Multi-trophic Aquaculture System Research Articles

Analysis of the efficiency of Gracilaria domingensis for an integrated multitrophic aquaculture system with Penaeus vannamei

A trial was conducted for 42 days to evaluate the zootechnical performance, water quality and phytoplankton community in an integrated multitrophic system of Penaeus vannamei with Gracilaria domingensis, using two commercial feeds. Three different densities (2.5; 5.0 and 7.5 kg m-3) with two percentages of crude protein (32% and 40%) were tested. The postlarvae were cultured for 42 days in a multitrophic biofloc system in a factorial experimental design (2x4). No significant difference for the water quality variables. For the zootechnical performance, the isolated influence of the density of G. domingensis was not observed, only the effect of the protein on the average final weight, specific growth rate, feed conversion ratio and yield, with better results in treatments with 40% crude protein. The integration with seaweed only influenced the total yield of the system, where these treatments presented higher values (from 3.68 to 8.67 kg m-3). In the phytoplankton community nine genera were identified, with Aphanocapsa being the dominant, without any significant difference among the combinations. Based on the results obtained in this study, it was found that the seaweed G. domingensis can be cultivated in a multitrophic system, without harming the water quality and the zootechnical performance.

Response of Hard-Bottom Macro-Zoobenthos to the Transition of a Mediterranean Mariculture Fish Plant (Mar Grande of Taranto, Ionian Sea) into an Integrated Multi-Trophic Aquaculture (IMTA) System

: This study investigates the effects on hard-bottom macro-zoobenthic communities of converting a mariculture plant into an Integrated Multi-Trophic Aquaculture (IMTA) system. This study was conducted from 2018 to 2021 in the semi-enclosed Mar Grande basin of Taranto (northern Ionian Sea), on a facility located 600 m off the coastline, with a production capacity of 100 tons per year of seabass (Dicentrarchus labrax) and seabream (Sparus aurata). The results from seasonal sampling performed in a treatment site, where bioremediators (filter-feeding invertebrates such as sponges, polychaetes, mussels, and macroalgae) were deployed, and a control site without bioremediators were compared. Before the IMTA installation, the hard substrates under the cages were sparsely inhabited, with significant sediment coverage. By 2021, the treatment site exhibited revitalized and more diverse macro-zoobenthic communities, with species richness increasing from 83 taxa in 2018 to 104 taxa, including notable growth in sponges, annelids, mollusks, and bryozoans. In contrast, the control site showed no substantial changes in biodiversity over the same period. Biodiversity indices, including Shannon and Margalef indices, improved significantly at the treatment site, particularly during summer months, highlighting a more resilient and balanced benthic environment. Taxonomic distinctness (delta+) and multivariate analyses (PERMANOVA, PCO) confirmed significant spatial and temporal shifts in community structure at the treatment site, driven by IMTA implementation. SIMPER analysis identified key taxa contributing to these changes, which played a pivotal role in structuring the community. The emergence of filter feeders, predators, and omnivores at the treatment site suggests enhanced nutrient cycling and trophic complexity, while the decline in opportunistic species further supports improved environmental conditions. These findings demonstrate the potential of IMTA to promote recovery and sustainable mariculture practices, also offering a comprehensive understanding of its positive effects on hard-bottom benthic community dynamics.

Physiological impact of ammonia-induced stress in freshwater pearl mussel, Lamellidens marginalis (Lamarck, 1819)

