Marine Research in Indonesia (MRI - E-Journal)
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STUDY ON SEA LEVEL RISE IN THE WESTERN INDONESIA
No full textStudy on mean sea level (MSL) rise has been done on tide data at some locations in the Western Indonesia. To account the effect of climate change, air temperature analyses from some weather stations are also performed. The results showed that air temperature has changed between 0.0 to 0.44°C per ten years. The sea level analysis showed that mean sea level at Western Indonesia rise between 3.10 to 9.27 mm per year. Based on the results, the prediction on mean sea level change in the years of 2000, 2030, 2050 and 2100 for Cirebon location are 17 cm, 39 cm, 55 cm, and 92 cm, respectively
REPRODUCTIVE PATTERNS OF HOLOTHURIA SCABRA (ECHINODERMATA: HOLOTHUROIDEA) IN INDONESIAN WATERS
No full textDuring 1993 to 1996, reproductive aspects of Holothuria scabra, one of the commercially important holothurian species in Indonesian waters were studied, which involved populations of Ambon Bay (eastern Indonesian waters), Saugi Island (central Indonesian waters) and Lampung Bay (western Indonesian waters). Those studies were reviewed in this paper, not only to reveal general patterns of reproductive seasons of populations throughout Indonesian waters, but also to provide more knowledge on gonadaltubule-development that has been rarely investigated on Indonesian holothurians. The review showed that the development of gonadal tubules amongst populations of Indonesian H. scabra were similar. Those included that: tubules across a gonad grew for one single reproductive cycle, and each tubule had equal opportunity to release their gametes in the same spawning event. These features conformed to general characteristics of this species throughout the world, and were different from the proposed tubule recruitment model of Smiley (1988). Each observed population showed fluctuation on gonad index, and individuals with fecund and/or post spawning gonads were recorded in most sampling occasions, resulting in fluctuation of gonad index. This attribute gave clue to through-year spawning activity with more intense during one or two periods in a year
GROWTH OF JUVENILE HORSE'S HOOF CLAMS (Hippopus hippopus) REARED IN COASTAL WATERS, PARI ISLAND, KEPULAUAN SERIBU
No full textThe main purpose of this present study is to determine the growth and survival rate of juvenile horse's hoof clams {Hippopus hippopus) and to find out a suitable site for their rearing in nature. Juveniles used in this study were about 3 years old, produced in the hatchery of CV Dinar, Bali. They were reared in the cages, placed on the sea bed at several sites, namely: (1) on the reef flat, (2) on the bed of a lagoon, and (3) on the sea channel. After 360days of rearing, the highest daily growth was found for juveniles reared in site-2, i.e. 0.110 mm in length, 0.080 mm in width and 0.091 mm in height. These values were significantly different from other two sites. The survival rate after 360 days of rearing was 85.5% in site-1, 99.4% in site-2 and 96.8% in site-3. Based on these results the bed of a lagoon is the best and suitable site to grow horse's hoof clam juveniles in nature. Water condition at this site is relatively calm with sandy-muddy substrates and relatively dense seagrasses, mainly Thallasia spp
NUTRIENT CONCENTRATION AND PH IN THE CISADANE ESTUARINE AND COASTAL WATERS
No full textThe study on the fluctuation of dissolved nutrient concentrations and acidity (pH) in the Cisadane Estuary was carried out in May 2004 October 2004 and July 2005. Inorganic phosphate, nitrate and silicate of the surface water were analyzed, using Spectrophotometer and pH was measured with a pH meter. Generally the nutrient concentrations in the estuary were higher compared to those in the coastal and offshore areas. The concentrations were gradually becoming lower and lower toward the open sea. Their fluctuation depended not only on the environmental condition but also on the water volurrie from the land and the mangrove forest in that area
ASSESSING CONTAMINATION LEVEL OF JAKARTA BAY NEARSHORE SEDIMENTS USING GREEN MUSSEL (PERNA VIRIDIS) LARVAE
No full textIndication of accumulation of heavy metal in sediments will lead to problem for shore and sea ecosystems, biota living in that area and human’s health. The research is aiming to analyse the toxicity of sediment from thirty one locations in Jakarta Bay using Perna Viridis. High amount in larval abnormality found in sediments from the area near mainland and estuary are an indication of high influence of waste from anthropogenic activities from Jakarta mainland. These areas are down stream of Cengkareng Drain, Kamal River, Grogol River and Cakung River, area around sea transportation and North Jakarta Integrated Industrial Area. Sediment of Jakarta Bay, especially coming from estuary area and near to the land area causes an increase in green mussel larval abnormality. This indicates the high of waste influence from anthropogenic activity from Jakarta land area
SUBMARINE GROUNDWATER DISCHARGE MEASUREMENT ON THE SANDY UNCONFINED AQUIFER AT THE CARNAVAL BEACH, ANCOL (JAKARTA BAY)
No full textSubmarine groundwater discharge (SGD) is defined as all direct discharge of subsurface fluids into coastal zone. Components of SGD consist of fresh submarine groundwater discharge and the recirculated saline seawater discharge. SGD could act as a pathway for the transport of anthropogenic contaminants and nutrients to coastal waters. Measurement SGD at Carnaval Beach, Ancol, Jakarta was focussed on unconfined groundwater system. The method of quantified used automatic seepage meter for measured of SGD and installed conductivity temperature depth. The average SGD rate was 0.21 mm/min on March 20-31, 2009 consist of 19.05% fresh water, 80.95% recirculated seawater. April 1-23, 2009, the average SGD rate was 0.81 ml/min which consisted of 16.04% fresh water, 83.96% recirculated seawater. SGD fluctuation was opposite with the tide. As a result, submarine groundwater discharge at Jakarta coastal area was defined and can be measured to quantify
