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Mencakup Penulisan yang berhubungan dengan pelaksanaan penelitian yang dilakukan secara mandiri, atau kelompok, dan berdasarkan Ruang Lingkup Pengelolaan Wilayah Pesisir, Konservasi, Ekowisata, dan Keanekaragaman Hayati Perairan.
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Articles 488 Documents
Granulometric and Bioindex Analysis of Macrobenthos in Malalayang Coastal Waters Windarto, Firmansyah Candra; Rampengan, Royke M.; Windarto, Agung B.; Djamaluddin, Rignolda; Manengkey, Hermanto W.K.; Manu, Gaspar D.
Jurnal Ilmiah Platax Vol. 10 No. 1 (2022): ISSUE JANUARY-JUNE 2022
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35800/jip.v10i1.38817

Abstract

 The purpose of this study was (1) to describe macrozoobenthos and calculate and analyze bio-indexes including density, diversity, domination, and proprietary macrozoobenthos genus found on the beach of Malalayang. (2) inform the condition of habitat sediment granulometry and related to various macrozoobenthos bio-indexes found on the Malalayang Beach. The results of the identification of macrozoobenthos types obtained from the entire research station have obtained macrozoobenthos taxa covering 3 classes, namely: Gastropoda classes include 5 genera, namely Melanella, Margarites, Frigidoalvania, Oenopot, and Cylichna, Crustacean class (2 genera: Pagurus and Hemigrapsus) and Polychaeta classes ( 1 genus: nais). Macrozoobenthos density at Station 1 and Station 3. Overall, station 1 has the highest average density of 29.33 ind./m2; Furthermore, Station 3 has an average density of 23 indv. /m2; And finally Station 2 with a density of 17.67 Ind. /m2. Based on the results of the test, it was concluded that none of the values of the macrozoobenthos diversity index at the research site showed that the H1 acceptance or can be said that the results of the t-test stated that all the recatient research tests were not significantly different meaning the diversity of the entire station tested had the same diversity. The dominance index also obtains values that indicate the condition of the lack of dominance from certain macrozoobenthos genera at the research location.The volume index is obtained that the community is in a stable condition only found at Station 3, namely the rear graduation area in the Malalayang River estuary. Communities that are in depressed conditions are found in the graduation land of station 1 and station 3, as well as the rearstal land of station 2. Other areas obtained by the community are in unstable conditionsThe sediment composition that looks for files to stations at the research site displays diverse conditions. In general, through the graph of the sediment composition produced, at station 1 can be said to have decreased grain size towards land. Physical at Station 2, on the contrary, experienced an increase in a more rough (gravel) sediment on the middle and rear land, and at station 3, the center of the center looks composed of sediments that have a rough size.Keywords: intertidal; macrobenthos; sediment AbstrakTujuan penelitian ini adalah (1) Mendeskripsikan makrozoobenthos serta menghitung dan menganalisis bioindeks meliputi kepadatan, keanekaragaman, dominasi, dan kemerataan genus makrozoobenthos yang terdapat di Pantai Malalayang. (2) Menginformasikan kondisi granulometri sedimen habitat dan kaitannya dengan berbagai bioindeks makrozoobenthos yang terdapat di pantai Malalayang. Hasil identifikasi jenis-jenis makrozoobenthos yang diperoleh dari keseluruhan stasiun penelitian telah diperoleh taksa makrozoobenthos meliputi 3 kelas yaitu: Kelas Gastropoda meliputi 5 Genera yakni Melanella, Margarites, Frigidoalvania, Oenopotadan Cylichna, Kelas Crustacea (2 Genus: Pagurus dan Hemigrapsus) dan Kelas Polychaeta (1 Genus: Nais).Kepadatan makrozoobenthos pada Stasiun 1 dan Stasiun 3,  Secara keseluruhan, Stasiun 1 memiliki rata-rata kepadatan tertinggi yaitu sebesar 29,33 ind./m2; selanjutnya Stasiun 3 memiliki kepadatan rata-rata 23 ind./m2; dan terakhir Stasiun 2 dengan kepadatan 17,67 ind./m2.Berdasarkan hasil uji_t diperoleh kesimpulan bahwa tidak ada satupun dari nilai indeks keanekaragaman makrozoobenthos pada lokasi penelitian menunjukkan terima H1 atau dapat dikatakan hasil uji-t menyatakan bawha semua satisun penelitian yang di uji tidak berbeda nyata artinya keanekaragaman seluruh stasiun yang diuji mempunyai keanekaragaman sama. Indeks Dominansi juga memperoleh nilai-nilai yang menunjukkan kondisi tidak adanya dominasi dari genus makrozoobenthos tertentu pada lokasi penelitian.Indeks kemerataan diperoleh bahwa komunitas berada dalam kondisi stabil hanya terdapat pada Stasiun 3, yaitu area lahan gisik bagian belakang di muara Sungai Malalayang.  Komunitas yang berada dalam kondisi tertekan, terdapat pada lahan gisik bagian depan Stasiun 1 dan Stasiun 3, serta lahan gisik bagian belakang Stasiun 2.  Area lainnya diperoleh komunitas berada dalam kondisi yang labilKomposisi sedimen yang menghampari gisik pada stasiun-stasiun di lokasi penelitian menampilkan kondisi yang beragam.  Secara umum, melalui grafik komposisi sedimen yang dihasilkan, pada Stasiun 1 dapat dikatakan terjadi penurunan ukuran butir ke arah darat. Gisik pada Stasiun 2, sebaliknya mengalami peningkatan sedimen berukuran lebih kasar (kerikil) pada lahan bagian tengah dan belakang, dan pada Stasiun 3, gisik bagian tengah tampak tersusun oleh sedimen yang memiliki ukuran kasar. Kata Kunci: intertidal; makrobenthos; sedimen
Distribution and Diversity of Ascidian in Manado Bay, North Sulawesi Leleran, Andreas J. P. L.; Pratasik, Silvester B.; Salaki, Meiske S.; Lumingas, Lawrence J. L.; Kambey, Alex D.; Undap, Suzanne L.
Jurnal Ilmiah Platax Vol. 10 No. 1 (2022): ISSUE JANUARY-JUNE 2022
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35800/jip.v10i1.38842

