Marine Research in Indonesia (MRI - E-Journal)
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SEDIMENT DEPOSITION IN A SOUTH SULAWESI SEAGRASS BED
No full textDeposition of suspended sediment was measured with sediment traps in shallow coastal waters colonized by Thallasia dominated seagrass in Pannikiang Island, South Sulawesi (Indonesia). The primary objective of this study was to compare the amounts of sediment deposition inside seagrass beds and in adjacent unvegetated area. The traps were placed in a seagrass bed (Station I, II, and III) and in an adjacent unvegetated area (Station IV) measuring the sediment flux on the seabed. The sediment fluxes due to deposition were significantly higher at stations I and II (P < 0.05) and station III (P < 0.01) than at station IV (unvegetated area). Results of this study suggest that sediment deposition was promoted by dense shoots of seagrass. The study provides quantitative evidence for the importance of seagrass bed as sites of sedimentation of fine particles.
ASSESSMENT OF IMPACT OF THE SOLAR I OIL SPILL ON THE INFAUNAL ASSEMBLAGES OF SOUTHERN GUIMARAS, PHILIPPINES
No full textThe study was conducted between September and October 2006 in various sites both inside and outside the Taklong Island National Marine Reserve (TINMAR), southern Guimaras, Philippines, to immediately conduct a rapid 3-month assessment of the impact of the Solar I oil spill incident which occurred in August 11, 2006 in southern Guimaras. The assessment was made possible by the availability of baseline (pre-spill) data which were compared with the present data (post-spill). Results showed the drastic decrease in overall mean densities (no. m-2) and species richness in the infaunal assemblages within TINMAR in September 2006, or 1 month after the oil spill. In October 2006 however, a slight increase in both of these parameters was observed, albeit not significant. The decrease is taken as a disturbance, directly resulting from the oil spill. On the other hand, it is not clear at this time if the increase is the start of recovery in the infauna. Our results indicate the need for a continuous monitoring, to allow more definitive conclusions on a) whether the assemblages are recovering, and if indeed they are, b) how long this recovery will take place.
ISOLATION OF ASP TOXIN-PRODUCING NITZSCHIA FROM THAILAND
No full textNitzschia navis-varingica is recognized as the major ASP toxin producer other than Pseudo-nitzschia species. Surveys on the distribution and the toxin production of this diatom has been conducted in a few countries in eastern Asia and expanded to Thailand. Eighteen isolates from Thailand showed the positive result for the ASP toxin production is DA and IB, although the ratio of IB was much lower than those of the isolates from southern countries including Okinawa, Japan, the Philippines and Vietnam
OCCURRENCE OF Gymnodinium catenatum IN THE GULF OF THAILAND
No full textA clonal culture of Gymnodinium catenatum was established from a plankton sample collected from Leamthan, Chonburi Province, in the Upper Gulf of Thailand. The culture was maintained at 28±1°C under light intensity of 70 [tmol photons m-2 s-1 with 12:12 L:D cycle. Cells were harvested at late exponential phase and extracted with 0.03 M acetic acid. The HPLC analysis on thus obtained extract revealed that toxins consist of N-sulfocarbamoyl toxins, Cl and C2, as major components. GTX1, GTX2, GTX3, GTX4 and dcSTX were also detected as minor components. The toxin profile of this clone is different from clones of G. catenatum found in Singapore which was dominated by the highly potent carbamate toxins, primarily GTX 1 and 4 with less amounts of GTX2, GTX3, neosaxitoxin, and saxitoxin. No N-sulfocarbamoyl, decarbaomyl, or deoxy-decarbamoyl toxins were detected
SEASONAL FLUCTUATIONS IN THE SURFACE SALINITY OFF THE NORTH COAST OF JAVA
No full textThe division of the region investigated according to P. CH. VEEN is redescribed. The micro salinity titration by means of the method described by G. H. ARNOLD with an accuracy of 0.1 ‰ was used for this investigation. This technique was adopted because of the large number of observations, and was sufficiently accurate since salinity in these waters varies widely. The annual range in salinity is large, caused by a considerable discharge of fresh water from the many big and small rivers, especially in the rainy-season as well as by the inequality of salinity of the oceanwaters coming from the East, and the South China Sea water coming from the West, during the dry and wet-sason respectively. In the east-monsoon, the eastern section is covered with ocean water over 34.0 ‰ and the western section with mixed waters ranging between 31.5 ‰ and 34.0 ‰, while in the west-monsoon, the area is covered with mixed water less than 32.5 ‰
LABORATORY CULTURE OF THE SEAGRASS, Halophila ovalis (R.BR.) HOOKER F.
