Chemical Characteristics of Soil and of the Earthworm Casts in Commercial Plantation of Eucalyptus grandis

Abstract

The chemical characteristics of earthworm casts and a soil sample from a commercial plantation of Eucalyptus grandis aged 3 years old near the city of Mogi-Guaçu in the State of São Paulo, Brazil, were compared. The casts were collected at the surface of the mineral soil, while the soil was collected at depths of 0 - 5; 5 - 10; 10 - 20 and 20 - 30 cm. The Ca⁺² and Mg⁺² contents of casts, in comparison to the 0 to 5 cm soil depth, were 11 times higher,while the K⁺ contents were 3 times higher. In addition, the cation exchange capacity (CEC) and C contents were 4.41 and 2.83 more concentrated in the casts, respectively. It was observed a decrease in Aluminum saturation (m%) from 73%, in the depth of the 0-5 cm, to 45% in the casts. While the chemical characteristics of the native earthworm casts represent a distinct improvement over the soil, it remains to be seen what influence, if any, this has on the growth and nutrition of E. grandis.