Marine Research in Indonesia (MRI - E-Journal)
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MEASURING SEA SURFACE SALINITY OF THE JAKARTA BAY USING REMOTELY SENSED OF OCEAN COLOR DATA ACQUIRED BY MODIS SENSOR
No full textObservations on oceanographic parameters using remote sensing techniques intensively have been done for more than 3 decades for estimating and mapping the sea surface temperature (SST) and the abundance of phytoplankton expressed as the concentration of chlorophyll-a and applied them in studying the ocean phenomenon. As a result, the product of these 2 parameters for all over the oceans in the world has been established and available in daily basis. However, on the contrary, there is still limited application for sea surface salinity (SSS) which is also one of the most important oceanographic features. This paper describes a novel method of deriving SSS from remotely sensed ocean color. The method is based on two important observations of optical properties in regions of freshwater influences. The first is the strong effect of Colored Dissolved Organic Matter (CDOM or yellow substance) on ocean color when present in relatively high concentrations. The second is the close relationship between salinity and CDOM originating from fresh water runoff. In this paper, these relationships are demonstrated for the Jakarta Bay, Indonesia. The MODIS sensor in Terra and Aqua satellites imageries and 10 in situ measurements conducted near-simultaneously with the satellites over flight over the bay in 2004 and 2006 were implemented for deriving CDOM and SSS. The empirical relationships demonstrated in this study allow the satisfactory prediction of CDOM and SSS in the Jakarta Bay from remotely sensed ocean color. The root mean square (r.m.s) error difference between the observed and predicted parameters are 0.14 m-1 and 0.93 psu for CDOM g440 g and SSS, respectively, over a range of salinity from 24 to 33 psu. This range is in good agreement with field surveys. Parameters that may influence CDOM, such as Chlorophyll-a (CHL-a) and total suspended material (TSM) concentrations were also analyzed. Results showed that there were no relationship at all between CDOM and CHL-a, and between CDOM and TSM. These indicate that phytoplankton plays a minor role in regulating CDOM abundance, and also suggest that CDOM contribution from sediment and/or from sediment resuspension is negligible. Thus, CDOM sources in the Jakarta Bay are mainly from riverine inputs. SSS maps created from the satellite-retrieved ocean color identify features in the surface salinity distribution such as salinity front of > 32 psu that migrated in and out of the bay according to seasons. Therefore, the ability to obtain synoptic views of SSS such as presented in this paper provides great potential in furthering the understanding of coastal environments
AMPHIPOD DISTRIBUTION IN THE SOFT-BOTTOM SUBTIDAL ZONES OF JAVA ISLAND IN RELATION TO SEDIMENT TYPES
No full textAmphipods inhabit many marine benthic habitats and have an important ecological role. However, there is a lack of information about Indonesian amphipod diversity and distribution, especially in the shallow subtidal sediments of Probolinggo and Tangerang. During the transition to the monsoon season in September 2014, eight subtidal stations were sampled in Bayeman (Probolinggo) on East Java and seven subtidal stations were sampled in Kramat Kebo (Tangerang) in West Java. A total of 7346 amphipods individuals were collected, comprising five genera. Genus Photis was the most abundant group, followed by Grandidierella and Synchelidium. Multivariate analyses of these data indicated that sampling location and sediment granulometry were major determinants of distribution and composition of amphipods in Probolinggo and Tangerang
SEASONAL CHANGE IN THE DIEL PATTERN OF THE PSEUDO-NITZSCHIA POPULATION IN THE CISADANE RIVER ESTUARY: RESPONSE TO THE CHANGES IN THE WATER’S PHYSICAL-CHEMICAL PARAMETERS
