Ship Maintenance Techniques for Removing Sea Barnacles That Stick to the Ship's Hull

The growth of marine biota such as barnacles attached to ship hulls is one of the main challenges in the shipping industry because it can increase hydrodynamic resistance, fuel consumption and accelerate corrosion of ship structures. This research aims to analyze the effectiveness of various ship maintenance techniques in removing sea barnacles and evaluate the advantages and challenges of each method used. The research method applied is a Systematic Literature Review (SLR) by analyzing previous studies discussing ship maintenance techniques in preventing and eliminating fouling. Data analysis was carried out using NVivo to identify research trends and VOSviewer to map relationships between methods used in previous studies. The research results show that the most effective approach in preventing the growth of barnacles is a combination of several methods, such as the use of silicone or fluorine-based paint which has low adhesion, ultrasonic technology which inhibits the colonization of marine biota, and a robot-based automatic cleaning system which can remove fouling without damaging the structure of the ship. This hybrid approach not only increases the fuel efficiency of ships but also helps reduce the impact of marine pollution due to the use of toxic chemicals. With the development of antifouling technology and the implementation of more innovative maintenance strategies, the shipping industry is expected to increase operational efficiency while supporting the long-term sustainability of the marine environment. Keywords: Ship Treatment, Antifouling, Ultrasonic Technology, Fouling, Hybrid Approach

Study of e-DNA Quality at Fishing Ground of Manado Bay, North Sulawesi Province.

We used the Nansen Bottle Sampler to collect water samples in the deepsea area, ranging from 150 meters to 175 meters in six water points around Manado Bay, to test the quality of e-DNA water samples to detect target species in the fishing area. Therefore, the basis of the case study method with a sampling technique was carried out on July 29 2023 using Power Water Sterivex Kits, water samples were then stored at -250C and were then taken to TBRC, University of the Ryukyus for further laboratory works, such as; eDNA extract, eDNA quality testing, 1st and 2nd PCR and Electrophoresis eDNA analysis processes using MiFish-U primers with a target of 163–185bp and 375 bp, following the MiFish protocol.  Based on the results of the eDNA extract solution, it is known that the quality of eDNA from the 6 sampling sites locations ranged between 2.8 µg/mL – 4.4 µ g/mL, which means a good quality of eDNA. Moreover, it showed that the presence of DNA fragments at Kappa 60◦C Gelelectrophoresis 1st-PCR, 12S rRNA gene product (163–185bp), and Kappa 60◦C and 65◦C Geklelectrophoresis 2nd-PCR Products according to the target amplicon 375 bp. This means we can conduct the next step, the PCR sequence analysis.  Then, eDNA quality testing, 1st and 2nd PCR, and Electrophoresis of e-DNA analysis process were using MiFish-U F/R primers with a target of 375 bp, it is known that the concentration of Nanodrop from the 6 sampling locations ranges between 2.8 µg/mL – 4.4 µg/mL while the core or quality eDNA ranged from 1.56 µg/mL – 2.50 µg/mL. Based on identification results, five types of species were detected; Myctophum lychnobium, Selar crumenophthalmus, Photonectes sp., Oreochromis sp. Thunnus obesus and Homo sapiens were generated using eDNA metabarcoding on the mitochondria genome database MitoFish. Keywords: e-DNA, eDNA quality, species target, fishing area, Manado Bay   Abstrak Kami menggunakan Nansen Bottle Sampler untuk mengambil sampel air pada laut dalam berkisar 150meter sampai 175 meter di enam titik perairan Sekitar Teluk Manado, untuk menguji Kualitas e-DNA sample air yang digunakan untuk mendeteksi target spesies pada daerah penangkapan. Selanjutnya dasar metode studi kasus dengan teknik pengambilan sampel secara sampling dilakukan pada tanggal 29 Juli 2023 menggunakan Power Water Sterivex Kits, sapel air disimpan pada -250C yang selanjutnya dibawa ke TBRC, University of the Ryukyus untuk pnelitian laboratorium lanjutan seperti ekstrak eDNA, Pengujian kualitas eDNA, 1st and 2nd PCR dan Elektrophoresis proses analisis eDNA menggunakan primer MiFish-U dengan target 375 bp, mengikuti MiFish protokol. Berdasarkan hasil pengujian larutan ekstrak eDNA diketahui bahwa kualitas eDNA dari 6 titik lokasi sampling berkisar antara 2.8 ng/mL – 4.4 ng/mL dan menunjukkan adanya fragment DNA pada Kappa 60◦C Geklelectrophoresis 1st-PCR Produk 12S rRNA gene (163–185bp, dan Kappa 60◦C dan 65◦C Geklelectrophoresis 2nd-PCR Produk sesuai amplikon target 375 bp. Hal ini berarti dapat dilanjutkan pada tahap analisis sekuens PCR. Pengujian kualitas eDNA, 1st and 2nd PCR dan Elektrophoresis proses analisis eDNA menggunakan primer MiFish-U F/R dengan target 375 bp, diketahui bahwa konsentrasi Nanodrop dari 6 titik lokasi sampling berkisar antara 2.8 µg/mL – 4.4 µg/mL sedangkan kemurnian atau kualitas eDNA berkisar antara 1.56 µg/mL – 2.50 µg/mL. Hasil identifikasi menyatakan lima jenis spesies terdeteksi; Myctophum lychnobium, Selar crumenophthalmus, Photonectes sp., Oreochromis sp. Thunnus obesus, Homo sapiens dihasilkan dengan menggunakan eDNA metabarcoding pada MitoFish database genom mitokondria. Kata kunci : e- DNA, kualitas eDNA, target spesies, daerah penangkapan, Teluk Manado

