Search Results (465)

Small water bodies are widely spread and play crucial roles in supporting regional agricultural and aquaculture activities. PlanetScope imagery has a high resolution (3 m) with daily global coverage and has obviously enhanced small water body mapping. Recent studies have demonstrated the effectiveness of deep learning for mapping small water bodies using PlanetScope; however, a persistent challenge remains in the scarcity of high-quality, manually annotated water masks used for model training, which limits the generalization capability of data-driven deep learning models. In this study, we propose a transfer learning framework that leverages Sentinel-2 data to improve PlanetScope-based small water body mapping, capitalizing on the spectral interoperability between PlanetScope and Sentinel-2 bands and the abundance of open-source Sentinel-2 water masks. Eight state-of-the-art segmentation models have been explored. Additionally, this paper presents the first assessment of the VMamba model for small water body mapping, building on its demonstrated success in segmentation tasks. The models were pre-trained using Sentinel-2-derived water masks and subsequently fine-tuned with a limited set (1292 image patches, 256 × 256 pixels in each patch) of manually annotated PlanetScope labels. Experiments were conducted using 5648 image patches and two areas of 9636 km² and 2745 km², respectively. Among the evaluated methods, VMamba achieved higher accuracy compared with both CNN- and Transformer-based models. This study highlights the efficacy of combining global Sentinel-2 datasets for pre-training with localized fine-tuning, which not only enhances mapping accuracy but also reduces reliance on labor-intensive manual annotation in regional small water body mapping. Full article

In this study, we sought to improve the productivity of Far Eastern catfish (Silurus asotus) and tropical eel (Anguilla bicolor), which are high-value fish species in the Republic of Korea, as well as that of associated crops by applying biofloc technology (BFT)-based aquaponics systems. The following three systems were used: the flow-through system (FTS), BFT, and BFT aquaponics system (BAPs). Caipira lettuce (Lactuca sativa) was utilized and hydroponics (HP) was implemented to compare crop productivity. After 42 days of treatment, the BAPs and BFT systems improved fish productivity, with weight gain rates of 134.47 ± 1.80% in BAPs-cat, 130.38 ± 0.95% in BFT, and 114.21 ± 6.62% in FTS for S. asotus, and 70.61 ± 3.26% in BAPs-eel, 62.37 ± 7.04% in BFT, and 47.83 ± 1.09% in FTS for A. bicolor. During the experiment, the total ammonia nitrogen and NO₂⁻-N concentrations were stable in all plots. In the case of NO₃⁻-N, BFT showed an increasing tendency while both BAPs showed a decrease compared with that of the BFT. BAPs-cat (total weight: 224.1 ± 6.37 g) and HP (220.3 ± 7.17 g) resulted in similar growth. However, in BAPs-eel was 187.7 ± 3.46 g due to root degradation. Water content analysis showed that BAPs-cat and BAPs-eel contained sufficient K, Ca, P, and S, which are important for crop growth. Overall, the effect of BAPs on fish growth was higher than that of FTS. This study reveals that integrating BFT with aquaponics improves productivity for high-value fish and associated crops while maintaining stable water quality. This method offers sustainable, efficient production, reduces environmental impact, and provides insights for future research in sustainable aquaculture practices. Full article

