Jurnal Ilmu dan Teknologi Kelautan Tropis
Journal Title : Jurnal Ilmu dan Teknologi Kelautan Tropis Abbreviation : J. Ilmu dan Teknologi Kelautan Tropis Scope : Marine biology, marine ecology, biological oceanography, chemical oceanography, physical oceanography, dynamic oceanography, coral reef ecology, marine acoustics, marine remote sensing, marine geographic information systems, marine microbiology, marine pollution, marine aquaculture, post-harvest fisheries technology, integrated coastal management (ICM), marine biotechnology, air-sea interactions, marine engineering. Type of manuscript : Original Research, Systematic Reviews, and Meta-Analyses Frequency : April, August, December DOI : 10.29244/jitkt Print ISSN : 2620-309X Online ISSN : 2087-9423 Publisher : Department of Marine Science and Technology, Faculty of Fisheries and Marine Sciences-IPB University, in collaboration with the Association of Indonesian Maritime Specialists, and the Association of Indonesian Coastal Management Experts. Language : English, Bahasa Indonesia Citation Analysis : Google Scholar Open Access Policy : Creative Commons Attribution (CC BY) Preservation Archiving : PKP PN
Department of Marine Science and Technology, Faculty of Fisheries and Marine Science, IPB University
This work is licensed under a Creative Commons Attribution 4.0 International License. Jurnal Ilmu dan Teknologi Kelautan Tropis i is an open-access journal, meaning that all content is freely available without charge to the user or their institution. Users are allowed to read, download, copy, distribute, print, search, or link to the full texts of the articles in this journal without needing to request prior permission from the publisher or the author. All articles published by Jurnal Ilmu dan Teknologi Kelautan Tropis are licensed under the Creative Commons Attribution 4.0 International License. This allows for unrestricted use, distribution, and reproduction in any medium, provided proper credit is given to the original authors. Authors submitting manuscripts should understand and agree that the copyright of published manuscripts is retained by the authors. Copyright encompasses the exclusive rights of authors to reproduce, distribute, and sell any part of the journal articles in all forms and media. Reproduction of any part of this journal, its storage in databases, and its transmission by any form or media is allowed without written permission from Jurnal Ilmu dan Teknologi Kelautan Tropis.
Machine Learning-Based Mapping of Mangrove Forest Changes from Sentinel-2 in Balikpapan Bay, East Kalimantan
Balikpapan Bay contains extensive mangrove forests which play an important role as habitat for a range of species and in providing a range of ecosystem services. In recent years, the mangrove forests around Balikpapan Bay are increasingly being lost and degraded due to development pressures. Thus, change detection in mangrove ecosystem has become highly relevant, as it can provide essential information to support the conservation practices and coastal management. This study aims to map mangrove forest change in Balikpapan Bay, East Kalimantan over a five-year period from Sentinel-2 using machine learning. Five machine learning algorithms (Random Forest (RF), Support Vector Machine (SVM), Classification and Regression Tree (CART), K-Nearest Neighbors (KNN), and Minimum Distance), implemented on the Google Earth Engine platform, were evaluated to determine the most suitable method. The evaluation results indicate that RF, SVM, and CART yielded mangrove mapping accuracies of 80% or higher. Notably, the CART algorithm surpassed the other tested models, demonstrating the highest overall accuracy of 84% and a Kappa coefficient of 0.78. Mapping using the selected CART model shows that, between 2020 and 2025, mangrove areas in Balikpapan Bay decreased by 21% (2,906.17 ha). Approximately 97% (2,834.49 ha) of this loss is concentrated in the North Penajam Paser, which has a high rate of land conversion to built-up areas.
Copyright (c) 2025 Muhammad Abdul Ghofur Al Hakim, S.Kel., M.Si, Dr. Maya Eria Br Sinurat, S.Kel, M.Si, Nurul Ain Najwa Zulkifle, Nurmawati, Ahmad Azwar Mas’ud M https://creativecommons.org/licenses/by/4.0
Echogram Image Analysis for Pelagic Fish School Classification in Bungus Waters, West Sumatra
Tropical marine fisheries are characterized by high species diversity but low individual abundance per species within the same water column, making the detection of distinct fish schools challenging using hydroacoustic technology. However, a hydroacoustic survey conducted in Bungus, West Sumatra, in October 2023 revealed the presence of approximately 14 identifiable fish schools of varying sizes, indicating the potential for further analytical investigation. This study aims to characterize and classify fish schools by analyzing echogram imagery and extracting key acoustic parameters through a statistical multivariate approach. Acoustic data were collected using a Simrad EK-15 echosounder operating at 200 kHz. Subsequent data processing was performed in Echoview, followed by multivariate analysis. From an initial dataset of 24 detected schools, 12 parameters were retained for analysis. These parameters were categorized into three groups: (1) energetic parameters, including target strength (TS), volume backscattering strength (Sv), area backscattering strength (Sa), skewness, and kurtosis; (2) morphometric parameters, consisting of school height, length, perimeter, and volume; and (3) bathymetric parameters, represented by average school depth. Latitude and longitude were included as supplementary spatial descriptors. Among the 12 parameters, latitude did not contribute to school characterization and was therefore excluded from further analysis. Multivariate results indicated that morphometric parameters (particularly school height and area) and energetic parameters (Sa and TS) were the most influential in differentiating school structure. Cluster analysis based on the remaining 11 parameters identified two distinct groups of fish schools: Group 1, comprising 14 schools (58.3%), and Group 2, comprising 10 schools (41.7%). These findings demonstrate that integrating hydroacoustic metrics with multivariate statistical methods provides an effective framework for identifying and characterizing fish schools in tropical waters with inherently complex species assemblages.
