Aplicação De Escória Siderúrgica, Calcário E Ureia Em Latossolo Cultivado Com Arroz

Abstract

No Brasil, são produzidas cerca de 6,25 milhões de toneladas de escórias de siderurgia (Medeiros et al. 2009), como subproduto da mineração do ferro e da produção do aço, consideradas as fontes mais abundantes e baratas de silicatos. Assim, os materiais inertes do minério de ferro e do carvão, que não foram reduzidos no processo siderúrgico de formação do aço, combinam-se com o cálcio (ca) e o magnésio (Mg) do calcário, dando origem à es- ABSTRACT RESUMOcória de siderurgia (Pereira 1978). este subproduto é rico em constituinte neutralizante (Sio 3 2-), capaz de diminuir a acidez dos solos tropicais altamente intemperizados, com caráter ácido, e fornecer ele-

Attributes of the soil fertilized with sewage sludge and calcium and magnesium silicate

“…Unlike the results of this study, Prates et al (2011) observed increase in sum of bases and reduction in potential acidity with the application of Ca-Mg silicate on the soil. Corroborating these results, Vidal & Prado (2011) also observed that the application of slag in a Latosol cultivated with rice promoted increase in sum of bases and reduction in potential acidity. The values of potential acidity in the layers of up to 10 and > 10 cm were agronomically classified as Low and Medium, respectively, and the values for sum of bases in the layers of up to 20 and > 20 cm were classified as Very good and Good, respectively, according to Alvarez V. et al (1999).…”

“…However, there was an increase in pH compared with the initial soil condition (Table 1) and the results were agronomically classified as High, according to Alvarez V. et al (1999). Although not observed in this study, increases in soil pH with the application of Ca-Mg silicates have been widely reported in the literature (Barbosa et al, 2008;Faria et al, 2008;Korndörfer et al, 2010;Prates et al, 2011;Vidal & Prado, 2011). Table 2.…”

“…Different results were obtained by Vidal & Prado (2011), who observed that the application of slag promoted increase in CEC and reduction of soil potential acidity. CEC (t) values in the layers up to 20 and > 20 cm can be agronomically classified as Very good and Good, respectively, while CEC (T) values in the layer up to 40 cm are classified as Good.…”

“…The use of Mg silicates in agriculture promotes various agronomic benefits, among which the reduction of phosphorus (P), increasing its availability to plants (Korndörfer, 2002), and improvements on soil chemical properties, through the increase of pH, sum of bases (SB), cation exchange capacity (CEC), base saturation (V%) and potential acidity (H+Al) (Prates et al, 2011;Vidal & Prado, 2011). In addition, the deposition of silicon on cell walls can increase plant resistance to lodging and create physical barriers to the development of diseases and to the attack of chewing pests (Korndörfer, 2002;Marchezan et al, 2004).…”

“…As an alternative for the use of limestone to correct soil acidity, calcium (Ca) and magnesium (Mg) silicates have been used to neutralize soil acidity and provide Ca, Mg and silicon (Si) to plants (Chaves & Farias, 2008;Faria et al, 2008;Vidal & Prado, 2011).…”