įish polyculture is the production of two or more species in the same physical space at the same time. Third, there is now a strong societal expectation to ensure animal welfare, which may be negatively impacted by intensive production. Second, monoculture has also been criticized from human food security and economic viewpoints, as it might have a low resilience and a low adaptative potential to face changes in environmental and socio-economic contexts. First, it can limit the food conversion ratio, which compromises the water quality of the system by increasing nutrient concentration (generated by non-digested feed) in the effluents. However, monoculture may have several limitations. In Western countries, intensive monoculture (i.e., production of a single species in cages, recirculated aquaculture systems, or ponds) has been favored in aquaculture development. However, in recent years, aquaculture has become an increasingly important sector for this supply because wild fisheries are no longer able to meet the demand for aquatic products. Until the early 2010′s, the global supply of aquatic products was mainly provided by fisheries. Human nutrition partially relies on aquatic organisms. In the coming decades, the human demand for food products is expected to double, due to world population growth. This highlights the need to carefully consider stakeholder priorities when choosing fish polycultures. A comparison of our procedure results between these scenarios showed that the ranking changed for candidate polycultures in two test cases. Three scenarios of stakeholder priorities were considered for weighting evaluation results: placing a premium on production, welfare, or both for the target species. These benefits were evaluated based on survival rate as well as morphology, behavioral, and physiological traits. For each test case, our procedure aimed at ranking alternative combinations according to their benefits for production and/or welfare of the target species. These test cases each focused on a target species (two on Sander lucioperca and one on Carassius auratus), which were reared in two or three different alternative candidate fish polycultures. We applied our procedure on three test cases of fish polycultures in recirculated aquaculture systems. This procedure aims at successively (i) weighting evaluation results obtained for each candidate polyculture according to stakeholder priorities (ii) assessing differentiation between candidate species combinations based on these weighted results and (iii) ranking differentiated candidate polycultures. Here, we proposed a ranking procedure of candidate fish polycultures (i.e., species combinations that could be potentially interesting for aquaculture) based on a multi-trait assessment approach and the stakeholder priorities. Moreover, in order to ensure the relevance of such a procedure, it is important to integrate the socio-economic expectations by assigning relative weights to each trait according to the stakeholder priorities. This requires the development of a ranking procedure, based on a multi-trait assessment, that highlights the most suitable species combinations for polyculture. One way to maximize the benefits of polyculture is to combine species with high levels of compatibility and complementarity. Nevertheless, it may result in beneficial as well as detrimental consequences for fish production. Polyculture is a potentially interesting rearing practice for future aquaculture developments.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |