The act of swimming in formation by species such as Euphausia superba, Antarctic krill, is assumed to be regulated by a sensitivity to the characteristic and spatially elaborate flow field produced by this species of shrimp. We used a related species, Meganyctiphanes, North Atlantic krill, to visualize the flow field produced by tethered shrimps in an aquarium. In this situation, the propulsion jet flow some centimeters behind the shrimp is surrounded by a vortex ring of recoiling water motion from which, if the vortex is also produced by unrestrained swimming shrimp, a following shrimp hypothetically can draw forces of lift and propulsion to decrease energy expense in long-distance migration. Two antennular sensitivities to water vibration in frequency ranges 5-40 and 40-150 Hz were calibrated, and the activity of connected interneurons was traced into the abdominal pleopod-carrying segments. Water oscillation of 3-10 Hz frequency, applied to the antennules, was shown to entrain a closely synchronous pleopod beat in the stimulated specimens.

Abstract. Pricillia CC, Patria MP, Herdiansyah H. 2021. Environmental conditions to support blue carbon storage in mangrove forest: A case study in the mangrove forest, Nusa Lembongan, Bali, Indonesia. Biodiversitas 22: 3304-3314. Mangrove ecosystems can provide ecosystem services to mitigate climate change by absorbing and storing carbon in their systems. The question arises of how to manage a mangrove forest to store more carbon. The Nusa Lembongan mangrove forest was examined to assess the optimal environmental settings for blue carbon storage in the mangrove ecosystem. Five stations were selected purposively. The parameters observed in each station were aboveground living biomass, mangrove stand density, clay percentage in soil, bulk density, water content, soil organic carbon (%C), and soil organic nitrogen (%N). Based on this study, the total carbon stock in mangrove forest Nusa Lembongan was 68.10 ± 20.92 Mg C ha-1 and equals to 249.95 ± 76.77 MgCO2 ha-1 with a significant contribution of soil carbon stock. This study indicates that the essential parameters that can promote carbon sequestration in mangrove forest Nusa Lembongan were aboveground living biomass, soil organic carbon content and soil organic nitrogen content. In addition, as soil organic carbon content also negatively correlates with bulk density, it also can be considered. These findings can contribute to blue carbon planning and management to improve the effectiveness of the blue carbon project.

Anadara granosa is an important food source for people in Tanjung Jabung Barat District, Jambi. This study uses samples of cockle, sediment and water. The results showed a 100% sample containing microplastic. The types of microplastic found are fiber, fragments and films. The average microplastic amount in A. granosa individuals was 434 ± 97.05 particles/individuals. Fiber is the type of microplastic that is most commonly found in samples of cockles, sediments and water. In the blood cockles sample, fiber was found as much as 180.6 ± 21.22 particles/individual and 4.1 ± 0.43 particles/g cockle. Fiber is also found with high concentration in water samples of 128.3 ± 0.15 particles/L. The river is indicated as a microplastic source to the sea. The station sample 1 in 100 m near the river mouth has a higher microplastic concentration with an average of 448.3 ± 53.92 microplastic/individual, compared to station sample 3 which is only 420.3 ± 42.66 microplastic/individual.

Abstract. Nugroho D, Patria MP, Supriatna J, Andrianto L. 2016. Biological characteristics on three demersal fish landed in Tegal, north coast of Central Java,. Java Sea has a potential marine biodiversity that has been harvested since years. Demersal fish resources is one of the targeted species by Danish seine fisheries operated in North coast of Java. To support on developing conservation and management measures, an observation on species composition, length frequencies and maturity stages were carried out during August 2014 to July 2015. Sampling took place in landing place of Tegalsari fishing port central Java. A total 129 fish species identified, among them 91 species were targeted as edible fish. Sampling on three dominant species i.e., Purple-spotted bigeye Priacanthus tayenus (Richardson, 1846) . Monthly average GSI of P. tayenus and S. taenioptera indicated that the highest index occurred during SE monsoon while U. sulphureus on NW monsoon. Maturity stage analysis indicated that estimated of length at first maturity (L m ) were at 12.9 cmFL (U. sulphureus), 16.8 cmFL (S. taenioptera) and 19.4 cmFL (P. tayenus). Size frequency distribution shows that most of the fish were caught at immature cohorts. The diversity or evenness indices of ichtyofauna is also described as descriptors of community structure and be complemented with information on biological characteristics of those dominant species.

