Search Results (100)

This field study examined extant aquatic food production and marketing in the three coastal states of Lagos, Ogun, and Ondo before IMTA across 15 Local Government Areas (LGAs)/Local Council Development Areas (LCDAs). Marketing mix practices in coastal aquatic food systems were explored through a structured, qualitative assessment using a multi-value chain perspective. Monthly sales volumes most frequently fell within the range of 1–5 tonnes. The local market was dominant, with some sales in the international markets. Respondents asserted that post-harvest processing was diverse, and some were satisfied with the technology available to preserve their products. Cold storage practices across coastal states were hindered by unreliable power supply. Zero-level channel distribution dominated among traders, with over 90% relying on word-of-mouth (WOM) to promote their products. Consumers showed a strong preference for the quality of local products and expressed openness to incorporating seaweed into their purchases. Health benefits, taste, and other reasons for purchase decisions varied significantly across the state χ² (df = 8, n = 300) = 92.39, p < 0.001. These findings provide a baseline for IMTA in Nigeria, highlighting existing strengths, market dynamics, and infrastructure gaps that must be addressed to support sustainable integration. Full article

The integration of multiple species has been proposed as a strategy to improve resource use efficiency in intensive aquaculture systems. This study evaluated the inclusion of a native fish species, yellowtail lambari (Astyanax bimaculatus), in a biofloc-based aquaponic system co-cultivating Nile tilapia (Oreochromis niloticus) and lettuce (Lactuca sativa var. capitata). The experiment was conducted over 35 days using eight experimental units with two treatments (with and without lambari) and four replicates. Water quality, zootechnical performance, lettuce growth, hematological parameters of tilapia, and nitrogen and phosphorus retention were assessed. The presence of lambari was associated with lower total ammonia nitrogen, toxic ammonia, and total suspended solids, particularly during the final stage of the experimental period (p < 0.05), as well as reduced pH and alkalinity, likely reflecting increased microbial activity. Lettuce cultivated in the lambari treatment showed higher final weight, leaf height, and total biomass (p < 0.05), resulting in increased system productivity. No significant differences were observed in growth performance or hematological parameters of Nile tilapia (p > 0.05). In addition, nitrogen and phosphorus retention at the system level were higher in the lambari treatment (p < 0.05), although no differences were detected when fish and plants were evaluated separately. These results indicate that the inclusion of a native fish species can influence nutrient retention and productivity in biofloc-based aquaponic systems without compromising the performance of the primary cultured species. Full article

Eutrophication driven by excess nitrogen (N) and phosphorus (P) remains a pervasive global water-quality challenge, necessitating scalable nutrient recovery strategies that extend beyond conventional treatment approaches. This review synthesizes the emerging literature on algae-based systems as dual-purpose platforms for nutrient mitigation and biomass valorization. We examine systems including seaweed bioextraction, integrated multi-trophic aquaculture, algal turf scrubbers, and wastewater phycoremediation, while highlighting reported nutrient removal efficiencies and operational constraints. Beyond remediation, the spectrum of valorization pathways considered ranges from biofertilizers, feed, bioenergy, and materials to nutraceuticals, cosmetics, biomedical materials, biomanufacturing, and methane-mitigating livestock additives. The review emphasizes the economic and logistical challenges linking remediation-scale biomass production to commercial markets, including the contamination risk, processing intensity, regulatory classification, and scale mismatch. We propose an integrated remediation–valorization framework to guide research, policy, and industry toward nutrient-circular, economically viable restoration strategies. Full article