Indicator Species and Diversity in Mangroves at Darunu Mangrove Park

Mangrove ecosystems play a crucial role in maintaining the ecological balance of coastal areas, including protection against abrasion, providing habitat for marine species, and acting as a carbon sink. This study aims to identify indicator species and analyze biodiversity in Darunu Mangrove Park, Darunu Village, Wori Subdistrict, North Minahasa Regency. The research was conducted over three months (May–July 2024) using a line transect method for vegetation data collection. The results show that three dominant mangrove species were identified: Rhizophora apiculata, Rhizophora mucronata, and Sonneratia alba. R. mucronata exhibited significant dominance, both in terms of mature trees and saplings, and had the highest Important Value Index (IVI). The mangrove species diversity in this area is classified as low, with the. Diversity Index (H’) indicates an imbalance in the ecosystem's species composition. The Dominance Index (C) and Evenness Index (E) analyses indicate strong dominance by certain species, particularly R. mucronata. This study recommends the importance of enhanced monitoring and more intensive conservation efforts, including the replanting of threatened mangrove species and raising community awareness of mangrove ecosystem conservation. Keywords: Darunu Mangrove Park, Diversity, Indicator Species, Important Value Index.   Abstrak   Ekosistem mangrove memiliki peran penting dalam menjaga keseimbangan ekologi pesisir, meliputi perlindungan terhadap abrasi, penyedia habitat bagi spesies laut, dan sebagai penyerap karbon. Penelitian ini bertujuan untuk mengidentifikasi spesies indikator dan menganalisis keanekaragaman hayati di Darunu Mangrove Park, Desa Darunu, Kecamatan Wori, Kabupaten Minahasa Utara. Penelitian dilaksanakan selama tiga bulan (Mei-Juli 2024) dengan menggunakan metode transek garis untuk pengambilan data vegetasi. Hasil penelitian menunjukkan bahwa terdapat tiga jenis mangrove dominan, yaitu R. apiculata, R. mucronata, dan S. alba. Jenis R. mucronata menunjukkan dominasi yang signifikan, baik pada tingkat pohon maupun pancang, serta memiliki nilai Indeks Nilai Penting (INP) tertinggi. Keanekaragaman jenis mangrove di kawasan ini tergolong rendah dengan Indeks Keanekaragaman (H’) menunjukkan ketidakseimbangan spesies dalam ekosistem. Analisis Indeks Dominansi (C) dan Indeks Kemerataan (E) mengindikasikan adanya dominasi yang kuat dari beberapa spesies tertentu, terutama R. mucronata. Penelitian ini merekomendasikan pentingnya pemantauan dan upaya konservasi yang lebih intensif, termasuk penanaman kembali spesies mangrove yang terancam dan peningkatan kesadaran masyarakat terhadap pelestarian ekosistem mangrove. Kata kunci: Darunu Mangrove Park, Indeks Nilai Penting, Keanekaragaman, Spesies indicato

