Jurnal Ilmu dan Teknologi Kelautan Tropis
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    MEIOFAUNA (FORAMINIFERA) IN SEDIMENTS AND ITS RELATION TO WHITE SANDY BEACH OF SENGGIGI AND WATER CONDITION OFF WEST LOMBOK

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    A development of meiofaunal data (foraminifera) from offshore area of West Lombok was conducted on 20 marine sediment samples. The samples were taken out using a grab sampler in 1997. The purpose of this study was to apply the formula of Foraminiferal Index by Hallock et al. (2003). Another purpose of this study was to recognize its relation of white sands of Senggigi beach that was dominated by Shlumbergerella floresiana. The result of analysis showed that the value of Foraminiferal Index (FI) was varies between 1.22 and 9.81. The low value of FI (<2) was found at sites that were close to the coastal area. The values FI >2 and <4 occur at five stations that gave indication of limited environment for coral growth. Value of FI >4 that showed good water condition was found in an area surrounding small islands of Gili Trawangan, Gili Meno, Gili Air and southern part of the study area. Based on the identification of foraminiferal specimens, the occurrence of Shlumbergerella floresiana was not abundant as it was accumulated in Senggigi beach. This result showed that this species did not come from samples studied but might come from marine sediment adjacent to the Senggigi beachKeywords: Benthic foraminifera, FORAM Index, west Lombo

    OPTIMALIZATION OF FEED DOSAGE AND FREQUENCY IN PRODUCTION OF ROTIFER (Brachionus rotundiformis)

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    The availability of rotifer as live food is importance in a larval mariculture. Therefore a continuous and high production of rotifer is needed. The study was aimed to determine the frequency and dosage of the best food in rotifer culture. Nannochloropsis oculata, yeast and scott’s emulsion are used as potential feeds for rotifer. Three dosages of N. oculata (150,000; 250,000, and 350,000 cells/ind.rotifer/day) were applied in the study and were given twice per day. Meanwhile, yeast(0.5 g/106 ind./day) and Scott’s emulsion with different dosages (2, 4, and 8 μg/106 ind./day) were given with two different feeding frequencies (two and four times a day) for each dosages. Each treatment was done in triplicates. Sampling of rotifer was conducted in the morning (AM) and afternoon (PM). Water quality (temperature, dissolved oxygen and ammonia) was also measured. Growth and productivity of rotifer were determined from the number of rotifer and the number of rotifer eggs, respectively. The results showed that the optimum productivity of rotifer was achieved by giving N. occulata of 250,000 sel/ind/day, twice a day in four days culture. Meanwhile, treatment with yeast and Scott’s emulsion gave best performance when applying 0.5 g/106 and 2 μg/106 ind./day twice per day, respectively. Yeast and scott’s emulsion treatment yielded optimum production in two days of culture.Keywords: rotifer, productivity, yeast, Scott’s emulsion, foodd dosag

    ECOTOURISM DEVELOPMENT IN TANJUNG BALAI DISTRICT, NORTH SUMATERA: MANGROVE FOREST ECOLOGICAL FACTORS

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    District of Tanjungbalai characterized by mangrove ecosystem with mud and sandy beaches has the potential to be developed for marine ecotourism. One way to maintain the existence of mangrove forests from destruction or extinction is to develop the Tanjungbalai district to be an ecotourism area. The research objective was to determine the potential ecological mangrove forest to be developed as an ecotourism area. The study was conducted in August-November 2011, using survey methods. Primary data were obtained through direct observation in the village of Bagan Asahan, Asahan Mati and Sungai Apung on mangrove community structure (density value) and ecological potential. Data analyses for suitability tourism index were based on Yulianda (2007). The results showed that the mangrove forest in the Tanjungbalai District had a good density in the category of very dense (the value of 1778 ind./Ha), mainly consisting of Bruguiera gymnorrhiza, Xylocarpus granatum, Rhizophora mucronata and Rhizophora apiculata. Suitability tourism index in the Tanjungbalai District was very suitable (S1) for mangrove tourism development including Village of Bagan Asahan (score 65, IKW 85.53%), Asahan Mati (score 61, IKW 80.26%) and Asahan Apung (score of 61, IKW 80.26%). Ecologically, mangrove forests in the district of Tanjungbalai is potential to serve as a mangrove ecotourism area. Keywords: mangrove forest, potential ecological, ecotourism developmen

