Coral reef ecosystems are vital for marine biodiversity, coastal protection, and local livelihoods, yet environmental and anthropogenic stressors increasingly threaten them. Accurate and timely mapping of these habitats is essential for effective management and conservation planning. This study aims to evaluate and compare the spatial distribution and extent of coral reef habitats around Liang and Rakit Islands, as well as to assess the classification accuracy of Sentinel-2 Level-2A and the SPOT-7 satellite imagery for the years 2016 and 2021. Both datasets were pre-processed through atmospheric and sun-glint corrections, with SPOT-7 imagery further enhanced by water column correction using the Lyzenga algorithm. Supervised classification in ENVI was used to map four shallow-water habitat classes (coral reef, seagrass, sand, and rubble), and classification accuracy was assessed using confusion matrices to compute Producer Accuracy (PA), User Accuracy (UA), and Overall Accuracy (OA). Across both islands, coral reef and seagrass each occupied roughly one quarter of the mapped shallow-water area, while sand and rubble together accounted for about half of the area, indicating a heterogeneous mosaic of fringing reefs and seagrass meadows interspersed with sandy and rubbly substrates. Maps derived from SPOT-7 imagery produced higher overall accuracies (84% for Liang and 82% for Rakit) than those derived from Sentinel-2A imagery (76% and 70%, respectively). SPOT-7-based classifications consistently delineated larger and more detailed extents of coral reef and seagrass habitats, demonstrating the value of higher-resolution imagery for representing fine-scale features in optically complex coastal environments, whereas Sentinel-2A imagery was more suitable for broad-scale habitat discrimination but tended to underestimate narrow or fragmented patches.

Milkfish deaths (Chanos chanos) that occur suddenly during the enlargement phase in ponds are multifactorial; therefore, an analytical approach is needed that can simultaneously evaluate the relationships among various environmental factors. This study aimed to analyze the influence of environmental factors, including pond water quality and sediment, total Vibrio harveyi levels, the presence of toxic phytoplankton, heavy metal content, and residues of pesticide active ingredients, on the sudden death of milkfish. Water, sediment, and milkfish samples were collected from ponds that experienced sudden fish deaths during the enlargement phase. The water quality parameters analyzed included NH3-N, total suspended solids (TSS), PO4-P, NO2-N, NO3-N, TOM, C-organic, total nitrogen, and total phosphorus. The characteristics of the sediments analyzed included pHF, redox potential, organic carbon, organic matter, total nitrogen, and PO4. Other parameters analyzed included total Vibrio counts, identification of toxic phytoplankton, and pesticide residues. The data were analyzed using multivariate methods, namely, principal component analysis (PCA) and cluster analysis, to identify the dominant factors contributing to milkfish mortality. The results showed that milkfish morphology and histology strongly indicated environmental pollution. This was supported by the fact that all water quality parameters, except TSS, exceeded milkfish tolerance limits. In addition, the characteristics of the sediment indicated unnatural conditions, the presence of toxic phytoplankton Harmful Algal Blooms (HABs), high concentrations of heavy metals Pb and Cr, and the identification of four active ingredients of pesticides. The accumulation of these factors has been shown to significantly contribute to milkfish mortality in ponds.

This research examines the potential of integrated land-sea spatial planning as a strategic approach to disaster risk reduction in Tanah Laut Regency, South Kalimantan province, Indonesia. Specifically, it aims to (a) assess spatial overlaps between terrestrial-marine land use patterns and hazard zones, (b) evaluate coastal typologies and their corresponding vulnerabilities, and (c) formulate subdistrict-specific spatial planning recommendations to enhance regional resilience. A mixed methods design was adopted combining quantitative spatial techniques and qualitative descriptive analysis. Disaster potential in coastal regions is examined through an integrated assessment of terrestrial disaster risks and marine-based coastal vulnerability index (CVI) analyses. Terrestrial disaster susceptibility was assessed by using the Regional Development Planning Agency's 2021 disaster risk assessment, while coastal vulnerability was evaluated by using CVI parameters and overlaid with terrestrial and marine spatial planning categories. The spatial analysis shows a strong convergence between high terrestrial disaster risk and land use categories associated with intensive human modification-notably, food crop agriculture (23,610.53 ha), plantations (19,718.99 ha), aquaculture, and urban and rural settlements. Protected areas such as mangrove ecosystems, wildlife reserves, and natural tourism parks are located in high-risk coastal belts, while parts of marine conservation reserve areas and capture fisheries areas fall within high and very high CVI classes. Land rights overlays demonstrate that high tidal flood risk coincides with ownership rights and unregistered parcels. Overall, the research demonstrates that sustainable coastal development in Tanah Laut Regency cannot be achieved by treating land and sea as separate planning arenas. Risk-sensitive, typology-based integration of terrestrial and marine spatial plans-as supported by ecosystem-based zoning, mangrove restoration, relocation from high-risk zones, and strengthened marine conservation and fisheries management-is essential to enhance disaster resilience and long-term spatial sustainability in Tanah Laut Regency.

