Jurnal Ilmu dan Teknologi Kelautan Tropis
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CHEMICAL PARTIONING OF Cu AND Fe IN SURFACE SEDIMENTS ON THE EAST AND WEST COASTS OF NORTH SUMATRA
Get PDFMobilitas (termasuk proses desorpsi-absorpsi) logam berat dalam sedimen bervariasi yang bergantung pada asosiasinya pada komponen mineral dan non-mineral sedimen yang dapat juga mengindikasikan pada sumber alami dan non-alami. Penelitian ini bertujuan mengungkap kemungkinan sumber logam berat Cu dan Fe berdasarkan fraksinasi dan total logam. Lokasi penelitian terdiri dari 11 titik yang terbagi menjadi tiga bagian pesisir timur, pesisir barat, dan Pulau Nias, Sumatera Utara. Fraksi geokimia diperoleh berdasarkan prosedur ektraksi bertingkat SEP BCR (Sequential Extraction Process Bureau Commune de Reference of the European Commission) dalam empat fase yaitu: Fraksi terlarutkan asam, fraksi tereduksi, fraksi oksidasi, dan fraksi residual. Total logam diperoleh berdasarkan metode USEPA 3050B. Pengukuran logam dilakukan dengan menggunakan spektrofotometri serapan atom (SSA). Hasil penelitian menunjukkan bahwa kegiatan antropogenik diduga menyumbang logam Fe dalam sedimen yang ditunjukkan oleh konsentrasi non residu (5,55-203,15 mg/kg) yang lebih tinggi dibandingkan fraksi residu (4,89-21,47 mg/kg). Berbanding terbalik dengan logam Cu yang asosiasi tertinggi adalah fraksi residu (2,24-8,85 mg/kg). Logam berat dalam sedimen mendapat kontribusi dari sumber alami dan antropogenik, logam Cu diduga bersumber lebih banyak secara alami dan logam Fe diduga bersumber lebih dominan dari aktifitas manusia (antropogenik) baik sekitar wilayah pesisir maupun kemungkinan berasal dari daratan.Mobility (including desorption-absorption) of heavy metals in sediments varies depending on the chemical properties of sedimentary minerals in which the metals are associated and hence possibly differentiate their origin (natural and anthropogenic). This study aims to reveal on Cu and Fe of origin based on their chemical fractionation and total concentration. The study location consisted of 11 points clustered into three parts i.e the east coast, west coast, and Nias Island of North Sumatra. The geochemical fraction was obtained based on the SEP BCR (Sequential Extraction Process Bureau Reference of the European Commission) multilevel procedure in four phases: acid dissolved fraction, reduced fraction, oxidation fraction, and residual fraction. The total metal determination was based on the USEPA 3050B method. Metal concentration determination were carried out using atomic absorption spectrophotometry (AAS). The results showed that anthropogenic activities suspected of contributing Fe metal to sediment were higher indicated by non-residual concentrations (5.55-203.15 mg/kg) than the residual fraction (4.89-21.47 mg/kg). In contrast to Cu, the highest association in the sediment is the residual fraction (2.24-8.85 mg/kg). These metal apparently were derived from both natural and anthropogenic sources. Heavy metals in sediments have contributed from natural and anthropogenic sources, Cu is thought to have more natural sources and Fe is thought to originate predominantly from human activities both around the coast and possibly from the land
THE MODEL OF MACRO DEBRIS TRANSPORT BEFORE RECLAMATION AND IN EXISTING CONDITION IN JAKARTA BAY
