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Submitted to: http://www.ias.unu.edu/Proceedings/ICIBS/IC-MFA/
Publication Type: Proceedings Publication Acceptance Date: 9/15/2000 Publication Date: 10/13/2000 Citation: Adler, P.R. 2000. Phytoremediation of aquaculture effluents. 2000. In e.L. Foo, T. Della senta, and K. Sakamoto (ed.) Material Flow analysis of Intergrated Bio-Systems. Proc. Internet Conf. on Material flow analysis of Integrated Bio-Systms (March-Oct, 2000) http://www.ias.unu.edu/proceedings/icibs/ic-mfa/ (Procedings). Interpretive Summary: Technical Abstract: This study describes an aquaponic system for the integrated production of rainbow trout and plants. The objective was to reuse water by removal of nutrients in food crops. The microscreen filter removes about 80% of the P excreted by the fish with the biosolids, leaving about 20% of the P in the effluent. A mass balance of system nutrients was conducted and it was determined that it takes 7.5-10 heads of lettuce to remove the P excreted in the effluent by the production of 1 pound of trout or 13-18 heads for each kg of feed consumed. Greenhouse studies demonstrated that by using the conveyor production strategy (CPS), P could be removed to <0.01 mg/L by lettuce without an apparent reduction in production or quality. Conventional thinking regarding the use of food crops to clean effluents has been that plants cannot remove nutrients in water to low levels without a reduction in productivity or quality. If water is distributed in a horizontal plug-flow pattern, all nutrients will be luxury consumed at the inlet, making nutrients limiting at the outlet and significant greenhouse space will be dedicated to growing plants that have no market value. Because greenhouse space is expensive, productivity is critical for a profitable operation. CPS was developed using thin-film technology for plant production in dilute aquaculture effluents. With the CPS, young plants are positioned near the solution inlet and are moved progressively, like along a conveyor belt, towards the outlet as they grow. Luxury consumption by lettuce enabled them to store P in their tissues early in their growth cycle for use later as water P levels decreased and influx could no longer meet current demands. This paper can be found at the following web address: http://www.ias.unu.edu/proceedings/icibs/ic-mfa/ |