Description of Yellowfin Tuna Processing

Morotai Island Regency has very abundant potential, namely tuna. The abundance of tuna fishermen's catches has become an opportunity to develop tuna loin processing, one of which is at PT. Harta Samudra Morotai. This research aims to describe the processing process carried out at PT. Harta Samudra. PT. Harta Samudra has 90 employees, 84 of whom are residents. Of the total employees, 11 are permanent employees and the other 79 are daily employees. The tuna loin processing process refers to SNI 01-4104.3-2006: receiving, beheading, butchering, trimming, gas room, chiller, retouching, packing, stuffing, and laboratory analysis. Keywords: Yellowfin Tuna; Frozen Loin Tuna; PT. Harta Samudra Abstrak Kabupaten Pulau Morotai, memiliki potensi yang sangat melimpah, yakni tuna. Melimpahnya hasil tangkapan nelayan tuna, menjadi peluang dikembangkannya pengolahan Tuna loin salah satunya di PT. Harta Samudra Morotai. Penelitian ini bertujuan untuk mendeskripsikan proses pengolahan yang dilakukan di PT. Harta Samudra. PT. Harta samudra memiliki 90 karyawan, 84 diantaranya merupakan penduduk lokal. Dari total keseluruhan karyawan 11 diantaranya merupakan karyawan tetap dan 79 lainnya merupakan karyawan harian. Proses pengolahan tuna loin mengacu pada SNI 01-4104.3-2006 yakni receiving, deheading, butchering, trimming, gas room, chiller, retouching, packing, stuffing dan analisis laboratorium. Kata Kunci : Tuna Ekor Kuning; Tuna Loin Beku; PT. Harta Samudr

Management Strategies for Sea Cucumber (Holothuroidea) Fisheries Resources in West Likupang Sub-district

Indonesia is a tropical country with high marine biodiversity, including sea cucumber. The high demand for sea cucumber has led fishermen to catch sea cucumber regardless of the type or size suitable for harvesting. The lack of cultivation and regulations governing the protection of sea cucumbers has caused some species to be endangered. Sea cucumber species with high selling prices are increasingly difficult to find in West Likupang District. This study aims to identify strategies for managing sea cucumber fisheries sustainably and provide policy recommendations for their sustainable management in West Likupang District. This study used a survey method and then analyzed it with a SWOT analysis (strengths, weaknesses, opportunities, threats). The SWOT analysis reveals several strategies for achieving sustainable sea cucumber fisheries: legislation, conservation efforts, aquaculture development, regulated fishing, proper post-harvest handling, and educating fishermen on regulations. Keywords: Management, regulation, conservation, sea cucumber, SWOT Abstrak Indonesia merupakan negara tropis yang mempunyai keanekaragaman hayati laut yang tinggi, salah satunya ialah sumber daya trepang (Holothuridea). Permintaan pasar yang tinggi terhadap trepang, menyebabkan nelayan menangkap trepang tanpa mengindahkan jenis dan ukuran yang layak panen. Belum adanya budi daya dan regulasi yang mengatur perlindungan terhadap trepang menyebabkan beberapa spesies sudah terancam punah. Spesies trepang dengan harga jual yang tinggi makin sulit ditemukan terutama di Kecamatan Likupang Barat. Penelitian ini bertujuan untuk menentukan strategi pengelolaan sumber daya perikanan trepang, untuk mencapai perikanan trepang yang berkelanjutan, dan membuat rujukan atau rekomendasi kebijakan untuk pengelolaan sumber daya perikanan trepang (Holothuroidea) yang berkelanjutan secara umum Di Provinsi Sulawesi Utara, khususnya di Likupang Kabupaten Minahasa Utara. Penelitian ini menggunakan metode survei kemudian dianalisis dengan analisis SWOT (kekuatan, kelemahan, peluang, dan ancaman). Berdasarkan hasil analisis, terdapat beberapa strategi yang dapat dikembangkan untuk mencapai perikanan trepang yang berkelanjutan, yakni: regulasi berupa peraturan perundangan, upaya konservasi, pengembangan usaha budidaya, penangkapan yang terukur, penanganan pasca panen/penangkapan dari alam, dan sosialisasi kepada nelayan terkait peraturan Kata kunci: Pengelolaan, regulasi, konservasi, trepang, SWO