ABSTRACT The freshwater pearl mussel, Lamellidens marginalis is a promising candidate species for pearl farming in India and Southeast Asia. In India, this species is being intensively cultured in ponds, tanks, cisterns and freshwater integrated multi-trophic aquaculture systems, where the chance of accumulating ammonia is very high. However, no information is currently available on the effects of ammonia on the physiology of this mussel. Here, we conducted a study of the responses of Lamellidens marginalis to ammonia exposure. The 96 h LC50 of un-ionised ammonia was 4.28 mg L−1. Mussels were challenged by exposure to un-ionised ammonia at half the 96 h LC50 for 96 h. Exposure induced significant alterations in the serum biochemical profile (P < 0.05) of mussels, encompassing changes in total protein levels, alkaline phosphatase, aspartate aminotransferase and alanine aminotransferase. The activities of antioxidative enzymes, including superoxide dismutase, catalase and glutathione peroxidase, and the biomarker malondialdehyde, were significantly impacted (P < 0.05) by ammonia challenge. The antioxidant defence system may be able to protect mussels from oxidative stress during early exposure to ammonia. However, prolonged exposure to ammonia impaired antioxidant activities, emphasising the importance of maintaining water quality for a healthy environment for sustainable freshwater pearl mussel farming.

Variability in prokaryotic and eukaryotic periphyton communities in marine recirculating integrated multi-trophic aquaculture systems

Variability in prokaryotic and eukaryotic periphyton communities in marine recirculating integrated multi-trophic aquaculture systems

Identification of Aquatic Plant Species Suitable for Growing in Integrated Multi-Trophic Aquaculture Systems in Southwest Bangladesh

Giant freshwater prawn (Macrobrachium rosenbergii) farming in Bangladesh began in the 1970s and has become a significant export industry. Despite its potential, there are concerns about the environmental sustainability of prawn farming due to its high greenhouse gas (GHG) footprint, but implementation of integrated multi-trophic aquaculture (IMTA) may help minimize the GHG emission. A key element in IMTA is using plants to take up inorganic nutrients released by the prawns, producing valuable plant products and cleaning the water. Using a quadrat sampling method, we conducted a field study in combined prawn and shrimp ponds, aquaculture fishponds, and non-aquaculture waters in south- west Bangladesh to characterize plant diversity and identify suitable species for IMTA in prawn farms. A total of 38 plant species were identified with densities ranging from 4.5–6.1 plants/m2 in the aquaculture ponds to 11.6–17.1 plants/m2 in the prawn/shrimp and the non-aquaculture ponds. Free-floating plants were the most abundant, followed by emergent, floating anchored, and submerged plants. Most plants have commercial values as food, fodder, fish feed, fertilizer, or medicines to local people. Our results suggest that species within the Oxalis, Ipomoea, Azolla, and Lemna genera are suitable extractive aquatic plants for the implementation of IMTA in prawn farms and may improve the sustainability of prawn production.

Stable Isotopes Analysis of Bioremediating Organisms in an Innovative Integrated Multi-Trophic Aquaculture System

Stable Isotopes Analysis of Bioremediating Organisms in an Innovative Integrated Multi-Trophic Aquaculture System

Unlocking synergies: Enhancing bioremediation, growth, and physiological responses of Penaeus vannamei co-cultured with seaweed

Seaweeds, an inorganic extractive species in the Integrated multi-trophic aquaculture (IMTA) system, offer the potential for mitigating coastal pollution and a source of nutrition aligning with Sustainable Development Goals. A co-culture strategy was hypothesized to address rising concerns over intensive shrimp farming, limited suitable seaweed cultivation areas, and production optimization. Initially, locally available seaweeds along the Maharashtra coast were screened, followed by co-culture with P. vannamei with selected seaweed to evaluate production performance and physiological responses in zero-water exchange system. The first four-week study was conducted in shrimp wastewater with six different seaweeds, where Gracilaria foliifera performed best with significant (p < 0.05) improvement in nutrient uptake efficiency (Total ammoniacal nitrogen- 64 %, Phosphate- 99.87 %, Nitrite-32 %, Nitrate-13 %) and yield (4.56 kg m−3), enhanced elemental profile, biochemical composition, and pigments. A further optimization study of G. foliifera in shrimp wastewater for 96 h identified the optimal stocking density of 1–3.5 gL−1, based on nutrient uptake efficiency (TAN- 61 %, PO4–72 %, NO2–48 %, NO3–27 %). In the second experiment, considering the highest uptake, G. foliifera stocking density was maintained at 3.5 gL−1, and different stocking densities of P. vannamei (20, 40, 60, 80, 100 nos. m−2) were assessed with two controls, shrimp monoculture and Gracilaria monoculture. Results showed that co-culturing P. vannamei at 20 nos.m−2 followed by 60 nos.m−2 with G. foliifera at 3.5 gL−1 yielded the highest mean weight gain, specific growth rate, and production with low feed conversion ratio, while also improving water quality. The co-culture system also led to lower stress enzyme levels, reduced serum glucose and cholesterol, and normal histological observations in the hepatopancreas compared to monoculture. This study suggests that the co-culture of P. vannamei at 60 nos.m−2 with G. foliifera at 1–3.5 gL−1 proved superior without compromising productivity and physiological responses over monoculture in a sustainable manner.

