Mitigation of methane gas emission in rice by drip irrigation

Abstract

Background: Rice farming faces major challenges, including water limitation, drought and climate change in the current scenario of agriculture. Among the innovative water-saving techniques, drip irrigation is a forerunner, with maximized water-saving potential, increased grain yield and methane mitigation. Methods: A field experiment was conducted comprising four different drip irrigation practices: (i) sub-surface drip irrigation (SDI) with 1.0 litre per hour (lph) discharge rate emitters (DRE) (SDI+1.0 lph DRE) (ii) SDI+0.6 lph DRE, (iii) surface drip irrigation (DI) with 1.0 lph discharge rate emitters (DI+1.0 lph DRE), (iv) DI+0.6 lph DRE and were compared with (v) a conventional flood aerobic irrigation (considered conventional). Results: The estimated grain yield of rice was found to be 23.5%, 20.3%, and 15.1% higher under SDI+1.0 lph DRE, SDI+0.6 lph DRE and DI+1.0 lph DRE practices, respectively, than the conventional method. A water saving of 23.3% was also observed for all drip practices compared with conventional practices. Seasonal methane emission flux declined 78.0% in the drip methods over the conventional irrigation: better mitigation than previously reported values (alternate wetting and drying (47.5%) and system of rice intensification (29.0%) practices). Continuous soil aeration and enhanced soil methanotrophs (P<0.05) limit the peak methane emission in rice during the flowering phase in drip irrigation, which is reflected in the methane emission flux values. Consequently, the equivalent CO2 (CO2-eq) emissions and yield-scaled CO2 eq-emission were found to be significantly lower in SDI (43.8% and 49.5%, respectively), and DI (25.1% and 26.7%, respectively) methods as compared with the conventional that ensures better methane mitigation and future climate-smart rice production systems. Conclusions: Drip irrigation could reduce the cumulative methane emission in aerobically grown rice. SDI + 1.0 lph DRE practice can be applied in areas with inadequate water availability and effective in reducing the CO2-eq emission with better yield than conventional.

Development of Crop Geometry for Drip Irrigated Rice Cultivation

“…High productivity of rice in drip irrigation might be the favourable quantity of water applied at reproductive stage to attain higher number of productive tillers, filled grains and yield. The similar response of results was also obtained by researchers [5][6][7][8][9]. According to researcher by [10] obtained a contrast result of plant growth parameters and yield attributing characters and seed yield was remarkably higher in transplanted rice irrigated through drip system followed by direct seeded rice irrigated through drip system.…”

Respuesta al fertirriego por goteo en arroz (orriza sativa, variedad conarroz 3) en el trópico húmedo costarricense

“…, comparado con 2.5 kg•m -1 •mm -1 (agua aplicada) en condiciones de riego por inundación [27]. Finalmente, esta eficacia de agua también tiene un impacto en la reducción de la huella de carbono de la producción del arroz, en este trabajo no se aborda este tema, pero las experiencias de [28] y [29] indica que sistemas de riego por goteo en arroz pueden alcanzar una reducción de hasta el 50% en las emisiones de dióxido de carbono equivalente.…”

The role of the ideotype in future agricultural production

“…Ideotypes have also been proposed depending on the type of rice under cultivation (Parthasarathi et al, 2012;Sharma et al, 2013;Paleari et al, 2017). For example, aerobic rice should combine the improved yield performance of lowland varieties, with the increase drought tolerance of highland varieties.…”