    SPAWNING AND LARVAL DEVELOPMENT DOG CONCH (Strombus turturella)

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    Dog conch (Strombus turturella) is considered one of fishery commodities in Bangka Belitung Islands. This conch is often exploited and result in their populations are increasingly threatened. The aim of study to observe the reproduction and larval development of dog conch were studied under laboratory conditions. For the treatment of spawning the dog conch were placed in spawning tanks with a capacity of 1 ton. Stimulation of spawning is done by replacing the water in the tank as much as 90% every 24 hours until the eggs released by females. Spawning was preceded by copulation and fertilization occurs inside the female\u27s body.The results showed that the first egg cell divides into two cells after two hours of spawning. Then each cell continues to divide into four cells to become multicellular and reach the gastrula stage after 48 hours. Free swimming larval phase for four days and then settle down along with the formation of the first shell. The larvae will grow up to 5 mm shell length for 20 days.Keywords: Dog conch, Strombus turturella, spawning, larva developmen

    IDENTIFICATION OF SECONDARY METABOLITES COMPOUNDS, ANTIBACTERIAL AND ANTIOXIDANT ACTIVITIES ON THE METHANOL EXTRACT OF SEA CUCUMBER Stichopus hermanii

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    Identification of secondary metabolites, antibacterial and antioxidant activities assay of methanol extract of sea cucumber Stichopus hermanii were conducted from May to July 2011 at the Natural Products Laboratory, Research Center for Oceanography, Indonesian Institute of Sciences. Sea cucumber used in this study comes from South Lampung waters. Objective of the study was to get information of secondary metabolites, antibacterial and antioxidant activities of methanol extract of sea cucumber S. hermanii. The extraction method which used in this experiment was the maceration method using methanol solvent. Identification of secondary metabolites was performed through observing reaction of colors, precipitation, and foaming. Antibacterial and antioxidant activities of methanol extract from sea cucumber were tested using agar diffusion method and reducing of free radicals 1.1-Diphenyl-2-Picrylhydrazyl (DPPH) respectively. The results showed that secondary metabolites identified in the methanol extract of sea cucumber S. hermanii were saponin and steroids. Both secondary metabolites had antibacterial activities against Staphylococcus aureus, Vibrio eltor and Bacilus subtilis. The analysis of antioxidant activity showed that the IC50 value of methanol extract of sea cucumber S. hermanii was about 65.08 ppm. It indicated that S. hermanii is having potency as antibacterial and antioxidant. Keywords: antibacterial, antioxidants, sea cucumber Stichopus hermanii, secondary metabolite