Advancing Seaweed Cultivation: Integrating Physics Constraint in Machine Learning for Enhanced Biomass Forecasting in IMTA Systems

Monitoring seaweed growth rates and biomass is crucial for optimizing harvest strategies in aquaculture systems. While such a task can be managed manually on a small farm with a few seaweed tanks, it is not feasible on a commercial farm with 1000s of tanks. To this end, an Internet of Things (IoT) based seaweed growth monitoring system is being developed at Harbor Branch Oceanographic Institute (HBOI) at Florida Atlantic University (FAU). Using the Integrated Multi-Trophic Aquaculture (IMTA) system at HBOI as the test site, the project aims to develop a solution that allows farm managers to monitor seaweed growth remotely using automated sensors. An important component of this IoT solution is the machine learning-based prediction model. This study introduces an advanced Long Short-Term Memory (LSTM)-based approach for forecasting seaweed growth and biomass. In particular, an algae growth mathematical model driven by readily available environmental and aquaculture conditions has been integrated as a physical constraint in the LSTM model. This design addresses a principal challenge in this study—the lack of continuous ground truth measurements, as the biomass is recorded only at discrete intervals (e.g., initial, weekly partial harvests, and final harvest). The LSTM models are trained and evaluated for their predictive performance using experimental and synthetic data. Compared with the LSTM models with MSE loss function alone, the results showed that the model with a loss function under physics constraint achieved a significantly lower error in predicting seaweed growth. The rationale behind choosing LSTM over other state-of-the-art models is presented in the paper. This study highlights the potential of integrating machine learning with physical models to optimize seaweed cultivation and support sustainable aquaculture practices. The proposed methodology can seamlessly extend to the remote sensing data in other aquaculture settings.

Sustainable land-based IMTA: Holistic management of finfish, mussel, and macroalgae interactions, emphasizing water quality and nutrient dynamics

This research aims to minimize the environmental impact and promote the sustainability of aquaculture by optimizing nutrient dynamics, improving water quality and enhancing species growth performance through a land-based Integrated Multi-Trophic Aquaculture (IMTA) system. The study focused on Black Sea trout (Salmo labrax), Mediterranean mussel (Mytilus galloprovincialis), and sea lettuce (Ulva lactuca), reared in interconnected tanks using Black Sea water over 90 days. The Black Sea trout more than doubled in size to 333.92 ± 6.60 g and significant improvements were observed in the specific growth rate (SGR) at 0.85% and the feed conversion ratio (FCR) at 1.38. The fish's proximate composition included 19.19% protein, 2.31% lipid, 70.35% moisture, and 1.34% ash, with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) levels at 6.06% and 13.50%, respectively. The macroalgae showed substantial growth, with a SGR of 0.34% and a weight gain of 310 ± 3.50 g. Additionally, it increased protein content by 13.41% and demonstrated significant nutrient removal efficiencies: 41.4% for nitrate, 66.7% for nitrite, and 90.8% for ammonia. EPA and DHA levels increased by 45% and 70%, reaching 4.66% and 2.19%, respectively. In contrast, the mussels experienced a weight loss, with a weight gain of −1.20 ± 0.00 g and an SGR of −0.20%. Initially, wild mussels had a composition of 77.56% moisture, 13.79% protein, 1.54% lipid, and 1.77% ash. The presence of mussels and macroalgae significantly improved water quality, notably reducing ammonia by 92.2%, nitrate by 44.6% and nitrite by 75%, benefiting the overall ecosystem. This study concludes that a land-based IMTA system enhances sustainable aquaculture by improving product quality and bioremediation, with macroalgae playing a crucial role in nutrient absorption and growth within the system.

