Effect of nitrogen fertilizer sources and precipitation on ammonia volatilization in pastures

• Grant number: 24/16909-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2024
• End date: October 31, 2025
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Pastures and Forage Crops
• Principal Investigator: Ricardo Andrade Reis
• Grantee: Eduardo Borazo Bolsoni
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil

Abstract

The search for strategies that increase the quality and productivity of pastures in Brazil, being developed extensively, and still collaborate with the mitigation of climate change is crucial, highlighting the use of nitrogen fertilizers. However, the inadequate application of these fertilizers can result in ammonia (NH¿) volatilization, especially in periods of low precipitation, which corresponds to part of the N lost in the systems and released into the atmosphere in the form of NH¿. This study aims to evaluate nitrogen losses in the form of ammonia from different sources of nitrogen fertilizers associated with precipitation. The evaluations will be conducted in three periods of 21 days, in the Forage sector of the Faculty of Agricultural and Veterinary Sciences, UNESP, Jaboticabal Campus, in an area of ¿¿Urochloa brizantha cv. Marandu, during the rainy season from 12/2024 to 04/2025. The study will be conducted according to a randomized block design to evaluate four sources: 1 - control; 2 - urea fertilization; 3 - ammonium sulfate fertilization; 4 - ammonium nitrate fertilization, and 3 precipitation scenarios: 1 - 0 mm, 2 - 10 mm, 3 - 20 mm, with 4 replicates per treatment and with collections on the 1st, 3rd, 5th, 9th, 14th and 21st day after treatment application (The fertilizer plots will be applied together with the precipitation simulations, once per period), using semi-open chambers to quantify NH¿ volatilization. After evaluating the nitrogen content of the samples by distillation and titration method and the climatic variables, the results will be analyzed with the R software, and the data will be published in scientific events and articles.