Fosfato monoamônico com tecnologia associada: umidade, temperatura, época de aplicação e tempo de contato

• Autor(a) principal: Siman, Felipe Cunha
• Data de Publicação: 2023
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/16769
• topic: Agronomia; Polímero; Biochar; MAP; Torta de filtro; Fertilizante; Fósforo; subject.br-rjbn

The predominance of soils with a marked degree of weathering and high levels of Fe and Al oxides result in low nutrient availability and high phosphorus (P) adsorption capacity. In these soils, soil-plant competition for P added via fertilization is high, which reduces efficiency, as well as the residual effect for successive crops. In this context, the use of fertilizers with associated technology can be an alternative to reduce the intensity of P adsorption and increase availability to plants, increasing absorption and subsequent crop response. The objective of this work was to evaluate the dynamics of P from the application of phosphate fertilizers with associated technology. In the first chapter, the aim was to characterize the conventional phosphate source and associated technologies, identifying the thermogravimetric behavior, the main crystalline phases occurring in fertilizers and the P and C content. The second chapter aimed to evaluate the P levels in the soil over time from the application of phosphate fertilizers with associated technology under temperature variation, different volumetric soil water contents and over the evaluation periods. With this experiment, it was concluded that fertilizers with associated technology altered the availability of P compared to the conventional source in lower volumetric water content (60 % CC) and can be used in combination to supply crop demand in the short and long term. The third chapter aimed to evaluate the P content in the soil extracted by water and Mehlich-1, dry matter mass of the aerial part and leaf area in the corn crop after incubation of the soil with phosphate sources with associated technology over 150 days and by two successive cultivations. As a result, it was observed that fertilizers with associated technology were superior to the soluble source for the P content in water and Mehlich-1 and for the initial development of the corn crop in the second cropping cycle. Chapter 4 was an experiment conduced in a greenhouse and aimed to evaluate the initial development of the coffee tree from the use of a conventional phosphate source (monoammonium phosphate) and with associated technologies applied in clayey soil with three volumetric water contents. The results indicated that the highest efficiency of the associated technologies occurred in the lowest volumetric water contents, in general 60 and 70 % of the field capacity (CC), evidencing its efficiency for water stress conditions or low water content in the soil. Chapter 5 aimed to evaluate the initial development of the corn crop under the application of a conventional phosphate source associated with the use of technologies subjected to three volumetric water contents and in three successive crops. In general, it was observed that the coated fertilizers were more efficient compared to the conventional source for all variables and in the three crop cycles and at lower volumetric water contents, which indicates potential use in field conditions for crops not irrigated. Finally, chapter 6 aimed to evaluate the effects of phosphate fertilizers with associated technology and the availability of phosphorus in the soil after successive coffee crops. It was concluded that the main effect of fertilizers with associated technology occurred in the labile fraction of the soil, but an increase in P levels was also observed in the moderately labile and restricted labile fractions.