Sewage Sludge Application in Eucalyptus urograndis Plantation: Availability of Phosphorus in Soil and Wood Production

• Published in: Frontiers in environmental science Vol. 8
• Main Authors: Abreu-Junior, Cassio Hamilton, Oliveira, Marcelo Gomes de, Cardoso, Paulo Henrique Silveira, Mandu, Thays da Silva, Florentino, Antonio Leite, Oliveira, Fernando Carvalho, Reis, Josimar Vieira dos, Alvares, Clayton Alcarde, Stape, José Luiz, Nogueira, Thiago Assis Rodrigues, Capra, Gian Franco, He, Zhenli
• Format: Journal Article
• Language: English
• Published: Lausanne Frontiers Research Foundation 28.07.2020; Frontiers Media S.A
• Subjects: Agriculture; alternative fertilizers; Availability; Biomass; biosolids; Dosage; Environmental science; Eucalyptus; Experiments; Fertilization; Fertilizers; Hardwoods; Hydroxyapatite; Microorganisms; Mineral fertilizers; Nitrogen; organic fertilizer; Organic matter; P fractionation; Phosphorus; Plantations; Sedimentation & deposition; Sewage sludge; Sludge; soil P lability; Soils; Water treatment; Wood; Brazil
• ISSN: 2296-665X; 2296-665X
• DOI: 10.3389/fenvs.2020.00116

Phosphate fertilizers used in planted forests mainly come from scarce and non-renewable sources, and there is a need for new sources of phosphorus (P). An alternative is the use of sewage sludge (SS), rich in organic matter, nitrogen and P. The objectives were to evaluate the soil P availability and its effect on wood production in 22-months old Eucalyptus urograndis plantation treated with SS. A field experiment was set up in a randomized complete block design, four replicates, with the following treatments: control without fertilization; mineral fertilization (MF); 14.5 Mg ha-1 of SS + 22 kg ha-1 of P (S1P1); 29 Mg ha-1 of SS (S2); 29 Mg ha-1 of SS + 17.5 kg ha-1 of P (S2P2); and 43.5 Mg ha-1 of SS (S3), dry base. Of total P in SS, 65% was in organic form, and 42% was in labile + moderately labile forms. S2P2 and S3 positively altered the pattern of soil P distribution, with more P in the labile and moderately labile fractions than non-labile fraction, along 0-20 cm depths, than MF and control. There were higher microbial and available P as a function of SS dose. Wood volume and biomass were highly related to soil P availability as a function of SS dose. Within the SS treatments, S2P2 resulted in higher gains of volume and biomass of wood. The SS application at recommend rate, supplemented with 66% of recommended P fertilizer dose in Eucalyptus plantations, can reduce the use of P fertilizer by 33%, N fertilizer by 100% and maintain comparable soil P availability and wood production.