Fertilization using sewage sludge in unfertile tropical soils increased wood production in Eucalyptus plantations

Made available in DSpace on 2018-11-26T17:41:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-12-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Suzano Pulp and Paper Company S.A. Fertilization of Eucalyptus plantations using sewage sludge on unfertile tropical soils represents an alternative to using mineral N and P fertilizers. A 44-month field experiment was conducted to study the effects of increasing application of sludge, and its interactions with mineral N and P fertilizers, on wood volume. Four rates of sludge (0, 8,15 and 23 Mg ha(-1), dry base), N (0, 47, 95 and 142 kg ha(-1)) and P (0, 28, 56 and 84 kg ha(-1) of P2O5) were combined in a 4 x 4 x 4 factorial scheme in a totally randomized block design. Response surface and age-shift modeling was used to establish an initial recommendation for mineral fertilization of the Eucalyptus plantations treated with sludge and to analyze the implications of increased growth on the duration of the forest cycle in a tropical climate. The results showed that from 8 to 44 months after planting, the sludge application (with or without N and P) yielded a statistically larger wood volume (P < 0.05), compared to application of N and P fertilizers only. The response surface modeling showed the following outcomes: i) application of sludge based on N criterion reduced the need for N and P fertilizers by 100%; and ii) an increase in wood volume by 7% could be achieved, compared to NPK fertilizers only, if 2/3 of the recommended P was applied. The cultivation time to produce 150 m(3) ha(-1) of wood volume was 45 months for the control and was reduced by two, three, four, or five months, respectively, through application of recommended P, sludge dose, sludge plus one third of P, and sludge plus two thirds of P. On the whole, sewage sludge could represent an excellent unconventional N and P fertilizer source for wood production on unfertile tropical soils. (C) 2017 Elsevier Ltd. All rights reserved. Univ Sao Paulo, Dept Plant Nutr, Ctr Nucl Energy Agr, BR-13400970 Piracicaba, SP, Brazil Fed Univ Grande Dourados, Sch Engn, BR-79804070 Dourados, MS, Brazil EMBRAPA Cerrado, BR-73310970 Planaltina, DF, Brazil Univ Sao Paulo, Luiz de Queiroz Coll Agr, BR-13418900 Piracicaba, SP, Brazil Suzano Papel & Celulose SA, BR-18200000 Itapetininga, SP, Brazil Univ Florida, Inst Food & Agr Sci, Indian River Res & Educ Ctr, Ft Pierce, FL 34945 USA Sao Paulo State Univ, Sch Engn, Dept Plant Protect Rural Engn & Soils, BR-15385000 Ilha Solteira, SP, Brazil Univ Sassari, Dipartimento Architettura Design & Urbanist, Via Colombo 1, I-08100 Nuoro, Italy Univ Sassari, Desertificat Res Ctr, Viale Italia 39, I-07100 Sassari, Italy Sao Paulo State Univ, Sch Engn, Dept Plant Protect Rural Engn & Soils, BR-15385000 Ilha Solteira, SP, Brazil FAPESP: 2004/15097-0 FAPESP: 2015/09690-5 CNPq: 313374/2014-7