Copyright (c) 2025 Jovian Lansky, Steven Solikin, Sri Pujiyati, Totok Hestirianoto https://creativecommons.org/licenses/by/4.0
Hard Coral (Porites Lutea) Growth Simulation using Fuzzy Logic Method in Tunda Waters, Banten Province
Corals grow annually at varying rates, influenced by environmental conditions. As key indicators of marine ecosystem health, studying coral growth is essential for predicting the impacts of environmental change. While previous research has explored coral growth extensively, most studies focus on existing conditions and the descriptive influence of environmental parameters. In fact, coral growth time-series data offer potential for deeper analysis, particularly in identifying dominant periodicities and enabling long-term projections. This study aims to develop an annual coral growth model using fuzzy logic approach. The Indian Ocean Dipole (IOD) is identified as a significant factor influencing the growth of Porites lutea in Tunda Island. Variations in sea surface temperature during IOD events notably affect coral growth, with positive IOD phases (IOD+) generally enhancing it. Analysis shows that the annual growth rings of Porites lutea in the northern station of Tunda Island, which borders open waters respond more slowly to SST fluctuations compared to the southern station, which is more sheltered. Fuzzy simulation results suggest that corals may be able to adapt to climate change. By the year 2085, coral growth is projected to recover from -0.75 cm to 0.1 cm by 2100. Based on SST projections from 1900 to 2100, SST anomalies are expected to continue increasing, reaching +0.45 °C.
Copyright (c) 2025 Muhamad Kemal Idris, Alan Frendy Koropitan, Neviaty P Zamani https://creativecommons.org/licenses/by/4.0
Seagrass Restoration Review: Spatial Analysis of Potential Habitats, Innovative Restoration Methods, and Predictive Modeling for Monitoring
Seagrass ecosystems are vital for maintaining marine ecological balance, supporting the blue carbon cycle, offering habitat for marine organisms, and safeguarding coastal areas against erosion. Nevertheless, seagrass ecosystems worldwide are declining substantially due to human activities and climate change. This trend is also evident in Indonesia, where approximately 7% of seagrass coverage is lost annually. This research examines existing literature on seagrass restoration by focusing on three key approaches: spatial assessment of suitable habitats, advancements in physical restoration techniques, and the creation of predictive models for evaluating restoration outcomes. The goal is to offer comprehensive insights into the challenges and prospects for improving management and establishing more effective and sustainable restoration strategies in coastal environments. A Systematic Literature Review (SLR) combined with bibliometric analysis was conducted on 177 publications from the Scopus database spanning 2019 to 2024 to identify research trends, technological advancements, and existing challenges in seagrass restoration. The research emphasizes the necessity of a holistic approach to seagrass restoration, incorporating spatial analysis, developing flexible restoration techniques, and implementing predictive modeling and statistical assessments to enhance long-term planning and monitoring efforts. The case study in Jepara demonstrates the effectiveness of participatory approaches at the local scale, despite limitations in technology and long-term monitoring. Integrating spatial and digital technologies, strengthening local capacity, international collaboration, and multidisciplinary integration are key to improving the effectiveness and sustainability of seagrass restoration, while strengthening its contribution to coastal resilience and climate change mitigation.
Copyright (c) 2025 Nurhasanah Tika, Yasmin Fauziah, Azzahra Shinta Bilqis Nurfata, Eko Koesratmoko, Mufti Petala Patria, Denny Riama Silaban https://creativecommons.org/licenses/by/4.0
Long-Term Monitoring of Mangrove Resilience in the Sundarbans after Cyclone Sidr and Aila using Landsat-Derived Vegetation Indices
The present work aims at assessing vegetation patterns and of the recovery process over the long term (2006 to 2025) in the Sundarbans mangroves based on the NDVI and SAVI. Landsat 5 TM and Landsat 8 OLI surface reflectance images were processed in Google Earth Engine to derive seasonal composites for the dry season (December–February). A supervised classification method was used to delineate five land-cover classes, namely water bodies, bare soil, sparse, intermediate, and dense vegetation. Accuracy assessment was carried out by visual interpretation of the sample points by using Google Earth Pro where overall accuracy was in the 88–93% over the entire study period. In 2006, dense vegetation was the most dominant (~68%) and sparse and intermediate other categories had low frequency and water bodies covered 21% of plots. For post-Sidr in 2008, nearly all plants showed more severe damage (76-79%). Post-Aila (2010) data suggested continuous intermediate (46%) and sparse (25%) vegetation cover but with negligible closed canopy. During 2015, the dense vegetation recovered to 60%, and dynamic changes among dense, intermediate, and sparse vegetation areas emerged, and the area of dense vegetation was up to 67% in 2025 indicating that the long-term restoration exhibits space heterogeneity. NDVI was effective for monitoring the overall trend of large scale canopy, while SAVI was able to capture very small scale regeneration and understory growth. The findings show the impressive resilience of the Sundarbans and the significance of such key ecological processes as canopy recovery and succession, and the need for more adaptive management to improve mangrove resilience in cyclone-prone coastal areas.
Copyright (c) 2025 Md. Saifur Rahman, Md. Mostafizur Rahman, Syed Hafizur Rahman https://creativecommons.org/licenses/by/4.0
Heavy Metal Absorption in Lasolo Bay using a Composite of Cashew-Based Activated Charcoal and Iron Sand, Southeast Sulawesi, Indonesia
This study used a composite of activated charcoal and iron sand extract to reduce the concentrations of heavy metals (Cu, Ni, Zn, Pb, and Cd) in polluted seawater. The grain size of the composite was varied to 60 mesh, 100 mesh, and 200 mesh, with a ratio of activated charcoal to iron sand of 2:3 to optimize absorption. The composite was then compacted into pellets with compaction pressures of 42.2 Pa, 84.8 Pa, and 141.5 Pa, respectively, to achieve optimum compressive strength. The concentrations of heavy metals were measured using an Atomic Absorption Spectrophotometer (AAS). The optimal compaction pressure for the composite was found to be 141.5 Pa, with absorption efficiencies of 61% for Zn, 96% for Pb, 48% for Cd, 90% for Cu, and 94% for Ni. According to the research results, the highest absorption was obtained in composites with a grain size of 200 mesh, with absorption efficiencies of 62.21% for Zn, 96.87% for Pb, 48.14% for Cd, 90.98% for Cu, and 94.15% for Ni. The greater the compaction pressure exerted on the composite, the higher the absorption percentage of the composite pellets. Conversely, a finer grain size also contributes to higher absorption.
