Methane sources and sinks in paddy rice soils: relationship to emissions

• Published in: Agriculture, ecosystems & environment Vol. 53; no. 3; pp. 243 - 251
• Main Authors: Banker, B.C., Kludze, H.K., Alford, D.P., DeLaune, R.D., Lindau, C.W.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-05-1995; Elsevier Science
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Chemical, physicochemical, biochemical and biological properties; EFECTO INVERNADERO; EFFET DE SERRE; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; GREENHOUSE EFFECT; LOUISIANA; Louisiana, USA; LOUISIANE; LUISIANA; METANO; METHANE; Methane emission; Methane oxidation; Organic matter; ORYZA SATIVA; Paddy soil; PADDY SOILS; Physics, chemistry, biochemistry and biology of agricultural and forest soils; RHIZOSPHERE; RIZOSFERA; Root rhizosphere; Soil science; Soil-plant relationships. Soil fertility; Soil-plant relationships. Soil fertility. Fertilization. Amendments; SOL DE RIZIERE; SUELO DE ARROZALES; Louisiana; United States; North America; America; USA, Louisiana; Methane emission; Root rhizosphere; Methane oxidation; Louisiana, USA; Paddy soil; Methane; Subtropical zone; Monocotyledones; Gas emission; Methanotrophy; Cultivated soil; Alfisols; Biogeochemical cycle; Source sink relationship; Cereal crop; Atmospheric interaction; Carbon cycle; Oryza sativa; Rhizosphere; Gramineae; Angiospermae; Methanogenesis; Flooded soil; Spermatophyta; Oxidation; Paddy field; Redox potential; Soil plant relation
• ISSN: 0167-8809; 1873-2305
• DOI: 10.1016/0167-8809(94)00578-3

Methane sources and sinks in a Louisiana rice soil and how they relate to atmospheric emissions were quantified. Total methane emission from the plant-soil system was compared with methane emission from surface soil between drill rows of rice (
Oryza sativa L.). Results showed that over 95% of methane emitted to the atmosphere was through the rice plant. Average emission through the plant-soil system was 300 mg CH
4 m
−2 day
−1 and 826 mg CH
4 m
−2 day
−1 for the first and ratoon crops, respectively. By comparison average methane emission from soil between drill rows was 2.1 mg CH
4 m
−2 day
−1 for the first crop and 12.7 mg CH
4 m
−2 day
−1 for the ratoon crop. Significant methane oxidation was measured in the surface oxidized layer in the soil profile between drill rows. Treatment with methylfluoride inhibitor showed that methane emission from the soil would be five to ten times greater if oxidation did not occur in the surface layer. Laboratory studies of methane oxidation (also using methylfluoride) showed that approximately 30% of the methane in the rice root rhizosphere was being oxidized by methanotrophs. Results showed that methane oxidation in the surface oxidized soil layer and in the root rhizosphere play an important role on limiting atmospheric methane emissions from Louisiana paddy soils.