Understanding the feeding physiological mechanisms of determined oyster species is fundamental for adaptation and growth stabilization, aiming for gains in aquaculture production. To assess its potential for Integrated Multi-Trophic Aquaculture (IMTA) with shrimp, we analyzed the feeding physiology of the mangrove oyster Crassostrea gasar. In this study, we determined the feeding physiology of the mangrove oyster Crassostrea gasar, a commercially important species in tropical Brazil, under two diets, live microalgae (ISO—Isochrysis galbana) and biofloc (BFT), which were tested at four concentrations (10, 20, 30, and 40 mg L⁻¹), to establish whether this species can effectively utilize BFT as a food source. Results indicated that ISO diet promoted superior filtration, characterized by a higher proportion of feces (F), suggesting a reduced need for intensive particle selection. Both clearance (CR) and filtration (FR) rates peaked at 30 mg L⁻¹ before declining, suggesting a physiological threshold for this diet. In contrast, the BFT diet elicited higher CR and FR values but triggered excessive pseudofeces (PF) production and low net organic selection efficiency (NOSE). This suggests high particle rejection and limited nutritional assimilation. In conclusion, while C. gasar can process BFT, it is metabolically disadvantageous as a sole food source. For an optimal performance, I. galbana concentrations should be maintained at or below 30 mg L⁻¹. Full article

Controlled-environment agriculture (CEA) and circular production systems require coordinated monitoring of biological and physicochemical processes across trophic levels. This project report presents the implementation of a multi-trophic controlled-environment agriculture demonstrator that integrates computer-vision-based monitoring with established sensor infrastructure for aquaculture, poultry, plants, microalgae, duckweed, and insect modules. Stereo imaging and RGB-D systems are deployed for non-invasive quantification of fish biomass and plant growth, while continuous water-quality and environmental measurements (e.g., pH, dissolved oxygen, nitrate, ammonium, temperature, CO₂) provide complementary process data. These data streams are synchronized within a shared database architecture to enable cross-module evaluation of nutrient dynamics, growth progression, and operational stability under real facility conditions. The implemented framework demonstrates how computer vision can extend conventional sensor-based monitoring by directly capturing biological performance indicators across aquatic, terrestrial, and microbial domains. While advanced predictive modeling and full digital twin simulation remain future development steps, the realized data-integration architecture establishes a structural foundation for the systematic evaluation of circular indoor food-production systems. The demonstrator illustrates how multimodal monitoring can support nutrient recirculation, transparency of biological variability, and data-driven assessment within controlled multi-trophic environments. Full article

Integrated multitrophic aquaculture (IMTA) emerges as a sustainable strategy to control the excess of solids and inorganic nutrients that tend to increase in the biofloc system (BFT) cycle, since the model integrates organisms from different trophic levels sharing the same system and nutrients. Thus, this study compared a Penaeus vannamei monoculture system with an integrated biofloc system including Mugil liza, Holothuria grisea, Crassostrea tulipa, and Salicornia neei, focusing on water quality and the performance of organisms and systems. This study consisted of three monoculture systems (16 m³; 375 shrimp m⁻³) and three IMTA systems, composed of a shrimp tank (16 m³), a mullet tank (4 m³; 30 ind m⁻³), a combined tank (3 m³) for oysters (45 ind m⁻³) and sea cucumbers (3 ind m⁻²), and a Salicornia neei bed (2.78 m²; 37 ind m⁻²). All IMTA systems operated in recirculation without water exchange, using 10% of the established biofloc inoculum. The IMTA system had half the hydrated lime use (2.13 vs. 4.29 kg), lower solids (299.56 vs. 373.33 mg L⁻¹), and reduced sludge production (9.37 vs. 15.87 kg). Shrimp growth was similar in both systems. Mullet grew adequately with a survival rate of 95.8%, but oysters showed a survival rate of 45.7%. Sea cucumber had a survival rate of 100% until day 28, when a marked decline appeared, strongly correlated with rising temperature (>28 °C; r = −0.71). This resulted in a significant increase in solids in the last weeks, suggesting that the population decline reduces solids control capacity. Furthermore, the biofloc in IMTA was dominated by coccoid forms, with lower proportions of filamentous and cyanobacterial forms. Full article