Copyright (c) 2025 Rosliana Eso, Irawati, Bahdat, Asmadin, Arman, Syahdin Alfat, Erzam S Hasan https://creativecommons.org/licenses/by/4.0
Analysis of Water Suitability for Ecotourism Development on Several Beaches in Morella Village, Central Maluku Regency, Maluku Province
Maluku is an archipelago whose territory is coastal and marine which is suitable for tourism. The tourism value and attractiveness of coastal areas should be developed through marine tourism. This study aims to analyze current speed, water depth, pH, DO, temperature, salinity, sigma-t, chlorophyll-a, and turbidity-m as physical, chemical, and biological indicators in the Lubang Buaya and Moki Beach ecotourism areas. Water sampling was carried out using Kemmerer bottles at different depths, namely at the surface and at a depth of 20 meters.Water samples are used to analyze chemical elements both horizontally and vertically. Sample analysis was carried out at the Oceanology Laboratory and Basic Biology Laboratory of Pattimura University.The test parameters in this study were water depth, temperature, salinity, sigma-t, chlorophyll-a, turbidity-m using conductivity, temperature, and depth (CTD), current speed using a current meter, pH using a pH meter, and dissolved oxygen (DO) using a DO meter. The waters of Lubang Buaya Beach and Moki Beach, Morella Village, Central Maluku Regency, Maluku Province have water conditions, namely pH, temperature, salinity, sigma-t, chlorophyll-a, turbidity-m, and brightness with appropriate categories, while DO with an inappropriate category based on water assessment standards. The assessment results show the waters' suitability for ecotourism development at a surface depth of 0 meters and a bottom depth of 3 to 25 meters. The minimum current speed of 0.003 m/s and the maximum current speed of 0.36 m/s are suitable for boating, banana boating and jet skiing activities.
Copyright (c) 2025 Fredy Leiwakabessy, Muhammad Tarmizi Kubangun, Eifan Boyke Pattiasina https://creativecommons.org/licenses/by/4.0
Kajian Karakteristik Gelombang di Perairan Teluk Batang, Kalimantan Barat
Teluk Batang Port is the economic gateway for the North Kayong Regency region and its surroundings. The port is a national asset of strategic value, so security factors from a shipping perspective need to be considered. This research was conducted to determine the characteristics of waves in the waters of Batang Bay as information in the field of sailing safety. The wind data used ECMWF (European Center For Medium-Range Weather Forecasting) data for wave hindcasting. Wave model simulation using 2D numerical model. The results of the wave model simulation based on the wind season with three observation location points were obtained, the highest Hs in the four seasons occurred at observation point 1. The highest Hs in the west season occurred in 2015 at 0.77 meters and Ts 3 .17 seconds. The highest Hs transition season 1 occurred in 2021 at 0.74 meters and Ts 3.30 seconds. The highest east monsoon Hs occurred in 2018 at 0.57 meters and Ts 2.76 seconds. The highest Hs transition season 2 occurred in 2018 at 0.50 meters and Ts 2.97 seconds. The pattern of wave propagation in Batang Bay, the wave spreads from outside the bay into the bay. In the wave propagation process, the wave height will become smaller due to changes in water depth. The waves in the waters of Batang Bay are safe for sailing throughout the year.
Sedimentation Rate Analysis in Public Port, Lhokseumawe City
Sedimentation is the process of deposition of material from rocks that is transported by the movement of water and wind. Sedimentation that takes place continuously causes siltation in water areas. If shallowing occurs in the port area, it will have an impact on the decline in port functions and even threaten the security of sea transportation routes. The purpose of this study was to analyze the rate of sedimentation in the General Port of Lhokseumawe City which includes sediment characteristics and oceanographic parameters that affect the sedimentation process. This study used a survey method with purposive sampling at 4 observation stations for 7 days. The highest sedimentation rate was found at Station 4 which was 6,22 mg/cm2/day and the lowest at Station 2 which was 3,65 mg/cm2/day. The dominant sediment grain size in the General Port of Lhokseumawe City is very fine sand type with a value of 38,04%. PCA analysis of very fine sand type sediments deposited the most. The highest current velocity at station 2 with a value of 0.10 m/s while the highest tide on the first day was 320 cm in height. The current speed has an inversely correlation to the sedimentation rate with a value of 81,52%.
Variasi Musiman Ketebalan Lapisan Termoklin di Perairan Barat Sumatra
The oceanographic dynamics of the western waters of Sumatra can be observed through the characteristics of the thermocline layer. Information on thermocline thickness is essential for understanding seasonal variations over the past decade. This study aims to identify the seasonal variability in thermocline thickness along the coastal and offshore regions of western Sumatra by analyzing six observation points representing both zones. A quantitative and descriptive approach was employed, utilizing monthly average vertical temperature data from 2010 to 2019, obtained from the Marine Copernicus database. Data processing was conducted using Panoply software and Microsoft Excel 2010, producing seasonal average thermocline thickness values and time series graphs. The results show that the highest thermocline thickness was recorded at 130.3 meters in the coastal area of Bengkulu during the first transitional season, and 138.7 meters in the offshore area of Lampung during the southeast monsoon. In contrast, the lowest thermocline thickness was observed during the northwest monsoon, reaching 74.9 meters from the coast to offshore regions of Bengkulu and Lampung, as well as in the coastal to offshore areas of Aceh in August. The increased thermocline thickness during the first transitional season in Bengkulu to Lampung waters is attributed to the distribution of surface winds transporting warm water masses along the western coast of Sumatra. Meanwhile, the thinner thermocline layer observed during the southeast monsoon suggests the occurrence of upwelling in the region.