Inter-country sales of ornamental fishes are one of the ways non-native and invasive fishes enter an aquatic ecosystem. This contributes greatly to the distribution and abundance of native fishes in the aquatic ecosystem. The aim of this study is to collect and identify quantitative baseline data on some information of ornamental fish species sold in ornamental fish shops in Kupang City. Results showed that there were 46 species recorded during the study and only 20% (n=9) of the species were native Indonesian species and 80% (n=36) of the species were non-native (1 hybrid species). In addition, it was recorded that 7% (n=3) of the total fish sold in Kupang City were invasive species. The invasive species were Carassius auratus, Xiphophorus helleri and Poecilia reticulata. These three species are included in the 80% nonnative species.

BACKGROUND AND OBJECTIVES: Choosing a location for mariculture is very important because it affects water quality, while problems that affect cultivation and the environment can be avoided by choosing the right location. The objective of this study is to develop a methodological strategy for integrating and analyzing spatial data, which will facilitate the identification of optimal locations for mariculture. In this context, the ecosystem approach to mariculture is analyzed with an emphasis on evaluating water quality conditions and determining primary productivity values.METHODS: Water quality parameter data was analyzed using principal component analysis, values, and distribution of primary productivity using the kriging interpolation method using geographic information system. Spatial analysis employing Geographic Information System applications is used to evaluate the appropriateness of locations for mariculture.FINDINGS: The distribution pattern of primary productivity is strongly influenced by the distribution of phytoplankton and the highest concentration values are located in coastal waters and small islands. The analysis identified three primary components that account for 79.64 percent of the results. The most influential factors include suspended particulate matters, nitrate, temperature, salinity, ammonia, current, and water transparency. According to the study results, the principal component values indicate that the most affected regions by pollutant pressure are agricultural lands that drain into rivers and watersheds, along with coastal residential neighborhoods.CONCLUSION: The status of water quality is the main limiting factor in determining the location of mariculture, therefore it is necessary to relocate existing mariculture, improve agricultural cultivation techniques, and/or regulate the use of pesticides that not carried out during the rainy season. These findings may assist the appropriate authorities in the selection and oversight of mariculture sites. The innovative aspect of this study lies in its focus on adaptive management of sustainable marine cultivation, designed to align with regional conditions and promote ecological health alongside the socio-economic prosperity of local communities.

Intensive technology of whiteleg shrimp (Litopenaeus vannamei) aquaculture generates wastewater that, if not properly managed, can adversely affect the long-term viability of brackishwater pond aquaculture and threaten environmental sustainability. This study evaluates the performance of wastewater treatment plant (WWTP) associated with this intensive whiteleg shrimp aquaculture. Wastewater samples were collected from various locations: the reservoir, grow-out pond, WWTP inlet, WWTP, WWTP outlet, and the sea, at four stages of shrimp growth (15, 45, 75, and 105 days of culture (DOC)). Key variables analyzed included temperature, salinity, pH, dissolved oxygen (DO), ammonia (NH3), nitrate (NO3), nitrite (NO2), phosphate (PO4), total organic matter (TOM), biochemical oxygen demand 5-day (BOD5), and total suspended solids (TSS). Data from the WWTP inlet and outlet were used to assess removal efficiency (RE) and calculate compliance index (CI) values for evaluating WWTP performance. The Storage and Retrieval (Storet) system was used to evaluate the wastewater quality status. The results indicated that the WWTP utilized constructed wetlands with a hydrological design that included both surface and subsurface flow. On the culture of 105 DOC, the concentrations of NH3, NO3, and PO4 at the WWTP outlet surpassed the threshold for marine and brackishwater aquatic life. However, the levels of pH, DO, NO2, TOM, BOD5, and TSS were within the acceptable range for marine and brackishwater aquatic life. The WWTP covered 9.51

