• Title/Summary/Keyword: the Southern coast

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A unique genetic lineage at the southern coast of China in the agar-producing Gracilaria vermiculophylla (Gracilariales, Florideophyceae)

  • Hu, Zi-Min;Liu, Ruo-Yu;Zhang, Jie;Duan, De-Lin;Wang, Gao-Ge;Li, Wen-Hong
    • ALGAE
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    • v.33 no.3
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    • pp.269-278
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    • 2018
  • Ocean warming can have significant negative impacts on population genetic diversity, local endemism and geographical distribution of a wide range of marine organisms. Thus, the identification of conservation units with high risk of extinction becomes an imperative task to assess, monitor, and manage marine biodiversity for policy-makers. Here, we surveyed population structure and genetic variation of the red seaweed Gracilaria vermiculophylla along the coast of China using genome-based amplified fragment length polymorphism (AFLP) scanning. Regardless of analysis methods used, AFLP consistently revealed a south to north genetic isolation. Populations at the southern coast of China showed unique genetic variation and much greater allelic richness, heterozygosity, and average genetic diversity than the northern. In particular, we identified a geographical barrier that may hinder genetic exchange between the two lineages. Consequently, the characterized genetic lineage at the southern coast of China likely resulted from the interplay of post-glacial persistence of ancestral diversity, geographical isolation and local adaptation. In particular, the southern populations are indispensable components to explore evolutionary genetics and historical biogeography of G. vermiculophylla in the northwestern Pacific, and the unique diversity also has important conservation value in terms of projected climate warming.

Predicting the Invasion Pathway of Balanus perforatus in Korean Seawaters

  • Choi, Keun-Hyung;Choi, Hyun-Woo;Kim, Il-Hoi;Hong, Jae-Sang
    • Ocean and Polar Research
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    • v.35 no.1
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    • pp.63-68
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    • 2013
  • The European Common Barnacle Balanus perforatus Brugiere (Crustacea, Cirripedia) has been introduced into the east coast of Korea, presumably via the ballast water of ships. The species has since been spreading along both the northern and southern coast to the east, most likely due to alongshore currents. We predicted the potential range expansion of Balanus perforatus in Korean waters using Genetic Algorithm for Rule-set Prediction (GARP), an environmental niche modeling technique. The results show that much of the southern coastal waters of Korea could be colonized by the spread of the nonindigenous species, but that the west coast is unlikely to be invaded. More sampling on the west coast would enhance the predictability of the model. To our knowledge, this is the first report of its kind for predicting marine nonindigenous species in Korean waters using GARP modeling.

New Record of Sargassum filicinum Harvey (Fucales, Phaeophyceae) in the Pacific Coast of Mexico

  • Aguilar-Rosas, Luis E.;Aguilar-Rosas, Raul;Kawai, Hiroshi;Uwai, Shinya;Valenzuela-Espinoza, Enrique
    • ALGAE
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    • v.22 no.1
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    • pp.17-21
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    • 2007
  • Sargassum filicinum Harvey, a brown alga (Phaeophyceae) native to Northeastern Asia, has been recently reported from the coast of Southern California (USA). Here we report the occurrence and range extension of this introduced species, as we found the alga at La Jolla and Rancho Packard in Todos Santos Bay, Baja California, Mexico. The first collections of S. filicinum correspond to several immature plants, found on September 8, 2005, drifting in the intertidal zone at La Jolla. Later on November 9, 2006, we found a well-established population in Rancho Packard in the middle intertidal zone to 2 m depth. Since S. filicinum is an annual monoecious species with air bladders, the risk there is a high risk of spreading rapidly along the Pacific, as in the case for S. muticum. The population in Rancho Packard extends 500 m along the coast, consisting mainly of young plants with an average length of 30 cm and a density of 5 thallus/m2. This is the first record of this invasive species for the Mexican Pacific coast, and it represents the southern limit along the Pacific coast of North America. This finding suggests that this invasive species has successfully colonized the Pacific coast of North America and its distributional range is still expanding.

Two Brackish Cyclopoid Copepods from Southern Coast of Korea

  • Yoon, Hong-Ju;Chang, Cheon-Young
    • Animal Systematics, Evolution and Diversity
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    • v.24 no.3
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    • pp.241-250
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    • 2008
  • Two brackish cyclopoid species are reported mostly from the estuaries and salt marshes in the southern coast of Korea: Limnoithona sinensis (Burckhardt, 1913) and Apocyclops borneoensis Lindberg, 1954. The two species as well as the genera are newly added to Korean fauna. Herein, the redescription is provided with the systematic accounts and detailed illustrations of them.

Marine Macro-algae of Orissa, East Coast of India

  • Rath, Jnanendra;Adhikary, Siba Prasad
    • ALGAE
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    • v.21 no.1
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    • pp.49-59
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    • 2006
  • A total of twenty one species of marine macro-algae were reported from 460 kms long Orissa coast in the east coast of India. Of these 9 species belongs to Chlorophyta, 2 to Phaeophyta and 10 to Rhodophyta. The low species richness compared with southern and western coasts of India was due to lack of rocky and/or coral substratum. Enteromorpha usneoides and Gelidium divaricatum were reported first from India. Enteromorpha linza, E. clathrata, Colpomenia sinuosa, Dictyota dichotoma, Catenella impudica, Compsopogon aeruginosus and Grateloupia lithophila were the new records for Orissa coast.