Copyright (c) 2025 Zulfatur Rohmah Zulfa
Estimasi Serapan dan Nilai Ekonomi Karbon Rhizophora apiculata di Kawasan Konservasi Perairan Nias Utara
Mangrove ecosystems are categorized as blue carbon due to their ability to store atmospheric carbon. Rhizophora apiculata, the dominant mangrove species in the Sawo-Lahewa conservation area, North Nias Regency, plays a key role in carbon sequestration and is widely used in ecosystem rehabilitation. This study aims to estimate the carbon stock and its economic value under different compensation scenarios. A non-destructive method was applied to estimate biomass using allometric equations, followed by calculations of carbon stock and CO₂ absorption. The economic value was assessed using three approaches: Forest Carbon Partnership Facility (FCPF), the U.S. government's Social Cost of Carbon (SCC), and Indonesia’s domestic market under the HPP Law. The estimated carbon stock of R. apiculata is 3,687.78 tons/ha, equivalent to 13,534.15 tons of CO₂ absorbed. In 2023, its economic value is approximately IDR 989.35 million (FCPF), IDR 8.31 billion (SCC), and IDR 406.02 million (domestic market). Projected values in 2043 increase to IDR 2.17 billion, IDR 18.21 billion, and IDR 889.65 million, respectively. These results highlight the ecological and economic importance of R. apiculata in supporting climate regulation services. Strategic conservation and sustainable management of mangroves can enhance their carbon offset potential, contributing to both environmental and economic benefits.
Karakteristik Pola Arus di Perairan Teluk Jakarta Pada Musim Barat dan Timur
Jakarta Bay is a coastal area influenced by both natural factors (wind, currents, waves) and human activities (residential areas, coastal development, industry, and resource exploitation). The monsoon phenomenon in the Java Sea affects hydrodynamic patterns, especially current dynamics in Jakarta Bay. This study analyzes changes in current patterns during two distinct monsoon seasons (west and east) in 2021 using a hydrodynamic modeling approach. The model was developed using OpenFlows software with input data including bathymetry, tidal, wind, and wave conditions. Model validation was conducted using tidal and current measurements from field observations in March and August 2021. The results show seasonal variations in current direction and velocity, both in tidal phases and non-tidal (residual) currents. The current patterns aligned with seasonal wind directions, indicating a strong monsoonal influence. Model validation using Root Mean Square Error (RMSE) and Taylor diagram analysis demonstrated good agreement between modeled and observed data, confirming the model's reliability. These hydrodynamic modeling results can serve as a foundation for further studies, such as simulations of pollutant, sediment, and debris dispersion in Jakarta Bay.
Copyright (c) 2025 Teguh Nugraha, I Wayan Nurjaya, Rastina
Analisis Hubungan Kondisi Ekosistem Mangrove terhadap Produksi Ikan di Kawasan Konservasi Perairan Kayong Utara
The North Kayong Regency Marine Conservation Area serves to protect and sustainably utilize fishery resources, including penaeid shrimp, porpoises, and mangrove ecosystems. Effective management requires spatial data on conservation targets to support comprehensive planning and evaluation. This study analyzes the relationship between the mangrove vegetation index (NDVI), derived from satellite imagery, and fish production in the conservation area using a mangrove productivity approach. The research comprises four stages: (i) analysis of fish stock and production using the mangrove productivity model, (ii) correlation analysis between fish production and mangrove conditions, (iii) measurement of physicochemical water parameters, and (iv) correlation analysis between physicochemical water factors and fish production. The results indicate that the average daily mangrove litterfall production across all stations is 2.09±0.86 g dry weight/m²/day or 8.42±3.47 tons/ha/year, while fish production ranges from 190.17 to 690.28 kg/ha/year, with an average of 448.82±185.61 kg/ha/year. A moderate positive correlation is observed between NDVI and fish production (r = 0.51), whereas Dissolved Oxygen (DO) and Total Suspended Solids (TSS) exhibit a negative correlation with fish production (r = -0.65 and -0.57, respectively). These findings underscore the crucial role of mangrove ecosystems in supporting fishery productivity. Therefore, strengthening mangrove conservation efforts is essential to maintaining ecosystem balance and ensuring the sustainability of fishery resources.
Copyright (c) 2025 Adityo Raynaldo, Robin Saputra
Identifikasi Spesies Ikan Pembersih pada Pari Manta Karang (Mobula alfredi) di Cleaning Stations Manta Sandy, Selat Dampier, Raja Ampat
Cleaner fish are specialized fish species that coexist with other marine organisms by removing parasites and debris from their bodies. These fish play a crucial role in maintaining the health of various marine species, including reef manta rays (Mobula alfredi). However, a limited understanding of their interactions presents a significant challenge in marine conservation. This study aims to identify the species of cleaner fish that interact with reef manta rays (M. alfredi) at Manta Sandy, Dampier Strait, Raja Ampat. A modified camera trap method was employed, utilizing three GoPro cameras strategically placed at different locations within the study site. Data collection was conducted over 14 days in February 2023 to document cleaner fish interactions with reef manta rays. The findings revealed the presence of three cleaner fish species at the Manta Sandy Cleaning Station: Labroides dimidiatus, Thalassoma lunare, and Chaetodon kleinii. This study highlights the diversity of cleaner fish species at Manta Sandy, contributing valuable insights into their ecological roles and conservation significance. The findings serve as a crucial reference for future research on marine biodiversity conservation in Raja Ampat and surrounding regions.
