Soil chemical attributes and heavy metals and sugarcane leaves with silicate application
Abstract
This study aimed to evaluate the effect of different silicate rates and sources on soil chemical properties and soil contamination with heavy metals at different depths (0-15 cm, 15-30 cm and 30-45 cm). Also sugarcane leave micronutrient contents and heavy metals. The experiment was conducted on the Vargem farm, which belongs to Guaira Sugar Mill, Guaira, São Paulo, Brazil. The adopted experimental design was randomized blocks with four replications. The treatments had a factorial design 2 x 3 + 1, with two silicates (Holcim® and Agrosilício®) and three silicate rates (400, 800 and 1600 kg ha-1). The control treatment (control) had no silicate application. The RB92-5345 variety of sugarcane was planted on May 1, 2008. Foliar samples were taken at harvest and soil samples (depths: 0-15, 15-30 and 30-45 cm) were taken after harvest. The following chemical attributes were assessed: pH, CaCl2, Al3+, Ca2+, Mg2+, micronutrients: Fe, Zn, Mn, Cu, Si, and heavy metals: Cd, Cr, Ni and Pb. The use of industrial waste in the culture of sugar cane improved soil quality, providing plants with adequate nutrients levels. To use this as an alternative nutrient source does not promote contamination of soil at deeper depths. The Agrosilício® and Holcim® silicates increased pH when rates were larger. The Agrosilício® silicate increased soil Si content in the 0-15 cm soil ayer and Mn content at the 15-30 cm soil layer. The application of silicates did not cause soil contamination and sugarcane leaves were not contaminated with heavy metals.