    VARIABILITY OF CHLOROPHYLL-A CONCENTRATION AND SEA SURFACE TEMPERATURE OF NATUNA WATERS

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    Variability of chlorophyll-a concentration and sea surface temperature (SST) in Natuna waters were analyzed using satellite data Sea-viewing Wide Field-of-view Sensor (SeaWiFS) and the National Oceanic and Atmospheric Administration-Advanced Very High Resolution Radiometer (NOAA-AVHRR). SeaWiFS data with a resolution of 9×9 km2 and AVHRR with a resolution of 4×4 km2 were the monthly average data downloaded from NASA website. Chlorophyll-a concentrations and SST were estimated using OC4v4 and MCSST algorithms. In general, the concentration of chlorophyll-a in Natuna waters ranged between 0.11-4.92 mg/m3 with an average of 0.56 mg/m3 during the west season and 0.09-2.93 mg/m3 with an average of 0.66 mg/m3 during the east season. Chlorophyll-a concentrations were relatively high seen in coastal areas, especially around the mouth of the Kapuas, Musi, and Batang Hari rivers allegedly caused by the high nutrient intake from the mainland. SST variability in Natuna waters ranged from 23.46-30.88 °C during the west season and tended to be lower than that the east season (27.91-31.95 °C). In addition, the SST values tended to be lower in the offshore than that inshore. During the west season (Nov-Feb) and the transitional season (Apr) in the years of Elnino Southern Oscillation (ENSO), the concentration of chlorophyll-a and the SST in Natuna waters was generally higher than that in non-ENSO years. The results of wind analyses showed that ENSO caused the change of direction and speed of wind from its normal conditions.Keywords: Sea surface temperature, chlorophyll-a, Natuna waters, ENSO, SeaWiFS, AVHR

    MICROALGAE FOR CO2 REDUCTION AND WASTEWATER TREATMENT APPLICATION IN INDUSTRIAL AREA

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    The microalgae incorporated photobioreactor (PBR) is a highly efficient biological system for converting carbon dioxide (CO2) gases into biomass and treating wastewater. In this study, the freshwater microalgae Chlorella sp. was cultured in two unit photobioreactors which were connected to a boiler of dairy factory. The source of water for microalgae culture media (in the photobioreactors) are collected from the waste water treatment plant of the dairy factory itself. The objective of this microalgae photobioreactor activity were to reduce CO2, produce biomass and as a part of a waste water treatment in a dairy industry in Indonesia. Both photobioreactors were operated for 14 days culture interval in the semi continuous cultivation, with initial stocking rate of 2 x 105 cells/ml microalgae. Carbon dioxide concentration from the boiler stack was 10-11 % vol. The photobioreactors were injected with the specified CO2 concentration with flow rate of 2 l/min. and 1.5 l/min. The result showed that microalgae photobioreactors capability in CO2 absorption were 0.78 ± 0.25 and 0.92 ±0.36 g CO2/l media/day, respectively. Before and after utilized by the photobioreactors system, Nitrate and Phosphate concentration of the culture media (supplied from the waste water treatment plant) decreased from 3-4 mg/l to 0.05-0.1 mg/l. After 14 days cultivation, biomass concentration of microalgae which were injected with CO2 flow rate of 2 l/min. and 1.5 l/min. were 19 x 106 cells/ml and 15 x 106 cells/ml respectively. Results showed that microalgal photobioreactors operated in an industrial area could reduce CO2 concentration and produce biomass.Keywords: photobioreactor (PBR), Chlorella sp., CO2 flue gas emissions, wastewate

    INCREASE OF THE THERMOCLINE LAYER DUE TO TSUNAMI 2004 IN NANGRO ACEH DARUSSALAM WATERS

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    Research of physical oceanographic conditions post-tsunami was carried out and subsequently compared with the pre-tsunami 1998. Measurement of suhu, salinity and light transmission was conducted by CTDSBE911pls Model. Results showed that the flow in the Straits of Malacca flowed into the northwest and turned back into the Strait of Bengal and the next rotation into the flow of waters along the west coast of Nangro Aceh Darusalam (NAD). The mainstream off coast NAD in the Indian Ocean flowed to the northwest. Upper thermocline layer (17 m to 50 m) moved upward in 2005 and 2006 compared with previous data 1998 (90 m to 125 m). The moving upward thermocline in 2006 was allegedly due to the influence of Indian Ocean Dipole (IOD) positive. This requires further verification through long-term data collection to determine the monthly and annual variations, which will be compared with previous research. Light transmission (Tx) in 2005 from the surface to near the bottom (water column) was found lower than the year 1998 and 2006. This result was allegedly caused by resuspension from the seabed by energy turbulent produced by the tsunami. Heat content between 5 to 65 m depth in 2005 was higher than in 1998 and 2006. The higher heat content during the year of 2005 (post tsunami) was caused by friction due to the influence of tsunami energy, which predominantly found in the mixed layer depth. Type of water masses in the study area was a mixing between the local water mass, Malacca Strait Water (MSA), Bay of Bengal Water (BBW) under the influence of Arab Waters (AW), and the Indian Deep Water (IDW).Keywords: current, thermocline, heat content, watermass type, and Nangro Aceh Darusala