Brackish water is often contaminated with dangerous and toxic pollutants, such as heavy metals, microplastics, and polyaromatic hydrocarbons. Bioremediation methods using nonpathogenic bacteria can be applied to remove these pollutants. This research aims to eliminate lead pollutants in the cultivation media for tiger shirmp of the type Penaeus monodon (TSPM), while increasing daily growth. Engineering cultivation media with the addition of Bacillus pumilus (BP) and Pseudomonas stutzeri (PS) bioremediators to remove Pb2+ pollutants in TSPM media. The maintenance process lasts for 30 days. The effectiveness of the method is determined by measuring the physical and chemical properties, growth analysis, and survival rate of TSPM. The bioremediation performance of the bioremediator bacteria was determined using the Atomic Absorption Spectrophotometer instrument. The research results showed that all physical and chemical parameters of the cultivation media analyzed met quality standards. The presence of BP and PS remediation bacteria did not have a negative effect on TSPM growth. The survival rate of TSPM was relatively higher than in conventional shrimp cultivation. The bioremediation performance of BP bacteria is superior to that of PS bacteria and a mixture of BP+PS bacteria in removing lead pollutants. This bioremediation method is suitable for application to other crustacean cultivation.

Understanding the spatiotemporal dynamics of water quality and its influence on phytoplankton communities is vital for effective coastal management. This study investigated the relationship between phytoplankton community structure and key water quality parameters to evaluate their potential as environmental health indicators in Parepare Bay, Indonesia. We analyzed comprehensive water quality parameters, including key nutrients (N and P forms), and phytoplankton composition across wet, transitional, and dry seasons, using multivariate statistical and spatial analyses. The study confirms that phytoplankton serve as robust spatiotemporal bio-indicators of water quality, particularly distinguishing estuarine and less freshwater-influenced areas. Salinity and NO2 were consistently identified as primary overall drivers (ρ ≥ 0.744). Seasonally, high freshwater runoff resulted in high N/P ratios and stratification, favoring motile dinoflagellates and making NO3 a key wet-season driver. Conversely, pH, NH3, and PO4 dominated the dry season (ρ ≥ 0.634), indicating shifts to nutrient-limited conditions and localized organic accumulation that favored diatom richness. Critical ecological findings include the consistent presence of stress-tolerant Oscillatoria sp. and the proliferation of the heterotrophic Protoperidinium sp. near the river mouth, highlighting an immediate need to assess the risk of harmful algal blooms (HABs). Given the pervasive localized influence of aquaculture, implementing Integrated Multi-Trophic Aquaculture (IMTA) through integrated seaweed cultivation is proposed as a validated, effective bioremediation solution. These findings underscore the critical need for zone-specific, seasonally adaptive coastal management to ensure the long-term sustainability of Parepare Bay and provide vital insights for comparable tropical coastal systems.

The agricultural activities in rice-farming system can have an impact on fish farming and the characteristics of bacterial community, especially pathogenic bacteria. Utilization of probiotics as environmentally friendly biotechnology products can be used to improve environmental quality and suppress the presence of pathogenic bacteria. This study aimed to select bacteria as probiotic agents from aquaculture ponds with the Rice-fish farming system. A total of 22 bacterial isolates were isolated from the water and sediment contained in the culture ponds. Based on the screening results, 15 isolates were confirmed as general non-pathogenic bacteria (Aeromonas sp.), 9 isolates had antibacterial activity against Aeromonas hyrophylla and 4 isolates showed high antibiotic sensitivity and were able to synergize. The results showed the Proteus mirabilis, Proteus penneri, Kurthia gibsonii and Bacillus cereus strains. Bacillus cereus strain LB8 has antibacterial activity that can inhibit the pathogen Aeromonas hydrophila with an inhibition zone of 8mm and has a very high sensitivity to antibiotics. These four isolates are able to work together synergistically and can be used as consortium probiotic bacterial agents to suppress the growth of pathogens.