Induction Time And Sedative (Recovery) Time In Closed System Transportation Of Tawes Fish (Barbonymus gonionotus) Anesthetized With Clove Oil At Different Temperatures

The conservation of tawes fish (Barbonymus gonionotus) is carried out through aquaculture and restocking, where seed transportation is a crucial factor affecting survival rates. Mishandling during transport can increase stress, metabolism, and mortality risk. Reducing stress during transport can be achieved by using natural anesthetic agents such as clove oil (Eugenia aromatica) and low-temperature regulation. This study aims to analyze the effects of clove oil dosage and temperature on the induction time and recovery of tawes fish seeds. The experiment was designed using a completely randomized design (CRD) with two factors: clove oil dosage (0 ppm, 5 ppm, 10 ppm) and temperature (16–19°C and 24–27°C), with 18 experimental units (3 replications). Data were analyzed using ANOVA (JMP-SAS). The results showed that combining clove oil and temperature significantly affected induction and recovery times. The 10 ppm clove oil treatment at 16–19°C resulted in the fastest induction time, while the 0 ppm treatment at 24–27°C led to the fastest recovery. The interaction between these factors demonstrated that clove oil significantly influenced the fish's response to temperature changes. Keywords: tawes fish seed, transportation, temperature, clove oil, induction, sedative.   Abstrak   Pelestarian ikan tawes (Barbonymus gonionotus) dilakukan melalui budidaya dan restocking, di mana transportasi benih menjadi faktor krusial yang memengaruhi tingkat kelangsungan hidupnya. Kesalahan dalam penanganan dapat meningkatkan stres, metabolisme, dan risiko kematian benih. Upaya menekan stres selama transportasi dilakukan dengan penggunaan agen pembius alami, seperti minyak cengkih (Eugenia aromatica) dan pengaturan suhu rendah.Penelitian ini bertujuan menganalisis pengaruh dan dosis minyak cengkih serta suhu terhadap waktu induksi dan pemulihan (recovery) benih ikan tawes. Percobaan menggunakan rancangan acak lengkap (RAL) dengan dua faktor: dosis minyak cengkih (0 ppm, 5 ppm, 10 ppm) dan suhu (16–19°C dan 24–27°C), dengan 18 unit percobaan (3 ulangan). Data dianalisis menggunakan ANOVA (JMP-SAS).Hasil penelitian menunjukkan bahwa kombinasi minyak cengkih dan suhu berpengaruh signifikan terhadap waktu induksi dan pemulihan benih. Perlakuan 10 ppm minyak cengkih pada suhu 16–19°C menghasilkan waktu induksi tercepat, sedangkan tanpa minyak cengkih pada suhu 24–27°C mempercepat pemulihan. Interaksi kedua faktor ini menunjukkan bahwa minyak cengkih secara nyata mempengaruhi respons ikan terhadap perubahan suhu. Kata kunci: benih tawes, transportasi, suhu, minyak cengkih, induksi, sedatif

Analysis of Mangrove Vegetation Index Using Landsat 8 Images in Dodinga Bay, West Halmahera

