Environmental impact of marine fish cages at Melenara Bay (Gran Canaria Island, Spain) (Spanish text).

摘要

In the last years the development of expanding aquaculture farming was related with an increasing environmental attention because of the nature of the activity and the historic moment in which it happens.; In fish cages culture, wastes come finally from the food and are directly loaded to the environment.; The environmental impact studies are essential for the aquaculture success and could be based in different points of view and methodologies.; The present study joined two perspectives, a nutritional approach based in wastes quantification related with food ingestion, and a chemical approach, based in the analysis of sediments beneath the cages.; Results of the nutritional approach showed that 120 kg of Nitrogen and 16.8 kg of Phosphorus are loaded for tonne of fish produced at Melenara Bay. Results of the chemical approach showed that no noticeable changes succeed, no significant differences were observed in particle size and Phosphorus content in sediments, but a slight increase of organic matter and nitrogen contents, possibly due to the water current regime in the area.; The minimisation of environmental impact produced by the fish cage culture are related to the adequate site selection, the management of feeding and the use of food with formulation and production oriented to the preservation of the environment.