Mineralização do nitrogênio dos resíduos vegetais adicionados aos solos ácidos

Abstract

The amount of organic matter in the soil (MOS) is one of the main indicatives of soil quality. It is understood as organic matter (OM) being all the vegetal residue, manure of animals and microorganisms in different states of decomposition, making that its addition in the soil like fodder between plantations supra the need of nutrients of the ground. Therefore, the objective of the work is to evaluate the chemical changes by the addition of vegetal residues in the soil of the western region of Londrina-PR. The study will be conducted at the Instituto Agronômico do Paraná using a dystroferric RED LATOSOL with pH 4.3 (forest soil) and pH 6.3 (cultivated soil), collected in the 0-20 cm layer. Mucuna cinereum shall be used as plant residues; Canavalia brasilienses and post harvest corn straw, incubated at 2 kg soil at different pH values using the proportions 1.0%, 2.0% and 5.0% (m / m). Each experiment will be done in triplicate and will last 7 months, with periodic collections during the period. The concentrations of carbon by the method of Walkley Black and nitrate and ammonium by the colorimetric method will be determined in the soil samples. The results indicate that the residue of corn straw is not feasible for nitrogen supply in the soil due to its composition that leads it to compete for nitrogen with the soil microorganisms. The residues of Canavalia brasiliensis and Mucuna cinereum had similar behaviors being two residues indicated for the forage of the soil and nitrogen supply to the environment.