Location: Natural Products Utilization ResearchTitle: Comparison of phytoplankton communities in catfish split-pond aquaculture systems with conventional ponds Author
|Tucker, Craig - Us Department Of Agriculture (USDA)|
|Brown, Travis - Us Department Of Agriculture (USDA)|
|Torrans, Eugene - Us Department Of Agriculture (USDA)|
|Whitis, Gregory - Auburn University|
Submitted to: North American Journal of Aquaculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/6/2016
Publication Date: 9/2/2016
Publication URL: http://handle.nal.usda.gov/10113/5801787
Citation: Schrader, K., Tucker, C.S., Brown, T.W., Torrans, E.L., Whitis, G.N. 2016. Comparison of phytoplankton communities in catfish split-pond aquaculture systems with conventional ponds. North American Journal of Aquaculture. 78:384-395.
Interpretive Summary: Novel split-pond systems are being used more frequently by catfish producers in the southeastern United States. The study determined that phytoplankton communities differ little in type and abundance compared to those present in conventional catfish ponds that producers have utilized in the past. Subsequently, catfish farmers can utilize similar management practices for pond water quality and for undesirable species of cyanobacteria (blue-green algae) in split-ponds as to those used for conventional ponds.
Technical Abstract: There has been a growing interest and use of variations of partitioned aquaculture systems (PAS) in recent years by the southeastern United States of America farmed catfish industry. Split-pond systems, one type of PAS, are designed to better manage fish waste byproducts (e.g., ammonia) and dissolved oxygen levels than the conventional earthen ponds that have been utilized by farmers for many decades. Recent studies have focused on design, water flow rates, and other management areas of catfish split-ponds, but there has so far not been a focused examination of phytoplankton community composition and biomass in these split-ponds. In the current study, pond water samples were collected from split-ponds at a research facility in west Mississippi and at a commercial farm in west Alabama approximately every three weeks during the fish grow-out period (May to November). Water samples were analyzed for chlorophyll a concentration (phytoplankton biomass) of several major phytoplankton divisions and for types of phytoplankton and their abundance. Overall, chlorophyll a concentrations in the split-ponds were maintained within the typical range (0-800 µg/L) found in non-PAS (conventional) catfish ponds. The phytoplankton communities in split-ponds were dominated by cyanobacteria or blue-green algae (Cyanophyta) and by the same common species of cyanobacteria (e.g., Planktothrix agardhii, Planktothrix perornata, Microcystis aeruginosa, Raphidiopsis brookii) reported in previous studies for conventional catfish ponds. In addition, many types of phytoplankton in the other major divisions [Chlorophyta (green algae), Bacillariophyta (diatoms), Chrysophyta (golden brown algae), Cryptophyta (cryptomonads), Euglenophyta (euglenophytes), and Pyrrhophyta (dinoflagellates)] present in the split-ponds were the same as those reported previously in conventional catfish ponds. Therefore, issues related to management practices for pond water quality (e.g., dissolved oxygen) and undesirable cyanobacteria are expected to be similar as those used for conventional ponds.