Jurnal Ilmu dan Teknologi Kelautan Tropis
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CORAL REEF SPATIAL DISTRIBUTION IN WANGI-WANGI ISLAND WATERS, WAKATOBI
Get PDFCoral reefs contribute significant benefits in coastal area in Wangi-wangi Island, Wakatobi in terms of their ecological functions to marine biota and socio-economical services to local coastal communities. Therefore, it is importance to observe coral reef condition and its spatial distribution around Wangi-wangi island waters, Wakatobi. In this study Point Intercept Transect (PIT) and GIS tools were used to observe and analyze coral reef condition in Wangi-wangi island waters, Wakatobi. The results showed that coral reef condition in Wangi-wangi island waters can be categorized into moderate and good conditions with coverage percentage ranging from 28 – 60%. Based on spatial analysis non-acropora coral was found in greater cover percentages in Waha village, Sombu village, and Kapota island than other locations. Soft coral cover percentage was also found in larger cover percentage in Waha and Sombu regions than other locations. Keywords: coral reefs, geographic information system (GIS), Wangi-wangi Islan
COMMUNITY STRUCTURE OF SEAWEED AT COASTAL AREA OF HARUKU ISLAND, CENTRAL MOLLUCAS PROVINCE
Get PDFThe study of seaweed biodiversity was conducted in Ory, Pelaw, Kailolo, and Waimital coatal waters of Haruku island in 2011. The purposes or this study were to determine the density and biodiversity of makroalgae in the coastal waters of the Haruku island. Data collection were conducted in June-September 2011 with square transect line method. The results showed that in the coastal area of Kailolo exhibited the highest value in density and biodiversity of macroalgae in the study regions with 47 species from 31 genera consisting of 21 species of red algae, 14 species of green algae and 13 species of brown algae. Gracilaria, Acanthophora, Sargassum, Turbinaria, Caulerpa, and Halimeda were the most dominance in the region. The highest biomass of macroalga found in the Kailolo coastal waters was due to its relatively good habitat contidion consisting of dead coral rubble, sand, coral live with seagrass vegetation dominated by Thalasia hemprizii and Halodule uninervis. Meanwhile, habitat condition at the other locations had suffered a severe damage and dominated by dead coral. Environmental conditions in the study region were within the limits of decent support for the growth of macro algae. Keywords: Macroalgae, diversity, biodiversity, substrat, Haruku islan
SURVIVAL AND RESPONSE MOLTING OF MUD CRAB (Scylla olivacea) INJECTED WITH MURBEY (Morus spp.) LEAVE EXTRACT
Get PDFThe soft shell crab productivity has been hampered due to the long rearing time and unsimultaneous molting of the crab. This study aimed to determine the effect of murbey (Morus spp.) leave extract as molting stimulant on Scylla olivacea and its best extract dosage to be applied in soft shell crabs production technology. Application of murbey extract was conducted by using injection method with 5 treatments such as (a) 0 ppm (as control); (b) 100 ppm; (c) 125 ppm; and (d) 150 ppm for 12 individual per treatment. The results showed that the highest molting percentage (50%) was obtained at the concentration of 100 ppm. Meanwhile, the control (0 ppm), 125 ppm, and 150 ppm treatments displayed the same molting response (33.3%). The fastest latent molting time (29 days) was found at the treatment of 125 ppm and the slowest one of 44 days at 100 and 150 ppm treatments. The best growth of crabs injected with murbey leaves extract was at the concentration of 100 ppm with the carapace width of 6.0 mm and the body weight of 32.98 g, while the lowest was obtained at the concentration of 150 ppm with the carapace width of 3.8 mm and the body weight of 25.43 g. Crabs treated with murbey extract at the concentrations of 100, 125, and 150 ppm exhibited survival rate of 91.7 % vs. the control of 83.3%. Murbey leaves extract have been proven to be effective in stimulating molting mud crab (Scylla olivacea). The 100 ppm exhibited the best response for growth and molting percentage, while the 125 ppm showed the best performance for latent period molting of the crab. Keywords: molting response, survival rate, Scylla olivacea, murbei leaves, Morus spp
SEDIMENTATION RATE AND DISPERSION OF ORGANIC WASTE FROM LOBSTER CULTURE ON CAGE IN EKAS BAY, WEST NUSA TENGGARA PROVINCE
Get PDFThe objective of this study was to determine sedimentation rate and dispersion of organic waste from lobster culture on cage in Ekas Bay, West Nusa Tenggara Province. Measurement of sedimentation rate was conducted every month during the process of cultivation lobster. This measurement was done by setting up a sediment trap under and around the cage. The result of this study showed that sedimentation rate under the lobster cage within 270 days ranged from 14.92 to 27.33 (20.66±4.60) g/m2/day. The organic waste did not disperse far away from the cage because of the small current rate around the cage location of 0.068 to 0.2 m/s. Feces and residual feed settling velocities followed the current direction within the range of 0.0373 to 0.072 m/s with 8.50 m of water depth. According to this result, dispersion of feces particle and residual food was between 8.24 and 45.58 m from the cage. In order to prevent an accumulation of waste particle on the water bottom, the distance between cages needs to be set to at least twice of the farthest distance of particle dispersion which is 2 x 45.58 = 91.16 m or about 100 m. Keywords: sedimentation rate, waste dispersion, lobster culture, Ekas Ba
