• 제목/요약/키워드: mangrove

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On the Seedling Time of the Mangrove Oyster, Crassostrea rhizophorae, in the Lagoon of Cocineta in Venezuela (Venezuela국 Cocineta호산 Mangrove oyster의 채묘시기)

  • YOO Sung Kyoo;CHO Chang Hwan;YOO Myung-Suk
    • Korean Journal of Fisheries and Aquatic Sciences
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    • 제9권4호
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    • pp.281-285
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    • 1976
  • An investigation on the breeding time of the Mangrove oyster, Crassostrea rhizaphorae, in the lagoon of Cocineta which is located in the northwestern part of Venezuela was carried out from February through May in 1976. Surface water temperature was high, over $25^{\circ}C$ and specific gravity was around 1.0258. Transparency to water depth varied between 29 and $80\%$. The range of water content of the oysters increased from February through May. However, the averge monthly range of water content varied only slightly from 80.67 to $82.25\%$. From the numbers of matured planktonic larvae together with total numbers of planktonic larvae found, we may assume that the best seedling period is from late April through early May. We may also assume that the best area is around stations 4 and 3, station 3 being slightly better than station 4.

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Tracing the origin of fish without hatchery information: genetic management of stock enhancement for mangrove red snapper (Lutjanus argentimaculatus) in Taiwan

  • Hsu, Te-Hua;Huang, Chang-Wen;Lin, Cheng-Hui;Lee, Hung-Tai;Pan, Chieh-Yu
    • Fisheries and Aquatic Sciences
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    • 제23권5호
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    • pp.13.1-13.7
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    • 2020
  • Stock enhancement is considered to be a valuable approach for restoring fishery resources. Because no specific official institution in Taiwan is responsible for the production of fry, the released fry are purchased directly from the private sector. However, fishermen from the private industry have not established a genetic background, so the genetic composition for each batch of released fry is unclear. Mangrove red snapper (Lutjanus argentimaculatus), a prominent species released in Taiwan, was collected after its official release. One hundred and two field samples were compared with four batches of hatchery fry (n = 685) by using a microsatellite-based multiplex PCR assay. Four of the field samples (3.9%; 4/102) were revealed to be from a fish farm and most likely from a single batch. This study revealed that wild mangrove red snappers are genetically different from those originating from farms, and their origins can be traced through molecular markers, even without information on breeding stocks.

Observations on some mangrove-associated algae from the western Pacific (Guam, Chuuk, Kosrae, and Pohnpei)

  • West, John A.;Kamiya, Mitsunobu;Loiseaux de Goer, Susan;Karsten, Ulf;Zuccarello, Giuseppe C.
    • ALGAE
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    • 제28권3호
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    • pp.241-266
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    • 2013
  • The mangrove algal flora of Guam and the Federated States of Micronesia has been poorly explored. We add to our knowledge of this region by observations of collections from these regions. This paper presents new and additional records of: Rhodophyta-Acrochaetium globosum, Colaconema sp., Caulacanthus indicus, Bostrychia moritziana / B. radicans, B. radicosa, B. simpliciuscula, B. kelanensis and B. tenella, Murrayella periclados, and Caloglossa ogasawaraensis; Chlorophyta-Boodleopsis carolinensis; and Phaeophyceae-Dictyota adnata, Dictyotopsis propagulifera, and Canistrocarpus cervicornis. Most specimens were cultured to investigate their reproductive biology and many specimens were further identified using molecular data. Low molecular weight carbohydrates (dulcitol, sorbitol, and digeneaside) were identified in samples of B. radicosa and B. simpliciuscula. We also present data on manganese-rich deposits found on B. simpliciuscula and B. tenella in culture, possibly formed by epiphytic bacteria.