Economic viability of seaweed and sea cucumber culture using integrated multitrophic aquaculture systems in Zanzibar, Tanzania

Economic viability of seaweed and sea cucumber culture using integrated multitrophic aquaculture systems in Zanzibar, Tanzania

Growth, Productivity and Nutrient Uptake Rates of Ulva lactuca and Devaleraea mollis Co-Cultured with Atractoscion nobilis in a Land-Based Seawater Flow-Through Cascade IMTA System

To advance environmentally friendly technologies in the aquaculture of Atractoscion nobilis, and simultaneously to diversify seafood production, a 79-day trial was conducted to assess the performance of Ulva lactuca and Devaleraea mollis cultured in the effluent from A. nobilis in a land-based integrated multi-trophic aquaculture (IMTA) system in southern California, USA. Water quality and performance of macroalgae were measured weekly. The impacted factors on the growth of macroalgae and nutrient uptake rate of macroalgae were assessed. The specific growth rate of juvenile A. nobilis was 0.47–0.52%/d. Total ammonia nitrogen in effluents of A. nobilis tanks ranged from 0.03 to 0.19 mg/L. Ulva lactuca and D. mollis achieved an average productivity of 24.53 and 14.40 g dry weight (DW)/m2/d. The average nitrogen content was 3.48 and 4.89% DW, and accordingly, the average nitrogen uptake rate was 0.88 and 0.71 g/m2/d, respectively. Temperature and nutrient concentration were key factors impacting macroalgae growth, and light intensity also impacted the growth of D. mollis. The high protein content of U. lactuca and D. mollis would make them good for use as human or animal food, or for use in other industries. Research on the interaction effects between seawater exchange rates and aeration rates on the performance and nutrient uptake rates of macroalgae will be conducted in future studies.

Influence of an innovative IMTA system (Mediterranean Sea, Italy) on environmental and biological parameters: Seasonal analysis

The influence of benthic suspension feeders as bioremediating organisms on water column seston and their ability to mitigate fish farm waste was assessed by monthly analyses for one year. A monthly monitoring from July 2020 to October 2021 of physico-chemical and biochemical variables of the water column and the sediment was performed in an in-shore mariculture plant located in the Mar Grande of Taranto (Italy), comparing two adjacent areas that differ in type of farming. The first (reference site) is a fish monoculture, while the second consists of an innovative Integrated Multi-Trophic Aquaculture system (IMTA site). The annual cycle of chlorophyll-a concentration showed values corresponding to mesotrophic/eutrophic conditions, with peak production in early fall (4.64 μg L−1). During the spring and summer sampling times, when the amount of aquaculture waste is greater than during the rest of the year, the reference site showed the highest lipid (151.73 μg L−1) and organic matter (189.00 mg g−1) values with respect to those at the IMTA site. The IMTA bioremediating organisms possibly acted as underwater gardens changing the seston quality and availability and providing protection and food for the zooplankton community, which showed higher abundance of individuals for most sampling times at the IMTA site, peaking during September and October in both 2020 and 2021 (max 232,985.20 ind m−3). Our results demonstrate the effectiveness of the considered IMTA system in mitigating the negative impact of organic matter release into the environment due to fish farming activities. The influence of bioremediating organisms on seston composition and concentration opened up mitigation as well as restoration scenarios.

