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Published on: October 24, 2025
Carbon cycling in a zero-discharge mariculture system
Kenneth Schneider1, Yonatan Sher, Jonathan Erez
1The Hebrew University of Jerusalem, Faculty of Agricultural, Food and Environmental Quality Sciences, Department of Animal Sciences, P.O. Box 12, Rehovot 76100, Israel.
Water Research
|February 25, 2011
Summary
This study analyzed a zero-discharge mariculture system for gilthead seabream using stable isotopes. Results show intensive microbial degradation in the anaerobic treatment, confirming feed pellets as the sole food source.
Area of Science:
- Aquaculture
- Environmental Science
- Biogeochemistry
Background:
- Increasing seafood demand necessitates sustainable aquaculture.
- Zero-discharge mariculture systems offer a solution to reduce environmental impact.
- Understanding nutrient cycling in these systems is crucial for efficiency.
Purpose of the Study:
- To trace element cycling in a zero-discharge gilthead seabream mariculture system.
- To evaluate the effectiveness of aerobic and anaerobic biofiltration.
- To determine the origin of organic matter and assess microbial activity.
Main Methods:
- Stable isotope analysis (carbon and nitrogen) of water and organic matter.
- Chemical profiling of dissolved inorganic carbon and alkalinity.
- Trace study of a recirculating aquaculture system (RAS).
Main Results:
- Dissolved inorganic carbon and alkalinity were higher in the anaerobic loop.
- The δ13C of dissolved inorganic carbon was depleted in the anaerobic loop.
- Isotope signatures confirmed fish were fed solely on pellets, with sludge showing 15N enrichment due to microbial degradation.
Conclusions:
- The biofiltration system effectively manages water quality.
- Anaerobic treatment facilitates significant organic matter degradation.
- Stable isotopes are valuable tools for monitoring mariculture system processes.
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