Get PDFJakarta Bay as one of an area with the densest population in Indonesia became one of the highest contamination level waters in the world includes pollution of debris. Reclamation activities in Jakarta Bay will change the water conditions, and will also affect the distribution of debris at sea. Therefore, this study conducted is to determine the movement of the marine macro debris before and on the condition of the existing reclamation island in the Bay of Jakarta. The method used is simulated by the hydrodynamic model and particle trajectory models using MIKE software. Data needed for the hydrodynamic model, namely wind, tides, bathymetry, and shoreline, while for the trajectory of the particles using a data type of debris, marine macro debris weight, and debris flux. The analysis was performed for hydrodynamic model simulation results and comparison of particle trajectory models. Hydrodynamics simulations indicate if a reclamation island formation does not change significantly in the offshore area, but a simple change in the surface current pattern of the reclamation area, it also causes a decrease in the flow velocity of ± 0.002 to 0.02 m/s at some point. Macro debris particle trajectory simulation shows if after reclamation, macro debris tends to accumulate in the eastern Jakarta Bay in the rainy season (January), as well as in the western and eastern regions during the dry season (July)
THE FUNCTIONS OF COASTAL SWAMP AS A HABITAT FOR THE TROPICAL EEL Anguilla spp. IN CIMANDIRI RIVER ESTUARY, SUKABUMI WEST JAVA
Get PDFRawa pesisir merupakan rawa pasang-surut bagian dari ekosistem estuari. Rawa pesisir di Sungai Cimandiri Kabupaten Sukabumi, Jawa Barat merupakan salah satu ekosistem estuari yang memiliki peran ekologi yang penting untuk kehidupan biota air yang menetap maupun yang bermigrasi seperti ikan sidat. Penelitian ini bertujuan untuk mengkaji fungsi rawa pesisir, biologi populasi sidat dan faktor lingkungan yang berpengaruh terhadap populasi sidat Penelitian dilakukan secara parsial pada September-Oktober 2016, Maret dan Desember 2017 dan January-November 2018. Penangkapan ikan sidat dan pengukuran kualitas air dilakukan pada 4 lokasi terpilih berdasarkan kondisi habitat yang berbeda. Penangkapan ikan sidat dilakukan pada malam hari dengan alat tangkap pancing dan bubu. Sidat yang tertangkap terdiri dari 2 jenis yaitu Anguilla bicolor bicolor (107 individu) dan Anguilla marmorata (4 individu). Panjang total A. bicolor bicolor adalah 15,7-57,0 cm dan berat 5,8-347,2 g dan panjang total A. marmorata adalah 17,0-29,5 cm dan berat 6,9-33,7 g. Pola pertumbuhan sidat (A.bicolor bicolor) di rawa pesisir adalah allometrik negatif, dengan nilai faktor kondisi 0,99-1,03. Sidat di rawa pesisir banyak tertangkap di daerah rawa pesisir yang dalam dan terdapat tumbuhan air. Berdasarkan analisis PCA (Principal Component Analysis), preferensi keberadaan sidat di rawa pesisir dicirikan oleh parameter kedalaman, kecerahan, salinitas, dan kecepatan arus. Rawa pesisir diketahui berfungsi sebagai habitat bagi ikan sidat muda (yellow eel) pada fase estuarine.The coastal swamp is a tidal swamp part of the estuary ecosystem. Coastal swamp on the Cimandiri River, Sukabumi West Java is one of the estuarine ecosystems that have an important ecological role for the lives of sedentary aquatic biota and migratory fish such as eels. The objectives of this study were to determine the population biology of eels and influential environmental factors in the coastal swamp of the Cimandiri River. The study conducted partially in September-October 2016, March and December 2017 and January-November 2018. Eel fishing and water quality measurements were carried out in 4 selected locations based on different habitat conditions. Eel fishing is done at night with fishhooks and traps. There were two species of tropical eel, Anguilla bicolor bicolor (107 individuals) and Anguilla marmorata (4 individuals). The total length of A. bicolor bicolor is 15.7-57.0 cm and weight 5.8-347.2 g. The total length of A. marmorata is 17.0-29.5 cm and weight 6.9-33.7 g. The growth pattern of A. bicolor bicolor in the coastal swamp was negative allometric, with the condition factor values 0.99-1.03. Based on Principal Component Analysis (PCA), the preferences for the presence of eel in coastal swamp are characterized by parameters of depth, transparency, salinity, and water current. From this study, it is known that the coastal swamp has functioned as a habitat for yellow eels in the estuarine phase