In this study, the distribution patterns of the nitrifying and denitrifying microbiome in a large-scale biofilter (587.24 m³) in a cold freshwater recirculating aquaculture system (RAS) was investigated. Previous studies have revealed that the water quality, nitrification, and denitrification rates in the front (BFF), middle (BFM), and back (BFB) of this biofilter are different. The results showed the highest diversity of the denitrifying microbiome in the BFB, followed by BFF and BFM, whereas nitrifying microbiome diversity remained consistent across different positions. Two genera, Nitrosomonas and Nitrosospira, dominated the nitrifying microbiome, while Pseudomonas, Thauera, Cupriavidus, Dechloromonas, Azoarcus, and Paracoccus comprised the top six denitrifying genera. Principal coordinate analysis indicated a distinct spatial distribution pattern of the denitrifying microbiome but not the nitrifying microbiome. The genera Pseudomonas and Dechloromonas were the biomarkers of the BFF and BFB, respectively. Redundancy analysis showed that nitrite, nitrate, dissolved oxygen, and soluble reactive phosphorus influenced the functional microbiome distribution pattern. Network correlation analysis identified one nitrifying hub (Nitrosospira) in the BFF, five denitrifying hubs (Aromatoleum, Dechloromonas, Paracoccus, Ruegeria, and Thauera) in the BFM, and three denitrifying hubs (Azoarcus, Magnetospirillum, and Thauera) in the BFB. Exclusively negative correlations were found between hubs and its adjacent nodes in the BFF and BFB. This study demonstrates that habitat can shape the distribution patterns of the nitrifying and denitrifying microbiome in the biofilter of the RAS, with the BFF exhibiting greater benefits for the nitrification process. Full article

Microbial feed additives can effectively promote the healthy development of aquaculture, and Lactobacillus acidophilus can be utilized to mitigate disease risks and enhance productivity while minimizing antibiotic use. This article summarizes research on the application of L. acidophilus in aquaculture, focusing on growth and nutrient utilization, intestinal structure and microbial communities, disease prevention and control in aquatic organisms, and the regulation of water quality. This review holds significant implications for the development of compound feed additives and environmental regulators involving L. acidophilus, as well as for future aquatic food safety. Full article

Aquaculture is vital for global food security but faces challenges like disease, water quality control, and resource optimization. Digital twin technology, a real-time virtual replica of physical aquaculture systems, emerges as a transformative solution. By integrating sensors and data analytics, it enables monitoring and optimization of water quality, feed efficiency, fish health, and operations. This review explores the current adoption status of digital twins in aquaculture, highlighting applications in real-time monitoring and system optimization. It addresses key implementation challenges, including data integration and scalability, and identifies emerging opportunities for advancing sustainable, intelligent aquaculture practices. Full article

Aquaculture is a crucial food-producing sector that can supply more essential nutrients to nourish the growing human population. However, it faces challenges, including limited water quality and space competition. These constraints have led to the intensification of culture systems for more efficient resource use while maintaining or increasing production levels. However, intensification introduces stress risks to cultured organisms by, for instance, overcrowding, waste accumulation, and water quality deterioration, which can negatively affect the growth, health, and immunity of animals and cause diseases. Additionally, environmental changes due to climate and anthropogenic activities further intensify the environmental stress for aquaculture organisms, including crustaceans. Shrimp are one of the most widely cultured and consumed farmed crustacea. Relative to aquatic vertebrates such as fish, the physiology of crustaceans has simpler physiological structures, as they lack a spinal cord. Consequently, their stress response mechanisms follow a single pathway, resulting in less complex responses to stress exposure compared to those of fish. While stress is considered a primary factor influencing the growth, health, and immunity of shrimp, comprehensive research on crustacean stress responses remains limited. Understanding the stress response at the organismal and cellular levels is essential to identify sensitive and effective stress biomarkers which can inform the development of targeted intervention strategies to mitigate stress. This review provides a comprehensive overview of the physiological changes that occur in crustaceans under stress, including hormonal, metabolic, hematological, hydromineral, and phenotypic alterations. By synthesizing current knowledge, this article aims to bridge existing gaps and provide insights into the stress response mechanisms, paving the way for advancements in crustacean health management. Full article

