Acúmulo de carbono e nutrientes em resíduos culturais de abacaxizeiro fertirrigado com esgoto sanitário tratado

Abstract

The agricultural use of wastewater is considered a viable alternative for food production, and can reduce production costs of pineapple, by partially replacing irrigation and nutritional demand of plants. Such management may increase the production and storage of plant residues and nutrients in the soil for subsequent crops. The objective of this study was to evaluate the effect of different doses of the reference element (Na), from sanitary sewage, after tertiary treatment (EST) in TEE-Janaúba, on the storage of dry matter, carbon and nutrients in different cultural remains cultivars of pineapple. The study was delineated in a randomized complete block design with four replications in the subdivided plots scheme, with five treatments related to the EST doses and three plots of the pineapple cultivars: Pérola, Smooth Cayenne and IAC Fantástico. The EST doses were calculated based on the annual maximum limit of Na supplied to the soil, corresponding to 150 kg ha-1, applying 0%; 100%; 200%; 300% and 400% of this limit. The doses of EST do not interfere in the accumulation of dry matter and the contents and accumulation of organic carbon, macronutrients and sodium of the cultural remains of the pineapple. The cultivar Pérola has lower accumulation of dry matter and carbon in relation to cultivars IAC Fantástico and Smooth Cayenne. The accumulation of macronutrients in the cultural remains of the cultivars IAC Fantástico, Pérola and Smooth Cayenne, shows the following decreasing order: N> K> Ca> Mg> S> P.