Biofloc Formation Strategy Effects on Halophyte Integration in IMTA with Marine Shrimp and Tilapia

The incorporation of aquaponics into saline integrated multitrophic aquaculture (IMTA) systems, employing biofloc technology (BFT), relies on the cultivation of halophytes capable of withstanding the physical–chemical conditions created by the unique microbial communities in BFT systems. This study aimed to evaluate the integration of the halophyte Salicornia neei with tilapia (Oreochromis niloticus) and marine shrimp (Litopenaeus vannamei) reared in BFT systems dominated by chemoautotrophic (CHE) and heterotrophic (HET) microorganisms over a period of 84 days in southern Brazil. Each BFT treatment had three replicates, composed of IMTA units. The stocking densities were 400 ind. m−3 (17 m3 circular tanks), 44 ind. m−3 (4 m3 circular tanks), and 30 ind. m−2 (4.8 m2 hydroponic benches) for shrimp, fish, and halophyte, respectively. The highest S. neei individual shoot production (up to 31 g per 30 days) was observed in the CHE treatment, along with favorable agronomic characteristics, possibly due to overall elevated nitrate (98.41 mg N−NO3 L−1) and phosphate concentrations (4.62 P−PO4 L−1). Shrimp in the CHE treatment displayed higher average final weight, specific growth rate, productivity, and survival (11.24 g, 2.88% day−1, 3.86 kg m−3, and 90%, respectively) compared to the HET treatment. Results indicated no significant difference in tilapia zootechnical performance between treatments.

In Vitro Potential of Antioxidant Extracts from Gracilaria gracilis Cultivated in Integrated Multi-Trophic Aquaculture (IMTA) for Marine Biobased Sector

This study aimed to evaluate the antioxidant activity of bioactive compounds extracted from Gracilaria gracilis cultivated in an integrated multi-trophic aquaculture (IMTA) system by different extraction solvents and to investigate the potential capacity of the extracts in cellular systems against environmental pollutants. The global yields, total polyphenol contents, and antioxidant activity were assessed on G. gracilis by DPPH radical scavenging activity, comparing the antioxidant extraction efficiency of the different solvents (ethanol 80%, acetone 70%, N-hexane, and water). Ethanol extract, granted by the highest extractive yield and antioxidant capacity, was tested in vitro in the Sparus aurata fibroblast (SAF-1) cell line to evaluate its protective role against oxidative stress induced by the chemical flame retardant 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47). The results demonstrate that the cells pretreated with G. gracilis extract were protected against oxidative stress and had improved cell viability, cellular antioxidant defense system, and cell cycle control, as demonstrated by the gene expression on some biomarkers related to the cell cycle (p53) and oxidative stress (nrf2, sod, and cat). These results confirm that bioactive compounds obtained from seaweeds cultivated in IMTAs could contribute to producing high-value ingredients that are able to counteract environmental stressors, for the growth of the marine biobased industrial sector and the expansion of new value chains.

The seaweed Chaetomorpha linum cultivated in an integrated multitrophic aquaculture system: A new tool for microplastic bioremediation?

Microplastics (MPs) are emerging pollutants with detrimental impacts on ecosystems and human health. Due to their adverse effects, new strategies to mitigate MP pollution in the marine environment need to be developed urgently. In this context, the capability of the seaweed Chaetomorpha linum (Chlorophyta, Cladophorales) to trap MPs, as well as the effectiveness of a simple washing procedure to clean up the harvested seaweed biomass, were investigated. This algal species was grown in an integrated multitrophic aquaculture system (IMTA), where bioremediator organisms such as macroalgae, polychaetes, sponges and mussels were farmed in the vicinity of the fish cages. MPs trapped in C. linum were classified based on shape and size, and representative samples of each shape were analysed by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy to evaluate their chemical composition. Fibre MPs were the most abundant (97.3 %), while the size ranged from 0.025 to 2.00 mm, with most samples being in the size range 0.80–1.00 mm. MPs were composed mainly of polypropylene, polystyrene, and polyethylene. They were efficiently removed from the cultured seaweeds by a simple density separation procedure, consisting of three extractions with hypersaline solutions of sodium chloride. These results suggest that C. linum cultivated in an IMTA system can be proposed as a bioremediator to capture MPs from the surrounding environment. At the same time, harvested and cleaned green seaweeds may be considered a co-product of the bioremediation process and can find application in several biotechnological fields, including the use as a food source for human consumption.

