New pathways for organic waste in land-based farming of salmon

Sandvold, Hilde Ness; Gregg, Jay Sterling; Olsen, Dorothy Sutherland

doi:10.4324/9780429460289-8

Cited by 3 publications

(4 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Land-based (indoor) recirculating aquaculture systems (RAS) enable intensive production under controlled conditions with drastically reduced water consumption compared to traditional production forms [39,40]. They further allow the effective collection and subsequent valorization of aquaculture sludge, currently through biogas production or application as agricultural fertilizer [41,42]. The natural extension of RAS is represented by aquaponic systems [43][44][45], which make use of the dissolved nutrients accumulated in the recirculating water of RAS through hydroponic plant production by permanent or on-demand coupling of RAS and hydroponic units [46].…”

Section: Introductionmentioning

confidence: 99%

Fish Feeds in Aquaponics and Beyond: A Novel Concept to Evaluate Protein Sources in Diets for Circular Multitrophic Food Production Systems

2022

View full text Add to dashboard Cite

With the general objective of optimizing internal nutrient recycling, circular multitrophic food production systems, e.g., combining fish, plant, and insect larvae production, rely on the quality and composition of sustainable nutritional inputs. Therefore, differences in dissolved and solid nutrient excretion patterns produced by Nile tilapia (Oreochromis niloticus) reared in recirculating aquaculture systems (RAS) with 5% daily water exchange and fed black soldier fly meal (BSFM), poultry by-product meal (PM), poultry blood meal (PBM) and fish meal (FM) as single protein sources were investigated to evaluate the potential for creating specific fish meal-free diets. Fish fed the FM and PM diet showed the significantly best (p < 0.05) and among each other similar (p > 0.05) growth performance (specific growth rate (SGR): 2.12 ± 0.04/2.05 ± 0.11; feed conversion ratio (FCR): 0.86 ± 0.03/0.92 ± 0.01), whereas the PBM diet caused significantly reduced performance (SGR: 1.30 ± 0.02; FCR: 1.79 ± 0.05) in comparison to the FM/PM diet as well as the BSF diet (SGR: 1.76 ± 0.07; FCR: 1.11 ± 0.05). The FM and PM diet resulted in a faster increase and significantly higher dissolved nitrogen and phosphorus levels, while the BSF diet caused faster accumulation and significantly elevated levels of dissolved potassium, magnesium, and copper. The PBM diet resulted in the feces with the significantly highest nutrient density (gross energy, crude protein, and amino acids) but overall much lower dissolved nutrient levels in the water. Results are discussed with regard to implications for developing circular multitrophic food production systems.

show abstract

Section: Introductionmentioning

confidence: 99%

Fish Feeds in Aquaponics and Beyond: A Novel Concept to Evaluate Protein Sources in Diets for Circular Multitrophic Food Production Systems

2022

View full text Add to dashboard Cite

show abstract

“…This may especially be true in sludge from commercial RAS operation, where a certain amount of feed loss is practically inevitable. Currently, aquaculture sludge is predominantly used for biogas production or as agricultural fertilizer [99,100]. However, various studies have begun investigating the potential of recycling aquaculture sludge into higher value nutrients through vermicomposting [101,102], polychaetes [103,104] or insect larvae [105].…”

Section: Solid Nutrientsmentioning

confidence: 99%

Closing Nutrient Cycles through the Use of System-Internal Resource Streams: Implications for Circular Multitrophic Food Production Systems and Aquaponic Feed Development

et al. 2023

View full text Add to dashboard Cite

In order to further close nutrient cycles of aquaponic systems, it could be possible to integrate a third trophic level in the form of insect larvae production (i.e., black soldier fly larvae) to recycle internal waste streams into valuable nutrients. This would present opportunities to formulate sustainable circular aquafeeds that combine these internally available nutrients with complementary external raw materials. The ingredient composition of feeds for such circular multitrophic food production systems (CMFS) may affect fish performance as well as excretion of important dissolved plant nutrients such as N, P and K. Hence, fish meal from catfish processing (CM) as base ingredient was combined with variable levels of poultry by-product meal (PM) and black soldier fly larvae meal (BSFM) into three marine-ingredient-free experimental diets corresponding to hypothetical production scenarios of a CMFS that aims to integrate aquaponics with insect larvae production. These experimental diets and a commercial diet (COM) were compared using isonitrogenous and isolipidic formulations. They were fed to African catfish (Clarias gariepinus) in recirculating aquaculture systems (RAS) and evaluated concerning growth performance and nutrient excretion. All diets resulted in similar total inorganic nitrogen (TIN) excretion, whereas the increase of dietary PM inclusion from 0% (BSF diet) to 20% (MIX diet) and to 41% (PM diet) and concomitant reduction of BSFM inclusion led to increasingly higher soluble reactive phosphorus (SRP) excretion per unit of feed compared to the COM diet. While the PM diet enabled the best growth and feed conversion performance, the MIX and especially the BSF diet produced more similar performance to the COM diet, which generated the highest dissolved K excretion. The MIX and the PM diet resulted in the highest Ca and P, yet lower N content in the fish feces. Results indicate that combining CM with elevated levels of PM in the diet of African catfish could improve growth performance and reduce the need for P fertilization in aquaponics when compared to industrial diets optimized for low environmental impact. Findings are discussed regarding their implications for CMFS and aquaponic feed formulation.

