Cultivo do jambu em canteiros com compostagens laminares realizadas com resíduos orgânicos disponíveis na Amazônia Oriental

Abstract

Jambu is one of the principal vegetables in the Northern region of Brazil and its cultivation in an organic system requires the use of fertilizers that can be obtained through the use of locally available residues. Laminar composting stands out as an alternative to process this waste in order to adapt it for its agricola use, because it is a low cost process and keeps the soil covered. The general objective of this work was to realize a case study in a family production unit, in order to prove the viability of the laminar composting of locally available residues aiming at obtaining fertilizers destined to an organic production system of jambu. The study was realized in a family production unit-UPF, located in the municipality of Igarapé Açu, state of Pará. The laminar compound was constituted by the mixture of chicken feather, ash and açaí core, being evaluated several characteristics at zero, 30, 60 and 120 days of composting, such as: pH, electrical conductivity, C, N, P, K, Ca, Mg contents, C: N ratio, potential CO2 and NH3 emissions. Beyond the characteristics of the compost, soil fertility analyzes were also performed on the parcels that received the compost. The jambu production experiment evaluated the effect of different composting times, being zero, 30, 60 and 120 days before transplanting the jambu seedlings, in addition to a control treatment without laminar composting. The harvest of the jambu was realized 60 days after the planting of the seedlings, evaluating the development of the vegetable through the characteristics fresh weight of the plants, number of flowers and length of the root. Most of the characteristics evaluated in the compost and in the soil showed highly significant effects as a function of lamiar composting time, with the exception of the characteristics of C and P for the laminar compost and N and of P for the soil, but whose effects showed levels of significance close to 6.0%. It was at zero time of laminar composting when it was observed that the soil had the best conditions for the development of jambu, with higher pH, lower Al content and higher nutrient contents, such as N, Mg and K. The weight of the plants, the number of flowers and the length of the root of the jambu plants were highly significant, and the best answers were observed at zero time of laminar composting. These results prove the agronomic feasibility of the laminar composting of organic waste in the use of organic jambu production systems.