BIOLOGICAL ASPECTS AND EXPLOITATION PAPUAN SEERFISH (Scomberomorus multiradiatus Munro, 1964) WITH GILLNET IN MERAUKE WATERS AND ADJACENTS
Get PDFIkan tenggiri Papua (Scomberomorus multiradiatus) adalah ikan endemik Papua yang tertangkap hanya di sekitar perairan Merauke. Pemanfaatan ikan ini oleh masyarakat lokal dengan tingkat produksi mengalami peningkatan dari tahun ke tahun. Dalam pengelolaan populasi ikan tenggiri Papua diperlukan kajian ilmiah tentang aspek biologi dan pemanfaatannya dengan menggunakan jaring insang hanyut. Penelitian dilakukan selama 2 (dua) tahun yaitu Maret - Desember 2017 dan April -Desember 2018 dengan metode survei yang dibantu oleh enumerator secara bulanan. Data komposisi hasil tangkapan jaring insang hanyut dominan ikan demersal karena dioperasikan di perairan dangkal yang menyapu hingga ke dasar. Ikan tenggiri Papua hanya sekitar 6-10% dari total tangkapan dengan struktur ukuran dominan pada 40 cmFL (fork length) dan pola pertumbuhan allometrik positif. Nisbah kelamin ikan tidak seimbang dengan dominan jantan dibandingkan betina. Ukuran ikan yang pertama kali tertangkap semakin kecil ukurannya yaitu 32.08 (2017) menjadi 30.50 (2018) yang dapat menjadi indikasi bahwa ukuran ikan semakin kecil. Laju pertumbuhan (K) sekitar 0.64 yang menunjukkan laju pertumbuhan tergolong lambat dengan laju kematian akibat penangkapan (F) lebih tinggi dibandingkan kematian alamiah (M). Pemanfaatan ikan ini sudah mencapai E=0,70 atau 140% sehingga harus dilakukan pengurangan 40% dari upaya saat ini dan dengan mengembangkan kearifan lokal agar ikan endemik terjaga populasinya.Papuan mackerel (Scomberomorus multiradiatus) is a Papua endemic fish caught only in Merauke waters and adjacents. The exploitation of this fish by local people with the level of production has increased from year to year. In the management of Papuan mackerel fish populations, scientific studies are needed about biological aspects and their use by drifting gillnets. The study was conducted for 2 (two) years, March - December 2017 and April - December 2018 with survey methods assisted by enumerators monthly. Data on the composition of the catch of the gillnet drift dominantly demersal fish because it is operated in shallow waters that sweep to the bottom. Papuan mackerel is only about 6-10% of the total catch with a dominant size structure at 40 cm FL (fork length) and allometric positive growth pattern. The sex ratio of the fish is unbalanced with the male dominant compared to the female. The size of the first fish caught is getting smaller in size, namely 32.08 (2017) to 30.50 (2018) which can be an indication that the fish size is getting smaller. The growth rate (K) is around 0.64 which shows that the growth rate is relatively slow with the rate of death due to capture (F) higher than natural death (M). The exploitation of this fish has reached E = 0.70 or 140%, so a 40% reduction must be made from the current effort and by developing local wisdom so that the endemic fish population is maintained
WAVEFORM RETRACKING ANALYSES OF ALTIMETRY SATELLITE DATA AROUND GULF, SMALL ISLANDS, AND DEEP WATERS IN HALMAHERA SEA