Copyright (c) 2025 Nur Laila Lathifah, Mochamad Iqbal Herawata Putra, Muhammad Izuan, Ronald Mambrasar, Linuz, Orgenese, Riyanti Riyanti
Estimasi Kesuburan Perairan Teluk Lampung berdasarkan Vertically Generalized Production Model (VGPM)
Lampung Bay is an important water crossing in South Sumatra that is greatly influence by anthropogenic activities and oceanographic characteristics. This study characterized and estimated the spatial and temporal Primary Productivity (PP) in the three sections of the bay: head, middle, and mouth. The PP was modeled by using Sea Surface Temperature (SST), chlorophyll-a, Primary Productivity, and Photosynthetically Active Radiation (PAR) collected from remote sensing data and field measurements. Primary productivity was modeled with a Vertically Generalized Production Model (VGPM), and data validation was done using the Root Mean Square Error method. The distribution of PAR in Lampung Bay ranged from 35–52.50 E/m2/day. The distribution of SST ranged from 28.5–31.50°C. The highest distribution of chlorophyll-a was at the hHead of the bay with a range of 0.30-12 mg/m3. Correlation analysis shows that chlorophyll-a had the highest influence on PP (R2=0.99). While the middle and outer areas of the bay have a low average with values of 122.65 and 101.84 gC/m2/year. Our models show that there is high primary production at the Head of the bay, reaching eutrophic and mesotrophic levels. The middle and outer areas of the bay show productivity levels corresponding to mesotrophic and oligotrophic levels.
Copyright (c) 2025 Mochamad Tri Hartanto, Muhammad Riza Hanief Febrianto, Santi Susanti, Dea Fauzia Lestari, Tri Prartono, Rastina, Irzal Effendi, Stepahnie J. Martinez, Nurul Hidayah Mat Zaki
Peluang Bisnis dan Sumber Gizi Hewani dari Perikanan Produk Ikan Tangkap Lestari Kabupaten Buton Utara
Indonesia's capture fisheries hold significant potential to boost the seafood industry and reduce stunting, which affected 21.6% of children in 2022. Low consumption of marine-derived animal protein, averaging less than 10 grams/day, contributes to this public health issue despite an annual fishery potential exceeding 10 million tons. This untapped resource presents opportunities to process species like skipjack and tuna to meet local needs and global demand, which reached 180.07 million metric tons. This review highlights North Buton’s fishery resources as a driver of economic and nutritional value. Developing processed seafood products for local and international markets requires compliance with food safety standards and regulatory guidelines. Collaboration among government bodies, researchers, fisher groups, and NGOs is essential to design sustainable programs and address sectoral challenges. Adopting sustainable fisheries management — emphasizing selective fishing and Optimum Sustainable Yield (OSY) — preserves marine resources while benefiting communities. Implementing Indonesian National Standards (SNI) in post-harvest processes can improve product quality, extend shelf life, and elevate economic returns, supporting national goals to enhance nutrition and public health.
Copyright (c) 2025 Lestari Octavia, Cokorda Prapti Mahandari, Intan Ria Nirmala, Wiralis
Sebaran Spasial Plankton dan Klorofil-a sebagai Indikator Penentuan Daerah Potensial Penangkapan Ikan di Perairan Gili Trawangan
A high abundance of plankton serves as an indicator of water fertility and can be used to identify potential fishing grounds. Fishing grounds are determined by analyzing the presence and density of fish schools in a given area. This study aims to assess the spatial distribution of phytoplankton, zooplankton, and chlorophyll-a to identify potential fishing zones. The research was conducted in March 2024 in Gili Trawangan, covering 12 sampling stations. Sampling locations were selected using a purposive sampling method based on water characteristics, prioritizing areas with high plankton and chlorophyll-a concentrations. The results indicate that the southern waters of Gili Trawangan, particularly Stations 03 and 05, have strong potential as fishing zones due to their high phytoplankton, zooplankton, and chlorophyll-a concentrations. Similarly, Station 09 in the eastern waters exhibits the highest abundance of all parameters; however, its proximity to the harbor makes it unsuitable for fishing activities. Overall, Gili Trawangan meets the criteria for a viable fishing ground due to the high abundance of plankton species, which serve as a primary food source for fish. The dominant plankton species in these waters include Coscinodiscus sp., Rhizosolenia sp., and Nauplius sp.. A higher plankton abundance correlates with increased water productivity, leading to greater fish availability in these waters.
Copyright (c) 2025 Chandrika Eka Larasati
Analisis Kelayakan Air Laut untuk Wisata di Pantai The Legend-Pamekasan Berdasarkan Kelimpahan Bakteri Escherichia coli dan Konsentrasi Bahan Organik Total
The Legend Beach-Pamekasan is a tourist destination surrounded by five monitoring stations, where contamination by Escherichia coli bacteria has been detected. This bacterium can proliferate rapidly in aquatic environments when sufficient nutrients, particularly total organic matter, are present. Therefore, this study aims to assess the suitability of The Legend Beach-Pamekasan for tourism based on E. coli abundance and to analyze the relationship between total organic matter concentration and E. coli abundance at the study site. Bacterial abundance was determined using the membrane filtration method following ISO 9308-1:2014, while total organic matter content was analyzed based on SNI 06-6989.22-2004. The results indicate that E. coli abundance at Station 7 (The Legend Beach-Pamekasan) falls within the safe threshold for recreational beach use at 30 CFU/mL. However, swimming and snorkeling activities are not recommended in the surrounding waters, as E. coli levels at Station 1 (estuary) and Station 3 (fish-washing waste area) exceed the quality standard threshold established by Republic of Indonesia Government Regulation No. 22 of 2021. A significant correlation was found between total organic matter concentration and E. coli abundance across all stations (ρ = 0.01, p < 0.05). These findings highlight the need for effective waste management strategies in the area to prevent further contamination and ensure the long-term sustainability of The Legend Beach-Pamekasan as a safe and viable tourism destination.