Optimizing hydrodynamic performance and dissolved oxygen (DO) distribution is essential for improving water quality management in industrial recirculating aquaculture systems. This study combines experimental measurements and data analysis to evaluate the effects of the inlet pipe flow rate (Q), deployment distance ratio (d/r), deployment angle (θ), inlet pipe structure on hydrodynamics and the dissolved oxygen distribution across various tank layers. The flow field distribution in the tanks was measured using Acoustic Doppler Velocimetry (ADV), and the hydrodynamic characteristics, including average velocity (v_avg) and the velocity uniformity coefficient (DU₅₀), were quantitatively analyzed. The dissolved oxygen content at different tank layers was recorded using an Aquameter GPS portable multi-parameter water quality analyzer. The findings indicate that average velocity (v_avg) and the velocity uniformity coefficient (DU₅₀) are key determinants of the hydrodynamic characteristic of circular aquaculture tanks. Optimal hydrodynamic performance occurs for the vertical single-pipe porous configuration at Q = 9 L/s, d/r = 1/4, and θ = 45°,the average velocity reached 0.0669 m/s, and the uniformity coefficients attained a maximum value of 40.4282. In a vertical single-pipe porous structure, the tank exhibits higher dissolved oxygen levels compared to a horizontal single-pipe single-hole structure. Under identical water inflow rates and deployment distance ratios, dissolved oxygen levels in the surface layer of the circular aquaculture tank are significantly greater than that in the bottom layer. The results of this study provide valuable insights for optimizing the engineering design of industrial circular aquaculture tanks and addressing the dissolved oxygen distribution across different water layers. Full article

Biofloc technology (BFT), traditionally centered on feed supplementation and water purification in aquaculture, harbors untapped multifunctional potential as a sustainable resource management platform. This review systematically explores beyond conventional applications. BFT leverages microbial consortia to drive resource recovery, yielding bioactive compounds with antibacterial/antioxidant properties, microbial proteins for efficient feed production, and algae biomass for nutrient recycling and bioenergy. In environmental remediation, its porous microbial aggregates remove microplastics and heavy metals through integrated physical, chemical, and biological mechanisms, addressing critical aquatic pollution challenges. Agri-aquatic integration systems create symbiotic loops where nutrient-rich aquaculture effluents fertilize plant cultures, while plants act as natural filters to stabilize water quality, reducing freshwater dependence and enhancing resource efficiency. Emerging applications, including pigment extraction for ornamental fish and the anaerobic fermentation of biofloc waste into organic amendments, further demonstrate its alignment with circular economy principles. While technical advancements highlight its capacity to balance productivity and ecological stewardship, challenges in large-scale optimization, long-term system stability, and economic viability necessitate interdisciplinary research. By shifting focus to its underexplored functionalities, this review positions BFT as a transformative technology capable of addressing interconnected global challenges in food security, pollution mitigation, and sustainable resource use, offering a scalable framework for the future of aquaculture and beyond. Full article

Although biofloc technology (BFT) currently offers advantages such as improving aquaculture water quality, providing natural bait for cultured animals, and reducing pests and diseases, single BFT systems face technical bottlenecks, including the complex regulation of the carbon–nitrogen ratio, accumulation of suspended substances, and acidification of the bottom sludge. Therefore, constructing a composite system with complementary functions through technology integration, such as with aquaponics, biofilm technology, integrated multi-trophic aquaculture systems (IMTAs), and recirculating aquaculture systems (RASs), has become the key path to breaking through industrialization barriers. This paper systematically reviews the action mechanisms, synergistic effects, and challenges of the four mainstream integration models incorporating BFT, providing theoretical support for the environmental–economic balance of intensive aquaculture. Full article

