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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Biomassa carbonizada como condiciondor de solo: aspectos agronômicos e ambientais do seu uso em solos de cerrado / Biochar as soil amendment: agronomic and environmental aspects of its application in soils of the Brazilian savana (cerrado)

PETTER, Fabiano André 02 July 2010 (has links)
Made available in DSpace on 2014-07-29T14:52:05Z (GMT). No. of bitstreams: 1 FABIANO ANDRE PETTER.pdf: 2453719 bytes, checksum: da5399318ecc7cdd53eb39e42af320d6 (MD5) Previous issue date: 2010-07-02 / The effect of biochar on the chemical and biological soil properties, on the physiological response and productivity of soybean and upland Rice and on N2O emission was investigated. The study was carried out in Nova Xavantina, Mato Grosso state between September 2006 and May 2009 on two different soil types: Haplic Ferralsol (soybean) and Dystric Cambisol (rice). The experimental design was a combination of strips and random blocks where 5 doses (0 kg ha-1, 100 kg ha-1, 200 kg ha-1, 300 kg ha-1 e 400 kg ha-1) of NPK (0-20-20) were distributed in strips and 5 doses of biochar (0 Mg ha-1, 2 Mg ha-1, 4 Mg ha-1, 8 Mg ha-1 e 16 Mg ha-1) in random a manner in the case of soybean and 4 doses (0 kg ha-1, 100 kg ha-1, 200 kg ha-1 and 300 kg ha-1) of NPK (05-25-15) were distributed in strips and 4 doses of biochar (0 Mg ha-1, 8 Mg ha-1, 16 Mg ha-1 and 32 Mg ha-1) in random a manner in the case of rice. For rice urea was applied as top dressing corresponding the NPK doses: 0 kg ha-1, 15 kg ha-1, 32 kg ha-1 e 50 kg ha-1 de N, respectively. Every treatment had 4 replications. The biochar was applied only once, before the instalation of the experiments to the 0-15 cm soil layer. Soil fertility parameters were evaluated in samples collected at 0-10 cm, 10-20 cm and 20-30 cm and pH, Ca, Mg, Al, H+Al, P, K, Cu, Zn, Fe, Mn, SOM and total C and N were measured. Among physiological parameters the height and dry mass of plants were evaluated plus the nutrient levels in plant tissue at flowering and yield. The evaluation of soil biological parameters included the basal respiration rate of the soil (C-CO2) and the microbial biomass carbon (MBC). Nitrous oxide (N2O) emissions were also measured. Total C was significantly higher at 0-10 cm in the 1st year after biochar application and at 10-20 cm in the 3rd year in the treatment with 16 Mg ha-1 biochar. There was interaction between biochar and NPK, resulting in increase in K levels at 0-10 cm, 1st and 3rd year after application of biochar and decrease in exchangeable acidity in the 1st year. The 8 Mg ha-1 and 16 Mg ha-1 biochar doses resulted in higher values of plant height and dry mass both in the 1st and 3rd year, however, biochar had no effect on nutrient levels in plant tissue. Soybean yields were, again, significantly affected by biochar doses in a positive and quadratic manner both in the 1st and 3rd year. There was a significant increase in P, Ca, levels and pH, and Al and exchangeable acidity (H+Al) were reduced at 0-10 cm in the treatments with 32 Mg ha-1 biochar. Similar effect was observed for (H+Al) and K at 10-20 cm. Biochar had no effect on other soil chemical parameters. It negatively affected the dry mass of the plants at 25 and 55 DAP, however, did not have influence on plant height. Rice yield was directly and linearly influenced by biochar doses. Increase in nutrient use efficiency (N, P, K) was also observed at the highest biochar dose (32 Mg ha-1). Biochar had no effect on C-CO2 and MBC but seu uso resulted in higher emission rates of N2O at the 32 Mg ha-1 dose. In conclusion, in general, biochar had similar effects on soil chemical