Developing the bioeconomy offers a critical sustainable path away from fossil fuels by using renewable biological resources to create feed, food, materials, and energy; fostering decarbonization; and supporting circular economic growth. However, the pivotal role of different demonstration facilities in unlocking viable bio-based products remains to be fully defined and appreciated. This review addresses the importance and added value of developing a novel integrated multi-trophic aquaculture (IMTA) demonstration site in the peatlands as a scalable facility to support companies and end-users who are co-creating and testing appropriate bio-based products for new markets along with de-risking for investments. The operational activities necessary to develop and launch a fully functional IMTA-based bioeconomy demonstration site to meet a diversity of end-user expectations are considerable, including many unforeseen challenges that are addressed in this review. The IMTA site offers considerable potential for building a networked ecosystem of end-users (farmers, start-ups, entrepreneurs, companies, policy-makers), enabling alternative uses of land along with tailoring strategic policies for enhancing regional resilience and competitiveness with a global orientation. Full article

This review examines the status, challenges, and future trajectories of global mussel aquaculture within the blue food system. Despite steady production growth, mussels’ relative contribution to total bivalve output has significantly declined over recent decades due to disproportionate expansion of oyster, clam, and scallop sectors. A major geographical production shift has occurred, with Asia, spearheaded by China, emerging as the dominant region, supplanting traditional European producers while the Americas rapidly ascend. China’s overwhelming dominance in overall bivalve production starkly contrasts with its underdeveloped mussel sector, where growth lags behind other bivalves despite substantial absolute increases, reflecting a fundamental restructuring of species composition. The industry faces interconnected sustainability constraints: persistent vulnerabilities in spat supply stemming from environmental variability, hatchery limitations, and disease transmission risks; escalating environmental stressors including climate change impacts, harmful algal blooms, pollution, and pathogens; structural flaws in value chains characterized by fragmented production, market volatility, and underutilized byproducts; and governance challenges related to spatial access and licensing inefficiencies. This review advocates for a comprehensive strategy to boost the mussel aquaculture. These encompass advancing hatchery technology and genetic breeding programs, implementing ecosystem-based management such as multi-trophic systems and AI-enhanced environmental monitoring, restructuring value chains through producer cooperation and high value product diversification, and establishing science-based spatial planning frameworks with streamlined governance. Addressing these challenges holistically is critical to position mussel farming as a resilient pillar of sustainable blue food production capable of reconciling ecological integrity with economic viability and social equity. Full article

Integrated multi-trophic aquaculture (IMTA) has emerged as an ecological intensification strategy capable of enhancing nutrient utilization and improving environmental stability in mariculture systems, yet the microbial mechanisms driving nutrient transformations remain insufficiently understood. This study investigated how culture mode (IMTA vs. monoculture) shape water quality, sediment microbial communities, and nutrient cycling processes in a shrimp–sea urchin system by combining water-quality monitoring, nutrient analysis, 16S rRNA high-throughput sequencing, and redundancy analysis. IMTA significantly increased turbidity, chlorophyll-a, phosphate, ammonium, and nitrite compared with monoculture, while physico-chemical parameters remained stable. Sediment microbiota in IMTA exhibited substantially higher alpha diversity and showed a clear compositional separation from monoculture communities. At the genus level, IMTA sediments were enriched in Vibrio, Motilimonas, and Ruegeria, distinguishing them from monoculture systems. At the phylum level, IMTA was characterized by increased abundances of Proteobacteria and Bacteroidota, accompanied by a marked decline in Spirochaetota. Functional predictions indicated that microbial communities were predominantly characterized by pathways related to amino acid and carbohydrate metabolism, as well as nutrient remineralization. RDA and correlation analyses further identified turbidity, chlorophyll-a, phosphate, ammonium, and nitrite as the principal drivers of microbial divergence. Overall, the findings demonstrate that IMTA reshapes sediment microbial communities toward more efficient nutrient-processing assemblages, thereby promoting active nitrogen and phosphorus transformations and improving biogeochemical functioning relative to monoculture. These results provide mechanistic insight into how IMTA supports nutrient recycling and environmental sustainability in modern mariculture systems. Full article