Copyright (c) 2025 Eka Nurrahema Ning Asih, Annisa Ramadhanti, Ashari Wicaksono
Identifikasi Variabilitas Suhu Permukaan Laut dan Klorofil-a Lombok Strait pada Triple-Dip La Niña 2020-2022
The La Niña phenomenon often causes significant changes in sea surface temperature and deep-sea ecosystem dynamics in the context of global climate change. This study focuses on the impact of the 2020–2022 Triple-Dip La Niña in the Lombok Strait, which potentially affects maritime biological equilibrium. The research aims to identify and understand the variability of Sea Surface Temperature (SST) and chlorophyll-a concentrations during the Triple-Dip La Niña period. The study utilizes Sea Surface Temperature (SST) and chlorophyll (chlor_a) data from the Aqua-MODIS satellite, as well as wind direction and speed data in the form of Windrose diagrams in Mataram, West Nusa Tenggara, from 2020 to 2022, with a three-month interval to examine the variability in SST and chlorophyll-a concentrations. Statistical approaches, including correlation coefficient calculations, were applied to determine the relationships between variables. It was found that the highest temperature occurred in 2020, while the highest chlorophyll-a concentration was also recorded in the same year, particularly in coastal areas where the sea surface temperature was relatively lower than the surrounding areas. The results indicate a weak correlation between chlorophyll-A and SST in the Lombok Strait region.
Copyright (c) 2025 Daniar Ihza Daniar, Bima Arzhida, Putu Widya Novitarini, Imma Redha Nugraheni
Estimation of Total Suspended Solids in the Ujung Pangkah Estuary Using Multi-Temporal Sentinel-2 Satellite Imagery
The presence of dissolved materials in seawater, particularly Total Suspended Solids (TSS), significantly affects its optical properties. This phenomenon can be quantitatively observed through remote sensing techniques, which require various algorithms to convert pixel reflectance values into TSS concentrations. This study has two primary objectives: (1) to estimate and map TSS concentrations using multitemporal Sentinel-2 satellite imagery and (2) to compare multiple TSS estimation algorithms by analyzing satellite-derived data against in situ measurements. Sentinel-2 images from 2020 to 2022 were utilized, and TSS concentrations were derived using the Liu, Budiman, and Prasetyo algorithms. The satellite-derived TSS values were validated against field measurements from 25 sampling points. Accuracy was assessed using Root Mean Squared Error (RMSE) and Mean Absolute Percentage Error (MAPE). In situ measurements indicated that TSS concentrations in the study area ranged from 24 to 127 mg/L. The Liu and Budiman algorithms exhibited the highest standard deviation in TSS estimates, while the Prasetyo algorithm demonstrated lower deviations, yielding more reliable results. Statistical validation confirmed that the Prasetyo algorithm provided the most accurate estimation of in situ TSS concentrations (RMSE = 10.75, MAPE = 3.97%, R² = 0.85). These findings highlight the effectiveness of remote sensing for TSS monitoring and underscore the importance of selecting appropriate algorithms for accurate water quality assessment.
The Impact Shoreline Modifications on Lekang Turtle (Lepidochelys olivacea) Conservation Along Coastal of Kulonprogro, Indonesia
Changes in oceanographic circumstances that continue to occur will generate challenges for coastal ecology, one of which is a change in the sea-land boundary. It is possible to have an impact on the olive ridley turtles that rise to lay their eggs by changing the region of this coastal area, particularly at Trisik Beach, Kulonprogo, and Yogyakarta Special Region. The goal of this study was to use a Geographic Information System to estimate the effect of changes in the coastline on the distribution of olive ridley turtles on Trisik Beach, Kulon Progo, and Yogyakarta Special Region in 2020-2022. Digitizing the shoreline reveals changes in the coastline, which is then analyzed using Landsat 8 satellite data retrieved with ArcGIS software. The Landsat 8 photos span the years 2020-2022. Using the Digital Shoreline Analysis System (DSAS) toolbox, each image will go through area cropping or image cutting, geometric and radiometric correction, demarcation or development of a land-sea boundary line, on-screen digitalization, and automatic calculation of coastal changes. Trisik Beach's coastline alterations from 2020 to 2022 tended to create abrasion due to the shrinking beach area. The greatest average distance to a coastline alteration was -29.61 m, the smallest was -15.03 m, and the average speed of the greatest abrasion is -8.26 m/year, the smallest is -4.19 m/year, resulting in a 111,967.03 m2 reduction in coastal area. The association between shoreline alterations and the distribution of olive ridley turtle nesting on Trisik Beach is quite significant, with the beach area affecting 91.3% of turtle nests and 88.5% of turtle eggs.
Distribusi Bahan Organik dan Fraksi Sedimen di Perairan Teluk Lampung
Sediment deposition in waters is considerably influenced by coastal processes causing variations in their physical and chemical characteristics. This study reveals the size composition of sediments and organic matter in Lampung Bay sediments how deposition processes occurAnalysis of the sediment fraction was carried out based on the American Society for Testing and Materials (ASTM) standards D422-63, while the organic matter was carried out using the loss on ignition (LOI) method. The silt sand fraction (75.95-78.73%) and clay fraction (18.27-20.28%) have a higher percentage than the sand fraction (3.00-3.81%). Then, the organic content in the sediments of Lampung Bay waters ranges from 10.67-13.48%. The distribution of sediment and organic matter fractions in the waters of Lampung Bay was not significantly different between stations, which means that stations near the head of the bay (TL 1 and TL 2) had a percentage of sediment and organic matter fractions that were not significantly different from stations in the middle or towards the mouth of the bay (TL 3-TL5).