Jakarta contributes to 12% of the plastic pollution in Indonesian waters. Most of the plastic trash is mismanaged and end up accumulating in river mouths located along Jakarta Bay. This research analyzed the abundance and types of microplastic in milkfish Chanos chanos, surface water, and sediment of milkfish aquaculture ponds in Muara Kamal and Marunda, Jakarta Bay. Samples of each subject were obtained from each location. Digestive tracts extracted from milkfish were destructed with strong nitric acid. Water samples were filtered while sediment samples were dried. Concentrated NaCl solution was used to achieve microplastic flotation. Counting of particles was done under a light microscope. Overall results from Muara Kamal showed the microplastic abundance was 9.58±3.3 particles g−1 in milkfish digestive tracts, 103.8±20.7 particles L−1 in water, and 111,680±13,204 particles kg−1 in sediments. Microplastic abundance was found lower in samples from Marunda with 8.80±2.7 particles g−1 in milkfish digestive tracts, 90.7±17.4 particles L−1 in water, and 82,480±11,226 particles kg−1 in sediments. These results were consistent with the water pollution levels obtained by the Living Environment Agency DKI Jakarta that states heavier pollution by Pollution Index in Muara Kamal drain than in Marunda drain.

Abstract. Sari N, Patria MP, Soesilo TEB, Tejakusuma IG. 2019. The structure of mangrove communities in response to water quality in Jakarta Bay, Indonesia. Biodiversitas 20: 1873-1879. The waters of Jakarta Bay, which is a habitat for mangrove vegetation, have been polluted caused by many human activities such as development of housing, industry, tourism and facilities along the coast, and reclamation of man-made islands. The islands reclamation has caused changes in ocean current pattern and has impacts on material mobilization in the waters. The mangroves have experienced degradation as well since long time ago. The purpose of this research was to investigate the responses of mangrove vegetation to the quality of water in disturbed areas in Jakarta Bay to be used as baseline information for mangrove forest management in the area. Analysis of vegetation was used to examine mangrove community structure with the results were then related to the measurements on water quality using simulation modeling. The results show that mangrove forests in Jakarta Bay have an average Important Value Index (IVI) for all levels of life stage 95.7% with relative density of 28.85%, relative frequency of 29.21%, and closure relative of 38.62%. These results indicate that the mangrove forests in Jakarta Bay are under the criteria of damaged or disturbed according to the Minister of Environment Regulation. The mangrove forests were dominated by Avicennia marina, Avicennia lanata, Rhizophora apiculata, Sonneratia caseolaris, and Sonneratia alba. The average of ocean current velocity was 0.04-0.08 m/s. tides were single type with short waves generated by wind. The water discharge from 13 rivers were 205 ± 97 m3/s and the water discharge from power plant 224.9 m3/s. The heavy metal whereas The average pH was 7.75; Dissolved Oxygen 4.68 mg/L; turbidity 5 m; Total Suspended Solid (TSS) 50.95 mg/L; and salinity 6.6 ‰. The result of grain size analysis showed that most sediments obtained was in the form of silt with a mixture of little clay and sand. The responses showed that there was a reinforced pattern for pH, temperatures, rainfall, brightness, sediment, DO, and ocean current, with a trend of exponential growth in two years next of important value index of mangroves in response to water quality in Jakarta Bay. The heavy metals of Pb have concentrations of 65-104 ppm in sediments and 38-60 ppm in the water column; Zn has 150-258 ppm in sediment and 42-140 ppm in water column; Cu has 34-72 ppm in sediment and 13-30 ppm in water column; Ni has 33-39 ppm in sediment and 40-50 ppm in water column; Cd has 5.9-8 ppm in sediment and 8.5-15 ppm in the water column. The heavy metals, TSS, and water river discharge have balance-decay pattern. The amount of river water discharge entering Jakarta Bay, the heavy metals, and the low level of ocean currents cause coastal waters of Jakarta Bay to become muddy puddles that cannot flow properly. These conditions make the mangrove forest habitat becomes polluted and the mangrove vegetation degraded. Therefore, all of these things need to get serious attention so the mangrove forests can be restored and the function of mangroves can return to normal.

Research on the abundance of microplastic in green mussel Perna viridis, water and sediments in Kamal Muara, North Jakarta in September 2017 has been done. The research determined the abundance of microplastic in water, sediment and green mussel (base on the sizes and microplastic storage organs), also the correlation between abundance of microplastic in green mussel, water and sediments. Samples of green mussel, water and sediments were taken from 3 different stations with a distance of about 500 meters. Analysis of abundance of microplastic was done by isolating microplastic in each sample. The isolation of the green mussel samples was done by dissolving the mussels in the HNO3 solutionfor 24 hours and added saturated NaCl solution. The microplastics from water and sediment samples were separated by immersion of samples in a saturated NaCl solution. The results obtained were, on average, abundance of microplastic in green mussel size 3, 6, and 9 cm i.e., 5.35; 24.99; and 39 particles/gram. The microplastic fiber was dominant in mussel sample. The average abundance of microplastic in water and sediment are 13.15 particles/L of sea water and 0.92 particles/gram of dry sediment respectively. The microplastic film was dominant in water and sediment samples. Meanwhile, pellet was not found in all three samples. There was a correlation between abundance of microplastic with green mussel size, as well as with abundance of microplastic of film and fiber in water and sediment.

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