No full textSeasonal changes of Pseudo-nitzschia diel dynamics in an estuarine ecosystem have been known to be regulated by salinity, water temperature and nutrient dynamics. In this study, we aimed to investigate the effect of these physical-chemical factors on the diel pattern of the Pseudo-nitzschia population in the Cisadane River estuary.Plankton samples were collected from a diel station at two different periods, in the dry season (May-June) and thewet season (September). Plankton samplings were done in a 24 hour period with 3 hourly sampling intervals. The result showed a higher abundance of Pseudo-nitzschia in the dark-period during the dry season, while during the wet season the abundance was higher in the light-period. Nitrate and phosphate concentrations were suggested as important factors in facilitating Pseudo-nitzschia maxima. The low abundance of Pseudo-nitzschia in the estuarycould be due to the relatively low N:P ratio (<10). The results showed that the Cisadane River estuary was strongly influenced by seawater during the night and by freshwater during day. The GLM analysis suggested that there were changes in the species omposition of the Pseudo-nitzschia population in the ecosystem. The oligohaline species was found to be abundant in the dry season, the maxima occurred at night, which is probably related to a highermarine influence in the ecosystem. Conversely the polyhaline species was abundant in the wet season, with the maxima occurring during daylight, which might be related to a stronger freshwater influence in the ecosystem
THE ELASMOBRANCH NURSERY AREA OF JAKARTA BAY
No full textA study on the correlation between water, sediment qualities and the diversity of elasmobranchs in Jakarta Bayhas been conducted by the Research Center for Oceanography from the beginning of 2012. This paper presents apart of the study focusing on elasmobranch diversity and its size composition. Elasmobranchs in the coastal area ofJakarta Bay were collected using bottom gillnet every month to find out the species diversity and its size composition.The 162 collected individuals from Jakarta Bay were classified into eight species of rays and one whaler shark.Himantura gerrardi, H. uarnacoides, H. walga and Neotrygon kuhlii were the most common species found in thisarea. Interestingly, most specimens found in the area were immature and new born animals. This finding indicatesthat the coastal area of Jakarta Bay is one of nursery areas of most elasmobranchs living in adjacent waters althoughthe bay has been heavily polluted
UTILIZATION OF ALGINATE AS AN ENCAPSULATION MODEL OF COCONUT SHELL LIQUID SMOKE
No full textAlginate extracted from brown seaweed has gelling properties that make it useful as a wall material in encapsulation systems. Liquid smoke contains the active substances, such as phenols, which can preserve food. In order to protect the active substances, liquid smoke is encapsulated by using alginate and maltodextrin. The purpose of this study was to investigate liquid smoke encapsulation technology with maltodextrin and alginate using a spray dryer, to improve the physical and chemical characteristics of the liquid smoke. The microcapsules of liquid smoke were made, using a spray dryer SD 04, by encapsulating liquid smoke with two types of wall materials, maltodextrin and the combination of alginate- maltodextrin. The ratio of liquid smoke to total solids (wall materials) was 9:1 (v/w). The alginate concentration used was 0.5 to 2% (w/v). Parameters observed in this study were phenol release, shape and morphology, encapsulant efficiency, drying yield, phenol marker and, particle size. This study used a completely randomized design with three replications. The best treatment was obtained by using the alginate with a concentration of 1% (w/v) and maltodextrin of 9% (w/v) with phenol release of 2.52% (w/w) in the 20 minute of release, encapsulant efficiency of 45.13% and drying yield of 28.74%. The particle size analyzer results showed that the particles were agglomerating. Scanning electronic microscope (SEM) observation illustrated that all treatments have a better capsule morphology than the controls, whereas Optilab image processing and analysis software results showed that phenolic compounds are encapsulated by wall materials used.