Aquaculture expansion to meet global protein demand has intensified concerns over nutrient pollution and greenhouse gas (GHG) emissions. While floating treatment wetlands (FTWs) are proven for water quality improvement, their potential to mitigate GHG emissions in marine aquaculture remains poorly understood. This study quantitatively evaluated the dual capacity of Sesuvium portulacastrum FTWs to (a) regulate dissolved inorganic nitrogen (DIN) and (b) reduce CO₂/N₂O emissions in grouper aquaculture systems. DIN speciation (NH₄⁺, NO₂⁻, NO₃⁻) and CO₂/N₂O fluxes of six controlled ponds (three FTW and three control) were monitored for 44 days. DIN in the FTW group was approximately 90 μmol/L lower than that in the control group, and the water in the plant group was more “oxidative” than that in the control group. The former groups were dominated by NO₃⁻, with lower dissolved inorganic carbon (DIC) and N₂O concentrations, whereas the latter were dominated by NH₄⁺ during the first 20 days of the experiment and by NO₂⁻ at the end of the experiment, with higher DIC and N₂O concentrations on average. Higher primary production may be the reason that the DIC concentration was lower in the plant group than in the control group, whereas efficient nitrification and uptake by plants reduced the availability of NH₄⁺ in the plant group, thereby reducing the production of N₂O. A comparison of the CO₂ and N₂O flux potentials in the plant group and control group revealed that, in the presence of FTWs, the CO₂ and N₂O emissions decreased by 14% and 36%, respectively. This showed that S. portulacastrum FTWs effectively couple DIN removal with GHG mitigation, offering a nature-based solution for sustainable aquaculture. Their low biomass requirement enhances practical scalability. Full article

With the rapid expansion of the aquaculture scale, the environmental pollution caused by the accumulation of fish pond sediment (FPS) has become increasingly prominent, making it urgent to establish sustainable resource utilization solutions. This study investigates the potential of using FPS as a soil amendment to improve saline–alkali soil (SAS) quality and enhance vegetable growth, while also quantifying ecological benefits through Gross Ecosystem Product (GEP) accounting. A pot experiment was conducted to evaluate the effects of different FPS mass percentages (0%, 20%, 40%, 80%, and 100%) on the growth of three vegetables (water spinach, lettuce, and chili) and soil quality. The results demonstrated that FPS addition at ≥40% significantly improves SAS quality, reducing the pH and salinity (p < 0.05), while enhancing organic matter, nutrient availability, and microbial activity. Among the treatments, 80% FPS maximized vegetable yields, with water spinach achieving the highest edible biomass (37.32 g). Compared to the control, nutritional quality under ≥80% FPS treatment showed substantial increases: vitamin C (133.33–307.03%), soluble sugars (49.97–73.53%), and protein (26.14–48.08%). An economic analysis revealed that 80% FPS with water spinach cultivation generated peak ecological benefits (274,951 CNY·ha⁻¹; 185% above control). These findings provide a scientific basis and effective model for the resource utilization of FPS and the improvement of saline–alkali soil, offering significant implications for the sustainable development of agriculture and environmental protection. Full article

This study used microscopy-based quantitative enumeration to investigate the effects of large-scale Sargassum fusiforme cultivation on coastal water quality and phytoplankton communities. Data from April (cultivation period) and June (non-cultivation period) in 2018 and 2019 showed that cultivation increased pH and dissolved oxygen (DO). It also reduced nitrate–nitrogen (NO₃–N), nitrite–nitrogen (NO₂–N), phosphate–phosphorus (PO₄–P), total phosphorus (TP), and silicate–silicon (SiO₃–Si) concentrations. These changes indicate improved coastal water quality from S. fusiforme cultivation. Nutrient levels rose again during the non-cultivation period. This suggests that water purification decreased without cultivation. Cultivation also lowered the dominance of Skeletonema costatum. This led to a more diverse and stable phytoplankton community. Microscopic observation is valuable for quantifying larger phytoplankton species, and plays an important role in ecological monitoring. These findings provide insights for sustainable aquaculture and ecological restoration. Full article

