Jurnal Ilmu dan Teknologi Kelautan Tropis
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SURVIVAL AND SEEDLING GROWTH OF MOON-EYED SNAIL (Turbo chrysostumus L.) ON DIFFERENT TEMPERATURE CONDITIONS
Get PDFTurbo chrysostumus is commonly known by fishermen community as moon-eyed snail and has common names of yellow-mouth turban or gold-mouth turban. These biota live in rocky beach and coral reefs surface filled with alga. They are also easily collected and used for high nutritive food for coastal villagers. The study of survival and growth of turbo youngsters in relation with different temperature is very limited. This study was done in January 5 – May 4, 2015 in the laboratory with the objective of observing the effect of optimum temperature range on their survival and growth. Based on ANOVA statistical analyses, the temperature had significsant effect on the survival of the turbo youngsters (p<0.05). “Honest Significant Difference” test revealed that control temperature (P1), 26±0.5°C (P2), and 28±0.5°C (P3) produced a significantly different effect on the survival compared with that in 30±0.5°C (P4). Higher growth rate was recorded in 26±0.5°C balanced with high food consumability. The relationship analysis of height shell-weight of wet body in all treatments indicated similar pattern of minor allometric (b<3). Keywords: survival, growth, moon-eyed snail (Turbo chrysostumus L.), temperatur
INTRA-SEASONAL VARIABILITY OF NEAR-BOTTOM CURRENT IN THE HALMAHERA SEA
Get PDFThe secondary entry portal of the Indonesian Throughflow (ITF) from the Pacific to Indian Oceans is considered to be via the Halmahera Sea (HS). However, few ITF studies have been done within the passage. This motivated the Internal Tides and Mixing in the Indonesian Througflow (INDOMIX) program to conduct direct measurements of currents and its variability across the eastern path of the ITF. This study focused on the intra-seasonal variability of near-bottom current in HS (129°E, 0°S), its origin and correlation with surface zonal winds and sea surface height over the equatorial Pacific Ocean. The result showed a strong northwestward mean flow with velocity exceeding 40 cm/s, which represented the current-following topography with the northwest orientation. Meridional current component was much stronger than the zonal component. The energy of power spectral density (PSD) of the current peaked on 14-days and 27-days periods. The first period was presumably related to the tidal oscillation, but the latter may be associated with surface winds perturbation. Furthermore, cross-PSD revealed a significant coherency between the observed currents and the surface zonal winds in the central equatorial Pacific zonal winds (180°E-160°W), which corroborates westward propagation of intra-seasonal sea surface height signals along the 5°S with its mean phase speeds of 50 cm/s, depicting the low-latitude westward Rossby waves on intra-seasonal band. Keywords: current, equatorial Pacific Ocean, zonal winds, sea surface height, Halmahera Se
CHARACTERISTICS OF LIPID BIOMARKERS (N-ALKANES, FATTY ACIDS, STEROLS, N-ALKANOLS AND ISOPRENOID) IN ESTUARINE SEDIMENTS OF MUARA ANGKE JAKARTA BAY AND CILINTANG-UJUNG KULON
Get PDFABSTRACT Lipid biomarkers as specific organic compounds can be used to evaluate the possible contribution of organic carbon from different sources or to trace the biological origin of molecules. The purpose of this research was to assess the contribution of sedimentary organic of origin based on the characteristics of lipid biomarkers in the Muara Angke Estuary-Jakarta Bay and Cilintang-Ujung Kulon. Single sediment sample were collected at the 10 cm deep from the top sediment. Those samples were extracted by soxhlet apparatus and fractioned prior to GC-MS analysis. All of those sediment showed different characteristics of biomarker (n-alkanes, fatty acid, sterol,n-alkanols and isoprenoid). They indicated the different of contribution of organic material inputs influenced by the activity of the upland and surrounding the estuary. Keywords: estuary sediment, GC-MS, lipids biomarker
DISSOLVED SILICATE IN COASTAL WATER OF SOUTH SULAWESI
