Open AccessExperimental Evaluation of the Halophyte, Salicornia virginica , for Biomitigation of Dissolved Nutrients in Effluent from a Recirculating Aquaculture System for Marine Finfish
Author(s) -
Watanabe Wade O.,
Farnell Robert D.
Publication year - 2018
Publication title -
journal of the world aquaculture society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.655
H-Index - 60
eISSN - 1749-7345
pISSN - 0893-8849
DOI - 10.1111/jwas.12490
Subject(s) - lysimeter , halophyte , nutrient , effluent , biology , salinity , aquaculture , environmental chemistry , agronomy , environmental science , chemistry , environmental engineering , fishery , ecology , soil water , fish <actinopterygii>
The ability of the halophyte, Salicornia virginica , planted in drainage lysimeters to biomitigate dissolved nutrients in effluent from a recirculating aquaculture system (RAS) for marine finfish was evaluated. Seawater effluent from a RAS producing black sea bass, Centropristis striata (filtered to reduce total suspended solids), was used as irrigant. Plant growth and dissolved N and P removal were determined as a function of leachate fraction (LF%) – that is, proportion of irrigant that leaches from the plant‐substrate lysimeter. Lysimeters were irrigated weekly to produce 30, 40, and 50% LF. A control (unplanted) lysimeter was included at the 30% LF. Plant growth was excellent in all LF% treatments until Day 141 when salt buildup in the lysimeter substrate inhibited nutrient uptake. Salt accumulation was mitigated at higher LF%, so that plant biomass and net removal (μg) of dissolved N and P by the p‐s lysimeter remained higher ( P < 0.05) at the 40 and 50% than at the 30% LF. On Day 141, percent removal efficiency at the 50% LF was 79.2% for inorganic N and 73.9% for total phosphorus. Through Day 355, substrate salinity was minimized and plant biomass and nutrient removal were maximized at the 50% LF. S. virginica is an effective biofilter for dissolved nutrients in effluent from an RAS for marine finfish.