The rising demand for sustainable aquaculture necessitates innovative solutions to environmental and operational challenges. Biofloc technology (BFT) has emerged as an effective method, leveraging microbial communities to enhance water quality, reduce feed costs, and improve fish health. However, traditional BFT systems are susceptible to water quality fluctuations, demanding precise monitoring and control. This review explores the integration of Artificial Intelligence (AI) and Internet of Things (IoT) technologies in smart BFT systems, highlighting their capacity to automate processes, optimize resource utilization, and boost system performance. IoT devices facilitate real-time monitoring, while AI-driven analytics provide actionable insights for predictive management. We present a comparative analysis of AI models, such as LSTM, Random Forest, and SVM, for various aquaculture prediction tasks, emphasizing the importance of performance metrics like RMSE and MAE. Furthermore, we discuss the environmental and economic impacts, including quantitative case studies on cost reduction and productivity increases. This paper also addresses critical aspects of AI model reliability, interpretability (SHAP/LIME), uncertainty quantification, and failure mode analysis, advocating for robust testing protocols and human-in-the-loop systems. By addressing these challenges and exploring future opportunities, this article underscores the transformative potential of AI and IoT in advancing BFT for sustainable aquaculture practices, offering a pathway to more resilient and efficient food production. Full article

Pollutants and pathogens in aquaculture systems may cause economic losses and threaten public health. Yet, the risks associated with microbiological contaminants and their relationship with environmental factors remain largely unknown. In this study, two typical eel farms in southeast China were chosen for investigation of water quality and microbial community in the treatment processes. It was found that flocculant addition can only effectively reduce total phosphorus (TP) in both farms. However, excessive total nitrogen (TN) was found (6.16 mg/L and 6.74 mg/L, respectively). NH₄⁺ (3.98 mg/L) was the main nitrogen pollutant in QR farm, while NO₃⁻ (3.81 mg/L) and NO₂⁻ (1.22 mg/L) were the main nitrogen pollutants in ZJ farm. The treatment processes could not effectively remove nitrogen pollution, and the abundance of nitrogen functional bacteria was low. NO₂⁻ was positively correlated with Verrucomicrobiota (p < 0.05). NH₄⁺ and TN were significantly negatively correlated with Nitrospirota and unclassified_f_Anaerolineaceae, respectively (p < 0.05). Some typical pathogens associated with aquaculture (e.g., Lactococcus) and human beings (e.g., Escherichia-Shigella,) were found in the systems. This study proposes suggestions for aquaculture tailwater by analyzing the shortcomings of the existing treatment processes. Meanwhile, it offers certain support for the prevention of pathogen risks in aquaculture systems. Full article

The latest FAO report indicates that aquaculture accounts for 51% of the global production volume of fish and seafood. However, despite the continuous growth of this activity, there is evidence of the excessive use of groundwater in its production processes, as well as pollution caused by nutrient discharges into surface waters due to the water exchange required to maintain water quality in fishponds. Given this context, the objectives of this study were as follows: (1) to review which emergent and floating plant species are used in constructed wetlands (CWs) for the bioremediation of aquaculture wastewater; (2) to identify the aquaculture species whose wastewater has been treated with CW systems; and (3) to examine the integration of CWs with recirculating aquaculture systems (RASs) for water reuse. A systematic literature review was conducted, selecting 70 scientific articles published between 2003 and 2023. The results show that the most used plant species in CW systems were Phragmites australis, Typha latifolia, Canna indica, Eichhornia crassipes, and Arundo donax, out of a total of 43 identified species. These plants treated wastewater generated by 25 aquaculture species, including Oreochromis niloticus, Litopenaeus vannamei, Ictalurus punctatus, Clarias gariepinus, Tachysurus fulvidraco, and Cyprinus carpio, However, only 40% of the reviewed studies addressed aspects related to the incorporation of RAS elements in their designs. In conclusion, the use of plants for wastewater treatment in CW systems is feasible; however, its application remains largely at the experimental scale. Evidence indicates that there are limited real-scale applications and few studies focused on the reuse of treated water for agricultural purposes. This highlights the need for future research aimed at production systems that integrate circular economy principles in this sector, through RAS–CW systems. Additionally, there is a wide variety of plant species that remain unexplored for these purposes. Full article