Get PDFABSTRACT Dissolved silicate (DSi) in coastal waters plays a crucial role in phytoplankton growth particularly diatom. This study aimed to determine DSi concentration seasonally in waters of the western coast of South Sulawesi in relation to coastal water quality indicator. Water, chlorophyll-a, and diatom samples were collected from the coastal areas of the Tallo-Makassar, Maros, and Pangkep, in April 2013 (transitional season), June 2013 (dry season), and February 2014 (wet season). Factorial analysis of variance was used to identify significant seasonal and temporal variations, and linear regression was used to test the relationship of chlorophyll-a and diatom abundance to DSi concentrations. The results showed that the DSi concentration was higher in the wet season of 35.2-85.2 µM than in the other seasons (transitional season: 10.8-68.4 µM, dry season: 9.59-24.1 µM). The abundance of diatoms during the transitional season reached ~9.7x107 cell/m3 in the Pangkep river, 2.3x107 cell/m3 in the Tallo river, and 1.3 x 107 cell/m3 in the Maros river. Chaetoceros, Nitzschia, and Rhizosolenia dominated the diatom composition. The mean concentration of chlorophyll-a in the Makassar coastal waters was 4.52±4.66 mg/m3, while in the Maros and Pangkep waters of 1.40±1.06, and 2.72±1.94 mg/m3, respectively. There was no strong linear corelation between DSi and diatom abundances, nor chlorophyll-a. These results suggested that DSi become a non-limiting factor for the diatom growth and potentially reduce the water quality via eutrophication and diatom blooms. Keywords: dissolved silicate, diatom, chlorophyll-a, coastal waters, South Sulawes
MANGROVE COVERAGE CHANGE DETECTION USING LANDSAT IMAGERIES BASED ON HYBRID CLASSIFICATION IN KEMBUNG RIVER, BENGKALIS ISLAND, RIAU PROVINCE
Get PDFABSTRACT The limited scientific information and lack of attention from stakeholders on the status of mangroves in Kembung River functioned as a basis of this study. Four series of Landsat data recorded in 1996, 2002, 2010, and 2013 were used to map mangrove land cover and changes detection. Hybrid classification technique, a combination of the object-based and random forest classifications, were applied in this study. The result showed that based on hybrid classification, mangrove coverage was detected within 82.6-88.4% overall accuracy. Change detection analyses showed that the mangrove area of Kembung River was relatively stable. For nearly two decades, we found mangrove loss about 197.2 ha, gain of 251.1 ha, and unchanged of 2904.9 ha. Changes in mangrove were generally caused by anthropogenic factors such as mangrove replanting, logging, changes over the function of mangroves into the road, embankment, settlement, shrimp farms, and natural growth. Serious attention from various parties are needed to maintain the existence and sustainablility of mangrove ecosystems in Kembung River. Keywords: Mangrove, Sungai Kembung, monitoring, Landsat, hybrid classificatio
MANAGEMENT ON CORAL REEF ECOSYSTEM IN THE SIANTAN TENGAH DISTRICT, ANAMBAS ISLANDS
Get PDFCoral reef ecosystem management in Siantan Tengah District, Anambas Islands need to be improved to obtain the optimal results. Currently, the coral reef ecosystem management is conducted sectorally, therefore, it can cause a damage on coral reef ecosystem. The purposes of this study were to analyze sustainability status of coral reefs managements in the District Central Siantan and to formulate the sustainability of coral reef ecosystem management. Multi Dimensional Scaling (MDS) with Rap-Insus COREMAG approach was used to analyze the sustainability status of coral reef management. The results showed that the sustainability status of coral reef management in Siantan Tengah District was sustainable with multidimensional index of 51.457. Dimensions that need to be improved to achieve the optimal management of coral reef ecosystems in a sustainable manner is social dimension to the value of sustainability by 42.324 and institutional dimensions of 49.85 which is classed as less sustainable. This results of this research are expected to be able to facilitate the stakeholders to arrange the sustainability of coral reef ecosystem management in the Siantan Tengah District. Keywords: coral reef management, sustainability analysis, Siantan Tengah District, Anambas Island, Multi Dimensional Scaling (MDS
GREEN ALGAE Ulva sp. AS RAW MATERIAL FOR BIOGAS PRODUCTION