Characteristics of the Land and Sea Breeze on Cheju island , Korea (제주도 지방의 해륙풍의 특성)

  • 김유근
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.27 no.1
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    • pp.41-55
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    • 1991
  • A study was done to investigate characteristics of the land and sea breeze over Cheju island on the basis of surface meteorological data collected from 1977 to 1986. The results are summarized as follows: The frequency of the land and sea breze was highest in August followed by September, October, May and November in descending order. This indicates that the frequency of the land and sea breeze is higher in fall than in spring, and lowest in winter. The sea breeze began much earlier than any other regions of Korea all the year round, and it began about 30 minutes earlier and ended one hour later in the northern coast than in the southern coast of Cheju island. Meanwhile, the land breeze began about one hour earlier in the southern coast than in the northern coast and ended almost at the same time in both coasts. The annual mean duration of the sea breeze was about one hour longer in the northern coast than in the southern coast, but the land breeze showed an opposite trend. The duration of the sea breeze was longer in summer than in winter and again the land breeze was opposite. Transition period from the sea to the land breeze was relatively long in summer and shout in winter, but transition period from the land to the sea breeze was not different between seasons. The time for a maximum velocity of the sea breeze came earlier in the southern coast than in the northern coast, but that of the land breeze came almost at the same time in both coasts with no seasonal variations. Monthly mean maximum velocity of the sea breeze was greater than that of the land breeze.

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Hydrocarbon Source Rock Potential of Eocene Forearc and Subduction Zone Strata, Southern Oregon Coast Range, U.S.A. (미국 오레곤 남부 에오세 전호상 및 섭입대 퇴적층의 탄화수소 근원암 가능성)

  • Ryu, In-Chang
    • The Korean Journal of Petroleum Geology
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    • v.11 no.1 s.12
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    • pp.27-41
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    • 2005
  • The hydrocarbon source rock potential of the Eocene units in the southern Oregon Coast Range was evaluated by using the Rock-Eval pyrolysis. Most Eocene units in southern Oregon Coast Range are thermally immature and contain lean, gas-prone Type III kerogen. However, some beds(coals) are sufficiently organic-rich to be sources of biogenic and thermogenic methane discovered in numerous seeps. The overall hydrocarbon source rock potential of the southern Oregon Coast Range is moderately low. Several requirements for commercial accumulations of hydrocarbon, however, probably exist locally within and adjacent areas. Three speculative petroleum systems are identified. The first includes the southern part of the Oregon Coast Range near the border with the Mesozoic Klamath Mountains and is related to a proposed subduction zone maturation mechanism along thrust faults. The second is centered in the northern part of the range and may be associated with basin-centered gas in an over-pressured zone. The third occurs near the eastern border of the range where maturation is related heating by sills and migration of hydrothermal fluids associated with mid-Tertiary volcanism in the Western cascade arc.

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Spatial and Temporal Distribution of Fish Larvae in the Southern Coast of Korea from Spring to Summer (봄과 여름철 남해안 자치어의 시·공간적 분포)

  • Moon, Seong Yong;Lee, Mi Hee;Jung, Kyung Mi;Kim, Heeyong;Jung, Jin Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.55 no.4
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    • pp.461-477
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    • 2022
  • We investigated the community structure and performed detailed characterization of fish larvae assemblages collected from the southern coast of Korea in the spring and summer of 2021. The total abundance of fish larvae varied from 193.6 to 1,915.6 ind. 10 m-3. The species were distributed across 10 orders with 23 families, and 41 taxa. The dominant taxa were Gobiidae spp., Engraulis japonicus, Nibea albiflora, Sebastiscus spp., Callionymus valenciennei, Pennahia argentata, Sebastes thompsoni, Parablennius yatabei, and Platycephalus indicus. Engraulis japonicus individuals were collected from April to August and their presence contributed greatly to the total abundance of fish larvae. The total number and abundance of species peaked in early summer and the Shannon-Weaver index was in the range 0.11-1.49. Redundancy analyses revealed that the major environmental factors affecting the fish larvae assemblage differed according to the dominant taxa. Water temperature, zooplankton density, and Paracalanus parvus s. l. density were the key factors affecting the spatial and temporal distribution of fish larvae in the southern coast of Korea in spring and summer.

Spatial and Temporal Distribution and Characteristics of Zooplankton Communities in the Southern Coast of Korea from Spring to Summer Period (봄과 여름철의 남해안 동물플랑크톤 시·공간적 분포와 군집 특성)

  • Moon, Seong Yong;Lee, Mi Hee;Jung, Kyung Mi;Kim, Heeyong;Jung, Jin Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.55 no.2
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    • pp.154-170
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    • 2022
  • The zooplankton composition, abundance, community structure, and species diversity in the major commercial fishery species spawning grounds in the southern coast of Korea were investigated in this study. A total of 80 taxa were sampled, with the mean abundance range of 5,612-11,720 ind. m-3 and the mean biomass range of 41.6-1,086.8 mg m-3. The dominant species were Paracalanus copepodites, Paracalanus parvus s. l., Oithona copepodites, Paracalanus nauplii, Noctiluca scintillans, Oithona similis, and Ditrichocorycaeus affinis. The species diversity indices were highest in August, suggesting that diversity is influenced by neritic and oceanic warm-water species. A cluster analysis with non-metric multidimensional scaling (nMDS) revealed three groups of zooplankton communities. The April and May samples clustered into Group A, having the highest mean total zooplankton abundance and lowest species diversity, consisting mainly of temperate species located in the middle region of the southern coast of Korea. Cluster Group B was from the early summer season (June) and contained the highest species diversity with some oceanic and neritic zooplankton species. Cluster Group C from the summer season (July and August) mainly comprised P. parvus s. l. and O. similis. The redundancy analysis (RDA) indicated that abundance is positively correlated with salinity, and chlorophyll-a concentrations.