Preliminary evaluation of some medicinal plants of Sundarbans mangrove forest on central nervous system

  • Alamgir M;Alam SMS;Alaul M;Rashid M;Hasan M;Choudhuri MSK
    • Advances in Traditional Medicine
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    • 제6권3호
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    • pp.215-220
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    • 2006
  • The Sundarbans mangrove forest has a rich biodiversity of flowering plants and many of these have been used in traditional medicine although the flora remains comparatively uninvestigated scientifically. Xylocarpus granatum, Xylocarpus moluccensis and Excoecaria agallocha methanolic extract showed a central nervous system depressant activity on the hole cross and open field test at 800 mg/kg dose level. The most significant depressant activity was observed in Xylocarpus granatum followed by Xylocarpus moluccensis and Excoecaria agallocha. There was no depressant activity observed in the models for Sarcolobus globosus. Further studies are required to confirm the activity and to explain the mechanism.

Landscapes and Ecosystems of Tropical Limestone: Case Study of the Cat Ba Islands, Vietnam

  • Van, Quan Nguyen;Duc, Thanh Tran;Van, Huy Dinh
    • Journal of Ecology and Environment
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    • 제33권1호
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    • pp.23-36
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    • 2010
  • The Cat Ba Islands in Hai Phong City, northern Vietnam, consist of a large limestone island with a maximum height of 322 m above sea level and 366 small limestone islets with a total area of about $180\;km^2$. The islands are relicts of karst limestone mountains that became submerged during the Holocene transgression 7000 - 8000 year ago. The combination of the longtime karst process and recent marine processes in the monsoonal tropical zone has created a very diversity landscape on the Cat Ba Islands that can be divided into 3 habitat types with 16 forms. The first habitat type is the karst mountains and hills, including karst mountains and hills, karst valleys and dolines, karst lakes, karst caves, and old marine terraces. The second habitat type is the limestone island coast, including beaches, mangrove marshes, tidal flats, rocky coasts, marine notch caves, marine karst lakes, and bights. The third habitat type is karst plains submerged by the sea, including karst cones (fengcong) and towers (fengling), bedrock exposed on the seabed, sandy mud seabed, and submerged channels. Like the landscape, the biodiversity is also high in ecosystems composed of scrub cover - bare hills, rainy tropical forests, paddy fields and gardens, swamps, caves, beaches, mangrove forests, tidal flats, rocky coasts, marine krast lakes, coral reefs, hard bottoms, seagrass beds and soft bottoms. The ecosystems on the Cat Ba Islands that support very high species biodiversity include tropical evergreen rainforests, soft bottoms; coral reefs, mangrove forests, and marine karst lakes. A total of 2,380 species have been recorded in the Cat Ba Islands, included 741 species of terrestrial plants; 282 species of terrestrial animals; 30 species of mangrove plants; 287 species of phytoplankton; 79 species of seaweed; 79 species of zooplankton; 196 species of marine fishes; 154 species of corals; and 538 species of zoobenthos. Many of these species are listed in the Red Book of Vietnam as endangered species, included the white-headed or Cat Ba langur (Trachypithecus poliocephalus), a famous endemic species. Human activities have resulted in significantly changes to the landscape end ecosytems of the Cat Ba islands; however, many natural aspects of the islandsd have been preserved. For this reason, the Cat Ba Islands were recognized as a Biological Reserved Area by UNESCO in 2004.

Classification and Antioxidant Activities of Mangrove Plants in Weno Island, Micronesia (미크로네시아 웨노섬 서식 망그로브 식물의 분류 및 항산화 활성)