Get PDFUlva sp. is a non edible seaweed and posses a high growth rate. Therefore, this species is potential to be developed as a raw material for biogas production. One important factor on the biogas production is to determine organic loading rate (OLR). The aim of this study was to determine the potential of Ulva sp. as a raw material for biogas and to find out the optimum loading rate in the process of biogas production. Biogas production was carried out in the digester with a capacity of 22 l that was made of fiber and equipped with a manual stirrer and gas flow meter to measure gas production. Parameters analised were pH, COD, TSS, VSS, and gas composition. Organic loading rates used in this study were 0.5, 1, 1.5, and 2 kg COD.m-3.day-1. The results showed that the optimum loading rate was 1.5 kg COD.m-3.day-1. In the loading rate of 1.5 kg COD.m-3.day-1, we obtained the highest biogas production rate of 12.14 l/day with methane content of 42.96%, average COD removal of 51.97%, and methane production of 0.33 l/g COD. Keywords: anaerobic, biogas, COD, loading, methane, Ulva sp
ABUNDANCE OF Acanthaster planci AS HEALTH OF CORAL INDICATOR IN TUNDA ISLAND, SERANG REGENCY, BANTEN
Get PDFThe abundance of Acanthaster planci can be used as a health indicator of coral reef ecosystem. A high abundance of A. planci become phatogen on coral and an indication of unhealthy coral reef ecosystem. The objective of this study was to evaluate health of coral reef ecosystem based on the abundance of A. planci and the percent coral cover at Tunda Island, Banten. Field observation conducted in January 2014. The stations were selected by purposive sampling method and based on four-wind direction i.e., north, south, east, and west. Reef data was measured using Line Intercept Transect (LIT), while sampling method for A. planci using Belt Transect. Results showed that the water temperature ranged of 26-28°C, brightness 100%, current speed ranging between 0.05 ms-1and 0.19 ms-1, and salinity of 30-32 ppt. The water quality values showed a normal range which support the life of the coral and A. planci. The Percent coral cover ranged of 54.95-73.00% indicating a good condition. The abundanceof A. planci was of 0.02-0.03 ind/m2. Result showed that coral cover percentage and the abundance of A. planci did not have a significant relationship. Eventhough an A. planci eats the coral polip, but with small amount of A. planci in the coral reef, they merely help to clean the old and unhealthy polip. This activity will help corals to regenerate their polip. Overall, based on the small abundance of A. planci and the relatively high coral cover percentage, the coral reef ecosystem in Tunda island was categorised in a healthy condition. Keywords: A. planci, coral reef, Tunda Islan
DISTRIBUTION OF HEAVY METALS IN NATUNA COASTAL WATERS
Get PDFABSTRACTThe study of Pb, Cd, Cu, Hg, and As and Fe in Natuna coastal waters, Riau Islands was conducted in November 2012. Water and sediment samples were collected from 35 stations by purposive sampling method and those heavy metals were analysed using Atomic Absorption Spectrophotometer, flame type (FAAS). The results showed that concentrations of total Pb, Cd, Cu, Hg, and As in surface water were below instrument detection limit (2 µg/L for Pb, Cd, and Cu; 0.02 µg/L for Hg and As). Moreover, the concentration of metal Fe in surface water was 0.021-0.054 mg/L. Concentrations of Pb and Cu in sediment were 0.05-22.67 mg/kg and 3.77-11.00 mg/kg, respectively, at which the highest concentrations were found near Binjai Estuary. Those concentrations were significantly below the standard levels set by CCME (2002) and ANZECC/ARMCANZ (2000). Concentration of Fe in sediment varied from 751.13-2309.12 mg/kg and showed similar spatial distribution to Cu-in-sediment. No standard level for Fe in waters was available. Generally, it can be concluded that Natuna coastal water was still uncontaminated. Keywords: heavy metals, iron metal, Natuna coastal waters
PHYTOPLANKTON COMPOSITION AND ITS RELATION TO PEARL OYSTER AQUACULTURE (Pinctada maxima) IN SEKOTONG, WEST NUSA TENGGARA
Get PDFPearl oyster aquaculture is one of the marine industries that is currently growing in West Nusa Tenggara. Pearl oyster (Pinctada maxima) is a common species of oyster that cultivated in West Nusa Tenggara waters. A suitable location is an important factor for the success of pearl aquaculture industry. It needs a good water quality and supported by appropriate physical parameters for other marine biotas. The aim of this research was to analize phytoplankton composition (biological parameter) and it correlation to the Sekotong water condition for pearl farming production. The result showed that the pearl farming location has good water condition according to physio-chemical parameter and water nutrients. All parameters were in suitable range for the growth and development of pearl oysters. Keywords: pearl farming, phytoplankton, Pinctada maxima, West Nusta Tenggar