Search

Recently, biochar has shown to be an alternative to waste disposal and a source of nutrients, acting as a soil amendment. The effects of two types of biochar on soil properties and sugar beet production as well as potential for carbon (C) sequestration were evaluated: biochar produced from sewage sludge (SB) and biochar produced from a 1:1 mixture of sewage sludge and sugarcane bagasse (MB). A greenhouse pot experiment was conducted using a sandy loam soil from the Brazilian savanna under treatments of MB applications at 2.5%, 5.0%, 7.5%, and 10.0%, SB application at 5.0%, and a conventional fertilization (CF) using lime and mineral fertilizers, with no fertilization as a control. After incubation for 45 d, seedlings were transplanted into each pot and cultivated for 55 d. Biochar characterization showed that pyrolysis reduced the biomass volume drastically, but concentrated the trace elements per unit of biochar weight. The MB treatments increased soil total C (by 27.8%) and pH (by 0.6), reduced the concentrations of nutrients, except for potassium (K), and chromium (Cr), and did not significantly alter lead (Pb) and cadmium (Cd) concentrations. Results of stable isotopes showed that all biochar treatments increased the total soil C stock and stability, suggesting a potential for application in C sequestration, and improved overall soil fertility. However, the biochar treatments also increased the concentrations of trace elements in the soil and plants. The sugar beet yields at 10.0% MB and 5.0% SB corresponded to 55% and 29% of the yield obtained in the CF treatment, respectively. These results may be due to biochar nutrients not being bioavailable when required by plants or to biochar nutrient adsorption.

CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior The biomass pyrolysis process may be an alternative for the agricultural use of sewage sludge. This study aimed to evaluate the use of of biochars from mixture of sewage sludge and sugarcane bagasse (BB, 1:1 relationship sewage sludge and sugarcane bagasse) on sugar beet (Beta vulgaris L.) production and nutrition. A greenhouse experiment was conducted with five application rates of BB: 0, 2.5, 5, 7.5, and 10% (v/v), and two additional treatments, biochar from sewage sludge (BS, application rate 5% (v/v)) and conventional treatment (CV) that received lime and mineral fertilizer. The treated soils were incubated for 45 days, after which, seedlings were cultivated for 55 days. Biochar produce from sewage sludge and sugarcane bagasse is an alternative technology to reduce the potential for contamination of sewage sludge and to incorporate more stable carbon forms in the soil. Although, biochar has increased soil fertility, fine roots and nutrient uptake efficiency by sugar beet plants, total dry matter yield was significantly lower than that obtained in conventional treatment. O processo de pirólise da biomassa pode ser uma alternativa para o uso agrícola de lodo de esgoto. Este trabalho objetivou avaliar o uso de biochar produzido a partir da mistura de lodo de esgoto e bagaço de cana (BB, 1:1 relação lodo de esgoto e e bagaço de cana) na produção e nutrição de beterraba (Beta vulgaris L.). Conduziu-se um experimento em casa de vegetação com cinco dose de BB: 0, 2,5, 5, 7,5 e 10% v/v, e dois tratamentos adicionais, biochar de lodo de esgoto (BS, 5% v/v) e tratamento convencional (CV) com calagem e fertilizantes minerais. Após 45 dias de incubação dos solos tratados, cultivou-se as plantas por 55 dias. O biochar produzido a partir de lodo de esgoto e bagaço de cana-de-açúcar é uma tecnologia alternativa para reduzir o potencial de contaminação do lodo de esgoto e incorporar formas mais estáveis de carbono ao solo. Embora o biochar tenha aumentado à fertilidade do solo, as raízes finas e a eficiência de absorção de nutrientes pelas plantas de beterraba, a produção de matéria seca total foi significativamente menor que a obtida no tratamento convencional.