Intensive technology Pacific white shrimp (Litopenaeus vannamei) culture has been applied in Bulukumba Regency, South Sulawesi Province, but information on the performance of Pacific white shrimp culture and the land characteristics or environment of the pond has not yet been obtained. The research purposes are to find out the performance and the land characteristics or environment of Pacific white shrimp culture intensive technology to serve as a basis for determining the culture development. Five transects perpendicular to the shoreline and three transects parallel to the coastline, or 15 water sample stations, were identified in the field. Other data was obtained from the extraction of Sentinel-2 and SPOT (Satellite pour l’Observation de la Terre) satellite imagery 7. The size of intensive technology Pacific white shrimp culture ponds in Bulukumba Regency ranges from 1600 to 5000 m2 which is stocked with fry with a stocking density of 100–300 ind./m2 which can produce 12.0–50.0 tons/ha/cycle after rearing for 100–142 days of culture with a food conversion ratio of 1.2:1–2.0:1. The land characteristics of intensive technology Pacific white shrimp culture ponds in Bulukumba Regency are characterized by elevation from 10.0 to 20.0 m above sea level, wavy topography, tidal range between 1.35 and 1.70 m, dominated by Latosol or Cambisol and Alfisol or Mediterranean soil great groups, the quality of the source water can generally support Pacific white shrimp culture, and the annual rainfall is from 1341 to 1763 mm and it is not built on former mangrove land. It is recommended that existing Pacific white shrimp culture ponds increase the capacity and capability of their wastewater treatment plant ponds and implement better water management and feed management so that the quality of wastewater from intensive technology Pacific white shrimp culture ponds can also be better so that productivity can be increased and sustainable.

The Fasin rainbow fish, scientifically named Melanotaenia fasinensis, is highly prized by aquarium enthusiasts for its vibrant colors and adaptability to artificial aquatic environments. This species is endemic to the karst landscape of the Bird's Head region in Papua, Indonesia, and belongs to the family Melanotaeniidae. Discovered relatively recently in 2010, this species was designated as endangered by the International Union for Conservation of Nature (IUCN) in 2021. However, there is currently insufficient data regarding its phylogenetic position. To address this gap, our study employed next-generation sequencing (NGS) to analyze the entire mitochondrial genome of M. fasinensis. The mitochondrial genome comprises 13 protein-coding genes, 22 transfer RNA genes, and two ribosomal RNA genes, with a total length of 16,731 base pairs. The base composition of the mitogenome revealed percentages of 27.76% adenine (A), 27.34% thymine (T), 16.15% guanine (G), and 28.75% cytosine (C) residues. Our phylogenetic analysis based on sequence data indicated that all species of the Melanotaeniidae family clustered together on the same branch. Furthermore, the intergeneric and interspecific taxonomic positions were explicit and clear. Phylogenetically, Melanotaeniidae were more closely related to the family Isonidae than to the family Atherinomorus. The phylogenetic position of M. fasinensis was relatively basal within the genus Melanotaenia. This study provides valuable molecular insights for further exploration of the phylogeography and evolutionary history of M. fasinensis and other members of the genus Melanotaenia.

This study primarily focuses on pollutant of Global trends in the Marine Ecosystems around the Spermonde Archipelagos. Contaminants known as Global Trenches Pollutants (GTP) are absent from healthy marine environments. When using marine resources for marine tourism, accuracy and prudence are required to avoid future ecological dangers that have a cascading effect on human health as well as aquatic ecosystems. The study identifies exposure to GTP: microplastics (MP), polyaromatic hydrocarbons (PAHs), heavy metal (HM), pesticide residue (PR), and medical waste (MW) in marine ecosystems the Marine Tourism Area (MTA) area and Barrang Caddi Island (BCI) waters. A combination of qualitative and quantitative analysis methods was used with a combination of analytical instruments and mathematical formulas. The search results show the average total abundance of MP in seawater and fish samples (5.47 units/m3) and (7.03 units/m3) as well as in sediment and sponge samples (8.18 units/m3) and (8.32 units/m3). Based on an analysis of the polymer structure, it was identified that the dominant group is MP, from polyethylene (PE), polypropylene (PP), and polystyrene (PS), followed by polyamidenylon (PA) and polycarbonate (PC). Several PAHs pollutants were identified in the samples. In particular, Naphthalene (NL) types were the most common in all samples, followed by pyrene (PN) and azulene (AZ). BCI sea waters are suspected to be exposed to MW and PR. Pb+2 and Cu+2 pollutants around BCI were successfully calculated, showing average concentrations in seawater of 0.164 mg/L and 0.294 mg/L, respectively, while in fish, concentrations were 1.8110 µg/g and 2,452 µg/g, respectively. Based on these findings, the BCI area is not recommended as a marine tourism destination. BCI is maintained as a marine tourism area, it is feared that its ecosystem will enter an ecological hazard state, which will have a chain effect, not only on the aquatic ecosystem around the BCI but also on the sponge populations and fish, leaving them unfit for consumption and subsequently causing health problems for the community.