No full textA small-culture system for growing of Halophila ovalis was developed. Plugs of explants were successfuly grown in the native substrate and under the light regime of ~200 imol m-2 s-1. The culturing of H. ovalis in the laboratory permitted observations on (i) the sustain growth and the development of the population, (ii) the reproductive biology (flowering and fruiting) and (iii) the pattern of seedling development from seeds to mature plants. Plants increased in density via vegetative propagation and sexual reproduction. Plants produced male, female flowers and fruits. The presence of viable seeds and seedlings demonstrated the successful pollination and sexual reproduction of H. ovalis in culture. The morphology of progressive development of H. ovalis seedlings to juvenile or young plants for H. ovalis in culture is described
CHEMICAL PROPERTIES IN THE CONSERVATION AREAS OF GILIMANUK BAY, WEST COAST OF BALI
No full textThe study on chemical properties in the conservation areas of Gilimanuk Bay, west coast of Bali was carried out in March 2006. The dissolved oxygen and degree of acidity (pH) in surface water were analyzed. The nutrients, consisting of phosphate, nitrate and ammonia concentrations in water were analyzed as well. In general all the chemical parameters were normal for coastal waters. Dissolved oxygen in this area was lower than those in Jakarta Bay and Panimbang waters, while the nutrient concentrations were lower compared to those of Cisadane Estuary, but higher compared to those of Mamberamo Waters. The fluctuations of pH, dissolved oxygen and other nutrients were influenced by the condition of surrounding area
STUDY OF MICROBIAL POLLUTION IN THE ACEH COASTAL WATERS AND ITS VICINITY
No full textStudy of microbial pollution in the Aceh coastal waters and its vicinity were carried out in the period of August - September 2006. The purpose of the study is to monitor the marine and coastal environments related to the bacterial condition in Aceh waters after the tsunami disaster. The sediment and water samples were collected from 28 stations in four sites in the Aceh waters (Eastern Aceh, Northern Aceh, Western Aceh and Simeulue Islands waters), using the RV. Baruna Jaya VIII. The determination of microbial pollution was based on parameters of coliform and pathogenic bacteria. The coliform bacteria was analysed by membrane filter technique and pathogenic bacteria (Salmonella and Vibrio) by isolation method based on the selective culture media of Salmonella and TCBS agar. The results of the study showed that density of total coliform bacteria varied between 40 and 1055 CFU/100 ml with an average of 443 CFU/100 ml. Based on the pattern of the distribution of coliform bacteria it was found the highest number in Eastern Aceh with the value of 611 CFU/100 ml and the lowest number in Western Aceh with the value of 348 CFU/100 ml. Based on the density of coliform bacteria, Aceh waters was in the lower permissible level of the Indonesian and WHO standards, means that the coastal environment in Aceh waters is still in good condition. Four genera of pathogenic bacteria isolated from seawater samples were Pseudomonas, Citrobacter, Aeromonas and Proteus, and 6 genera from sediments samples were found i.e. Pseudomonas, Citrobacter, Aeromonas, Yersinia, Proteus and Vibrio. The pathogenic bacteria from the samples such as Salmonella typhy and Vibrioparahaemoliticus had low pathogenic potential. This indicated that the risk of pathogenic bacterial contamination in Aceh and its vicinity waters were relatively low, therefore, the conditions of coastal and marine environments were relatively in good condition.
SEABIRDS IN THE BANDA SEA IN FEBRUARY/MARCH 1985
No full textQuantitative seabird data were collected in February/March 1985 in the Banda Sea. Comparison with similar data for August 1984 indicated no monsoonal influence on seabrid abundance; the median for both periods falls within the 1-5 birds per hour class.The area around the breeding island Manuk was relatively rich in both periods. Birds breeding here are "blue ocean" seabirds, foraging over large areas. Apparently, not food abundance but suitable breeding place determines their abundance here. Manuk has an enormous importance for the seabird population in the Banda Sea area, fortunately, it is a nature reserve since 1981. The breeding period on Manuk is not short and related to the NE monsoon, but extended over a larger period of the year. Manuk was known already as a breeding island in the 17th cnetury, but this knowledge was lost and only recently Manuk was "rediscovered" as such.A second relatively rich area occurred again south of Irian Jaya. Migrating birds dominated here. They probably visit this area because of relatively high food availability. Species differed for both periods. Streaked Shearwaters which breed on the northern hemisphere had in February/ March replaced the antarctic Wilson's Stormpetrel which abounded here in August 1984, but had now returned to its breeding area
MOLECULAR PHYLOGENY OF LEIOGNATHIDAE IN THE WATERS OF PERHENTIAN ISLANDS, TRENGGANU, MALAYSIA
No full textSeveral series of trawl surveys were carried out in the waters of Perhentian Islands using commercial trawlers. 16S mitochondrial rRNA gene sequences were used to infer the phylogenetic relationships among nine morphospecies of leiognathids. The results showed that the genus Leiognathus is paraphyletic, whereas Gazza secutor, Photoplagios, Photopectoralis and Nuchequula are monophyletic. The molecular phylogenetic posions of the leiognathids studied were identical with morphological delineation, except for Photoplagios stercorarius. Branch of P. stercorarius was placed between Photoplagios spp. clade and clade of Secutor and Gazza. P. stercorarius was more affiliated to genus Photoplagios morphologically however have slight different features of light organ system compared with others three Photoplagios sp. caught in this study. It is probable that two distinct subclades occur in genus Photoplagios. Leiognathus equulus formed the base of the other leiognathids. Leiognathus splendens and Leiognathus jonesi formed a sister taxa to Photopectoralis species. Gazza formed a sister taxa to Secutor and Nuchequula formed a sister taxa to the group of trifurcation but toth with low bootstrap support. This study has shown that 16S mitochondrial rDNA is a good marker for phylogenetic analysis of the Leiognathidae