Abstract

The purpose of this study was to determine the distribution and the diversity of ascidians in Manado Bay including species composition, density, diversity, and dominance. This study used the quadrat transect method. This study found differences in the number of ascidian species with water depth, 11 species of 5 families at 15 M depth, and 8 species of 3 families at 7 M depth. The diversity index ranged from 0.868 to 1.844 at 15 M depth and 0.965 to 1.864 at 7 M depth, the evenness index was 0.533 – 0.839 at 15 M depth and 0.600 – 0.897 at 7 M depth, the dominance index was 0.254 – 0.745 at 15 M depth and 0.254 – 0.708 at 7 M depth. Ascidian in Manado Bay had two distribution patterns, a uniform distribution pattern and a clustered distribution pattern. Environmental parameters had a water temperature of 27 oC – 31 oC, the salinity of 30 0/00 – 32 0/00, the brightness of 12 m – 14 m, and pH of 8 – 10.*Keywords: Ascidian; diversity; ecological index; distribution patternAbstrakTujuan dari penelitian ini adalah untuk mengetahui distribusi dan keanekaragaman jenis ascidia di perairan Teluk Manado meliputi: komposisi jenis, kepadatan individu, keanekaragaman, dan dominansi. Serta mengetahui pola distribusi ascidia. Penelitian ini menggunakan metode transek kuadran. Pada penelitian ini ditemukan perbedaan jumlah spesies ascidia menurut kedalaman, 11 spesies dari 5 family pada 15 M dan 8 spesies dari 3 famili pada kedalaman 7 m. Nilai indeks keanekaragaman ascidia di kedalaman 15 m = 0.868 – 1.844 dan 7 m = 0.965 - 1.864, indeks keseragaman 15 m = 0.533 – 0.839 dan 7 m = 0.600 – 0.897, indeks Dominasi15 m = 0.254 – 0.745 dan 7 m = 0.254 – 0.708. Ascdia di perairan Teluk Manado memiliki dua pola distribusi yaitu pola distribusi seragam dan pola distribusi mengelopok. Parameter lingkungan memiliki suhu air 27 oC – 31 oC, salinitas 30 0/00 – 32 0/00, kecerahan 12 m – 14 m, dan pH 8 – 10.*Kata kunci : Ascidia; keanekaragaman; indeks ekologi; pola distribusi
Evaluation of 16S rRNA Gene Sequence for DNA Barcoding of Tuna Fish Kolondam, Beivy J
Jurnal Ilmiah Platax Vol. 10 No. 1 (2022): ISSUE JANUARY-JUNE 2022
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35800/jip.v10i1.38861

