Eficiência do aguapé sobre variáveis limnológicas em canais de abastecimento utilizados no cultivo de tambaqui

Abstract

RESUMOO uso de macrófitas aquáticas pode ser uma alternativa para o tratamento e minimização dos efluentes gerados na piscicultura. Objetivou-se com este trabalho verificar a eficiência do aguapé (Eichhornia crassipes) na melhora de variáveis limnológicas (fósforo e amônia) com cultivo de tambaqui (Colossoma macropomum) em canais com fluxo contínuo de água. O experimento foi conduzido por um período de 60 dias com amostragens quinzenais em canais de abastecimento, seccionados com telas e utilizando uma densidade de 120 peixes m-³. As seções foram divididas em etapas, alternando com presença e/ou ausência de aguapé. Não foram constatadas diferenças significativas nos teores de amônia, alcalinidade e dureza do efluente, nos tratamentos com ou sem a presença dos aguapés, contudo foi comprovada a eficiência do aguapé na remoção de nutrientes como o fósforo nas primeiras semanas de cultivo, sendo recomendado, o seu uso em sistemas de criação de peixes. PALAVRAS-CHAVE: Eichhornia crassipes, fósforo, amônia, qualidade de água Biofilter efficiency of water hyacinth on limnological variables in irrigation channels used for tambaqui farming ABSTRACTThe use of biofilter of aquatics plants can be an alternative for the treatment and minimization of effluents generated in fish farming. The objective of this work was to evaluate the effect of water hyacinth (Eichhornia crassipes) in the improvement of the limnological variables of water of supply channels used for fish farming. The experiment was conducted in supply channels over a period of 60-days at sampling intervals of fifteen days. The channels were sectioned with screens. A density of 120 fish m -³was used. The sections were divided into stages, alternating with presence or absence of water hyacinth. It was not observed significant differences in the level of ammonia (p >0.05), alkalinity and hardness of the effluent in both treatment systems. However it was observed that water hyacinth was efficient in the removal of nutrients such as, phosphorus (first weeks of cultivation). The use of water hyacinth can be recommended in fish farming systems.

Seasonal performance of aquatic macrophytes in improving physicochemical parameters of swine wastewater

“…In the winter, there was an increase of DMB equivalent to 159.3% for E. crassipes (Figure 8), due to the uptake of nutrients available in the SW by the plants, as quoted by Gentelini et al (2008). However, the production of biomass was higher in spring (2.2 times for E. crassipes, and for P. stratiotes, and 1.9 times for S. auriculata), since the temperatures were higher, confirming the statement of Silva et al (2014).…”

“…The results show that, in this warmer period, the DO levels in systems with macrophytes were always below 6.0 mg L -1 (Figure 3a), what can be explained by the non-occurance of movement of the wastewater in the treatment boxes, which can be characterized as a lentic environment. In lotic systems, where there is constant renewal and movement of the water in the channels, with flow above 4000 L h -1 , the gas exchanges between the aquatic environment and the atmospheric oxygen are boosted, allowing the achievement of DO levels above 6.0 mg L -1 (Silva et al, 2014). Thereby, the absence of agitation of the wastewater may have compromised the DO levels in the treated wastewater.…”

“…In the winter, the production of DMB was lower, for the three species (E. crassipes, P. stratiotes and s. auriculata), when compared to the production obtained in the spring. According to Silva et al (2014), the increase in the temperature can positively influence the increase in the biomass. Supporting this hypothesis, Gentelini et al (2008), using E. crassipes in the wastewater treatment of organic fish farming at a temperature of 18.7 °C, obtained an average production of 8.03 kg m -2 , which was lower than the one found by Silva et al (2014), which, using E. crassipes in the treatment of fish farming wastewater, at a temperature between 27.9 and 29.2 °C, reached a production of 21.64 kg m -2 .…”

Volatilization of ammonia in systems of treatment of swine manure with aquatic macrophytes

“…For Henry- Silva and Camargo (2000b), the highest pH found only in the effluent is probably related to the photosynthesis of the phytoplankton present in the site, which, by assimilating the CO 2 available in the water, increases the pH values of the medium. Silva et al (2014) found out that the effluent from water supply channels with tambaqui farming treated with Eichhornia crassipes (Mart.) Solms showed lower pH values when compared to the treatments without plants.…”

Atributos Químicos De Resíduos Orgânicos Compostados

“…Semelhante ao Ca, os compostos que utilizaram dejetos de suínos e bovinos (DBB, DBE e DSE) e plantas de aguapé (ALA) apresentaram maiores teores de Mg. Loureiro et al (2007) observaram durante análise do processo de compostagem que a utilização de dejetos de bovinos influencia positivamente no teor de Mg do composto. Com o uso de ALA, os maiores teores Mg podem ser atribuído a alta capacidade de extração do nutriente pelas plantas de aguapé em lagoa de estabilização de efluentes de abatedouro de frangos (SILVA et al, 2014).…”