Methane and nitrous oxide emissions from an integrated rainfed rice–fish farming system of Eastern India

• Published in: Agriculture, ecosystems & environment Vol. 129; no. 1; pp. 228 - 237
• Main Authors: Datta, A., Nayak, D.R., Sinhababu, D.P., Adhya, T.K.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier B.V 2009; Amsterdam; New York: Elsevier; Elsevier
• Subjects: Agricultural and farming systems; Agronomy. Soil science and plant productions; Biological and medical sciences; C-credit compliance; carp; Catla catla; Cirrhinus cirrhosus; Cropping systems. Cultivation. Soil tillage; dissolved organic carbon; dissolved oxygen; economic analysis; fish farms; Fundamental and applied biological sciences. Psychology; gas emissions; General agroecology; General agroecology. Agricultural and farming systems. Agricultural development. Rural area planning. Landscaping; General agronomy. Plant production; Generalities. Agricultural and farming systems. Agricultural development; Generalities. Cropping systems and patterns; Global warming potential; integrated agricultural systems; Labeo rohita; methane; Methane emission; nitrous oxide; Nitrous oxide emission; Oryza sativa; profitability; rainfed farming; rice; Rice–fish farming system; Sustainable agriculture; India; Asia; South Asia; Methane emission; Rice–fish farming system; Global warming potential; Sustainable agriculture; Nitrous oxide emission; C-credit compliance; Methane; Monocotyledones; Agropisciculture; Gas emission; Rice-fish farming system; Rainfed agriculture; Ecology; Cereal crop; Credit; Oryza; Gramineae; Angiospermae; Methanogenesis; Herbaceous plant; Spermatophyta; Nitrogen protoxide; East
• ISSN: 0167-8809; 1873-2305
• DOI: 10.1016/j.agee.2008.09.003

Integration of fish stocking with rice (
Oryza sativa L.) cultivation promises an ecologically sound and environmentally viable management of flooded ecosystem. Rice agriculture contributes to the emission of greenhouse gases CH
4 and N
2O, but little is known on the effect of fish rearing in fields planted to rice on the emission of these two greenhouse gases. In a field study, CH
4 and N
2O fluxes were measured from a sub-humid tropical rice field of Cuttack, eastern India, as affected by integrated rice–fish farming under rainfed lowland conditions. Three Indian major carps,
Catla catla H.,
Labeo rohita H. and
Cirrhinus mrigala H., and
Puntius gonionotus B. were stocked in rice fields planted to two rice cultivars in a split-plot design with no fish and fish as the main treatments and two rice varieties as sub-treatments with three replicates each. Fish rearing increased CH
4 emission from field plots planted to both the rice cultivars with 112% increase in CH
4 emission in
cv. Varshadhan and 74% in case of
cv. Durga. On the contrary, fish stocking reduced N
2O emission from field plots planted to both the rice varieties. Movement of fish and associated bioturbation coupled with higher dissolved organic-C and CH
4 contents, and lower dissolved oxygen could be the reasons for release of larger quantities of CH
4 from rice
+
fish plots, while higher dissolved oxygen content might have influenced release of more N
2O from the rice alone treatment. The total greenhouse gas emission, expressed as CO
2 equivalent global warming potential (GWP), was considerably higher from rice
+
fish plots with CH
4 contributing a larger share (91%) as compared to rice alone plots (78–81%). On the contrary, N
2O had a comparatively lesser contribution with 19–22% share in rice alone plots that was further reduced to 9% in rice
+
fish plots. However, considering the profit-loss analysis based on the market price of the produce, rice–fish system provided a net profit of $453.36
ha
−1 over rice alone system in spite of higher carbon credit compliance of a rice–fish ecosystem due to larger cumulative GWP.