Abstract

For fish product authentication, DNA barcoding has been a reliable tool. This is due to its requirement of a small amount of tissue sample in order to conduct a full analysis for species identification. This research aimed to conduct an assessment for the use of 16S rRNA gene sequence for tuna fish identification through DNA barcoding. Previous in silico studies using the COI gene and CYB gene were conducted using the same tuna fish specimens. A comparison of 16S rRNA gene sequence between Bluefin tuna (five species), Yellowfin tuna (three species), and another group of tuna (five species) showed the reliability of this gene in differentiating all species represented by the respective specimens. The multiple sequence alignment of 1695 bp in this research is reliable for accurate identification. All specimens of Thunnus (Bluefin group and Yellowfin group) were able to be differentiated with other genera (Auxis, Euthynnus, and Katsuwonus) group in 27 sites. The other tuna fish genera group members are similar in 27 sites and the member Thunnus group has a polymorphism in the same location. The similarity among the Bluefin group is 99.3% to 99.8%. The similarity among Yellowfin group is 99.6% to 99.9%. The similarity among the other group is 97.5% to 99.5%. In conclusion, the 16S rRNA gene is a reliable marker for DNA barcoding of tuna fish.Keywords: DNA barcoding; 16S rRNA gene; tuna fishAbstrakUntuk kepentingan autentikasi produk-produk dari ikan, DNA barcoding merupakan perangkat yang dapat diandalkan. Ini disebabkan karena metode ini hanya membutuhkan sedikit sampel jaringan untuk analisis identifikasi spesies. Penelitian ini bertujuan untuk melakukan asesmen penggunaan sekuens gen 16S rRNA untuk identifikasi ikan tuna melalui DNA barcoding. Studi in silico sebelumnya untuk gen COI dan gen CYB dilaksanakan menggunakan spesimen ikan tuna yang sama. Perbandingan sekuens gen 16S rRNA antara kelompok ikan tuna Bluefin (lima spesies), kelompok ikan tuna Yellowfin (tiga spesies), dan kelompok ikan tuna jenis lain (lima spesies) menunjukkan kemampuan gen ini dalam membedakan semua spesies. Dari hasil yang diperoleh, penjajaran multisekuens dari 1695 bp dapat diandalkan untuk indentifikasi yang akurat. Semua spesimen genus Thunnus (kelompok Bluefin dan kelompok Yellowfin) dapat dibedakan dengan spesimen lainnya pada 27 titik nukleotida. Kelompok tuna jenis lain juga memiliki nukleotida yang seragam di 27 lokasi dibandingkan dengan yang dari genus Thunnus. Tingkat kesamaan antar spesimen kelompok tuna Bluefin yaitu 99,3% sampai 99,8%. Tingkat kesamaan antar spesimen kelompok tuna Yellowfin yaitu 99,6% sampai 99,9%. Tingkat kesamaan antar kelompok tuna jenis lain yaitu 97,5% sampai 99,5%. Dari penelitian ini dapat disimpulkan bahwa gen 16S rRNA merupakan gen yang dapat diandalkan untuk DNA barcoding ikan tuna.Kata-kata kunci: DNA barcoding; gen 16S rRNA; ikan tuna
Polychaeta Communities in Subtidal Zone Soft Substrate of Manado Bay, North Sulawesi Lumingas, Aaron R. T.; Boneka, Farnis B.; Ompi, Medy; Mamangkey, Noldy G. F.; Manembu, Indri S.; Undap, Suzanne L.; Lumingas, Lawrence J. L.
Jurnal Ilmiah Platax Vol. 10 No. 1 (2022): ISSUE JANUARY-JUNE 2022
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35800/jip.v10i1.39518