Get PDFAkurasi estimasi tinggi muka laut (SSH) dari satelit altimeter sangat dipengaruhi oleh kondisi perairan dan daratan disekitar perairan tersebut. Estimasi SSH di laut lepas umumnya sudah akurat. Namun, pada daerah pantai, estimasi SSH kurang akurat karena gangguan pantulan sinyal dari daratan. Penelitian ini bertujuan untuk melakukan analisis retracking waveform satelit altimeter pada perairan yang kompleks di Laut Halmahera. Data yang digunakan pada penelitian ini yaitu data waveform dari Sensor Geophysical Data Record type D (SGDR-D) Jason-2 dan Jason-3 tahun 2017. Algoritma retracking yang digunakan yaitu Offset Centre of Gravity (OCOG), Iced, Threshold, dan Improved Threshold. Hasil retracking waveform menunjukkan semua retracker memberikan perbaikan data SSH yang signifikan kecuali OCOG. Retracker yang paling cocok diaplikasikan di Laut Halmahera pada teluk dangkal dan sempit yaitu Threshold 10%, pada teluk dalam dan lebar yaitu Threshold 50%, serta pada perairan dekat pulau pulau kecil yaitu Threshold 10% dan Threshold 20%. Secara umum, Non-Brown waveform lebih banyak ditemukan di perairan teluk dangkal dan sempit (rata-rata=63,49%) dibandingkan dengan teluk dalam dan lebar (rata-rata=11,51%) dan perairan pulau-pulau kecil (rata-rata=9,57%). Namun demikian, tingkat perbaikan data SSH di perairan teluk dangkal dan sempit lebih tinggi dibandingkan dengan teluk dalam dan lebar serta perairan pulau-pulau kecil dan laut dalam. Persentase peningkatan perbaikan data (IMP) tertinggi yaitu 96,71% dengan algoritma Improved Threshold 10% pada Jason-2 pass 164.The accuracy of sea surface height (SSH) estimation from altimeter satellites is strongly influenced by waters condition and coastal land. In general, SSH estimations in offshore are accurate. However, in coastal waters, SSH estimation are inaccurate due to the reflection of signal from land. The study purpose was to retrack the waveform of Altimeter satellites in a complex the Halmahera Sea. The data used for this study were the waveform Sensor Geophysical Data Record type D (SGDR-D) of Jason-2 and Jason-3 of 2017. To retrack waveform, we used several algorithms i.e., Offset Centre of Gravity (OCOG), Iced, Threshold, and Improved Threshold. All retrackers provided significant improvement in SSH estimations except OCOG. The best retracker used in Halmahera Sea for the shallow and narrow bay was Threshold 10%, for the deep and wide bay was Threshold 50%, and for small islands waters were Threshold 10% and Threshold 20%. In general, Non-Brown waveforms were more common in the shallow and narrow bay waters (average=63.49%) vs. the deep and wide bay waters (average=11.51%) and small island waters (average=9.57%). However, the improvement percentage of SSH estimations in the shallow and narrow bay waters was higher than the deep and wide bay waters and small islands waters. The best retrackers in the Halmahera Sea was the Threshold 10% algorithm with the IMP value of 96.71% on Jason-2 pass 164
STATISTICAL ASSESSMENT OF SEDIMENT GRAIN SIZE AND ITS RELATION WITH SEASONAL AND ANNUAL CLIMATE VARIABILITY IN MUARA GEMBONG, JAKARTA BAY
Get PDFVariabilitas iklim dapat mempengaruhi sifat sedimen yang terendapkan di dasar laut. Salah satu sifat sedimen yang dipengaruhi oleh iklim adalah besar butir. Penelitian ini bertujuan untuk menguji hubungan antara besar butir dengan variabilitas iklim menggunakan sampel core GM01-2010-TJ22 dari Muara Gembong, Teluk Jakarta, muara sungai Citarum. Sampel core diambil pada tahun 2010 dengan menggunakan Kapal Riset Geomarin I oleh Pusat Penelitian dan Pengembangan Geologi Kelautan (P3GL). Pengukuran besar butir dilakukan dengan menggunakan Mastersizer 2000. Hasil pengukuran ditampilkan dalam seri waktu dari tahun 2001 sampai 2010. Hasil analisis besar butir sampel sedimen dikorelasikan secara statistik dengan fenomena musiman (monsun), tahunan dan antar tahun (El Niño/La Niña dan Dipole Mode). Verifikasi data dilakukan dengan menggunakan data sekunder temperatur permukaan laut dari citra satelit di sekitar lokasi sampel dan data curah hujan di Bekasi. Hasil verifikasi menunjukkan bahwa peningkatan curah hujan di sekitar daerah hilir Sungai Citarum diikuti dengan penurunan temperatur permukaan laut dan peningkatan ukuran rata-rata besar butir. Hasil yang didapat dalam uji statistika menunjukkan bahwa perubahan