NATURAL FEED (ROTIFER) MANAGEMENT ON ORANGE SPOTTED GROUPER Epinephelus coioides LARVAL REARING
Get PDFABSTRACT According to Indonesian Standard Quality, the optimal seed production of orange spotted grouper (Epinephelus coioides) has been unsuccessful due to the problems occurred during larval rearing period. Efforts on mass rearing of larvae has been carried out in this study to optimize the natural feeding (rotifer). The purpose of this research was to obtain the information about an appropriate duration time for natural feeding (rotifer) to produce higher survival rate. The treatment for providing rotifers on larvae (days after hatching/DAH) i.e., (A) 20 days, (B) 25 days, (C) 30 days, and (D) 35 days. Rotifers were enriched with DHA Selco. Experiment used fiber tanks with 1 m3 capacity with a completely randomized design (CRD) and three replicates. The larvae was reared to achieve the juvenile phase (D-45). The best results from 1 m3 tanks were then reared using concrete tanks of 6 m3 and 10 m3 capacities. The results showed that feeding of rotifers up to 25 DAH larvae on fiber tanks (1 m3) produced the hughest survival rate (7.63 %). Meanwhile, the mass reared in 6 m3 and 10 m3 concrete tanks produced survival rate of 4.9±3,54% and 8.8±2.26%, respectively. The homogenous size was relatively high (80%) and the seed abnormality was relatively low (0.4%). Keywords: rotifers, feeding time, Orange Spotted grouper larvae, Epinephelus coioide
CHANGE DETECTION OF CORAL REEF HABITAT USING LANDSAT IMAGERY IN MOROTAI ISLAND NORTH MALUKU PROVINCE
Get PDFABSTRACT Scientific information on coral reef habitat changes of Morotai island is very limited to none. This study aimed to detect the change of coral reef habitats between 1996 and 2013, using Landsat imagery integrated with field data in 2012. The research was conducted in the coral reef ecosystem of Morotai Island in North Maluku province. Change detection analyses were conducted using supervised classifications and transformation depth invariant index (DII), with five habitat classes i.e., mixed-habitat, coral, seagrass, sand, and rubble. The result showed that in 1996-2002 there was a significant increase in the mix-habitat and rubble classes (11.3% and 32.5%), however, there was a siginifcant decrease in the sand, seagrass, and coral classes of -14.1%, -14.9%, and -16.6%, respectively. In 2002-2013, mixed-habitat, sand, and seagrass classes were increase by 1.1%, 13.3%, and 24.78%, respectively. Meanwhile, coral and rubble classes were decrease by -22.7% and -27.0%, respectively. Within the period of 1996-2013, there was about 43.6% loss of coral reef of Morotai island. This was probably caused by the increase of seas surface temperature nad and the increase of human activities in the region. Keywords: coral reef habitats, Landsat, change detection, Morotai Islan
EXPRESSION PROFILE OF SEX DETERMINATION GENE, BIOREPRODUCTION, PHENOTYPE, AND LOCOMOTORY PERFORMANCES OF OLIVE RIDLEY, Lepidochelys olivacea INDUCED BY DIFFERENT INCUBATION TEMPERATURE
Get PDFSex determination in turtle species is not only based on genotype, but also rely on the incubation temperature. In addition, sexual differentiation takes place during the thermo-sensitive period (TSP). This study was conducted to determine the effects of incubation temperature on sex expression profile of determination gene, bioreproduction, phenotype, and locomotory performances of olive ridley turtle hatchlings. Fertile eggs incubated at two temperatures, namely feminine temperature (30-33°C), and masculine temperature (26-27°C). Value of cycle threshold (CT) measured during TSP, i.e 23-25 embryonic development stage, and after TSP, i.e 26-27 embryonic development stage using real time PCR techniques. Comparison of gene expression at both incubation temperatures were analyzed by ANOVA, and Student’s t test. Hatchling bioreproduction and phenotype measurement consist of the incubation period, embryo growth, morphometrics, and locomotori performances hatchlings were analyzed with regression analysis and Student’s t test. The results showed expression of both aromatase and Rspond 1 genes (which plays a role in ovarian differentiation) after the TSP that incubated at feminine temperature higher and different with masculine temperature. In conjunction with the bioreproduction and phenotype, the incubation period of feminine temperature shorter than that of masculine. Likewise, growth of the embryo of feminine temperature was faster than that of masculine. Incubation at feminine temperature significantly affect to carapace width, length and width of the plastron, long flippers and rear arms, long neck, and the frequency of the swing flippers. Keywords: thermo-sensitive period (TSP), gene expression, phenotype, Lepidochelys olivace