Abstract

This study aims to analyze the structure of the Polychaeta community on the soft substrate of the subtidal zone in Manado Bay. Samples were taken by grab at 3 stations namely ST1 located at a depth of 8 m with black mud substrate; ST2 is located at a depth of 26 m with blackish sand substrate, and ST3 are located at a depth of 18 m with blackish sand as a substrate. From the three sampling stations, 27 species of 253 Polychaeta individuals were identified. Station 1, which is located near the mouth of the Bailang River, has high individual abundance but low species diversity. Station 2, which is located near the Megamas area, has moderate individual abundance but high species richness. Station 3, which is located around the Faculty of Medicine, Unsrat Malalayang, has low individual abundance but high species richness. Substrate types and anthropogenic disturbances such as enrichment of organic matter are thought to be determinants of individual abundance, composition, and species richness of Polychaeta in Manado Bay.Keywords: Polychaeta; biodiversity; soft substrate; Manado BayAbstrak Penelitian ini bertujuan untuk menganalisis struktur komunitas Polychaeta pada substrat lunak zona subtidal di Teluk Manado. Sampel diambil dengan grab pada 3 stasiun yakni ST1 terletak pada kedalaman 8 m dengan substrat lumpur berwarna hitam; ST2 terletak pada kedalaman 26 m dengan substrat pasir berwarna kehitaman; dan ST3 terletak pada kedalaman 18 m dengan substrat pasir berwarna kehitaman. Dari tiga stasiun sampling tersebut berhasil diidentifikasi 27 spesies dari 253 individu Polychaeta. Stasiun 1 yang terletak dekat muara Sungai Bailang memiliki kelimpahan individu tinggi tetapi keanekaragaman spesies rendah. Stasiun 2 yang terletak dekat kawasan Megamas memiliki kelimpahan individu sedang tetapi kekayaan spesies tinggi. Stasiun 3 yang terletak di sekitar pemukiman belakang Fakultas Kedokteran Unsrat Malalayang memiliki kelimpahan individu rendah tetapi kekayaan spesies tinggi. Jenis substrat dan gangguan antropogenik seperti pengayaan bahan organik diduga merupakan faktor penentu kelimpahan individu, komposisi dan kekayaan spesies Polychaeta di Teluk Manado. Kata Kunci: Polychaeta; keanekaragaman hayati; substrat lunak; Teluk Manado
Mapping of Fishing Areas and Fish Catches by Purse Sine KM. Rebert Tinambunan, Deviana; Silooy, Fanny; Luasunaung, Alfret; Labaro, Ivor Lembondorong; Kayadoe, Mariana E; Sitanggang, Effendi Pengihutan; Thamin, arman; Dien, Heffry V
Jurnal Ilmiah Platax Vol. 10 No. 1 (2022): ISSUE JANUARY-JUNE 2022
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35800/jip.v10i1.39694

Abstract

The division of Indonesian waters into several fisheries management areas illustrates very different habitat characteristics and has a diversity of biological resources that may vary. WPPNRI 716 is a management area in Indonesian waters which includes the waters of the Sulawesi Sea and the northern part of Halmahera Island. This research was carried out by the purse seiner KM. Rebert carried out fishing operations in the waters of the Sulawesi Sea at WPPNRI 716. Data collection was carried out for 4 months, namely from October 2021 - to January 2022, with the aim of knowing the distribution area of catching and KM. Rebert catches. KM. Rebet catchment area based on the GPS point is located at WPPNRI 716, which is 81.5 miles from the fishing base (Tumumpa Beach Fishery Port). The number of catches in October (trip 1) was 6350 kg, in October (trip 2) was 4807 kg, in November (trip 3) was 10245 kg, in December (tip 4), was 4234 kg, in December (trip 5) as much as 4280 Kg, in January (trip 6) as many as 2645, and in January (trip 7) 4350 Kg. Judging from the type of catch during the research, there was 13265 kg of mackerel scad (Decapterus sp), then 12953 kg of skipjack tuna (Katsuwonus pelamis L), 4884 kg of yellowfin tuna (Thunnus albacares), and 4100 kg of mackerel tuna (Euthinnus affinis). Selar fish (Selaroides sp) as much as 904 Kg, jackfish (Caranx sp) as much as 500 Kg, rainbow runner fish (Elagatis bipinnulatus) as much as 350 Kg, and the lowest is bullet tuna (Auxis rochei) fish as much as 55 Kg.Keywords: Mapping; KM. Rebert; Purse SeinerAbstrakPembagian wilayah perairan Indonesia ke dalam beberapa kawasan pengelolaan perikanan menggambarkan karakteristik habitat yang sangat berbeda dan memiliki keanekaragaman sumberdaya hayatinya yang dapat saja berbeda. WPPNRI 716 merupakan wilayah pengelolaan di perairan Indonesia yang meliputi perairan Laut Sulawesi dan sebelah Utara Pulau Halmahera.Penelitian ini dilaksanakan kapal pukat cincin (purse seiner) KM. Rebert yang melakukan operasi penangkapan ikan di perairan Laut Sulawesi pada WPPNRI 716.  Pengambilan data dilakukan selama 4 bulan yaitu pada bulan Oktober 2021 - Januari 2022, dengan tujuan untuk mengetahui daerah sebaran penangkapan dan hasil tangkapan KM. Rebert. Daerah penangkapan KM. Rebet berdasarkan titik GPS berada pada WPPNRI 716 yang berjarak dari fishing base (Pelabuhan Perikanan Pantai Tumumpa) ± 81,5 mil. Jumlah hasil tangkapan pada bulan bulan Oktober (trip 1) sebanyak 6350 Kg, bulan Oktober (trip 2) sebanyak 4807 Kg, bulan November (trip 3) sebanyak 10245 Kg, bulan Desember (tip 4), sebanyak 4234 Kg, bulan Desember (trip 5) sebanyak 4280 Kg, bulan Januari (trip 6) sebanyak 2645, dan bulan Januari (trip 7) 4350 Kg. Dilihat dari jenis tangkapan selama penelitan adalah ikan layang (Decapterus sp) sebanyak 13265 Kg, kemudian ikan cakalang (Katsuonus pelamis L) sebanyak 12953 Kg, ikan tuna sirip kuning (Thunnus albacares) sebanyak 4884 Kg, ikan tongkol (Auxis rochei) sebanyak 4100 Kg ikan selar (Selaroides sp) sebanyak 904 Kg, ikan kuwe (Caranx sp) sebanyak 500 Kg, ikan sunglir (Elagatis bipinnulatus) sebanyak 350 Kg, dan yang paling rendah adalah ikan tongkol (Auxis rochei) sebanyak 55 Kg.Kata Kunci:Pemetaan; KM. Rebert; Pukat Cincin. 
Length Weight Relationship of Bigeye Scad (Selar crumenophthalmus) Catch by Purse Seine in Manado Bay Makarondong, Geral Manuel; Sitanggang, Effendi P.; Labaro, Ivor L.; Luasunaung, Alfret; Manoppo, Lefrand; Pangalila, Fransisco P. T.; Thamin, Arman
Jurnal Ilmiah Platax Vol. 10 No. 1 (2022): ISSUE JANUARY-JUNE 2022
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35800/jip.v10i1.39718

