Avaliação da qualidade da água de igarapés com criação de matrinxã Brycon amazonicus (Spix & Agassiz, 1829) na zona rural de Rio Preto da Eva e Manaus-AM

Abstract

It analyzed fish farming implanted in streams in the rural area of Manaus and Rio Preto da Eva.In Amazonas this modality has been highlighted as an important economic activity, indicated with a promising alternative for the region.The building modules are deployed in the stream bed itself or by derivation constructed in permanent preservation areas (PPA), coated wood, tires, fabrics and other materials such as reinforced concrete and has as main species matrinxã.In the properties are developed other activities unrelated to fish farming and all make multiple use of water.In order to evaluate the quality of the water in relation to the physical and chemical characteristics of the water of streams with fish farming, a limnological survey was carried out on this kind of projects in the years of 2012, 2016 and 2017, upstream, downstream and 100 meters downstream of the creation module.The samples were sent to the Laboratory of Limnology where they were analyzed according to the Standard Methods for the Examination of Water and Wastewater- APHA (2005).Significant differences were observed only for ammonia and orthophosphate between upstream and downstream of the criating modules. The trophic status index in 50% of the monitored properties were classified as oligotrophic, 100% as mesotrophic and 37,5% as eutrophic.Total phosphorus and dissolved oxygen values presented in some cases disagreement with the limits established by law. Changes in water quality are most noticeable in modules deployed by deviation from the runway, by renewal time account of water in it. The EIT has proved to be an important tool in monitoring the degree of trophic of streams used in fish farming , indicating the quality of used water and the effluent that is continuously released. Thus, it can be an important instrument for the management of water resources, in order to promote public policies aimed at resolving conflicts by multiple uses.