Jurnal Ilmu dan Teknologi Kelautan Tropis
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THE EFFECT REPLACEMENT OF OXYGEN ON TRANSPORTATION SEEDS GROUPER WITH CLOSED SYSTEM
No full textThe location of grouper aquaculture are usually far from the seed source so it takes a long time to transport the seeds. The research purposes was to extend the time by replacing oxygen so the seeds can reach the destination that is located far away with high survival and healthy condition. Previously conducted preliminary research that is transportation with a different length of time 24 hours; 36 hours; 48 hours and 60 hours. The best results of the preliminary study are 24 hour transport which is then used in the main research. In the main study, fish seeds were transported for 24 hours later, oxygen was replaced by: oxygen in disposable plastic bags replaced with new oxygen. Then repackaged to continue transport up to 12 hours; 24 hours; 36 hours and 48 hours. Trasportation conducted with closed system with car. Seeds used were cantik grouper hybrid seed i.e., a crossbreed between female tiger grouper (Epinephelus fuscoguttatus) and male marbled grouper (Epinephelus microdon), a size of 7.0 ± 0.54 cm, with a density of 125 fish / boxes. Grouper seeds were packed with 0.8 mm thick plastic bags, 120cm x 53cm wide, filled with 10 liters of sea water, oxygen is added with a volume ratio of water: oxygen is 1: 3, then put in 75 x 40 x 30 cm styrofoam box. The best result is after fish is transported 24 hours, then replaced oxygen and transported again for 24 hours, so that transportation time can be extended up to 48 hours, with survival rate 98.4%. Keywords: grouper seeds, oxygen replacement, transportatio
RESPONSE OF SEA SURFACE TEMPERATURE (SST) AND CHLOROPHYLL-A ON MADDEN JULIAN OSCILLATION (MJO) IN INDONESIAN SEAS
Get PDFMadden-Julian Oscillation (MJO) is a large-scale phenomenon that occurs in equatorial area, parti-cularly Indonesia. This research aimed to investigate the MJO propagation process and studied the correlation between MJO and sea surface temperature (SST) and chlorophyll-a. Sea variables (SST and chlorophyll-a) and atmosphere variables (outgoing longwave radiation/OLR, 1,5 km wind, and surface wind) were band-pass filtered for 20-100 days period. Spectral density from OLR and 1,5 km wind (2003-2012) shows that the MJO period was dominantly occurred for 40–50 days. Average pro-pagation of MJO velocity resulted from the atmospheric variable analysis by Hovmöller diagram was 4,7 m/s. Cross correlation between SST and OLR in South Java and Banda Sea results a strong corre-lation during MJO active phase, where MJO took place first and was then followed by the decreasing SST along the equatorial region. Increasing chlorophyll-a concentration occured at some areas du-ring MJO active phase with relatively short phase delay. During the MJO active phase, fluctuation of wind velocity generates variation over mixed layer depth and triggers upwelling /entrainment. Nutri-ent was upwelled to the water surface and hence increase phytoplankton production and chlorophyll-a concentration. Keywords: Madden Julian Oscillation, OLR, sea surface temperature, surface chlorophyll-
DISTRIBUTION AND BEHAVIOUR OF DISSOLVED AND PARTICULATE Pb AND Zn IN JENEBERANG ESTUARY, MAKASSAR
Get PDFABSTRACTDissolved and particulate heavy metals play a role in geochemical cycle as an agent in adsorption-desorption, deposition-resuspension, and dispersion mechanisms of heavy metals in water environment. The objectives of this research were to determine the distribution and behaviour of dissolved and particulate heavy metals Pb and Zn in different seasons (west and east seasons) at Jeneberang Estuary of Makassar. Concentrations of Pb and Zn were analysed using Atomic Adsorption Spectrophotometry based on APHA, AWWA, WEF (2005). The concentration of dissolved Pb in the riverine, estuarine, and marine waters were in the range (average) of <0.002 mg/L (below detectable limit), 0.013-0.144 mg/L (0.047 mg/L), 0.016-0.198 mg/L (0.079 mg/L); and the concen-tration of dissolved Zn were in the range (average) of <0.002 mg/L (below detectable limit), <0.002-0.014 mg/L (0.005 mg/L), <0.002-0.083 mg/L (0.017 mg/L). Meanwhile, the concentration of parti-culate Pb were in the range (average) of 1.807-2.569 mg kg-1 (2.215 mg kg-1), 0.521-1.272 mg kg-1 (0.911 mg kg-1), 0.465-2.182 mg kg-1 (1.033 mg kg-1), and the concentration of particulate Zn were in the range (average) of 19.151-90.942 mg kg-1 (51.710 mg kg-1), 16.999-63.059 mg kg-1 (31.694 mg kg-1), 19.439-80.283 mg kg-1 (45.554 mg kg-1) in the riverine, estuarine and marine waters, respecti-vely. Behaviour of dissolved heavy metals Pb and Zn showed that the concentrations tended to increase (desorption) along the gradient of high salinity as a result of the higher heavy metals input from coastal region than that riverine regimes.Keywords: distribution, behaviour, dissolved, particulate, heavy metal, Jeneberang Estuar
POTENTIAL USE OF Ulva lactuca AS FEED INGREDIENT FOR TILAPIA