The convergence of food insecurity, water scarcity, and environmental degradation has intensified the global search for sustainable agricultural models. Integrated Microalgal–Aquaponic Systems (IAMS) have emerged as a novel multi-trophic platform that unites aquaculture, hydroponics, and microalgal cultivation into a closed-loop framework for resource-efficient food production and water recovery. This critical review synthesizes empirical findings and engineering advancements published between 2008 and 2024, evaluating IAMS performance relative to traditional agriculture and recirculating aquaculture systems (RAS). Reported under controlled laboratory and pilot-scale conditions, IAMS have achieved nitrogen and phosphorus recovery efficiencies exceeding 95% while potentially reducing water consumption by up to 90% compared to conventional farming. The integration of microalgal photobioreactors enhances nutrient retention, may contribute to internal carbon capture, and enables the generation of diversified co-products, including biofertilizers and protein-rich aquafeeds. Nevertheless, significant barriers to commercial scalability persist, including the biological complexity of maintaining multi-trophic synchrony, high initial capital expenditure (CAPEX), and regulatory ambiguity regarding the safety of waste-derived algal biomass. Technical challenges such as photobioreactor upscaling, biofouling control, and energy optimization are critically discussed. Finally, the review evaluates the alignment of IAMS with UN Sustainable Development Goals 2, 6, and 13, and outlines future research priorities in techno-economic modeling, automation, and policy development to facilitate the transition of IAMS from pilot-scale innovations to viable industrial solutions. Full article

Small pelagic fish, including sardines, are essential to global fisheries and aquaculture feed production. However, these species are increasingly exposed to intense exploitation. In Chile, the common sardine (Strangomera bentincki), endemic to the Humboldt Current System, supports major industrial and artisanal fisheries. Landings are expected to reach 300,000 tons by 2025, mostly for fishmeal production. As a keystone species, S. bentincki is highly sensitive to environmental variability during early development, which can reduce recruitment and threaten long-term population sustainability. This interdisciplinary approach integrates ecological and biotechnological perspectives to assess the feasibility of controlled juvenile sardine production in land-based Ecological Aquaculture (EA) systems, including Recirculating Aquaculture Systems (RAS) and Integrated Multi-Trophic Aquaculture (IMTA), which are designed to reduce environmental impacts. These systems enable precise control of temperature, feeding regimes, and water quality, facilitating investigations into larval and juvenile survival, growth performance, and physiological responses under variable thermal and nutritional conditions. Emphasis is placed on fatty acid metabolism during ontogeny, particularly docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), which are essential for somatic growth, reproductive development, and thermal tolerance. Developing standardized protocols for juvenile S. bentincki culture addresses key gaps in husbandry and physiology (temperature threshold, nutrient density, larval growth rate, etc.) while introducing a novel ecological–aquaculture integration framework. This approach links early-life ecology with applied rearing techniques to support stock enhancement, strengthen artisanal fisheries, and promote sustainable aquaculture diversification under increasing environmental variability. Full article

Marine sponges are recognized as reservoirs of diverse microorganisms that produce bioactive natural compounds. In this study, we conducted a metataxonomic analysis of Geodia cydonium specimens collected from four sites in Italy: Secca delle Fumose (Gulf of Naples, Tyrrhenian Sea), Mar Piccolo of Taranto and an Integrated Multi-Trophic Aquaculture (IMTA) system in Mar Grande of Taranto (both located in the Ionian Sea), and Polignano a Mare (Adriatic Sea). Our results revealed a highly diverse microbial community within the sponges, encompassing 24 bacterial phyla. Among these, Chloroflexota was the most abundant phylum, accounting for an average of 30.2% of the total community across all samples. In addition, the majority of the microbiota was composed of Actinomycetota, Proteobacteria, Acidobacteriota, Poribacteriota, Gemmatimonadota, and Dadabacteria. The sponge sample from Polignano a Mare exhibited the richest and most diverse bacterial community. This observation was supported by phylogenetic analysis, which identified seven bacterial genera, Albidovulum, Filomicrobium, Microtrix, Gaiellales, D90 (Gammaproteobacteria class), and Blastopirellula, exclusive to this site. Several of these taxa are known for their potential biotechnological applications, underlining the significance of site-specific microbial diversity in G. cydonium. Full article

