Management of fish farm sludge in vertical flow treatment wetlands planted with macrophytes: mesocosm experiment

Date

2021

Journal Title

Journal ISSN

Volume Title

Publisher

Tartu Ülikool

Abstract

Inland fish farms are significant sources of water pollution. The main objectives of this work were to: a) develop on-site methods for fish farm sludge management and treatment with modified partly hydraulically saturated vertical flow treatment wetlands (TWs); b) to determine if effective TWs’ plant species, Phragmites australis subsp. australis (invasive in North America), could be replaced with native Phragmites australis subsp. americanus. The performance of 12 on-site mesocosms (both species and unplanted mesocosms in 4 replicates) during two vegetation periods was assessed. The TWs were fed with a batch load of raw sludge, influent and effluent quality and plant development were monitored. Good sludge dewatering and percolate treatment was achieved in TWs (solids removal over 80%; COD 50-70%; TKN and TP 50-60%). As there were no significant differences in efficiency of the sub-species and unplanted mesocosms, the native Phragmites could replace the invasive in TWs. Longer lasting full-scale studies should be done to assess the influence of plants and species choice to the TW performance in order to validate the findings of this experiment.

Description

Keywords

Citation