal flat became fine-grained, and that sorting became worse. However, the sediments on the subtidal zone, embayment and along inside of the jetty tended to be coarse-grained. In conclusion, the tidal flat microlandform change in the study area was caused by a disruption in the seawater circulation due to the jittery construction within the tidal flat, which had a direct effect on erosional and sedimentary environment processes.

牙山灣海底의 底棲有孔蟲 (BENTHIC FORAMINIFERA OF THE SUBTIDAL ZONE OF ASAN BAY, KOREA)

  • 장순근
    • 한국해양학회지
    • /
    • 제18권2호
    • /
    • pp.125-141
    • /
    • 1983
  • 牙山灣 및 주변海底에서 1982 5-6월에 걸쳐서 採取한 表面堆積物 132점에서 現生底棲有孔蟲의 生, 全體群集에 따르는 造成, 分布, 有孔蟲 個體數 相對的 率, 多樣性, 皮穀의 救助 등 微古生物學的 特性을 硏究했다. 같이 産出되는 化石으로 推定되는 交代된 有孔蟲을 包含하여 皮穀의 保存狀態가 불량한 群集의 造成, 多樣性 및 生群集과의 관계 등을 연구했다.

  • PDF

강릉 사근진 해역의 해산식물 군집구조 특성 (Characteristics of Subtidal Marine Plant Community Structure at Gangneung Sageunjin in the East Coast of Korea)

  • 김영대;안중관;박미선;김현겸;민병화;연수영;김영환
    • 한국환경과학회지
    • /
    • 제22권6호
    • /
    • pp.761-771
    • /
    • 2013
  • The species composition and variation of marine plants at Saguenjin in the east coast of Korea were investigated monthly from October 2008 to December 2009. As a result, 92 species of marine plants identified, 91 species were seaweeds (7 green algae, 22 brown algae, 62 red algae) and 1 were sea grass. Dominant species in importance value were melobesioidean algae, Ulva pertusa and Phyllospadix iwatensis. The vertical distribution of algae were characterized by melobesioidean algae, U. pertusa at 3 m depth, melobesioidean algae, P. iwatensis and U. pertusa at 5 m depth and melobesioidean algae, Chondrus ocellatus and Prionitis cornea at 10 m depth.