The Economic Analysis of Fisheries Management of Big Pelagic Fish in WPPNRI 715
Fisheries management is essential in striving for fish resources to be utilized optimally and sustainably and have a welfare impact. WPPNRI 715 is one of Indonesia's eleven fisheries management areas with the most significant potential in big pelagic fish with high economic value. The aim of this study was to estimate the economic value in the management of large pelagic fisheries in WPPNRI 715. The result of the research can show utilization of big pelagic fish in WPPNRI 715 is good condition and has not exceeded the Maximum Sustainable Yield (MSY) value. Additionally, economically the benefits are still in good condition. The optimal production (MSY) of big pelagic fish in WPPNRI 715 is 421 872, 11 tons. Maximum profit MEY is Rp3 065 588,97 trillion with the actual effort of 470 609 trips where optimal effort is sustainable (MSY) of 861 131 trips and economically optimal effort (MEY) of 554 902 trips. Based on the results of the study, it was stated that there were economic benefits in the utilization of large pelagic fish resources in WPPNRI 715.
Analisis Kualitas Garam Lokal di Kabupaten Aceh Timur Dengan Berbagai Metode Pengolahan Garam
Salt is one of the local commodities produced by the people of East Aceh District. This salt is widely utilized as an additive substance in the processing of various commodities, including fish preservation and the production of “asam sunti”. The quality of salt is greatly influenced by the concentration of seawater and their processing method. The purpose of this study was to examine the effect of production salt processing methods on the quality of the salt produced and to compare the results of analysis with SNI for consumption of iodized salt. The method used in this study is a comparative research method, which compares the quality parameters of salt produced by geomembrane (G1), boiling (G2) and a combination both of them (G3). The quality parameters analyzed were water content, NaCl content, iodine content, and water insoluble portion. The results of analysis compared with the standard SNI 3556: 2016 Concerning Iodized Consumable Salt show that the water content in G1, G2, G3 is 0, 7, and 6,4 respectively, the NaCl level in G1, G2, G3 is 120, respectively. 51, 10.98, 12.29, the water insoluble portion in G1, G2, G3 was 2, 4, 2,5 respectively and the iodine content in G1, G2, G3 was 34,65, 42,49, 47,46 respectively, so it can be concluded that geomembrane production method has better salt quality compared to the boiling production method and a combination of the two. NaCl levels and iodine levels produced through the production of geomembranes have reached the established standards SNI 3556:2010 concerning Iodized consumption salt.
Strategi Pengembangan Ekowisata Mangrove Berbasis Daya Dukung Kawasan di Kelurahan Oesapa Barat Kecamatan Kelapa Lima Kota Kupang
Mangrove ecotourism in West Oesapa village is ecotourism located in a densely populated area, so if this ecotourism is not managed properly it will have fatal consequences for the mangrove ecosystem. This research aims to determine the suitability of mangrove ecotourism resources and also the carrying capacity of mangrove areas as well as the development strategies so that they can be taken into consideration by stakeholders in making future management policies for mangrove ecotourism. The data collection method was carried out by direct observation, interviews and also collecting data from previous research conducted in the research area, then to formulate a strategy for developing mangrove ecotourism using SWOT analysis. The results of the data analysis of the suitability of mangrove ecotourism resources are at a level corresponding to a value of 2.24 with the number of visitors in the ecotourism area according to the calculation of the area's carrying capacity of 84 people per day with an operational time of the tourist area of ​​8 hours per day. The direction for developing mangrove ecotourism is to implement a diversification strategy, meaning using existing strengths to take advantage of long-term opportunities to cover weaknesses (threats).
Estimasi Simpanan Karbon Organik pada Ekosistem Mangrove di Desa Mojo, Kecamatan Ulujami, Pemalang
The mangrove ecosystem as a coastal ecosystem is important in reducing the impact of climate change, especially in absorbing CO2 gas. The mangrove forest in Mojo Village, which had the largest area in Pemalang Regency, was not only threatened by coastal erosion but also faced deforestation for shrimp pond development. Considering the high ecological function of mangroves in climate change mitigation, it was essential to calculate carbon storage estimates in this ecosystem. The methodology employed in this study involved a survey method to analyze ecological indices and estimate carbon sequestration in mangrove biomass and sediments. The Importance Value Index indicated that the Avicennia alba mangrove species exhibited higher density and canopy coverage compared to the other three found species: Sonneratia caseolaris, Avicennia marina, and Rhizophora mucronata. The high density and canopy coverage of Avicennia alba made it the mangrove species with the highest estimated carbon biomass content. The estimated carbon storage in mangrove biomass at the research site ranged from 21.55 to 144.22 tons C/ha, while the estimated carbon storage in mangrove sediments varied from 98.45 to 181.06 tons C/ha. The total carbon storage estimate in the mangrove ecosystem of Mojo Village, Pemalang, ranged from 112.43 to 247.98 tons C/ha, with an average of 155.13 tons C/ha
Spatial and Temporal Variation of Zooplankton Composition Near Whale Shark Sightings in Probolinggo of East Java, Indonesia
Whale shark occurrence in Probolinggo differs from other Indonesian locales, suggesting a link to zooplankton availability. Zooplankton composition and whale shark emergence are the focus of this study. From December 2017 to November 2018, six observation points were made each month. A plankton net filters and lugol preserves water. Olympus CX23 microscope observations were repeated twice. The spatial analysis revealed varying whale shark numbers at each station (Chi-square test, X2 = 1418.6, P <0.05), with six sharks observed at station PR_5. Zooplankton numbers were similar at each location. Temporal analysis revealed significant differences in whale shark appearance each month (Chi-square test, X2 = 81.04, P <0.05), with March and November having the highest appearance among the three individuals. The amount of zooplankton varied (Chi-square test, X2 = 148.61, P <0.05), with the highest abundance in April and March. Whale shark appearance and zooplankton composition were not correlated (r = 0.01, P< 0.05) both geographically and temporally. Whale sharks were linked to zooplankton kinds. Results indicate whale sharks are particularly interested in Acartia sp. (r = 0.3, P < 0.05). This suggests that whale sharks' appearance is determined by their demand for food, not zooplankton availability.