This review analyzes current research on short-term culture of sea urchin from barrens through formulated feed, addressing the need for sustainable aquaculture practices and ecological restoration of kelp forests. We compare the results of multiple studies to identify the optimal feed composition to induce gonad growth and coloration. Our analysis suggests that macroalgae are the best feed ingredients to improve gonad growth and coloration; however, environmental and economic challenges persist in expanding sea urchin production with these types of ingredients. Plant-based protein sources like soy have emerged as a potential cost-effective alternative to fish products; nevertheless, the presence of antinutritional factors in soy products limits their inclusion in formulated feed. Regarding the composition and amount of lipids, we found that they are critical macronutrients in gonad development. The review also explores the potential of sea urchin aquaculture in mitigating urchin barrens and restoring kelp forests, highlighting the interplay between ecological and economic factors. We identify key knowledge gaps and propose future research directions, including large-scale economic viability assessments, novel feed additives, and integrated multitrophic aquaculture systems. These findings have significant implications for developing sustainable and economically viable sea urchin aquaculture, potentially transforming urchin barrens into productive ecosystems while meeting market demand for roe. Full article

The red macroalga Porphyra plays a key role in Integrated Multi-Trophic Aquaculture (IMTA) systems, acting both as a biofilter and as a source of bioactive compounds (BACs) with nutritional and photoprotective value. This study evaluated how nitrogen source and concentration influence its physiological, photosynthetic, and biochemical responses under ultraviolet radiation (UVR). Gametophytes were cultured for four days under two nitrate sources (artificial and fishpond effluents) at 3 and 5 mM concentrations and exposed to PAR (120 µmol·photons·m⁻²·s⁻¹) and UVR (9 W·m⁻² for 6 h·day⁻¹). Morphological responses, photosynthetic performance, and BACs were quantified. Nitrate uptake increased with nitrate concentration, while growth rate remained unaffected. Samples grown with fishpond effluents, particularly at 3 mM, showed darker pigmentation and higher phycoerythrin and mycosporine-like amino acid (MAA) contents, indicating enhanced nitrogen assimilation and photoprotective capacity. Conversely, 3 mM artificial nitrate in the water promoted the highest electron transport rate and lowest non-photochemical quenching, suggesting greater photosynthetic capacity. Polyphenols and antioxidant activity showed no significant differences among treatments, indicating similar stress status. Overall, it is suggested that fishpond effluents acted as a natural biostimulant, enhancing biliprotein and MAA synthesis without compromising physiological stability, reinforcing its potential for sustainable IMTA-based production of high-value photoprotective compounds. Full article

Harvesting sea urchins from barrens and enhancing their gonads through aquaculture offers a promising way to convert low-value individuals into high-quality seafood. This study evaluated whether red sea urchins (Mesocentrotus franciscanus, RSUs) fed nutrient-enriched seaweeds produced in a land-based integrated multi-trophic aquaculture (IMTA) system could significantly improve gonad size and quality. Two seaweed species, Ulva australis and Devaleraea mollis, were grown in effluent from white seabass (Atractoscion nobilis) tanks and used to feed RSUs over an 8-week period. RSUs readily consumed both seaweeds, with measurable ingestion, fecal output, and absorption efficiency. We hypothesized that RSUs fed IMTA seaweed would exhibit increased gonadosomatic index and improved gonad quality. GSI significantly increased in both groups, from an initial 3.00 ± 0.50% (9.02 ± 1.80 g) to 4.64 ± 0.66% (23.04 ± 10.20 g) in the U. australis group and to 6.35 ± 1.30% (31.20 ± 7.20 g) in the D. mollis group. Gonad quality improved from “D” (unmarketable) to average “B” (high-quality) grade, based on color, firmness, and texture. These results demonstrate that RSUs collected from barrens can be enhanced into premium seafood using nutrient-enriched seaweeds. Integrating RSUs into land-based IMTA systems may increase aquaculture efficiency, reduce waste, and diversify seafood production in a sustainable and economically viable way. Full article