Green Manure And Sewage Sludge Used To Recover The Fertility Of A Degraded Oxisol

For soil remediation is necessary an adequate management that provides the maintenance and enrichment of the soil organic matter, for that, one alternative is the use of green and organic manure combined with correct fertilization. The objective of this research was to evaluate the effect of green manure and sewage sludge in the recovery of the chemical attributes of an Oxisol. The research was installed in an Oxisol in which was taken out a layer of soil of 8.60 meters. The treatments were: area without management and with the soil exposure; area with natural vegetation of “Savannah†; only native tree Astronium fraxinifolium Schott; A. fraxinifolium+Canavalia ensiformis; A. fraxinifolium+Raphanus sativus; A. fraxinifolium+Brachiaria decumbens+60 t ha-1 of sewage sludge based on dry mass. Were evaluated the soil chemical characteristics to the layers 0.00–0.05; 0.05–0.10; 0.10–0.20 and 0.20–0.40 m. The soil presents high degree of chemical degradation but the sludge improve some chemical characteristics of the degraded soil, being possible reduce or, in some cases, exclude the use the mineral fertilizer. It is recommended the application of lime in the sludge to correct its pH, being possible use it without acidify the soil. The lime is significant to improve the soil chemical characteristics, while in the first year the green manure do not influence these