Abstract

The intensity of the catch of bigeye scad (Selar crumenophthalmus), is expected to cause problems in the availability of these fish resources. The purpose of this research is to analyze the Length-weight relationship of Bigeye scad caught by purse seine in Manado Bay. as well as to evaluate the results of the analysis of the Length-weight relationship and the catchment feasibility of the catch to support the sustainability of the potential of bigeye scad resources. The method used in this study is a quantitative method. conducted at Tumumpa Manado Coastal Fisheries Port, using fork length measurement data (FL) and weight of bigeye scad taken by the author under the guidance of lecturers in May 2021 and November 2021. Length-weight relationship of bigeye scad caught in May 2021 follows the equation W = 0,0249 L2.8057 with K = 1.01 and in November 2021 W = 0,0207 L2.9151. The type of bigeye scad in both seasons is categorized as negative allometric. This fish is categorized as unfit to catch (Lc < Lm). The structure of the catch in May 2021 obtained an average length of 10.26 ± 0.26 cm and an average weight of 18.03 ± 1.51 g where 51% were caught at a size of 9.8-10.8 cm and 46% had a weight of 11.0-16.0 g. while in November 2021 the average length was 10.90 ± 0.28 cm and the average weight was 22.53 ± 1.76 g where 50% were caught at a size of 10.0-11.0 cm and 31% g weight 21.0-26.0 g.Keywords: Bigeye Scad; Length Weight Relationship; Decent Catch; Purse Sein; Manado BayAbstrakIkan Selar bentong memiliki cita rasa enak, disukai masyarakat, dan harganya pun murah. Intensitas ketertangkapan jenis ikan ini, diduga kelak akan menimbulkan masalah ketersediaan sumberdaya ikan ini. Tujuan penelitian ini menganalisis hubungan panjang berat ikan selar bentong hasil tangkapan kapal pukat cincin (purse seiners) di Teluk Manado, serta Mengevaluasi hasil analisis hubungan panjang berat ikan selar bentong dengan kelayakan tangkap hasil tangkapan untuk menopang keberlanjutan potensi sumberdaya ikan selar bentong ini. Metode yang digunakan pada penelitian ini yaitu metode kuantitatif, dilakukan di Pelabuhan Perikanan Pantai (PPP) Tumumpa Manado, dengan menggunakan data ukuran panjang cagak (fork length, FL) dan berat ikan selar bentong yang diambil oleh penulis di bawah bimbingan dosen pada Mei 2021 (musim Pancaroba I) dan November 2021 (musim Pancaroba II) yang tertangkap purse seiners di Teluk Manado. Hubungan panjang berat ikan selar bentong yang tertangkap pada Mei 2021 mengikuti persamaan W = 0,0249 L2.8057 dengan K = 1.01 dan pada November 2021 W = 0,0207 L2.9151. Tipe pertumbuhan ikan selar bentong pada kedua musim tersebut terkategori alometrik negatif (b < 3), ikan ini terkategori tidak layak tangkap (Lc < Lm). Struktur hasil tangkapan pada Mei 2021 diperoleh panjang rerata 10.26 ± 0.26 cm dan berat rerata 18.03 ± 1.51 g, di mana 51% tertangkap pada ukuran 9.8 - 10.8 cm dan 46% memiliki berat 11.0-16.0 g, sementara pada November 2021 panjang rerata 10.90 ± 0.28 cm dan berat rerata 22.53 ± 1.76 g, di mana 50% tertangkap pada ukuran 10.0-11.0 cm dan 31% memiliki berat 21.0-26.0 g.  Kata Kunci: Selar Bentong; Hubungan Berat Panjang; Kelayakan Tangkap; Pukat Cincin; Teluk Manado
Application of The Admiralty Method to Process Tidal Data in the Waters of The Nasik Strait - Bangka Belitung Pasaribu, Roberto Patar; Sewiko, Roni; Arifin, Arifin
Jurnal Ilmiah Platax Vol. 10 No. 1 (2022): ISSUE JANUARY-JUNE 2022
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35800/jip.v10i1.39719

Abstract

Tides are the rise and fall of sea level caused by the attraction of objects in the sky, especially the moon and sun, to the mass of seawater on earth. Tidal research is useful for providing information about the components and types of tides and predicting tides and for mitigating natural disasters. Tidal measurements were carried out in the Nasik Strait, Bangka Belitung using the Valeport 106 tool. Tidal data was processed using the Admiralty Method. The Admiralty method is a method used to calculate tidal harmonic constants from observations of water levels. With this method, it is possible to know the amplitude and phase difference of the tides, the value of the Formzahl number, and the type of tide. From the results of data processing and analysis, the value of the Formzahl number in the waters of the Nasik Strait is 11,454 and the tidal type is a single daily tidal type that only occurs at one high tide and one low tide in one day.Keywords: tides; tidal types; admiralty method; formzahl numberAbstrakPasang surut adalah naik turunnya muka air laut yang disebabkan oleh gaya tarik benda-benda di langit, terutama bulan dan matahari terhadap massa air laut yang ada di bumi. Penelitian pasang surut bermanfaat untuk memberikan informasi mengenai komponen dan tipe pasang surut serta  memprediksi pasang surut serta untuk mitigasi bencana alam. Pengukuran pasang surut dilakukan di Perairan Selat Nasik, Bangka Belitung dengan menggunakan alat Valeport 106. Data pasang surut diolah dengan menggunakan Metode Admiralty. Metoda Admiralty merupakan metode yang digunakan menghitung konstanta harmonik pasang surut dari pengamatan ketinggian air. Dengan metoda ini dapat diketahui  amplitudo dan beda fase pasang surut, nilai bilangan Formzahl dan tipe pasang surutnya. Dari hasil pengolahan dan analisa data diperoleh nilai bilangan Formzahl di perairan Selat Nasik yaitu 11,454 dan tipe pasang surut adalah tipe pasang surut harian tunggal yang hanya terjadi satu kali pasang dan satu kali surut dalam satu hari.Kata Kunci: pasang surut; tipe pasang surut; metode admiralty; bilangan formzahl
Dissolved Oxygen in the East Bolaang Mongondow Waters, North Sulawesi Patty, Simon I.; Rizqi, Marenda Pandu; Huwae, Rikardo
Jurnal Ilmiah Platax Vol. 10 No. 1 (2022): ISSUE JANUARY-JUNE 2022
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35800/jip.v10i1.40434

