Nitrogen balance in sugarcane due to different application forms of nitrogen in the crop and losses by N2O emissions, leaching and runoff

• Grant number: 17/13619-0
• Support type: Program for Research on Bioenergy (BIOEN) - Regular Program Grants
• Duration: February 01, 2018 - January 31, 2020
• Field of knowledge: Agronomical Sciences - Agronomy - Soil Science
• Principal researcher: Sérgio Gustavo Quassi de Castro
• Grantee: Sérgio Gustavo Quassi de Castro
• Home Institution: Centro Nacional de Pesquisa em Energia e Materiais (CNPEM). Ministério da Ciência, Tecnologia e Inovações (Brasil). Campinas , SP, Brazil
• Assoc. researchers: Henrique Coutinho Junqueira Franco ; João Luís Nunes Carvalho ; Oriel Tiago Kolln

Abstract

Low nitrogen (N) efficiency is a substantial worldwide concern that threatens the sustainability of sugarcane production, due to the environmental impacts of N2O emissions from fertilization, whose global warming potential is relatively higher than other greenhouse gases (CH4, CO2). The nitrogen use efficiency (NUE) associated with the management practices of fertilization represents a viable alternative of adoption for the mitigation of environmental impacts due to N losses in the soil-plant-atmosphere. The increase of nitrogen use efficiency (NUE) associated with fertilization management practices shows potential because approximately 50% of N-fertilizer applied in sugarcane crop is recovered by soil and plant fractions; the losses by runnoff are unknow in sugarcane fields around the world; N2O emissions could be reduced by N-fertilizer application incorporated, but in other hand this application methods could increase the losses by leaching. In this context, the present project aims to quantify the losses by runoff, leaching, N2O emissions and the NUE of sugarcane when applied N-fertilizer in sugarcane ratoon according to fertilization method. The experimental design will be randomized blocks with three replications and three treatments: 1- surface application of N-fertilizer above the green cane trash blanket in sugarcane row; 2- N-fertilizer application incorporated at 0.08m depth on both sides of sugarcane row; 3- control treatment - without N fertilizer. During the sugarcane crop cycle, the following parameters were evaluated: N2O emissions, nitrate leaching, losses by runoff and NUE by the crop according to N-fertilizer application forms. The main contribution of this project is evaluating whether the N-fertilizer application forms influence N losses in the soil-plant-atmosphere system. Therefore, it is possible know the best method to apply N-fertilizer to mitigate of these N-losses, increase the NUE by crop, as well as do the nitrogen balance in sugarcane crop. (AU)