Get PDFDue to the mainly imported for fish feed ingredients in Indonesia, many attemps have been made to discover local potential ingredients to reduce the utilization of imported ingredients. In this experiment, the utilization of Ulva lactuca as feed ingredient for tilapia was evaluated. Experiment 1 was conducted to determine the digestibility of Ulva for tilapia. In experiment 2 and 3, Ulva was used to substitute wheat pollard of either 0, 3, 6, 9, or 12 % in the feed formulation. In experiment 2, fish with an average body weight of 4.1±0.15 g were fed on those diets, and were cultured for 55 days. To calculate the digestibity in experiment 3, Cr2O3 was added into the diet of exeriment 2; then fed on the fish with an average body weight of 19.0±0.67 g. Results showed that apparent digestibility of dry matter and crude protein of Ulva were 66.3 and 83 %, respectively. Ash content in the diet increased of 13.5% with Ulva inclusion of 12%. On the other hand, using Ulva as a substitute for pollard up to 12% was not affected the growth performance of fish. Regardless of the Ulva level in the diet, the digestibility of the diet was the same. Therefore, Ulva is a potential source of local feed ingredient for tilapia. Keywords: Ulva lactuca, tilapia, digestibility, growt
VARIABILITY OF CARAPACE WIDTH SIZE AND ABUNDANCE OF BLUE SWIMMING CRABS (Portunus pelagicus Linnaeus) IN PATI WATERS
Get PDFFishing effort enhancement would put pressure on blue swimming crab resources and its ecosystem. The objective of this study was to determine the spatial distribution based on the size of the carapace width (CW), abundance, temperature, salinity, depth, and fishing intensity in Pati waters which was divided into two zones (zones 1=nearshore, zone 2=offshore). The result showed that the average of carapace width in zone 1 to zone 2 was significantly different (p <0.05), as well as between males and females. Average number of individual (abundance) was significantly different according to fishing areas and sex (p <0.05). The average of water temperature in zone 1 was higher than in zone 2, salinity in zone 1 was smaller than in zone 2, and the water depth in zone 1 was shallower than in zone 2. The higher the crab catch intensity leaded to the smaller the abundance and size of carapace width. Alternative management strategies were proposed such as to divert fishing grounds from coastal waters to offshore during low productivity season, to uphold rules on minimum legal size for catching (Lm = 107 mm), to release of berried females catch, and to reduce accretion rate of gear and fishing fleet mainly in the coastal zone waters.Keywords: blue swimming crab, carapace widht (CW), abundance, intensity of fishin
LEVEL OF CRABLET PRODUCTION IN MANGROVE CRAB Scylla paramamosain WITH FEEDING ENRICHMENT USING HUFA AND VITAMIN C ON LARVAE STAGES
Get PDFThe objective of the research was to determine the best enrichment of rotifer and the naupli of Artemia as feed for mud crab, S. paramamosain larvae, also to know their increasing of the DHA/EPA ratio and vitamin C content. Four treatments were tested, namely : A) Mud crab larvae every two days were given rotifer and naupli of Artemia enriched with HUFA and vitamin C also added RICA-1 probiotic at 2 mg/L, B) Mud crab larvae every two days were given rotifer and naupli of Artemia enriched with HUFA and vitamin C, C). Mud crab larvae every two days were given rotifer and naupli of Artemia enriched with vitamin C, and D). Mud crab larvae every three days were given rotifer and naupli of Artemia enriched with vitamin C. Result showed that the crablet production from the highest to the lowest was as follows: treatment A (177.5+17.6 ind./tank), treatment B (160+14.1 ind./tank) (A and B showed no significant different results (P>0.05)), treatment C (136+5.6 ind./tank), and treatment D (106+8,5 ind./tank) (C and D results indicated a significantly different (P<0.05) with treatment A). Higher level of DHA/EPA ratio of 69.23% was found on rotifer enriched with HUFA, while on naupliofArtemia only 28,72%. Higher level content of vitamin C was 50.56% in rotifer enriched with vitamin C, while in naupli of Artemia was only increase to 35.56%.Keywords: Scylla paramamosain larvae, enrichment, HUFA, vitamin C, crable
THE ABUNDANCE OF ORNAMENTAL CORALS AFTER MASS DIE OFF IN 1997 ON THE PADANG SHELF REEF SYSTEM, WEST SUMATERA, INDONESIA