Cytotoxicity, chemical, and nutritional profile evaluation of biomass extracts of the Lemna aequinoctialis (duckweed) aquatic plant

ABSTRACT Lemna aequinoctialis (duckweed) is the smallest and fast-growing aquatic plant species producing protein-rich biomass with high protein nutritional value, phytoremediation capacity, and nutrient removal from wastewater. Duckweed may also be used as a new potential bioreactor for biological products, such as vaccines, antibodies, and pharmaceutical proteins. Based upon the potential importanc of L. aequinoctialis in phytoremediation and as a bioreactor the aim of this study was to (1) characterize the chemical and nutritional profiles of L. aequinoctialis biomass utilizing an integrated multi-trophic aquaculture system (IMTA) and a pond, and (2) investigate the cytotoxic potential of different concentrations of organic extracts and fractions using the MTT bioassay. EDXRF and ICP-MS analyses indicated the presence of trace elements in lower amounts in relation to the biomass of L. aequinoctialis in the lagoon, emphasizing the importance of plant inclusion management to reduce bioaccumulation of these elements. Analysis of mineral profiles, fatty acids, and amino acids indicated a satisfactory nutritional composition for the use of biomass as a bioproduct. Pigment analysis showed a high concentration of carotenoids, especially astaxanthin. After standardizing the controls, the MTT cell viability test was carried out utilizing rat hepatoma cell line (HTC), which are metabolizing cells that were treated with aqueous or ethanolic extracts and the dichloromethane, ethyl acetate, and methanol fractions at different concentrations. No apparent cytotoxic potential was observed following treatments, since there was no significant reduction in cell viability. Therefore, this study provides information regarding the biomass of L. aequinoctialis derived from the IMTA system, which might support further research into the application of this species as a bioproduct.

Understanding Carbon Footprint in Sustainable Land-Based Marine Aquaculture: Exploring Production Techniques

In aquaculture, it is crucial to understand and mitigate the carbon footprint for sustainable production. As demand for seafood increases, various production techniques compete for an eco-friendly status. This review examines the carbon footprint of various land-based marine aquaculture systems, highlighting their environmental impact. Through exploring innovations and best practices, it navigates the complexities of reducing emissions and promoting carbon sequestration. Some proposals for this purpose are based on diversification through low-trophic-level species, the preservation of high-carbon sequestration sites, polyculture, organic aquaculture and improvements in nutrition, feeding, waste and energy management. In this sense, some land-based aquaculture systems are progressively adapting and updating their zootechnical procedures. Recirculating Aquaculture Systems (RASs) offer interesting advantages such as water conservation, pollution reduction and biosecurity. Integrated Multi-Trophic Aquaculture systems (IMTAs) aim to address two major issues in aquaculture: efficient water usage and the environmental impact of effluents, which are rich in organic particles and dissolved nutrients from undigested food and feces; hence, these systems involve cultivating multiple species (polyculture). Biofloc Technology (BFT) is based on the formation of bioflocs in a culture medium. These systems can enhance feeding efficiency and waste management, thus optimizing nutrient utilization and minimizing environmental impact, achieved through reduced water and fertilizer usage. Traditional (extensive) aquaculture systems operate with minimal input of feed and chemicals, relying heavily on the natural productivity of the ecosystems; thus, the need for manufactured feed, the environmental impact associated with feed production and the transportation and overall costs are significantly reduced. Overall, while RASs, BFT and extensive systems in general offer significant sustainability benefits, IMTA’s holistic approach to ecosystem management and nutrient recycling makes it, in our estimation, the most effective method in terms of ecological footprint in aquaculture. However, its quantitative evaluation is extremely complex, and there is currently a lack of references about its global carbon footprint. Therefore, further research and development are required, as well as collaboration and knowledge-sharing among stakeholders.