properties and yields, however its effect was manifested in a greater manner (larger contrast) in the more sandy soil. It increased nutrient use efficiency. As of plant height and dry mass, soybean gave better response for biochar application than rice. Finally, biochar seems to maintain its effect on yield and increases its effect on SOM accumulation over time. / Estudou-se o efeito do carbono pirogênico nas características químicas e biológicas do solo, na fisiologia e produtividade das culturas da soja e do arroz de terras altas e na emissão de N2O para a atmosfera. Os experimentos foram realizados em Nova Xavantina, MT, em dois diferentes tipos solos: Latossolo Vermelho Amarelo (soja) e Cambissolo Háplico (arroz) em delineamento experimental com junção de faixas e blocos ao acaso, em que 5 doses (0 kg ha-1, 100 kg ha-1, 200 kg ha-1, 300 kg ha-1 e 400 kg ha-1) de NPK (0-20-20) e 5 doses de carvão vegetal (0 Mg ha-1, 2 Mg ha-1, 4 Mg ha-1, 8 Mg ha-1 e 16 Mg ha-1), no caso da soja, e 4 doses (0 kg ha-1, 100 kg ha-1, 200 kg ha-1 e 300 kg ha-1) de NPK (05-25-15) e 4 doses de carvão (0 Mg ha-1, 8 Mg ha-1, 16 Mg ha-1 e 32 Mg ha-1), no caso do arroz, foram aplicadas, para o carvão ao acaso, em 4 repetições (blocos). Combinado com NPK na cultura do arroz foi realizada aplicação de 0, 15, 32 e 50 kg ha-1 de N em cobertura, respectivamente. Para avaliação de fertilidade do solo foram coletadas amostras de solo nas camadas de 0-10 cm, 10-20 cm e 20-30 cm e analisados os seguintes atributos: pH, Ca, Mg, Al, H+Al, P, K, Cu, Zn, Fe, Mn, M.O., C orgânico e N total. Os parâmetros fisiológicos avaliados foram: altura, matéria seca, teor foliar dos nutrientes P, K, Ca e Mg, Fe, Cu, Zn e Mn em pleno florescimento e produtividade. A avaliação dos parâmetros biológicos do solo consistiu na determinação da taxa de respiração basal do solo (C-CO2) e carbono da biomassa microbiana (CBM). Foi avaliado a emissão de N2O para a atmosfera. Na cultura da soja houve aumento significativo nos teores de C total de 0-10 cm no 1° ano e 10-20 cm no 3° ano com a aplicação de 16 Mg ha-1de carvão. Verificou-se efeito na interação carvão e NPK, com aumento de K e na camada de 0-10 cm no 1° e 3° ano e acidez potencial apenas no 1° ano. As doses de 8 Mg ha-1 e 16 Mg ha-1 proporcionaram maiores alturas e massa seca nas épocas avaliadas. Não se verificou efeito nos teores foliares de nutrientes. A produtividade foi significativamente aumentada em razão da aplicação de 16 Mg ha-1. Na cultura do arroz houve aumento significativo nos teores de P e Ca e no pH e redução de Al e H+Al na camada de 0-10 cm com a aplicação de 32 Mg ha-1de carvão. Esse efeito se repetiu para H+Al na camada de 10-20 cm e com aumento nos teores de K. Verificou-se efeito negativo do carvão na matéria seca aos 25 e 55 DAP, todavia não influenciou a altura das plantas. A produtividade foi aumentada à medida que se aumentou as doses de carvão. Observou-se maior eficiência no uso do N, P e K na dose de 32 Mg ha-1. Não se verificou efeito significativo do carvão no C-CO2 e CBM. Observou-se os maiores fluxos de N2O para a atmosfera na presença de 32 Mg ha-1. Como conclusão geral, o carvão vegetal teve efeito similar nas propriedades de fertilidade do solo e produtividade das plantas nos dois experimentos, entretanto seu efeito foi mais fortemente manifestado (maior contraste) no solo mais arenoso. Aumentou ainda a eficiência de uso de nutrientes. Considerando a altura das plantas e a massa seca a soja apresentou melhor resposta para a aplicação de carvão no solo. Finalmente, o carvão vegetal manteve seu efeito na produtividade e aumentou a acumulação da M.O. no solo com o passar do tempo.

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