    THE STUDY OF FERTILITY MARINE ECOSYSTEM OF SOUTHEAST SULAWESI BASED ON BACTERIOLOGICAL ASPECT

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    The study of waters fertilization in Southeast Sulawesi include Flores Sea, Kabaena Strait, Muna Strait, Buton Strait and Tioro Strait based on bacteriological aspect was conducted on April–May 2006, using the Research Vessel Baruna Jaya VII with total stations 25. The aim of investigation was to find out the total numbers and pattern of distribution heterotrophic bacteria and productivity bacteria in the marine ecosystem of Southeast Sulawesi and related with waters fertilization. The analysis of heterotrophic bacteria was determined based on the Total Plate Count method, whereas bacterial productivity with Acridine Orange Direct Count method. The result indicated that the pattern of distribution and total numbers of heterotrophic bacteria at the surface layers varied between (10–10220)CFU x 10-1/ml with an average 940CFU x 10-1/ml. While at the bottom layer varied between (2–488)CFU x 10-1/ml with an average 91CFU x 10-1/ml. For the bacterial productivity in the form of Carbon biomass at the surface layers varied between (1.30– 5.84) x 10–7grC/m3 with an average 3.56 x 10–7grC/m3, at the bottom layer varied between (0.24–1.33) x 10–7grC/m3 with an average 0.64 x 10–7grC/m3. The result of numbers bacteria that in Southeast Sulawesi waters was lower than the Arafura Sea but still higher than the Aceh Sea. The fluctuation of numbers bacteria perhaps due to the factor of monsoon and environmental was influenced on the marine ecosystem. In general this paper conclude that the condition of marine ecosystem Southeast Sulawesi still relatively fertility.Keywords: Fertility, heterotrophic bacteria, productivity bacteria, Southeast Sulawesi water

    SEA LEVEL VARIATION AND GEOSTROPHIC CURRENT OF THE SUNDA STRAIT BASED ON TIDAL AND WIND DATA IN YEAR 2008

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    Sea level variation from four tide-gauge data in the Sunda Strait, Indonesia, in the year 2008 has been studied by using Wavelet 1 D Daubechius 1 level 5 type and Fast Fourier Transform methods. The hourly sea level variation in April and November (representing transitional seasonal conditions) is approximately +0.49 m; whereas in January (representing Northwest Monsoon condition) and July (representing Southeast Monsoon condition) can reach up to -0.48 m. In 2008, sea level variation in the Sunda Strait is mainly influenced by the monsoon. Results from this study show that there are at least three phenomena of sea level variations in the Sunda Strait, namely (1) seasonal variation (periodicity between 4-6 months) where it is believed influenced by the Java Sea; (2) intra-seasonal (periodicity between 1-3 months), which is more influenced by the Indian Ocean; and (3) tidal forcing (periodicity between 14-17 days, suggesting fortnightly tidal forces) which propagates from the Indian Ocean into the Sunda Strait. Result from surface geostrophic approximation calculation suggests that during Southeast Monsoon (June-August), monthly mean current flows southwestwardly towards the Indian Ocean with a velocity of 0.14-0.16 m/s. Whereas during Northwest monsoon (December-February), current flows northeastwardly towards the Java Sea with a velocity of 0.14-0.17 m/s. Furthermore, on the daily time scale, tidal current in the Sunda Strait flows into the Java Sea (Indian Ocean) during high tide (low tide) with a velocity ranging from 0.51 to 0.72 m/s (0.48 to 0.51 m/s).Keywords: sea level variation, geostrophic approximation, tides, monsoon, Sunda Strai

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