AGREGAÇÃO, GLOMALINA E CARBONO ORGÂNICO NA CHAPADA DO ARARIPE, CEARÁ, BRASIL

Abstract

Several factors are involved in the formation of soil aggregates, specially chemical, physical and biological origin. The glomalin, a protein produced by arbuscular mycorrhizal fungi (AMF), is one of the substances associated with soil aggregation. The aim of this study was to quantify the levels of soil organic carbon and glomalin in different vegetation types in Caatinga biome in Araripe plateau - Ceará state, and verify the relationship with aggregate stability and seasonality. Soil samples were carried out in dry and rainy seasons, in three vegetation types (Brejo de altitude, Carrasco and Cerradão) in Araripe National Forest to determine the water stability aggregate, soil total carbon, particulate carbon and glomalin. Seasonality effect was observed in the levels of easily extractable glomalin, suggesting that this fraction of glomalin is more sensitive to seasonal variations. The highest correlations were observed between the variables soil carbon and both fractions of glomalin, indicating that the protein produced by AMF is directly related to the amount of carbon, in addition to being an important component in soil aggregation of the Araripe.