Performance of polychaete assisted sand filters under contrasting nutrient loads in an integrated multi-trophic aquaculture (IMTA) system

Abstract

Polychaete assisted sand filters (PASFs) allow to combine a highly efficient retention of particulate organic matter (POM) present in aquaculture effluent water and turn otherwise wasted nutrients into valuable worm biomass, following an integrated multi-trophic aquaculture (IMTA) approach. This study evaluated the bioremediation and biomass production performances of three sets of PASFs stocked with ragworms (Hediste diversicolor) placed in three different locations of an open marine land-based IMTA system. The higher organic matter (OM) recorded in the substrate of the systems which received higher POM content (Raw and Df PASFs – filtered raw and screened by drum filter effluent, respectively) likely prompted a superior reproductive success of stocked polychaetes (final densities 2–7 times higher than initial stock; ≈1000–3000 ind. m−2). Bioremediation efficiencies of ≈70% of supplied POM (≈1.5–1.8 mg L−1) were reported in these systems. The PASFs with lower content of OM in the substrate (Df + Alg PASFs – filtered effluent previously screened by drum filter and macroalgae biofilter) differed significantly from the other two, with stocked polychaetes displaying a poorer reproductive success. The PASFs were naturally colonized with marine invertebrates, with the polychaetes Diopatra neapolitana, Terebella lapidaria and Sabella cf. pavonina being some of the species identified with potential for IMTA.

RETRACTED: Advantage of Species Diversification to Facilitate Sustainable Development of Aquaculture Sector

“…A recent report suggested that dog conch (Laevistrombus canarium) ably adapts to different environmental conditions and has a high growth rate, making it a favorable IMTA species and able to be co-cultured with sea urchins and abalone in seawater or with saltwater tilapia in land-based aquaculture [113]. Moreover, the IMTA approach is most appropriate to promote a circular economy on the basis of the economic viability of integrated aquaculture species [114] like filter feeders [115], particularly shellfish or mollusks [116].…”

Evaluating the Bioremediation Capacity of the Polychaete Perinereis gualpensis (Jeldes, 1963) for Atlantic Salmon Aquaculture Sludge

“…Incorporating polychaetes in bioremediation processes can potentially recycle proteins and polyunsaturated fatty acids present in aquaculture sludge. Several studies showed that certain species of polychaetes, such as Perinereis nuntia vallata, Abarenicola pusilla, and Hediste diversicolor can assimilate nitrogen, organic carbon, and increase their lipid content when fed with specific types of aquaculture sludge [21,[28][29][30][31][32][33]. These appreciated components can be incorporated into aquaculture feeds, thus reducing dependence on scarcer traditional ingredients such as fishmeal and fish oil.…”

Effects of dietary various oil sources on zootechnical performance, sexual maturation, whole‐body proximate composition and fatty acid profile of Hediste diversicolor

“…In the last two decades, H. diversicolor has been widely used in an integrated recirculating aquaculture system to bioremediation wastewater, recreational fishing (Bischoff et al, 2009; Pajand et al, 2017; Yousefi‐Garakouei et al, 2019). Many researchers turned their attention to polychaetes in aquafeeds due to the high content of unsaturated fatty acids, namely eicosapentaenoic acid (EPA: 20:5n‐3) and docosahexaenoic acid (DHA: 22: 6n‐3) (Bischoff et al, 2009; Leelatanawit et al, 2014; Wang et al, 2019) and arachidonic acid (ARA: 20:4 n‐6) (Jerónimo et al, 2020; Marques et al, 2019). H. diversicolor worms contain phospholipids, hormones like prostaglandin and thromboxane (Meunpol et al, 2010).…”