BEHAVIOR OF NITROGEN AT DEPTH IN THE CERRADO AND AMAZON BIOMES DUE TO INTENSIFICATION OF LAND USE.

• Grant number: 22/16610-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2023
• End date: March 31, 2024
• Field of knowledge: Agronomical Sciences - Agronomy - Soil Science
• Principal Investigator: Carlos Eduardo Pellegrino Cerri
• Grantee: Leonam Yoshihiro Ishii
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

Nitrogen is an essential nutrient for life. Its cycle has undergone major changes over time due to the introduction of nitrogen fertilizers in agriculture. In the case of Brazil, in particular the state of Mato Grosso, the process of intensification of agricultural production and the change in land use stand out, reflecting an increase in the consumption of nitrogen fertilizers and replacement of the natural vegetation of the Amazon and Cerrado biomes in productive areas. For this reason, we propose a study to quantify inorganic N (ammonium and nitrate) in two farms in the state of Mato Grosso, Itamarati and Tanguro, inserted in the Cerrado and Amazon biomes, and under different uses - native vegetation, monoculture soy and cotton and Soy. Deformed and undisturbed soil samples will be collected at four random points per use, initially every 10 cm up to 50 cm, then every 50 cm up to 200 cm, and every 100 cm up to 400 cm. The deformed samples will be used to determine soil texture, pH, H+Al, available phosphorus, potassium, calcium and magnesium. Total soil carbon and nitrogen will be determined in an elemental analyzer. Soil inorganic nitrogen will be extracted in 2 mol potassium chloride solution and quantification will occur by the colorimetric method. Soil density will be determined by the dry mass of soil by the volume of the ring (undisturbed samples). Analysis of variance will be performed after checking the normality of the results (Shapiro-Wilk test - p < 0.05); in case of significant F values (p < 0.05), means will be compared by Tukey's test (p < 0.05). This study has great environmental relevance, as it will bring information about the existence of inorganic nitrogen in depth and discuss the impact of the change in use and intensification of it on the soils of the Cerrado and Amazon.