In addition to having high economic value, catfish (Clarias sp.) can also be cultivated quickly and they can adapt well. The demand of catfish is in line with the increase in production which is expected to remain efficient and environmentally sound. Biofloc technology has also been implemented in catfish for increasing productivity. Biofloc utilizes the activity of heterotrophic microorganisms and autotrophs for the conversion of organic waste into floc and is used as fish feed. This study aims to examine the effect of the use of molasses with different doses (C/N ratio) on the growth and survival rate of catfish. This study was conducted with as many as 3 treatments with 3 repetitions each except for the control. The treatment with the ratio of molasses in each of them: A: C/N of 10:1; B: C/N of 15:1; C: C/N of 20:1, and D without molasses given as control. The study using 240 catfish measuring 10-12 cm was carried out for 30 days with sampling every 10 days. It aims to determine the average growth, daily growth, and survival rate of test biota during the study. Based on the results of this study, it can be concluded that the use of different doses of molasses in catfish farming, and biofloc technology will affect the growth and survival rate of farmed catfish. Catfish farmed with biofloc technology at a C/N ratio of 15:1 show the best results on their growth and survival rate. In addition, catfish farming with a biofloc C/N ratio of 15:1 has a better economic analysis when compared to conventional catfish farming. In summary, the use of biofloc based on research results can be a recommendation to be applied in the community, especially among catfish farmers.

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The Pacific white or vaname shrimp (Litopenaeus vannamei) can now be cultivated using superintensive technology with stocking densities of 300–1200 shrimp/m3 and yields up to 100 tons/ha. However, this technology can produce nutrient-rich waste containing 20–30

Abstract The widespread degradation of mangroves has been attributed to their conversion into other land uses and purposes, most notably their destruction to construct extensive brackishwater aquaculture ponds. This study investigated the relationship between environmental factors and management alternatives for an integrated mangrove-aquaculture system in Derawan Island District, Berau Regency, East Kalimantan Province, Indonesia. The study collected a total of 56 soil and water samples from around 50 ha to assess environmental limiting factors for the integrated mangrove-brackishwater aquaculture management. The measured soil quality variables included pHF, pHFOX, SPOS, FeS2, organic matter, nitrogen-total Fe, and Al. Water quality variables included salinity, temperature, pH, dissolved oxygen, NH3–ammonia, NO3–nitrate, NO2–nitrite, PO4-phosphate, Fe, and total organic matter. The study employed a hydrological restoration approach to suggest a mangrove-friendly aquaculture pond design and layout. The study generally showed that Acid Sulfate Soils (ASS) significantly restricted the existing mixed-mangrove aquaculture pond management by negatively impacting water quality. This study highlights that, given the characteristics of ASS-affected aquaculture ponds, reducing pond size for shrimp culture (mangrove-to-pond ratio of 80% and 20%) will simplify managing ASS environmental limiting factors through cost-effective remediation technique and a Balanced Fertilization Strategy (BFS). The reduced shrimp pond size will also provide direct opportunities for mangrove restoration and allow effective hydrological restoration. The economic benefit of the proposed pond design and management model focuses on diversifying production units which include shrimp aquaculture ponds, milkfish or tilapia culture in the peripheral canals of the mangrove compartment, juvenile shrimp production, and periodic harvest from the primary pond canal. The study findings are particularly applicable to ponds that have already been built in ASS to improve productivity in addition to supporting the mangrove rehabilitation program. Converting mangrove and ASS-affected land is not advisable for constructing new aquaculture ponds.