Abstract

Oxygen in seawater comes from the air through diffusion and photosynthesis. This study aims to determine the dissolved oxygen content, NAEC (Normal Atmospheric Equilibrium Concentration), and AOU (Apparent Oxygen Utilization) in East Bolaang Mongondow waters. The analysis showed that the dissolved oxygen content in the surface layer ranged from 6.01-7.05 mg/l; 5.91-6.98 mg/l (5 m depth); and 5.75-6.90 mg/l (near bottom depth). NAEC is closely related to water temperature and implicitly increases with depth. The highest NAEC value of 5.90 mg/l (t=28.0ºC) was found at the bottom depth, and the lowest NAEC of 5.63 mg/l (t=30.0ºC) was found at the surface layer. The dissolved oxygen saturation level of more than 100% and the average positive AOU value at 0.59-0.81 mg/l describe the amount of oxygen available in the surface layer.Keywords: Dissolved Oxygen; Normal Atmospheric Equilibrium Concentration (NAEC); Apparent Oxygen Utilization (AOU); East Bolaang Mongondow.AbstrakOksigen dalam air laut bersumber dari udara melalui proses difusi dan hasil fotosintesis. Penelitian ini bertujuan untuk mengetahui kandungan oksigen terlarut, NAEC (normal atmospheric equilibrium concentration) dan AOU (apparent oxygen utilization) di perairan Bolaang Mongondow Timur. Hasil analisis menunjukkan bahwa kandungan oksigen terlarut di lapisan permukaan berkisar antara 6,01-7,05 mg/l; kedalaman 5 meter 5,91-6,98 mg/l dan dekat dasar 5,75-6,90 mg/l. NAEC sangat berhubungan dengan suhu air dan secara implisit konsentrasinya akan semakin tinggi dengan bertambahnya kedalaman. Nilai NAEC tertinggi 5,90 mg/l (t=28,0ºC) ditemukan pada kedalaman dekat dasar dan  NAEC terendah 5,63 mg/l (t=30,0ºC) ditemukan pada lapisan permukaan. Tingkat kejenuhan oksigen terlarut >100 % dan rata-rata nilai AOU positif (0.59-0.81 mg/l) menggambarkan banyaknya kandungan oksigen yang tersedia pada lapisan permukaan.Kata kunci: oksigen terlarut; normal atmospheric equilibrium concentration (NAEC); apparent oxygen utilization (AOU); Bolaang Mongondow Timur.
Diversity and Abundance of Echinoderms in Pancuran Beach, Lembeh Island Christianti, Yudith; Boneka, Farnis; Kaligis, Erly; Wagey, Billy Th.; Sinjal, Chatrien A. L.; Lasabuda, Ridwan
Jurnal Ilmiah Platax Vol. 11 No. 2 (2023): ISSUE JULY-DECEMBER 2023
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35800/jip.v11i2.47753