Tidal Characteristic Analysis Utilizing Radar Tide Gauge in Cirebon Seawater
Radar-based tide gauges are one approach in measuring water level offering easier installation and maintenance. Tidal data recording that has been done commonly applies tide staff or pressure tide gauge. In this study, a radar tide gauge was installed at Cirebon port, northern part of Java island, to determine the tidal characteristics in Cirebon seawaters. Water elevation data was recorded every 15 minutes from July 2022 to November 2023. The tidal component is calculated using least squares method while the tidal type is determined using the Formzahl number. The dominant tidal component known consists of semidiurnal component i.e. M2, S2, N2, K2, 2N2; diurnal component, K1, O1, P1, Q1, J1, TAU1; and shallow water component SSA components with a height of 11.98, 5.58, 2.91, 2.11, 1.45, 11.80, 3.89, 6.11, 2.08, 1.56 and 3.11 (in cm), respectively. Tidal type in the study area is mixed type prevailing Semidiurnal. The tidal range is around 0.8-1 m high with high tide conditions at 6.00-9.00 and 18.00 - 21.00, while low tide conditions are within 11.00 - 14.00 and 01.00 - 04.00. Elevation height calculation based on datum is done by combining the tidal components. Tidal measurement data using radar can be an alternative data to support and complement data recorded in Cirebon and may become a consideration for development and other maritime activities.
Analisis Stok Rajungan (Portunus pelagicus) di Laut Jawa Bagian Utara Kabupaten Tegal dan Strategi Pengelolaannya
Tingginya nilai ekonomis rajungan dalam perekonomian mendorong peningkatan penangkapan di alam sehingga memicu terjadinya overfishing. Pendugaan stok rajungan di Kabupaten Tegal sangat minim dilakukan karena kurangnya informasi data mengenai rajungan. Penelitian ini bertujuan untuk mengetahui karakteristik dan kondisi stok rajungan (Portunus pelagicus) di Perairan Laut Jawa, Kabupaten Tegal. Pengambilan sampel sebanyak 715 ekor dari nelayan, pengepul rajungan di Desa Suradadi, Bojongsana dan Purwahamba. Dilakukan dengan menggunakan metode sampel acak (Simple Random Sampling). Sampel yang didapat dilakukan pengukuran lebar karapas dan berat tubuh rajungan. Analisis data secara manual dan menggunakan bantuan software FISAT II dikeluarkan oleh FAO-ICLARM. Diantaranya sebaran frekuensi lebar karapas, hubungan lebar berat, pola pertumbuhan, mortalitas dan laju eksploitasi serta pola rekrutmen rajungan (Portunus pelagicus). Hasil penelitian ini adalah karakteristik rajungan di Kabupaten Tegal penangkapannya menggunakan bubu lipat, jenis yang banyak ditangkap jantan dengan ukuran lebar karapas 14 cm. Kondisi stok rajungan di Kabupaten Tegal masih dikategorikan baik sebab laju eksploitasi rajungan hanya sebesar 0,31 per tahun yang menunjukkan bahwa upaya penangkapan belum melebihi batas tingkat eksploitasi maksimal yaitu 0,5 per tahun. Upaya pengelolaan rajungan di Kecamatan Suradadi, Kabupaten Tegal yaitu strategi pengelolaan perikanan rajungan di perairan Kabupaten Tegal meliputi menetapkan pengelolaan perikanan rajungan dalam Peraturan Daerah dan sosialisasi kepada stakeholder terkait.
Jenis dan Komposisi Sampah Laut di Pesisir Randusanga, Brebes, Jawa Tengah
The problem of plastic waste in Indonesia is considered an emergency status, following research results that place Indonesia as the largest contributor to marine plastic waste in the world after China. The lack of information about marine pollution on the coast is a problem in its handling, especially in Brebes Regency, Central Java. This study aims to identify the types of marine debris and estimate their composition and distribution on the coast of Randusanga Brebes Beach. Marine debris sampling was carried out using the quadrant transect observation method which was carried out three times with a total of 15 transects in August-October 2021. Data was analyzed using Graphical Data Analysis (GDA) approach. Of the various types of waste found, plastic waste was the most dominant waste found with 869 items, followed by 190 items of plastic foam, 57 items of paper and cardboard, 48 items of wood, 36 items of rubber, 34 items of other materials, 22 items of metal, 8 items of cloth, as well as glass or ceramic as much as 4 grains. Based on size, macro-sized waste is the most commonly found waste. The total amount of macro debris found at the study site was 1,222 items, while the meso debris was 66 items. Percentage composition of tents: plastic bags (71%), plastic foam (15%), fabrics (4%), glass and ceramics (0%), metal (0%), paper and cardboard (4%), rubber (0%) , wood (2%), other materials (4%). Types of plastic waste based on the Resin Indetification Code (RIC) consist of polypropylane (PP), low density polyethylene (LDPE), others (OT), polystyrene (PS), high density polyethylene (HDPE), polyethylene terephthalate (PET/PETE) waste. The high abundance of marine debris every month is closely related to the lack of public awareness of the sustainability of the surrounding ecosystem and the lack of awareness of the implementation of Government Regulations regarding the handling of applicable waste.