The Organic and Chemical Fertilizer on Methane Emission in Paddy Field

Abstract

The environmental problems in Thailand are at a critical point and will have a negative effect on both humans and all living creatures. Particularly serious are the problems caused by the introduction of greenhouse gas from paddy field. The effect of organic and chemical fertilizer on the emission of methane from paddy fields planted with Suphanburi 1 rice variety was compared. Paddy was planted in a double-crop field in an organic rice field area at Pathum Thani Rice Research Center, Pathum Thani province, Thailand. The paddy was divided into 4 sets: 1) control plots without added fertilizer 2) plots with the addition of organic fertilizer (cow manure) 3) plots with the addition of organic fertilizer pellets and 4) plots with the addition of chemical fertilizers. Soil, water and air samples were collected at five timeframes: before planting (0 day), Initial stage (30 days), vegetative stage (60 days), panicle formation stage (90 days) and maturation or before the harvest stage (120 days). The results showed that methane emissions were highest in the plots with chemical fertilizer followed by those with organic fertilizer, organic fertilizer pellets and control plots with an average of 1.79, 1.35, 1.28 and 1.20 mg/m²/day, respectively. These values were not significantly different statistically (P <0.05). Comparison of methane emission in each plot at all stages of rice growth found that the vegetative stage had the highest level followed by chemical fertilizer plots, then organic fertilizer pellets plot, organic fertilizer and control plots, with an average methane emissions of 3.03, 2.88, 1.68 and 1.03 mg/m²/day, respectively. These values were significantly different statistically. The rice production was highest when using organic fertilizer, followed by the chemical fertilizer, organic fertilizer pellets and control plots, respectively.