Abstract

Echinodermata are found quite commonly in the tidal areas of Lembeh Island but their diversity and abundance have not been well documented. The purpose of this study was to determine the types of Echinoderms and their abundance at Pancuran Beach, Lembeh Island, Bitung City. Samples were taken at two stations using the Lincoln-Smith Transect method 2 x 50 m which was stretched perpendicular to the beach with three replications. Samples were identified in situ and the number of individuals of each species was noted. The results showed that in Pancuran Beach there were 18 species of phylum Echinodermata; with details of 7 species from the Asteroidea class, 5 species of Echinoidea, 4 species of Ophiuroidea, 2 species of Holothuroidea. The results of the analysis using the diversity index show that the diversity of Echinodermata at both stations is in the medium category, characterized by the value of H' = 2.06 for station I and H'= 2.35 for station II.  At station 1, the type of Ophiocoma erinaceus has the highest density of 15 ind/100m2 and a relative abundance of 23.68%. At station II Echinothrix diadema has the highest abundance of 12 ind/100m2 with a relative abundance of 17.14%. Common species found in both stations are Diadema setosum, Echinometra mathaei, Echinothrix diadema, Holothuria atra, Ophiocoma erinaceus, and Ophiocoma scolopendrina. Keywords: Lembeh Island, Diversity, Abundance, Echinoderms Abstrak Echinodermata ditemukan cukup umum di daerah pasang surut Pulau Lembeh namun keanekaragaman dan kelimpahannya belum sepenuhnya didokumentasikan dengan baik. Tujuan penelitian ini adalah untuk mengetahui jenis-jenis Echinodermata dan kelimpahannya di Pantai Pancuran, Pulau Lembeh Kota Bitung. Sampel diambil pada dua stasiun dengan menggunakan metode Lincoln-Smith Transect 2 x 50 m yang dibentangkan tegak lurus ke arah pantai dengan tiga replikasi. Sampel diidentifikasi secara insitu dan jumlah individu tiap spesies dicatat. Hasil menunjukkan bahwa di Pantai Pancuran terdapat 18 spesies filum Echinodermata; dengan rincian 7 spesies dari kelas Asteroidea, 5 spesies Echinoidea, 4 spesies Ophiuroidea, 2 spesies Holothuroidea. Hasil analisa menggunakan indeks keanekaragaman menunjukkan bahwa diversitas Echinodermata pada kedua stasiun dalam kategori sedang, ditandai dengan nilai H' = 2,06 untuk stasiun I dan H'= 2,35 untuk stasiun II.  Pada stasiun 1, jenis Ophiocoma erinaceus paling tinggi densitasnya yakni 15 ind/100m2 dan kelimpahan relatif 23,68%, Pada stasiun II Echinothrix diadema memiliki kelimpahan tertinggi yakni 12 ind/100m2 dengan kelimpahan relatif 17,14%. Jenis yang umum terdapat pada kedua stasiun adalah Diadema setosum, Echinometra mathaei, Echinothrix diadema, Holothuria atra, Ophiocoma erinaceus, dan Ophiocoma scolopendrina. Kata kunci: Pulau Lembeh, Keanekaragaman, Kelimpahan, Echinodermata.
A New and Practical Method for Measuring Sponge Spicules Rieuwpassa, Frets J.; Tomasoa, Aprelia M.; Palawe, Jaka F. P.; Rieuwpassa, Fredrik; Mege, Revolson Alexius; Balansa, Walter
Jurnal Ilmiah Platax Vol. 11 No. 2 (2023): ISSUE JULY-DECEMBER 2023
Publisher : Sam Ratulangi University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35800/jip.v11i2.47882

Abstract

Binocular light microscopy (BLM) is an excellent match for a scanning electron microscope (SEM) and a trinocular light microscope equipped with a micrometer (TLM). The practicality, user-friendliness, and short-time analysis of BLM make this method a good choice for spicule analysis. However, its effectiveness and accuracy are yet to be confirmed. This study aimed to validate the effectiveness of BLM by comparing its usefulness to both TLM and the gold standard methods. BLM was first subjected to measuring megascleres and microscleres of 2 sponges. Then, by using the If function built-in Excell and t-test in SPSS 16.0, the compatibility of BLM was evaluated against SEM by measuring the length of spicules from 4 Sangihe sponges and their counterpart species from different locations. Furthermore, the t-test analysis was used to validate the compatibility and effectiveness of our method to the TLM by measuring the spicules of four sponges. Both the F-function and the t-test analysis proved BLM was compatible with SEM with both measurements showing a perfect match for megascleres typed spicules of 4 compared sponges. This new technique also showed a perfect match with SEM (p = 0.367, t-test) and with TLM (p = 0.963, t-test). Keywords: Spicules, sponges, SEM, Wallacea, biomaterial, sponge taxonomy

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