Organic matter degradation and redistribution of sediment associated contaminants by benthic invertebrate activities

Meer, Tom V. van der; Verdonschot, P.F.M.; Dokter, Lina; Absalah, Samira; Kraak, Michiel H.S.

doi:10.1016/j.envpol.2022.119455

Cited by 5 publications

(4 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Chironomus larvae almost doubled the sludge degradation compared to the control systems, which is in line with previous work on sludge degradation by Chironomus larvae [ 13 ]. Chironomus larvae could enhance sludge degradation even up to five times, when using higher densities of third instar larvae [ 15 ].…”

Section: Discussionsupporting

confidence: 91%

“…This would indicate that bioturbation and feeding activity are antagonistic processes simultaneously mediated by Chironomus . As previously observed for metals [ 13 ], bioturbation by Chironomus larvae resulted in a greater change in the distribution of P and N in the system than the bioaccumulation within the organisms.…”

Section: Discussionsupporting

confidence: 66%

“…To limit risks associated to bioaccumulation of contaminants [ 55 ], non-food applications are preferred. Bioaccumulation of contaminants in sludge-grown Chironomus seems to be limited, but nonetheless contaminant concentrations did sometimes exceed allowable levels for feed and foodstuff [ 13 ].…”

Section: Discussionmentioning

confidence: 99%

“…As an alternative to technical solutions, we here argue that aquatic organisms have the potential to aid in sludge degradation and nutrient removal, as they also degrade organic matter and take up nutrients, especially nitrogen (N) and phosphorus (P), in their natural environment. Indeed, multiple species of macroinvertebrate collector-gatherers can feed on WWTP sludge, thereby affecting fluxes of nutrients and metals [ 12 , 13 ]. They can also reduce GHG emissions from organically rich sediments, for example through burrowing, thereby oxygenating deeper layers and thus limiting methane (CH 4 ) production and favouring CH 4 oxidation [ 14 ].…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Sludge degradation, nutrient removal and reduction of greenhouse gas emission by a Chironomus-Azolla wastewater treatment cascade

Hendriks,

van der Meer,

Kraak

et al. 2024

PLoS ONE

View full text Add to dashboard Cite

Wastewater treatment plants (WWTPs) are a point source of nutrients, emit greenhouse gases (GHGs), and produce large volumes of excess sludge. The use of aquatic organisms may be an alternative to the technical post-treatment of WWTP effluent, as they play an important role in nutrient dynamics and carbon balance in natural ecosystems. The aim of this study was therefore to assess the performance of an experimental wastewater-treatment cascade of bioturbating macroinvertebrates and floating plants in terms of sludge degradation, nutrient removal and lowering GHG emission. To this end, a full-factorial experiment was designed, using a recirculating cascade with a WWTP sludge compartment with or without bioturbating Chironomus riparius larvae, and an effluent container with or without the floating plant Azolla filiculoides, resulting in four treatments. To calculate the nitrogen (N), phosphorus (P) and carbon (C) mass balance of this system, the N, P and C concentrations in the effluent, biomass production, and sludge degradation, as well as the N, P and C content of all compartments in the cascade were measured during the 26-day experiment. The presence of Chironomus led to an increased sludge degradation of 44% compared to 25% in the control, a 1.4 times decreased transport of P from the sludge and a 2.4 times increased transport of N out of the sludge, either into Chironomus biomass or into the water column. Furthermore, Chironomus activity decreased methane emissions by 92%. The presence of Azolla resulted in a 15% lower P concentration in the effluent than in the control treatment, and a CO2 uptake of 1.13 kg ha-1 day-1. These additive effects of Chironomus and Azolla resulted in an almost two times higher sludge degradation, and an almost two times lower P concentration in the effluent. This is the first study that shows that a bio-based cascade can strongly reduce GHG and P emissions simultaneously during the combined polishing of wastewater sludge and effluent, benefitting from the additive effects of the presence of both macrophytes and invertebrates. In addition to the microbial based treatment steps already employed on WWTPs, the integration of higher organisms in the treatment process expands the WWTP based ecosystem and allows for the inclusion of macroinvertebrate and macrophyte mediated processes. Applying macroinvertebrate-plant cascades may therefore be a promising tool to tackle the present and future challenges of WWTPs.

show abstract

Section: Discussionsupporting

confidence: 91%

Section: Discussionsupporting

confidence: 66%