Título:	Comparision of methane emissions measured in a paddy rice field in Southeastern Brazil with a DNDC model-simulated emissions.
Autor:	LIMA, M. A. de PESSOA, M. C. P. Y.
Afiliación:	MAGDA APARECIDA DE LIMA, CNPMA; MARIA CONCEICAO PERES YOUNG PESSOA, CNPMA.
Año:	2026
Referencia:	Journal of Engineering Research, v. 6, n. 6, p. 1-15, 2026.
Descripción:	Abstract: Paddy rice cultivation is an important anthropogenic source of atmospheric methane (CH4). Quantifying CH4 emissions under specific crop conditions is essential to improve the accuracy of global greenhouse gas estimates. Computer modeling simulation may contribute to a better understanding of how different environmental factors affect seasonal CH4 emissions, thereby supporting mitigation strategies. The objective of this study was to compare three-growing-season field measurements of CH₄ emissions from a paddy rice field, under pre-germinated system, in Pindamonhangaba, São Paulo State, Brazil, with estimates of emissions obtained from simulations using the DeNitrification– DeComposition (DNDC) model under the same conditions. Methane fluxes were measured weekly using the closed-chamber method, and model input parameters were derived from the site-specific conditions (soil, crop, management, and climate) for each season. Daily pattern of CH4 fluxes and seasonal emissions were obtained by DNDC for the evaluated growing seasons. The mean seasonal CH4 fluxes quantified in the field ranged from 231.72 ± 40.23 to 285.25 ± 51.66 kg C-CH4 ha-1, while those obtained using DNDC ranged from 210.53 to 267.39 kg C-CH4 ha-1. The model results fell within the variability of field quantifications, with one season slightly above the upper observational limit, demonstrating the good accuracy of this simulator to estimate seasonal methane emissions for the site. However, in spite of the simulated daily methane fluxes have showed a temporal trend similar to that observed in the field for all the growing seasons, the magnitude of the simulated emissions differed from some observed values.
Thesagro:	Arroz Inundado Metano Efeito Estufa
NAL Thesaurus:	Rice Methane Greenhouse gas emissions Simulation models
Palabras clave:	IAC 105 Pre-germinated system DNDC DeNitrification–DeComposition model
ISSN:	2764-1317
DOI:	https://doi.org/10.22533/at.ed.1317662604067
Tipo de Material:	Artigo de periódico
Acceso:	openAccess
Aparece en las colecciones:	Artigo em periódico indexado (CNPMA)