NÍVEIS CRÍTICOS DE ENXOFRE EM SOLOS DE PERNAMBUCO

Abstract

The burning of the sugar cane for occasion of the harvest causes an expressive volatilization of the sulfur contained in the vegetable material, worsening possible deficiencies of this nutritious the short and average term. The goal of this research was to evaluate and to determine the critical levels of sulfur in soils using the mineral gypsium as sulfur source. They were installed four field rehearsals in different class texturais soils. In all rehearsals the experimental delineation employee was blocks at random. The treatments in each rehearsal they constituted of the combination of five doses of mineral gypsium and three chemical extractors, with three repetitions. They evaluated the treatments at thirty days after the application of the sulfur doses in the depths 0-0,2m of sampling. The sulfur doses were defined from need to calagem, for the layer 0,4-0,6 m of depth. With the results of recovered sulfur and production of the sugar cane, they were certain the critical levels of sulfur in the soil. The ammonium acetate extractor in acetic acid extracted more sulfur in loamy soils, of low values of P-rem and with larger contents of organic matter, while the calcium chloride extractor introduced sulfur extraction smaller power, at the same terms. Already the calcium phosphate, contend match and in the presence of acetic acid, extracted efficiently, independent sulfur of physical and chemical characteristics of the soils. The critical levels of sulfur in the soil were increasing in loamy soils, of low values of P-rem and with larger contents of organic matter.