Os objetivos do estudo foram caracterizar biocarvões produzidos a partir de lodo de esgoto (BL) e da mistura de lodo de esgoto com bagaço de cana-de-açúcar (BBL) e avaliar seus efeitos nos atributos químicos do solo e na produção e nutrição mineral de plantas de beterraba. Os biocarvões foram produzidos por meio do processo de pirólise a 450º C. O experimento foi conduzido em casa de vegetação do ICA / UFMG de Julho a Outubro de 2015 em delineamento experimental inteiramente casualizado, com sete tratamentos e cinco repetições, que corresponderam a níveis crescentes de BBL: 0; 2,5; 5; 7,5 e 10% (volume / volume) e dois controles: adubação mineral (NPK) e dose intermediária de BL (5%). Todos os tratamentos com biocarvão tiveram adição de fosfato natural reativo Bayovar. O solo utilizado foi um Latossolo Vermelho Amarelo de baixa fertilidade natural. Inicialmente, o solo com os respectivos tratamentos com biocarvão e fosfato natural foram incubados por um período de 45 dias, em vasos de 4 dm-3 de capacidade. O mesmo procedimento foi adotado para o tratamento com adubação mineral, sendo o solo incubado apenas com corretivo da acidez do solo. Após a incubação, mudas de beterraba, produzidas em substrato comercial, foram transplantadas e cultivadas durante 55 dias. Amostragens de solo de cada vaso foram coletadas após os 45 dias de incubação e após os 55 dias de transplantio das mudas. Os biocarvões e solo foram analisados quanto aos teores de nutrientes, Cr, Cd e Pb, fracionamento físico da matéria orgânica e composição isotópica 13C. As plantas de beterraba foram divididas em: parte aérea, raízes tuberosas e raízes finas para a determinação da massa seca e dos teores de nutrientes, Cr, Cd e Pb. Os teores de nutrientes, Cd e Pb dos biocarvões ficaram abaixo dos limites estabelecidos pela legislação brasileira. A adição de bagaço de cana-de-açúcar ao lodo de esgoto aumentou o rendimento e qualidade do biocarvão. A aplicação de biocarvões teve efeito corretivo sobre os componentes da acidez do solo, aumentou a disponibilidade de nutrientes, de carbono orgânico do solo e alterou a composição isotópica do solo. A dose de BBL aumentou a massa seca das plantas de beterraba e favoreceu a produção de raízes finas. Os teores Fe, Mn, P, Mg nas plantas para todos os tratamentos ficaram acima de valores adequados de referência, porém não ocorreram sintomas de fitotoxidez. Por outro lado, os teores de Pb e Cd ficaram abaixo do limite de detecção. Dessa forma, o biocarvão teve influência positiva no melhoramento das propriedades químicas de solo e produtividade da beterraba, podendo ser considerado como um manejo adequado para os resíduos avaliados. The objectives of the study were to characterize biochars produced from sewage sludge (BSS) and sewage sludge mixed with sugarcane bagasse (BBSS) and to evaluate the effects on soil chemical properties and production and nutrition mineral of beets plants. The biochars were producing through pyrolysis process on 450º C. The experiment was conducted in greenhouse of the ICA / UFMG, from July to October 2015, in a completely randomized design, with seven treatments and five repetitions, corresponding to increasing levels of BBSS 0; 2.5; 5; 7.5 to 10% (volume / volume) and two controls: mineral fertilizer (NPK) and intermediate dose BL (5%). All the treatments with biochar had reactive phosphate "Bayovar" addition. The soil used was a Yellow Oxisol of low natural fertility. Initially, the soil with their respective treatments with biochar and natural phosphate were incubated for a period of 45 days in pots of 4 dm-3 capacity. The same process was adopted for treatment with mineral fertilizer, incubated only with corrective of soil acidity. After incubation, beet seedlings produced in commercial substrate were transplanted and cultured for 55 days. Soil samples were collected from each pot after 45 days of incubation and after 55 days of transplanting the seedlings. The biochars and soil were analyzed for nutrient content, Cr, Cd and Pb, physical fractionation of organic matter and 13C isotopic composition. Beets plants were divided into aerial part, tuberous roots and fine roots for the determination of dry matter and nutrient content, Cr, Cd and Pb. The nutrients contents, Cd and Pb of biochars were below the limits established by Brazilian legislation. The addition of sugarcane bagasse to sewage sludge increased the yield and quality of biochar. The application of biochars had corrective effect on the components of soil acidity, increased nutrient availability, soil organic carbon and change the isotopic composition of the soil. BBL doses increased the dry mass of beets plants and favored the production of fine roots. The contents of Fe, Mn, P, Mg in the plants for all treatments were above adequate reference values, but there was not symptoms of phytotoxicity. On the other hand, the Pb and Cd contents were below the detection limit. In this way, biochar had a positive effect in improving the chemical properties of soil and sugar beet productivity; it can be considered as proper waste management evaluated.