PRISTINE MANGROVE COMMUNITY IN WONDAMA GULF, WEST PAPUA, INDONESIA
No full textPapua shoreline has the most extensive area of mangrove in Indonesia. Since this area was rarely studied due to various reasons, the scientific data was difficult to be found. Wondama mangrove, part of Cendrawasih National Park – West Papua, had a promising mangrove forest to be discovered. Preliminary study was carried out in this area to identify how pristine the mangrove area is. The objectives of this study was to analyze mangrove community health and structure. Vegetation structure and canopy coverage data were collected from 107 circular plots included three plot areas (radian: 5 m, 2.5 m and 1 m) which were distributed to determine three plant classes i.e. tree, sapling and seedling, respectively. Present study showed that Wondama mangrove is a pristine mangrove community. It had large size of tree trunk diameter by 19.77± 6.55 cm averagely. Its diameter size affected on low tree density which was less than 1000 tree/ha. Those two parameters were strongly negative-correlated each other. On the other hand, community canopy was highly covered mangrove area by 82.46±6.43%. Rhizophora has mostly dominated in the forest. Mangrove regeneration in Wondama was excellent referring to density and species composition of sapling-seedling levels
TAXONOMIC LEVEL NEEDED TO DETECT SIGNIFICANT CHANGES IN POLYCHAETE COMMUNITIES OVER DIFFERENT MACROPHYTE ASSEMBLAGES ON ROCKY INTERTIDAL SHORES
No full textEnvironmental degradation has more significant impacts on rocky intertidal communities after global changes increase progressively. Thus, ecological monitoring should be conducted properly to analyse potential drivers and their impacts. However, most of the ecological monitoring in rocky intertidal shores is more interested in macroalgae. Polychaetes associated with macrophyte assemblages should be also involved in the monitoring because they are important in determining coastal health and productivity. A successful ecological monitoring should consider three factors: taxonomic level, statistical power, and sample size. In this study, those factors were analysed in the relationships between polychaetes and macrophytes. Four taxonomic levels of polychaetes (i.e. order, family, genus, species) were tested based on 25 samples collected from rocky intertidal shores of Gunung Kidul, Yogyakarta, Indonesia. Relationships between each of taxonomic richness of polychaetes and each of macrophytes variables (i.e. species richness, biomass, species composition) were analysed using a Generalised Linear Models fitted by Poisson Distribution and log link. The statistical power of those relationships and the sample size needed to obtain a strong statistical power (>0.8) were also recorded. Relationships between each of taxonomic composition of polychaetes and each of macrophyte variables were analysed using a distance-based Redundancy Analysis based on Bray-Curtis dissimilarity on log(x+1) transformed abundance data with 999 permutations. Results showed that family-based data analysis was sufficient to detect significant relationships between polychaetes and macrophytes. However, the statistical power of most relationships was relatively weak (<0.8). Hence, the family-based data analysis should select a 44-sample size to gain significant relationships with a strong statistical power.
EVALUATION OF COREMAP PHASE 2 IN THE EASTERN INDONESIA BASED ON THE CHANGES IN CORAL COVERAGE
No full textCOREMAP (Coral Reef Rehabilitation and Management Program) is a long-term program initiated by the Government of Indonesia to enhance the welfare of the coastal communities by protecting, rehabilitating, and achieving sustainable use of the Indonesian coral reefs and their associated ecosystems. COREMAP is three phases planned program. The first phase was launched in 1998 and finished in 2004. Phase 2 began in 2006 and ended in 2011. The last phase has started since the end of 2014 and will finish in 2019. One of the performance indicators of COREMAP phase 2 (COREMAP 2) was a significant improvement of live coral cover in 80% of all sampling sites. The aims of this study are to find out and evaluate the trend of live coral cover during COREMAP 2. Annual monitoring of coral reefs was conducted in all sites of COREMAP 2 in the eastern Indonesia. Those sites were: Pangkep, Selayar, Buton, Wakatobi, Sikka, Biak Numfor and Raja Ampat. Permanent transects were applied at each site. Life-form of benthic data including hard corals was collected using the Line Intercept Transect (LIT) method and surveyed using SCUBA diving equipment. The result indicates that all sites, except Biak Numfor, demonstrate improvement in live coral cover during COREMAP 2. In contrast, live coral cover in Biak Numfor shows a decline due primarily to storm damage, destruction by bombs, some bleaching, and predation by Acanthaster planci. An increase in live coral covers in six out of seven sites during COREMAP 2indicates that the activities of COREMAP 2 (e.g. public awareness, community-based MCS, alternative livelihood) has a positive impact on the management of coral reefs in the Eastern of Indonesia
NOTES ON THE RECORD OF GOBLIN SHARK (Mitsukurina owstoni Jordan, 1898) FROM INDONESIA
No full textA goblin shark, Mitsukurina owstoni,was captured by deepwater shark longline targeting squaloid sharks off Palabuhanratu, West Java, Indonesia at about 200 m depth. Morphological measurements were taken and compared to other records from Australia, New Zealand and Japan. This new recordfrom Indonesian waters extends the distribution of this species in the Indian Ocean