  • Chung, Youngjae;Hwang, Jinik;Suh, Sung-Suk;Park, Mirye;Kim, Donggiun;Park, Jongbum;Lee, Taek-Kyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • 제15권9호
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    • pp.5885-5892
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    • 2014
  • Mangrove plants serve as a sink of heavy metals and contain phenolic compounds at a high level. Therefore, with mangrove plants, recent studies to develop phytoremediation and natural antioxidants have been conducted in the commercial and academic fields. In the present study, six mangroves in Weno Island of Micronesia were investigated for their phylogenetic relationship and antioxidant activities. First, to determine the phylogenetic relationship among them, rbcL (large subunit of ribulose-bisphosphate carboxylase), one of the chloroplast genes, was used as a molecular marker. According to the data, Xylocarpus, Sonneratia and Rhizophora showed close similarity but not Excoecaria. The levels of phenolic compounds in the bark were abundant in R. apiculata and X. granatum, accounting for 1.10 mM/mg, while R. stylosa and S. alba contained the low amounts, representing 0.73 mM/mg and 0.72 mM/mg, respectively (p<0.05). In addition, bark extracts from R. apiculata, X. granatum, X. moluccensis, and E. agallocha had high antioxidant activities through the DPPH radical scavenging activity and ABTS analysis, whereas S. alba showed the lowest activities. These results suggest that the bark of R. apiculata can be used as a good source for the development of natural antioxidants.

Kinetics of di-n-Butyl Phthalate Degradation by a Bacterium Isolated from Mangrove Sediment

  • XU XIANG-RONG;GU JI-DONG;LI HUA-BIN;LI XIAO-YAN
    • Journal of Microbiology and Biotechnology
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    • 제15권5호
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    • pp.946-951
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    • 2005
  • Biodegradation of the endocrine-disrupting chemical di-n-butyl phthalate (DBP) was investigated using a bacterium, Pseudomonas fluorescens B-1, isolated from mangrove sediment. The effects of temperature, pH, salinity, and oxygen availability on DBP degradation were studied. Degradation of DBP was monitored by solid-phase extraction using reversed-phase HPLC and UV detection. The major metabolites of DBP degradation were identified as mono-n-butyl phthalate and phthalic acid by gas chromatography-mass spectrometry (GC-MS) and a pathway of degradation was proposed. Degradation by P. fluorescens B-1 conformed to first-order kinetics. Degradation of DBP was also tested in seawater by inoculating P. fluorescens B-1, and complete degradation of an initial concentration of $100{\mu}g/l$ was achieved in 144 h. These results suggest that DBP is readily degraded by bacteria in natural environments.

Genome Shuffling of Mangrove Endophytic Aspergillus luchuensis MERV10 for Improving the Cholesterol-Lowering Agent Lovastatin under Solid State Fermentation

  • El-Gendy, Mervat Morsy Abbas Ahmed;Al-Zahrani, Hind A.A.;El-Bondkly, Ahmed Mohamed Ahmed
    • Mycobiology
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    • 제44권3호
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    • pp.171-179
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    • 2016
  • In the screening of marine mangrove derived fungi for lovastatin productivity, endophytic Aspergillus luchuensis MERV10 exhibited the highest lovastatin productivity (9.5 mg/gds) in solid state fermentation (SSF) using rice bran. Aspergillus luchuensis MERV10 was used as the parental strain in which to induce genetic variabilities after application of different mixtures as well as doses of mutagens followed by three successive rounds of genome shuffling. Four potent mutants, UN6, UN28, NE11, and NE23, with lovastatin productivity equal to 2.0-, 2.11-, 1.95-, and 2.11-fold higher than the parental strain, respectively, were applied for three rounds of genome shuffling as the initial mutants. Four hereditarily stable recombinants (F3/3, F3/7, F3/9, and F3/13) were obtained with lovastatin productivity equal to 50.8, 57.0, 49.7, and 51.0 mg/gds, respectively. Recombinant strain F3/7 yielded 57.0 mg/gds of lovastatin, which is 6-fold and 2.85-fold higher, respectively, than the initial parental strain and the highest mutants UN28 and NE23. It was therefore selected for the optimization of lovastatin production through improvement of SSF parameters. Lovastatin productivity was increased 32-fold through strain improvement methods, including mutations and three successive rounds of genome shuffling followed by optimizing SSF factors.