The integrated culture of seaweed, abalone, fish and clams in modular intensive land-based systems: I. Proportions of size and projected revenues

Three environmentally friendly modular designs for integrated mariculture are described. The basic design consists of modules for the culture of seaweed (Ulva lactuca or Gracilaria spp.) and abalone (Haliotis tuberculata). Modules for the culture of fish (Sparus aurata) and then clams (Tapes philippinarum) are subsequently connected in two progressively complex systems. The modular design allows flexibility in the allocation of resource shares to each product according to operational and economic constraints. Reduction in nutrient release to the environment results from increasing the fraction of supplied ammonia or protein-N that ends up as commercial products relative to current monoculture practices. As much as half or more of the nitrogen supplied to the proposed systems is expected to be utilized by harvestable yields of seaweed, molluscs and fish. System dimensions and projections of yields and revenues allow readers to roughly estimate profitability for the three designs under their own conditions.