INFLUENCE OF STRONG MONSOON-DOMINATED CLIMATE ON BIOGEOCHEMISTRY OF THE HEAVILY ANTHROPOGENIC IMPACTED BRANTAS RIVER ESTUARIES AND MADURA STRAIT COASTAL WATER, EAST JAVA, INDONESIA
No full textBrantas River basin and Madura Strait in East Java Indonesia, are subject to heavily change in land use and land cover, and Brantas River Basin is a very important densely populated area in East Java, Indonesia for agriculture, industry as well as for settlement. The aim of the research is to elucidate the fate of transformation of bio-elements (organic carbon, Nitrogen (N), Phosphorus (P), and Silicate (Si)) and its seasonal variability. The contrast river discharge combined with tide generates the distinctive mixing zone during rainy and dry season. Dissolved Inorganic Nitrogen (DIN) and Dissolved Inorganic Phosphorus (DIP) concentrations in the river are high and decrease to the very low value seaward. N:P ratio has seasonal variation due to large discrepancy of DIN and DIP supply from land to the sea. Dissolved Inorganic Silicate (DSi) in river and estuaries is extremely higher than the average in the world (> 150 mM). Chlorophyll-a (Chl-a) in dry season in the coastal water is higher than the rainy season. Due to high Total Suspended Matter (TSM), the primary production is limited by the light in the coastal water
BENTHIC HARMFUL DINOFLAGELLATE ASSEMBLAGES IN A FRINGING REEF OF SAMPADI ISLAND, SARAWAK, MALAYSIA
No full textA study on the presence and relative abundance of benthic harmful algal bloom (BHAB) forming dinoflagellate species was carried out in the coral reefs of Sampadi Island, Sarawak, Malaysia. The study involved deployment of fiberglass screens as an artificial substrate for the benthic epiphytic microalgae. The screens were placed for 24 h above the seafloor along a 100 m transect at 10 m intervals. BHAB species attached to the screens were identified and cell abundances were enumerated under a light microscope. The BHAB community at the study site was dominated by Prorocentrum spp. and Coolia spp. Other BHAB species collected included Amphidinium spp., Gambierdiscus spp. and Ostreopsis spp. Total cell densities collected on the screens ranged from 5 to 100 cells per 100 cm2. The two BHAB groups of primary concern, Gambierdiscus spp. and Ostreopsis spp. were detected at relatively low abundances of 0.6–4.2% and 1.8–16% respectively. This study has shown that potentially toxic BHAB species were present in the coral reef and the artificial substrate approach could provide a convenient quantitative method for the collection of clean samples for identification and enumeration purposes
THE CONDITION OF CORAL REEFS IN WEST BANGKA WATER
No full textBangka Island is well known as the world’s largest tin producer. The inland and offshore tin mining has profound effects on the coastal environment, resulting in the high sedimentation in the water. Many corals suffered physiological damage due to low light intensity. The distribution of stony corals and the status of coral reefs was surveyed at 6 sites in West Bangka waters in October 2012. A total of 72 species of corals belonging to 33 genera and 12 families were found, and 4 species were distributed at all research sites. The live coral coverage was 36% on average and was categorized as being in fair condition. The coverage was 0% at Kamboja Island where the corals were the most affected by tin mining. The sediment flowed out from tin mining, blocked the light, and settled on the corals’ surface. Consequently, many corals were buried and the live corals decreased. It is obviously necessary to reduce and control the tin mining
NEW RECORD OF INDONESIAN PIGFISH, BODIANUS IZUENSIS ARAGA AND YOSHINO, 1975, AND B. MASUDAI ARAGA AND YOSHINO, 1975 (PERCIFORMES: LABRIDAE), FROM NORTH SULAWESI, INDONESIA
No full textOne specimen of Bodianus izuensis Araga and Yoshino, 1975, and three specimens of B. masudai Araga and Yoshino, 1975, were obtained from fish markets in Bitung and Kema, Minahasa, North Sulawesi, Indonesia, between March–July 2009. The specimens were caught from depths of about 20–30 m at coral reef ecosystem around Lembeh Island and Kema. This is the first record of these species in Indonesian waters. Morphological features, diagnostic characters, and distribution are discussed and illustrated, and color photographs of the species are presented
TEMPORAL VARIATION IN CERATIUM SPP. ABUNDANCE RECORDED IN JAKARTA BAY
No full textCeratium is non-toxic dinoflagellate which has been regarded as the most common bloom-forming species in the coastal waters around the world. Eventhough research and monitoring on phytoplankton In Jakarta Bay have been conducted for long enough, no specific attention has been given to Ceratium community. Therefore, a research was set up in order to understand the dynamic of Ceratium population and its regulating factors. A serial sampling was conducted in 10 stations during 2009 and 2010. Phytoplankton was sampled in horizontal towing using Kitahara plankton net (80 μm mesh size, 0.5 m mouth diameter and 1m length). Phytoplankton enumeration and identification were done by applying Fraction Method on Sedgewick Rafter Counting Chamber (SRCC). The result showed clear temporal variations in Ceratium absolute density, relative density, relative frequency and importance value. When phytoplankton bloomed in August 2009, no Ceratium bloom observed. High density of Ceratium was observed in November 2009 and May 2010, but it contributed relatively small proportion to phytoplankton as a whole (relative density <1%). Due to its low density and relatively limited distribution in Jakarta Bay, Ceratium may demonstrate limited ecological role to the phytoplankton community