Recuperação da estrutura de um Latossolo vermelho degradado utilizando lodo de esgoto

Abstract

The aim of this study was to investigate the influence of sewage in the recovery of the structure of a degraded Red Latosol (Oxisol) being cultivated for 4 years with eucalyptus (Eucalyptus citriodora) and (Brachiaria decumbens) in Selvíria, MS, Brazil. We used a randomized block design with 6 treatments and 4 replications. The treatments were: control (without the use of sewage sludge and mineral fertilizers); mineral fertilizer, 30 t ha^-1 of sewage sludge; 60 t ha^-1 of sewage sludge, todos with soil cultivated with eucalyptus and pasture, and two witnesses: savannah vegetation and exposed soil. In 2007, we evaluated physical soil properties: the distribution of pore size, soil bulk density, distribution of soil aggregate stability and water; and chemical soil properties: phosphorus, potassium, calcium, magnesium, organic matter; potential acidity( pH), sum of bases, cation exchange capacity and base saturation, in depths: 0.00 to 0.05, 0.05-0.10, 0.10 -0.20 and 0.20-0.40 m; resistance to moisture penetration and gravity, in depths: 0.00 to 0.15, 0.15 to 0.30 and from 0.30 to 0.45 m. It is concluded that the sewage sludge yielded positive changes in soil structure and recovery of soil chemical properties.