Dry sludge in beds

How is the evidence assessed?
  • Effectiveness
    not assessed
  • Certainty
    not assessed
  • Harms
    not assessed

Study locations

Key messages

  • Two replicated trials in Canada found sludge drying beds removed phosphorus from freshwater fish farm sludge.

About key messages

Key messages provide a descriptive index to studies we have found that test this intervention.

Studies are not directly comparable or of equal value. When making decisions based on this evidence, you should consider factors such as study size, study design, reported metrics and relevance of the study to your situation, rather than simply counting the number of studies that support a particular interpretation.

Supporting evidence from individual studies

  1. Two replicated experiments in Quebec, Canada in 2009 (Puigagut et al., 2011) found that treatment of freshwater fish farm sludge with sludge drying beds removed 95- 99% of total phosphorus (TP). The first experiment showed there was no difference in total phosphorus removed between sludge loading. The second experiment found that phosphorus leaching from sludge drying beds was 5 μg TP released per gram of total phosphorus regardless of sludge loading. For the first experiment, four sludge drying beds were set up at a rainbow trout farm; each consisted of a 1m2 reservoir filled with different types of river gravel (20cm) and a top layer of sand (20cm). Typha latifolia was planted on the sludge drying bed one year before the experiment at a density of 8 plants m2. During the experiment, the sludge drying beds were fed once a week with sludge from the fish farm at two concentrations (32 or 18 kg of dry matter per m2 year). The second experiment in a laboratory aimed to determine phosphorus leaching using 2L beakers containing 0.5L of sludge and 1.4 L of filtered pond water. Phosphate concentrations in sludge and pond water were monitored.

    Study and other actions tested
Please cite as:

Jones, A.C., Mead, A., Austen, M.C.V.  & Kaiser, M.J. (2013) Aquaculture: Evidence for the effects of interventions to enhance the sustainability of aquaculture using Atlantic salmon (Salmo salar) as a case study. Bangor University


Where has this evidence come from?

List of journals searched by synopsis

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Sustainable Aquaculture

This Action forms part of the Action Synopsis:

Sustainable Aquaculture
Sustainable Aquaculture

Sustainable Aquaculture - Published 2013

Atlantic salmon Aquaculture Synopsis

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