METHANE AND NITROUS OXIDE EMISSION WITH SYSTEM OF RICE INTENSIFICATION IN BASMATI AND NON-BASMATI CULTIVARS
Loading...
Date
2010
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
IARI, DIVISION OF ENVIRONMENTAL SCIENCES
Abstract
Abstract
System of rice intensification (SRI) is proposed to be an alternate
method for higher yield, water saving and increased farmers’ income. This
system of rice cultivation may also have considerable impact on
greenhouse gas emission. A field experiment was conducted with three
planting methods; conventional (TPR), SRI with 12 days seedling (SRI-12)
and SRI with 18 days seedling (SRI-18) and two cultivars of rice: basmati
and non-basmati, to study their effect on methane and nitrous oxide
emission. Methane flux varied significantly with planting methods ranging
from -1 to 507 mg m-2 h-1. Seasonal integrated flux (SIF) for methane was
highest in conventional method (22.59 kg ha-1) and lowest in SRI-18 (8.16
kg ha-1). Average percent decrease in methane emission in SRI method was
62.5% as compared to conventional method. Cumulative N2O-N emission
in SRI method was increased by 22.5% over conventional method.
Methane emission amongst cultivars ranged between -5 and 356 mg m-2 h-
34
1. Seasonal emission of methane from basmati cultivar Pusa-1121 (14.1 kg
ha-1) was higher than non-basmati cultivar Pusa-44 (12.29 kg ha-1). The
SIF of N2O-N was 3.5% higher from soils planted with Pusa-1121 as
compared to Pusa-44. A 44% of water saving was observed with system of
rice intensification. The global warming potential (GWP) was reduced by
29% in SRI over conventional method. No significant difference was
observed amongst SRI-12 and SRI-18. Carbon efficiency ratio was highest
in SRI-12 treatment and lowest in conventional transplanting method. The
GWP of non-basmati cultivar Pusa 44 was lower by 7.5% than basmati
cultivar Pusa-1121. Carbon efficiency ratio was the higher in non-basmati
cultivar as compared to basmati cultivar. The grain yield was reduced only
by 8.2% in SRI method as compared to TPR method. This study revealed
that SRI is effective in reducing GWP from rice fields without any
reduction in yield.
Description
T-8265
Keywords
rice, methane, land resources, irrigation, inorganic compounds, planting, productivity, methane emission, yields, planting methods