Mangrove vegetation can be easily recognized from remote-sensing satellite images compared to other terrestrial vegetation. The vegetation index is applied to the satellite images to highlight the aspect of vegetation density. This study aims to determine the correlation between the value of the vegetation index and mangrove canopy cover data to achieve a proper vegetation index to estimate the density of the mangrove canopy. The data needed are satellite imagery from Landsat 8 and mangrove canopy cover in sampling locations along the coast of Dodinga Bay, West Halmahera. Image data analysis includes radiometric correction, image sharpening, masking, classification, and accuracy tests. The vegetation index algorithms used were NDVI, GNDVI, and IM, and regression analysis was carried out for correlation tests. The analysis results obtained four different land cover classes with an overall accuracy of 97.70% and a kappa coefficient of 0.9688. The IM vegetation index showed an excellent correlation with mangrove canopy cover compared to GNDVI and NDVI. The determination coefficient (R²) of the IM is 0.6765; GNDVI (0.4897) and NDVI (0.4825). The IM classification produces four levels of mangrove canopy density, i.e., sparse (7.40 ha), moderate (628.33 ha), dense (921.22 ha), and very dense (16.45 ha). Keywords: mangrove, Landsat 8 images, vegetation index, Dodinga Bay Abstrak Objek vegetasi mangrove paling mudah diidentifikasi dengan menggunakan citra satelit penginderaan jauh dibandingkan objek vegetasi darat lainnya. Indeks vegetasi diterapkan terhadap citra untuk menonjolkan aspek kerapatan vegetasi. Penelitian ini bertujuan mengetahui korelasi antara nilai indeks vegetasi dengan data tutupan kanopi mangrove, sehingga didapatkan indeks vegetasi yang sesuai untuk menduga kerapatan kanopi mangrove. Data yang diperlukan yaitu citra Landsat 8 dan tutupan kanopi mangrove di lapangan. Analisis data citra terdiri dari koreksi radiometrik, penajaman citra, masking, klasifikasi dan uji akurasi. Algoritma indeks vegetasi yang digunakan yaitu NDVI, GNDVI dan IM, serta dilakukan analisis regresi untuk uji korelasi. Hasil analisis mendapatkan empat kelas tutupan lahan yang berbeda dengan overall akurasi sebesar 97,70 % dan kappa coefisien sebesar 0,9688. Indeks vegetasi IM menunjukkan korelasi sangat baik dengan tutupan kanopi mangrove dibandingkan GNDVI dan NDVI. Koefisien determinasi (R²) IM adalah 0,6765; GNDVI (0,4897) dan NDVI (0,4825). Klasifikasi IM menghasilkan empat tingkat kerapatan kanopi mangrove yaitu mangrove jarang (7,40 ha), mangrove sedang (628,33 ha), mangrove lebat (921,22 ha), dan mangrove sangat lebat (16,45 ha). Kata kunci: mangrove, citra Landsat 8, indeks vegetasi, Teluk Doding

Analysis Of Tsunami Hazard Potential On The Coast Of Bitung City, North Sulawesi

This thesis aims to study the tsunami hazards in the Maluku Sea region, particularly in the coastal area of Bitung, Indonesia. The research focuses on modeling and analyzing the potential tsunamis triggered by earthquake events in that region. The data used includes bathymetry, topography, coastline, and river data obtained from the Geospatial Information Agency (Badan Informasi Geospatial-BIG). The tsunami modeling process utilizes the software COMCOT (Cornell Multi-grid Coupled Tsunami).  The earthquake source parameters (PusGen) used in the modeling, such as magnitude, focal depth, length of the fault plane, the width of the fault plane, dislocation of the fault plane, strike, dip, slip/rake, and modeling area, were obtained from worst-case scenarios based on PusGen's research results. The research consists of two main stages: the pre-verification stage, where data processing and tsunami modeling are conducted, and the verification stage, where field surveys are carried out to determine the coordinates for Temporary Evacuation Sites (TEP) and Final Evacuation Sites (FEP).  Various equipment, such as GPS, altimeters, stopwatches, cameras, and drones, are used during the field verification. The research procedures include a literature review, data collection of topography, bathymetry, earthquake parameters, and fault mechanism. Subsequently, tsunami modeling is conducted, and hazard analysis is performed based on the model results. Tsunami hazard maps are generated to highlight high-risk areas in the coastal region of Bitung, and evacuation routes are identified to prepare the coastal community of Bitung to face potential tsunami threats.  The research offers important information to assist in the development of warning systems and efficient evacuation strategies to protect the coastal community of Bitung from tsunamis' devastating impacts. Keywords: Tsunami; Bitung; coastal area; earthquake; PusGe

Study of Scleractinian Coral Recruitment in the Waters of Tanjung Pisok and Siladen Island, Bunaken National Park

