Resíduos de açaí, seus efeitos na emergência de plântulas e produção de mudas em meio aquapônico.

Abstract

Aquaponics can be a sustainable alternative to conventional agriculture, as it is a way of producing food that works in an integrated way, which combines the creation of aquaculture animals with the cultivation of vegetables without the use of soil, or hydroponics. However, basic information on cultivation for many Amazonian species is still lacking, as is the use of products or by-products from the region in aquaponic systems. In systems based on the media technique, substrate is used in the hydroponic reservoir, but the choice depends on biological, chemical and physical factors of the material that can affect production. In this context, this work aims to verify the use of açaí residue as a substrate for biofiltration and seedling production in an aquaponic system. The experiment was carried out in a completely randomized design, with four treatments and three replications, verifying the effect of continuous water flow through the açaí seed, in three different water levels (5, 10 and 15 cm) and a control (without addition of of açaí residue). During 30 days, water quality, zootechnical and phytotechnical performance were analyzed. Over 28 days, total ammonia was less than 1 mg L-1 in the açaí treatments and greater than 5 mg L-1 in the control, while there was no significant difference between groups (p>0.05) for nitrite. and phosphate. Dissolved oxygen, total dissolved solids and conductivity were low, while pH and alkalinity increased. The surface germination of açaí, after 22 days, was 2.63 and 3.07 times higher in the water level of 10 cm, although the highest seedling growth was observed in the treatment with a level of 5 cm. Regarding the zootechnical performance of tambaqui, after 30 days, no significant differences were observed between the groups. Therefore, the açaí residue is able to efficiently remove nitrogen compounds, not negatively affecting tambaqui growth.