show abstract

“…The pathways for transforming sludge into a useful fertilizer product are still in a nascent stage and are unlikely to be able to handle the expected sudden increase in volume of organic waste if sludge collection becomes a standard practice (Sandvold et al, 2019). The 10.3389/fsufs.2023 Frontiers in Sustainable Food Systems 10 frontiersin.org current infrastructure for sludge treatment in Norway is capable of handling only small amounts of sludge.…”

Section: Strategies For Improving Aquatic P Usementioning

confidence: 99%

“…Overall, addressing these barriers and challenges requires collaboration among stakeholders, including fish producers, biogas producers, fertilizer manufacturers, transportation networks, and regulatory bodies, to develop effective solutions and frameworks for the utilization of fish sludge-based fertilizers (Sandvold et al, 2019).…”

Section: Strategies For Improving Aquatic P Usementioning

confidence: 99%

Circular economy for aquatic food systems: insights from a multiscale phosphorus flow analysis in Norway

Pandit,

Dittrich,

Strand

et al. 2023

Front. Sustain. Food Syst.

View full text Add to dashboard Cite

As wild-caught fish become scarce, feed ingredients for farming fish, such as salmon, are increasingly sourced from agricultural plants that depend on mineral fertilizers. Since these fish are naturally carnivorous, they have difficulty digesting the phosphorus in plant-based feed. So additional phosphorus supplements are added to the feed, resulting in a disproportionate increase in mineral phosphorus use and emission. Aquatic food production is increasingly relying on agriculture and mineral phosphorus resources. The feed surplus and the excreta are seldom collected and recycled, leading to a massive loss of nutrients to water bodies and the seafloor, resulting in local risk for eutrophication. Norway currently produces more than half of the world’s Atlantic salmon, and it is set to increase production from currently 1.5 to 5 Mt. in 2050. This has large implications for feed supply and emissions globally. There is a lack of studies that analyze the phosphorus system in aquatic food production at a sufficient spatial and temporal granularity to effectively inform interventions for a more circular use of phosphorus. Here, we present a multi-scale phosphorus flow analysis at monthly resolution ranging between 2005 and 2021 for aquatic food production in Norway and quantitatively discuss the effectiveness of alternative strategies for improving resource efficiency. The results indicate that P emissions from aquaculture have nearly doubled in the period between 2005 and 2021. The P use efficiency (PUE) in Norwegian aquaculture was 19% in 2021. The addition of phytase to the feed could improve the PUE by 8% by reducing P supplements and emissions by 7 kt/y. The use of Integrated Multi-Trophic Aquaculture close to fish farming sites could absorb emissions by 4 kt/y by creating new marine food products. Sludge collection systems could reduce P emissions by 4 to 11 kt/y, depending on the technology. Using the sludge in local agriculture would exacerbate the current P accumulation in soils close to the coastline, given that the animal density in this region is already high. Hence, a large and sophisticated processing infrastructure will be needed to create transportable, high-quality secondary fertilizers for effective sludge recycling in regions with a P deficit.

show abstract

New pathways for organic waste in land-based farming of salmon

Cited by 3 publications

References 8 publications

Fish Feeds in Aquaponics and Beyond: A Novel Concept to Evaluate Protein Sources in Diets for Circular Multitrophic Food Production Systems

Fish Feeds in Aquaponics and Beyond: A Novel Concept to Evaluate Protein Sources in Diets for Circular Multitrophic Food Production Systems

Closing Nutrient Cycles through the Use of System-Internal Resource Streams: Implications for Circular Multitrophic Food Production Systems and Aquaponic Feed Development

Circular economy for aquatic food systems: insights from a multiscale phosphorus flow analysis in Norway

Contact Info

Product

Resources

About