Ulva lactuca changed bacteria community structure and enhanced nitrogen removal capability in a shrimp-sea cucumber-crab-algae integrated multi-trophic aquaculture (IMTA) system

Ulva lactuca changed bacteria community structure and enhanced nitrogen removal capability in a shrimp-sea cucumber-crab-algae integrated multi-trophic aquaculture (IMTA) system

Physiological effects of feeding whiteleg shrimp (Penaeus vannamei) with the fresh macroalgae Chaetomorpha clavata

In shrimp farming, the use of commercial feed can generate high nutrient loads in water bodies, and often constitute the most substantial component of production costs. Alternatives that seek to reduce the use of commercial feed can therefore both mitigate environmental impacts and reduce operational expenses. One possible strategy is incorporation of algae that crustaceans can consume with minimal biological effect into integrated multi-trophic aquaculture (IMTA) systems. Our objective was to determine whether the marine shrimp Penaeus vannamei feeds on the fresh macroalga Chaetomorpha clavata and whether the partial substitution (50 %) of this alga in its diet influences its physiology. Survival, growth, and a range of physiological processes including ingestion, defecation, metabolism, nitrogen excretion, oxidized energy substrate, hepatosomatic index, and energy budget were assessed in P. vannamei shrimp fed commercial feed (100 %, control) versus shrimp fed a combination of commercial feed and algae (50 % each). Our results showed that P. vannamei fed on C. clavata, and that there were no significant differences in mortality and growth rates (∼11 %) between shrimp fed with the two diets. The ingestion rate was higher in the group fed with macroalgae, however the defecation rate and digestibility were not affected. In both groups, no differences were detected in metabolic rates, growth, nitrogenous excretion, and egestion between shrimp fed the different diets, nor in oxidized energy substrates and the hepatosomatic index. Our results show that substituting 50 % of the feed with C. clavata represents a viable alternative to full commercial feed since it had minimal impact on the physiological functions of P. vannamei. In addition to the economic benefit of reducing the amount of feed used during culture, the use of algae also reduces contamination of effluent water, thereby improving environmental sustainability and water quality.

A traits-based approach to assess aquaculture’s contributions to food, climate change, and biodiversity goals

Aquaculture has the potential to support a sustainable and equitable food system in line with the United Nations Sustainable Development Goals (SDG) on food security, climate change, and biodiversity (FCB). Biological diversity amongst aquaculture organisms can drive diverse contributions to such goals. Existing studies have assessed the performance of a limited number of taxa in the general context of improving aquaculture production, but few explicitly consider the biological attributes of farmed aquatic taxa at the FCB nexus. Through a systematic literature review, we identify key traits associated with FCB and evaluate the potential of aquaculture to contribute to FCB goals using a fuzzy logic model. The majority of identified traits are associated with food security, and two-thirds of traits linked with food security are also associated with climate change or biodiversity, revealing potential co-benefits of optimizing a single trait. Correlations between FCB indices further suggest that challenges and opportunities in aquaculture are intertwined across FCB goals, but low mean FCB scores suggest that the focus of aquaculture research and development on food production is insufficient to address food security, much less climate or biodiversity issues. As expected, production-maximizing traits (absolute fecundity, the von Bertalanffy growth function coefficient K, macronutrient density, maximum size, and trophic level as a proxy for feed efficiency) highly influence a species’ FCB potential, but so do species preferences for environmental conditions (tolerance to phosphates, nitrates, and pH levels, as well as latitudinal and geographic ranges). Many highly farmed species that are typically associated with food security, especially finfish, score poorly for food, climate, and biodiversity potential. Algae and mollusc species tend to perform well across FCB indices, revealing the importance of non-fish species in achieving FCB goals and potential synergies in integrated multi-trophic aquaculture systems. Overall, this study provides decision-makers with a biologically informed assessment of desirable aquaculture traits and species while illuminating possible strategies to increase support for FCB goals. Our findings can be used as a foundation for studying the socio-economic opportunities and barriers for aquaculture transitions to develop equitable pathways toward FCB-positive aquaculture across nuanced regional contexts.