ukuran besar butir sampel sedimen di Muara Gembong memiliki korelasi signifikan dengan Multivariate ENSO (El Niño Southern Oscillation) Index (MEI), Ocean Niño Index (ONI), Dipole Mode Index (DMI) dan Australian Monsoon Index (AUSMI). Hasil tersebut menunjukkan bahwa besar butir sedimen dasar laut potensial digunakan untuk mengetahui variabilitas iklim di sekitar Teluk Jakarta.Climate variability affects the properties of marine sediments. One of the sediment properties affected by climate is the grain size. This study is aimed to test the relation between sediment grain size and climate variability using sediment core GM01-2010-TJ22 that was acquired off Muara Gembong, which is part of Citarum river mouth. The samples were acquired in 2010 onboard RV. Geomarin I by Marine Geological Institute (MGI). Grain size analysis was conducted by Mastersizer 2000. The mean grain size is presented in time series for the 2001-2010 period. Then, the grain size sediment sample was correlated statistically with the seasonal (monsoon), annual, and interannual (El Niño/La Niña and Dipole Mode) phenomena. Data verification was conducted using secondary data of sea surface temperature from satellite images near the sediment sampling location and rainfall data in Bekasi. The verification result shows an increase in precipitation rate downriver of Citarum River followed by the decrease of sea surface temperature and larger grain size. The results using statistical test show that change of sediment sample`s grain size in Muara Gembong have significant correlation with Multivariate of ENSO (El Niño Southern Oscillation) Index (MEI), Ocean Niño Index (ONI), Dipole Mode Index (DMI) and Australian Monsoon Index (AUSMI). This result shows that sediment grain size can potentially be used to identify climate variability in Jakarta Bay
CHEMICAL, MICROBIOLOGY CHANGES AND DETECTION OF HDC GENE ON LONGTAIL TUNA Thunnus tonggol DURING CHILLING TEMPERATURE STORAGE
Get PDFHistamin merupakan senyawa amin biologis yang dapat terbentuk dari histidin bebas dalam daging ikan pada fase post rigor. Laju pertumbuhan histamin dapat diperlambat dengan cara menjaga mutu ikan menggunakan suhu dingin. Tujuan dari penelitian ini adalah menentukan lama waktu penyimpanan, perubahan kimia dan mikrobiologis ikan tongkol Thunnus tonggol serta waktu terdeteksinya gen hdc selama penyimpanan suhu 8±3°C. Rancangan penelitian yang digunakan adalah rancangan acak lengkap (RAL) dengan parameter perbedaan waktu penyimpanan ikan (1,2,3,4,5,6,7 hari) dan perbandingan es 1:1. Hasil penelitian menunjukkan ikan tongkol abu-abu mengalami kemunduran mutu selama 7 hari penyimpanan. Nilai organoleptik dan pH mengalami penurunan selama penyimpanan dan pada hari ketujuh ikan berada pada fase rigormortis. Nilai TVB dan TPC meningkat selama penyimpanan dan pada penyimpanan hari keenam sudah melewati batas aman untuk dikonsumsi. Kadar histamin pada hari ketujuh yaitu 1,96 ppm. DNA berhasil di-isolasi dan terdeteksi gen hdc, namun hasil amplifikasi belum efektif, sehingga diperlukan optimalisasi metode PCR. Profil protein yang terbentuk selama penyimpanan berdasarkan hasil SDS-PAGE mulai terpisah karena adanya aktivitas enzim katepsin.Histamine is a biogenic amine that appear during post moterm phase on the fish flesh that contain high content of histidine. The higher level of histamine can be reduced by good handling practice to maintain fish quality for example: using chilling temperature. This research aimed to determine chemical and microbiology changes from longtail tuna Thunnus tonggol and the time when hdc gene can be detected during chilling temperature storage 8±3°C. This research design was a completely randomized design (CRD) with parameters of differences in fish storage time (1,2,3,4,5,6,7 days) and ice ratio 1:1. The results showed that the tuna fish experienced quality deterioration for 7 days of storage. Organoleptic values and pH decreased during storage and on the seventh day the fish were in the rigormortis phase. TVB and TPC values increased during storage and on the sixth day storage has passed the safe limit for consumption. Histamine levels of this tuna on the seventh day were 1.96 ppm. HDc gene detection using the PCR method showed negative results in each treatment. The protein profile that was formed during storage displayed to separate because of the cathepsin activity
