CH4 and N2O Emissions in a Rice Field

First Measurements in the Uruguayan Productive System

  • Pilar Irrisarri Departamento de Biología Vegetal. Facultad de Agronomía. Universidad de la República. Garzón 809, CP 12900. Sayago. Montevideo, Uruguay.
  • Virginia Pereyra Laboratorio de Ecología Microbiana y Ambiental. Facultad de Química. Universidad de la República. Avenida General Flores 2124, 11800 Montevideo, Uruguay
  • Ana Fernández Laboratorio de Ecología Microbiana y Ambiental. Facultad de Química. Universidad de la República. Avenida General Flores 2124, 11800 Montevideo, Uruguay
  • José Terra Instituto Nacional de Investigación Agropecuaria, Treinta y Tres, Uruguay.
  • Silvana Tarlera Laboratorio de Ecología Microbiana y Ambiental. Facultad de Química. Universidad de la República. Avenida General Flores 2124, 11800 Montevideo, Uruguay
Keywords: rice paddy soil, greenhouse gases, N fertilization

Abstract

Irrigated rice fields are major sources of two important greenhouse gases (GHG), methane and nitrous oxide. As an initial step towards obtaining local information, emissions of CH4 and N2 O from rice paddy soil were measured by the static chamber technique in greenhouse and field experiments conducted in eastern Uruguay. In the greenhouse experiment, the effect of two flooding moments (21 and 45 days after emergency) and nitrogen fertilization (0 and 50 kg N ha-1) on gas emissions was studied. Early flooding and nitrogen fertilization tended to increase N2 O emissions. In the field experiment, effect of winter soil cover crop and nitrogen fertilization (0 and 82 kg N ha-1) were tested. Higher CH4 fluxes were observed mainly during the reproductive stage of the plant in the N-fertilized treatment with ryegrass winter crop. N2 O flux peaked at flushing. Results indicate that the use of cover crops might increase GHG emissions during the rice cycle. Despite differences in agronomic management practices employed in Uruguay, CH4 and N2 O fluxes are within magnitudes previously reported for rice fields worldwide.

Published
2021-02-05
How to Cite
1.
Irrisarri P, Pereyra V, Fernández A, Terra J, Tarlera S. CH4 and N2O Emissions in a Rice Field. Agrociencia Uruguay [Internet]. 5Feb.2021 [cited 8Mar.2021];16(2):1-10. Available from: http://agrocienciauruguay.uy/ojs/index.php/agrociencia/article/view/533
Section
Plant Biology