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Email the author (Login required) Effect of the photoperiod and the shrimp-macroalgae rate on removal of total ammonia nitrogen by Gracilaria vermiculophylla, cultivated with Litopenaeus vannamei, without water exchange
DOI: https://doi.org/10.3856/vol41-issue5-fulltext-9
Abstract
A study was conducted to evaluate the effect of the photoperiod and biomass rate of shrimp:macroalgae over the total ammonia nitrogen (TAN) removal by the macroalgae Gracilaria vermiculophylla, in an integrated culture with shrimp Litopenaeus vannamei, with zero water exchange. Four photoperiods were evaluated: 12:12, 14:10, 16:08 and 24:00 h of light:darkness and two biomass ratios 1:4 and 1:8. The experimental design was a factorial of 4x2, with four replicates by treatment. The lowest concentrations TAN (0.55 ± 0.17 mg L-1), N-NO2 (0.145 ± 0.29 mg L-1) y N-NO3 (3.13 ± 0.73 mg L-1) were registered in the biomass rate of 1:8. The highest growth rates of the macroalgae (3.07 ± 1.44% day-1) were recorded with 24:00 h photoperiod and biomass ratio 1:8. The highest rate of N incorporation (0.31 ± 0.12 mg N L-1) of the macroalgae occurred under the same conditions. Shrimp growth was similar to data reported in traditional recirculation systems. The integration of G. vermiculophylla without water exchange system was able to maintain the TAN and N-NO2 under levels conditions for the growth of L. vannamei.