The research aimed to determine the recruitment density value of scleractinian coral juveniles in Tanjung Pisok (Meras and Bahowo) and Siladen Island. The method for selecting observation locations uses purposive sampling and collecting coral juvenile recruitment data using underwater photo transects. The results of this research obtained data on genus, size, and density values ​​for coral juvenile recruitment. The coral genera found at Station I were 19 genera with the largest number being the Porites genus, 32 colonies, Station II 13 genera with the largest number being the Favites genus, 32 colonies, and at Station III 17 genera with the largest number being the Porites genus, 32 colonies. Coral juveniles in this study were more dominant in the 2 cm - 2.9 cm size group, for Station I 63 colonies, Station II 54 colonies and Station III 32 colonies. Based on the results of this research, it shows that the coral recruitment density at Station I with a value of 12.38 colonies/m² is higher than Station II, the coral recruitment density at Station II with a value of 12.23 colonies/m² is higher than Station III with a value of 7.21 colonies/m². Keywords: Recruitment; Scleractinia; Underwater Photo Transect; Bunaken National Park Abstrak Tujuan penelitian menentukan nilai densitas rekrutmen juvenil karang scleractinia di perairan Tanjung Pisok (Meras dan Bahowo) dan pulau Siladen. Metode pemilihan lokasi pengamatan menggunakan purposive sampling dan metode pengumpulan data rekrutmen juvenil karang menggunakan underwater photo transect. Hasil penelitian ini memperoleh data genus, ukuran dan nilai densitas rekrutmen juvenil karang. Genus karang yang didapat di Stasiun I yaitu 19 genus dengan yang terbanyak genus Porites 32 koloni, Stasiun II 13 genus dengan yang terbanyak genus Favites 32 koloni, dan Stasiun III 17 genus dengan yang terbanyak genus Porites 32 koloni. Juvenil karang dalam penelitian ini lebih dominan pada kelompok ukuran 2 cm - 2.9 cm, untuk Stasiun I 63 koloni, Stasiun II 54 koloni dan Stasiun III 32 koloni. Berdasarkan hasil penelitian ini menunjukkan densitas rekrutmen karang di Stasiun I dengan nilai 12,38 koloni/m² lebih tinggi dari Stasiun II, densitas rekrutmen karang di Stasiun II dengan nilai 12,23 koloni/m² lebih tinggi dari Stasiun III dengan nilai 7,21 koloni/m². Kata kunci: Rekrutmen; Scleractinia; Taman Nasional Bunaken; Underwater Photo Transec

The Function Of Spatial Planning In Maintaining The Environmental Preservation Of West Pasaman District

Abstract: This research examines the role of spatial planning in preserving the environment in West Pasaman Regency. The main aim of this research is to evaluate how the implementation of spatial planning can support environmental conservation efforts. The method used is qualitative descriptive analysis with a case study approach. Data was collected through in-depth interviews, field observations, and analysis of spatial planning documents. The research results show that good and well-planned spatial planning can reduce pressure on natural resources and improve the quality of the living environment. However, challenges such as weak law enforcement and low public awareness are still the main obstacles. In conclusion, the integration of spatial planning policies that pay attention to environmental aspects is very crucial to achieving sustainable development in West Pasaman Regency. Keywords: Environment; Spatial; Continuity;   Abstrak Penelitian ini menelaah peran tata ruang dalam menjaga kelestarian lingkungan hidup di Kabupaten Pasaman Barat. Tujuan utama dari penelitian ini adalah untuk mengevaluasi bagaimana implementasi tata ruang dapat mendukung upaya pelestarian lingkungan. Metode yang digunakan adalah analisis deskriptif kualitatif dengan pendekatan studi kasus. Data dikumpulkan melalui wawancara mendalam, observasi lapangan, dan analisis dokumen perencanaan tata ruang. Hasil penelitian menunjukkan bahwa tata ruang yang baik dan terencana dapat mengurangi tekanan terhadap sumber daya alam dan meningkatkan kualitas lingkungan hidup. Namun, tantangan seperti lemahnya penegakan hukum dan rendahnya kesadaran masyarakat masih menjadi hambatan utama. Kesimpulannya, integrasi kebijakan tata ruang yang memperhatikan aspek lingkungan sangat krusial untuk mencapai pembangunan berkelanjutan di Kabupaten Pasaman Barat. Kata Kunci : Lingkungan; Tata Ruang; Keberlanjutan