SPATIAL DISTRIBUTION OF CARBON DIOXIDE FLUXES IN KARIMUNJAWA WATERS, INDONESIA
Get PDFPemanasan global terjadi akibat komposisi gas rumah kaca diatmosfer berubah dimana komposisi terbesar didominasi oleh gas karbon dioksida antropogenik. Keadaaan tersebut menimbulkan perubahan iklim di bumi. Oleh karena itu diperlukan serapan gas karbon dioksida yang ada di atmosfer salah satunya melalui lautan yang disebut blue carbon. Tujuan penelitian ini adalah untuk mengetahui potensi serapan blue carbon (Fluks CO2) di perairan Karimunjawa. Penelitian ini dilakukan di perairan sekeliling Pulau Karimunjawa pada bulan Mei 2018. Metode penelitian yang digunakan yaitu metode survei dengan pendekatan kuantitatif. Sampel diambil di 15 stasiun pengamatan perairan Pulau Karimunjawa menggunakan metode purposive sampling method. Variabel yang digunakan yaitu sistem karbonat terdiri dari alkalinitas total, pH, DIC (Dissolved Inorganic Carbon), tekanan parsial CO2 serta kualitas perairan terdiri dari salinitas dan suhu perairan. Analisis data sistem karbonat dengan metode titrimetri. Hasil penelitian menunjukkan bahwa perairan Karimunjawa sebagian besar (13 stasiun) berfungsi sebagai pelepas CO2 dengan kisaran nilai fluks CO2 antara 1,79 sampai 21,64 mmolCO2/m2/hari dimana aliran CO2 bergerak dari lautan ke atmosfer. Sedangkan 2 stasiun lainnya berfungsi sebagai penyerap CO2 dimana aliran CO2 bergerak dari atmosfer ke lautan dengan kisaran nilai fluks CO2 -3,69 sampai -4,41 mmolCO2/m2/hari. Pola fluks CO2 mengikuti pola perubahan ∆pCO2, DIC, total alkalinitas, salinitas dan pH. Secara umum distribusi spasial potensi serapan blue carbon (fluks CO2) di perairan Karimunajwa sebagai pelepas CO2 dari lautan ke atmosfer dengan nilai fluks CO2 positif. Global warming phenomena occures as result of the increase of the amount of greenhouse gases in the atmosphere which is dominated by anthropogenic CO2 (carbon dioxide). These conditions cause climate change on the earth. Therefore, the absorption of carbon dioxide gas in the atmosphere is needed, one of which is through an ocean processes called blue carbon. The purpose of this study was to determine the potential of blue carbon absorption (fluxes CO2) in Karimunjawa waters. This research was conducted in the waters around Karimunjawa Island in May 2018. The research method used a survey method with a quantitative approach. Samples were taken at 15 observation stations of Karimunjawa Island using purposive sampling method. Analysis of carbonate system data by titrimetric method. The results showed that most of Karimunjawa waters (13 stations) functioned as source of CO2 with a range of CO2 flux values between 1.79 to 21.64 mmolCO2/m2/day where the flow of CO2 moved from the ocean to the atmosphere. While the other 2 stations function as sink of CO2 where the flow of CO2 moved from the atmosphere to the ocean with a range of CO2 fluxes of -3.69 to -4.41 mmolCO2/m2/day. The pattern of CO2 fluxes followed a pattern of ∆pCO2, DIC, total alkalinity, salinity, pH. The CO2 flux pattern follows the pattern of changes in ∆pCO2, DIC, total alkalinity, salinity and pH. The spatial distribution of potential blue carbon uptake (fluxes CO2) in Karimunajwa waters as a release of CO2 from the oceans into the atmosphere with a positive flux CO2 value