Utilização do rejeito da mineração do calcário laminado da Chapada do Araripe na correção da acidez do solo

Abstract

The extraction of limestone for ornamental purposes in the municipality of Nova Olinda, known as Pedra Cariri, has been causing a number of problems due a tmcontrolled generation and a inappropriate storage of the waste from the open pits in the location. In face of this problem, the main goal of the research paper is to evaluate a potential industrial application through a liming experiment using this mineral waste. The experiment lasted 3 months, between October 2015 and January 2016, and it was conducted by incubation of vases in greenhouse, containing doses varying among 0%, 50%, 100%, and 200% from the calculated recommended dosage, where the waste was applied in a acidic soil, with the aim of increasing the pH, correcting it. Also, in the experiment there was an application of a dose containing 100% from the recommended dosage of another type of limestone, in the same soil, a agricultura' calcitic lime, which is already industrialized and sold, used for comparing the efficiency between these two materials. Results of chemical analyses at the end of the experiment indicated that the powder from the mineral wasted was able to increase satisfactorily the soil pH, as well as reducing changeable acidity, potential acidity, and aluminum saturation. As agricultura' input, the powder from the mineral waste has shown a good efficacy because it increased the Calcium levels, an the sum between the changeable basis and the soil base saturation; however, there was not substantial increasing in K and Mg leveis. Between the two types of limestone used in 'the experiment, the efficacy was roughly the same; the only difference between them was the increasing in changeable Na in the soil caused by the powder from the Pedra Cariri waste in comparison to the other one.