The integration of mangrove management with aquaculture, termed the silvofishery pond system, has been implemented in Berau Regency, East Kalimantan Province, Indonesia. A detailed survey was conducted to assess the features of mangrove terrain surrounding silvofishery ponds, aiming to enhance the productive and sustainable management of these mangrove areas in Berau Regency. This survey focused on various land characteristics such as topography, tidal patterns, water quality, soil properties, climate, and the state of mangrove vegetation. The health of mangrove vegetation was assessed by calculating the Important Value Index (IVI) across different growth stages: trees, saplings, and seedlings. The findings reveal that the mangrove adjacent to the silvofishery ponds in Berau Regency are home to 14 species from 13 genera and 10 families. Rhizophora mucronata displayed the highest IVI scores across all growth stages: 75.17% for trees, 93.14% for saplings, and 66.98% for seedlings, the latter shared with Rhizophora apiculata. Soil quality emerged as a critical limiting factor for land use in silvofishery ponds, particularly due to high potential acidity (low pH) and low nitrogen (N) content. To enhance soil quality, it is recommended that soil management practices such as remediation (via drying, submerging, flushing, or liming) and N supplementation through fertilization be employed. Furthermore, given the sparse mangrove vegetation density at the tree level (1,012 trees/ha), efforts to promote natural mangrove regeneration and prevent deforestation and degradation are advised. Considering the unique characteristics of the mangroves, the implementation of the komplangan model—a silvofishery approach that segregates mangroves restoration pond from grow-out ponds—is recommended to boost productivity and ensure sustainability in the coastal region of Berau

Whiteleg shrimp (Litopenaeus vannamei) culture with more advanced technology has been developed in the coastal regions of Southeast Asia, including Indonesia, to catch up with the increasing worldwide demand for shrimp. If left unchecked, the effluent from this high-density shrimp farming could have irreversible impacts on the receiving environment and the shrimp industry. This study was carried out to determine changes in water quality status before and post-development of the intensive whiteleg shrimp industry in the coastal area of Je’neponto, a regency located in the south of South Sulawesi Province, Indonesia. The water quality parameters were measured in situ and ex situ before the farming cycle started and after harvesting. Temperature, salinity, pH, dissolved oxygen, nitrate, nitrite, ammonia, and phosphate were measured using standardised methods. The data were statistically analysed using Kruskal–Wallis, Mann–Whitney, and principal component analysis. Water quality status was determined using the storage and retrieval approach. The potential for waste from the intensive whiteleg shrimp ponds was estimated at 7,408 kg of total nitrogen (TN) per cycle and 1,748 kg of total phosphorus (TP) per cycle. The study also found that the wastewater treatment plant pond was only about 1.45% of the total pond volume and is classified as a low-capacity wastewater treatment plant for intensive whiteleg shrimp farming. The water quality was classified in the class B category (good or slightly polluted) prior to the operation of the shrimp farm to class C (moderate or moderately polluted) afterwards.

Activities in the Minapadi fish farming ecosystem are closely related to the role of microorganisms, including degrading bacteria found in sediment.Therefore, in the short term, this research aims to determine the proportion and activity index of proteolytic bacteria isolated from the sediment of the mina rice cultivation system.Research is expected to find the best isolate as a probiotic agent which can be used in fish cultivation in the long run.The method used is observation.Sediment sampling was carried out using a purposive random sampling method in two ponds of the Minapadi fish cultivation system which have different characteristics.Sampling was taken at Block A and Block E, at each location 3 points were taken, namely inlet, middle and outlet.The results of the study showed that the proportion of proteolytic bacteria was found in the sediment in varying proportions in Block A and Block B with respective values, namely inlet (72%; 68%), middle (76%; 72%), and outlet (52%; 48%).Proteolytic activity index with successive values: inlet (0.4-4.0: 0.2-2.5),middle 0.6-6.0:0.4-4.0 and outlet (0.3-3.8: 0.6-4.0).Five bacterial isolates were found to have the highest proteolytic activity index (>4), namely SAT.2, SAT.7, SAT.12, SAT.11, and SET.10.This research obtained interesting results regarding the activity index and proportion of proteolytic bacteria isolated from rice fish sediments.Most of the proportions of proteolytic bacteria from both blocks showed higher proportions than the general bacteria obtained.Therefore, it can be concluded that bacterial isolates are capable of biodegrading proteins found in organic materials.