Periphyton-based aquaculture production: an ecological approach

The expansion of aquaculture must be accomplished by promoting an ecological aquaculture model which brings not only the technical aspects of eco-systems design and ecological principles to aquaculture, but also incorporates comprehensive planning for the wider social, economic and environmental contexts of aquaculture. The ecological aquaculture preserves the form and functions of natural ecosystems, practices trophic level efas the worlds most efprotein producer relying on plant, waste animal or seafood processing wastes, and nutrient management by not discharging any nutrient or chemical pollution and does not contribute to biological pollution (Costa-Pierce, 2002). The ecology of aquaculture ponds consists of a number of interrelated physical, chemical and biological processes. Among them, three basic processes are important: production, consumption and decomposition. The Primary productivity is via an autotrophic pathway in which solar energy is used to convert carbon dioxide into organic matter as plant biomass through photosynthesis. It is the basic food source in an aquaculture pond which is provided by phytoplankton, periphyton and other submerged plants. The secondary food source in aquaculture ponds is the added organic matter in the form of manure and artifeed. In the consumption process, both autochthonous and added organic matters are eaten directly or indirectly by aquatic animals and used as building blocks of biomass and a source of energy. The third and most important ecological process in aquatic food webs is decomposition, a heterotrophic pathway in which micro-organisms breakdown and/or decompose organic matter and produce detritus and/or inorganic nutrients. The inorganic nutrients are recycled to stimulate primary production and serve as the base of autotrophic food webs. However, the novel periphyton-based technology deals with very basic aspects of aquaculture: aquacultural ecology: production, consumption and decomposition in the aquatic production environment (Fig. 1) and how to enhance these processes in favour of sustainable food production for mankind.