Get PDFABSTRACTThe Indonesian Ministry of Marine Affairs and Fisheries aims to establish export quota ornamental corals based on scientifically-founded data from the natural environment. The purpose of this study was to determine the abundance of ornamental coral after mass die off in 1997. Ornamental corals were classified into three groups based on the guideline of ornamental coral propagation for trading purposes. Classification categories are rapid (3-6 months), middle (8-12 months), and slow growth rate (>24 months), which relates to their harvesting time when transplanted for the trade purpose. The survey method used line intercept transects to get coral condition data and belt transect with 2 m width to get ornamental coral data. Both line and belt transect have 30 m length and with three replicates. The study showed number of colony and abundance of ornamental coral for fast growth rate group such as Acropora sp (1348 col & 7.49 col/m2), Galaxea sp, Hydnophora exesa, H. microconus, Pocillopora damicornis, Stylopora sp and Montipora sp with the highest abundant found on Acropora sp and Montipora sp (1348 col & 7.49 col/m2). Whereas the coral which from middle growth rate were Leptoseris sp, Pavona sp, Platygyra sp, Favia sp, Favites sp with the highest abundant found on Favia sp (101 col & 0.56 col/m2). Coral species typically used for ornamental coral trade within the slow growth rate category such massive coral were not found on this survey. Due to the massive coral die-off in 1997 and the paucity of ornamental corals, the utilization of ornamental coral should be supported by coral transplantation and the broodstock of slow growth of coral taken from other area. Keywords: ornamental coral, abundant, mass die off, Padang Water
DISTRIBUTION OF SEAGRASSES IN INNER AMBON BAY
Get PDFABSTRACTExcessive sedimentation in Inner Ambon Bay (IAB) is alleged to cause the degradation of seagrass ve-getation in the area. To get a clearer picture about the matter, we conducted a field study in October 2010 - January 2011 to describe the distribution and density of seagrass at several locations in IAB with different conditions of sedimentation levels. Data were collected using transects perpendicular to the coastline along the seagrass vegetation. The results showed that there were six species of seagrass which were spreaded unevenly. At the locations with high sedimentation, we found the formation of monospecies seagrass vegetation. Conversely, at the locations with low sedimentation, we found the formation of multispecies seagrass vegetation. The distribution and abundance of each species was related to the differences of seagrasses ability to grow in a certain environment and the compe-titiveness among them. Keywords: sedimentation, distribution, seagrass, Inner Ambon Ba
MORPHOLOGICAL CHARACTER AND MOLECULAR IDENTIFICATION WITH COI GENE MARKER OF HORSESHOE CRABS (Tachypleus gigas) AT COASTAL WATERS OF NORTHERN JAVA ISLAND
Get PDFThe existence of horseshoe crabs Tachypleus gigas is currently on the threatened condition and its population status is also unclear. The objectives of this research were to asses the horseshoe crabs morphological characters and to identify based on molecular marker of Cytochrome Oxydase Subunit I (COI) gene. The samples were collected from five locations (Segara Menyan Subang, Ujung Kulon Banten, Tambak Lorok Semarang, Betah Walang Demak, and Kenjeran Surabaya) in October 2014 until June 2015. A total of 27 parameters for 62 individuals were used to determine connectivity and character identifier among populations. Data were tested using non-parametric analysis. While, the 5 individuals from each sites were used for molecular analysis including several stages of the DNA extraction, DNA electrophoresis, amplification and visualization of DNA fragments, and DNA sequencing. The results obtained based on morphological characters that T. gigas of Surabaya formed a unique group due to its body size (X1-X2 and X4-X16) was larger than the other 5 body parts (X22, X23, X26-X28) of Semarang, Demak, Subang, and Banten. According to molecular results, there were 650 bp conserve nucleotide sequences. Analysis using software MEGA 5.0 showed that there were 73 existence of specific nucleotide sites that can be used to distinguishes between T. gigas in-groups and out-groups (T. gigas from Central Arabian Sea, T. tridentatus from Sweden, and Carcinoscorpius rotundicauda from USA).Keywords: horseshoe crabs, Java coast, morphology, identification molecular, CO1 gene
SPATIAL AND TEMPORAL VARIABILITY OF FISH COMMUNITY BIOMASS IN COASTAL WATERS OF TANGERANG REGENCY, BANTEN
Get PDFCoastal waters of Tangerang Regency has abundant in fish resource including pelagic, demersal, and reef fish. This study was conducted to assess fish biomass variability and of fish community structure in coastal waters of Tangerang Regency which can be used as a basis in determining alternatives for sustainable fish resource management. This research was conducted in June and August 2013 in three locations i.e., Kronjo, Cituis, and Tanjung Pasir. Primary data collected were fish weight per species. Fish biomass from each locations was obtained using swept area method using trawl. The results showed that Kronjo region contained the highest total average biomass of fish. Temporally, total ave-rage biomass of fish in August was higher than in June for Kronjo and Cituis. Meanwhile, the con-trary occurred in Tanjung Pasir. This conditions occurred due to the high current and high wave in August than in June. In general, biomass of planktivorous was dominant during the study indicating overfishing lead to fishing down the food web in the Coastal waters of Tangerang Regency. Keywords: biomass, coastal waters of Tangerang Regency, spatial and temporal variability, swept area, over fishing