SCREENING ON THE POTENTIAL BIOACTIVE COMPOUNDS OF ANTIBACTERIAL ACTIVITY IN SOFT CORAL COLLECTED FROM SOUTH BANGKA ISLAND WATERS AND LAMPUNG BAY
Get PDFABSTRACT Soft corals contain bioactive compounds that can be used as a marine natural product. The puposes of this study was to determine of the soft corals inhibition potential for antibacterial activity. The methodology in this study included field sampling, extraction (in the solvent of n-hexane, ethyl acetate and methanol), antibacterial bioassay, and briefly describe the type of soft coral that possesed the highest inhibition. In sampling treatment, the biomass among wet samples and dry samples varied. The highest shrinkage due to drying was found in Nephthea, followed by Lobophytum and Sarcophyton, while the lowest was found in the genus of Sinularia. Extracted from 12 samples of soft coral, the lowest extract weight was found in the semi-polar solvent (EtOAc), while the extract weight of n-Hex and MeOH was vary. Inhibition power from all extract samples was found on soft coral extract in the EtOAc and MeOH solvents. The highest value of inhibition power was found in soft coral of Sinularia polydactyla and S. Flexibilis within strong catogery. Keywords: bioactive compounds, Lobophytum, Nephthea, Sarcophyton, Sinularia, soft cora
EMBRYO DEVELOPMENT AND ENDOGENOUS NUTRIENT ABSORBTION OF SEA SILVER POMPANO FISH LARVAE FROM NATURAL SPAWN OF BROODSTSOCK, Trachinotus blocii, (LACEPEDE)
Get PDFSilver pompano is a prospective high value commodity to be developed in mariculture. The aims of this research were to understand the development of embryo and absorption pattern of endogenous nutrient at the time of changing from using endogenous to exogenous nutrient. This research was conducted in Institute for Mariculture Research and Development, Gondol, Singaraja, Bali using fertilized eggs which were stocked in concrete tanks 3 m3, filled with 2 m3 of seawater, in a density of 25 eggs/l. Temperature at the time of hatching was 28-30oC. The observation of embryo development and its morphology was performed after hatching by collecting larvae as many as 10. Parameters measured were total length of larvae (TL), yolk sac volume (VK), oil globule volume (VM) and larvae development. The results showed that embryo of silver pompano had a normal development, consisted of several phases i.e., fertilized egg, cell division, neurola, gastrula, complete embryo and hatching as larvae. Newly hatched larvae had endogenous nutrient as yolk sac and oil globule with volume of 2.27.10-1 mm3 ± 0.06 and 5.57.10-1 mm3 ± 0.02, respectively. Yolk sac was completely absorbed after 35:30 to 46:30 hours and oil globule after 52:30 to 64:30 hours. Initial feeding was given when yolk sac was completely absorbed but before oil globule was completely absorbed. The average total length of larvae was 2.40 ± 0.10 mm. Keywords: embryo, larvae, absorption, yolk sac, silver pampan
DYNAMIC OF SEA LEVEL ANOMALY OF INDONESIAN WATERS
Get PDFA trend in sea level rise as a result of global warming could be a threat to small islands and coastal areas in Indonesia. The objective of this study was to determine the trend and variability of mean sea level anomaly (MSLA) in Indonesian waters during the 20 years of observation. The data used in this study were monthly MSLA data obtained from the AVISO website (ftp://ftp.aviso.oceanobs.com). Supporting data were the Southern Oscillation Index (SOI) (http://www.gom.gov.au/climate/enso), Dipole Indian Mode (DIM) index (http://gcmd.nasa.gov/records/GCMD_Indian_Ocean_Dipole.html), and the Pacific Decadal Oscillation (PDO) index (http://research.jisao.washington.edu/pdo/). Eigth stations of Indonesian waters were selected to study the variability of MSLA. In general, MSLA variabilities of Indonesian waters had a seasonal pattern, positively correlated with the SOI index, and negatively correlated with DIM and PDO indexes. The partial correlation of DIM was more dominant in west of Sumatra (r=-0.52) and south of Java (r=-0.44), PDO was more dominant in the northern waters of Papua (r=-0.37) and Makassar Strait (r=-0.33), and SOI was more dominant in northern Papua (r=0.52) and less toward the west of Indonesian waters. Overall, the MSLA variability of Indonesian waters can be explained by the variabilities of SOI, DIM, and PDO indexes with the lowest value in Natuna waters by 12% (R2=0.12) and the highest value in the northern waters of Papua by 54% (R2=0.54). Interannual variabilities were observed during ENSO events (SOI<-10) along with the maximum value of DIM index resulted in the lowest value of MSLA. Meanwhile, the highest value of MSLA was found during La Nina events (SOI>10) in conjunction with a minimum value of DIM and PDO indexes. The average rate of sea level rise in Indonesian waters was 5.84 mm/yr, almost two times higher than the average rate of global sea level rise (3.2 mm/yr). Keywords: mean sea level, anomaly, SOI, DIM, PDO, interannual, ENS