N2O emission and grain yield of rice from organic and conventional farming in the paddy field

Abstract

Rice cultivation is a significant contributor to N2O. Organic agriculture, which is entirely dependent on the source of nitrogen from organic matter can become an alternative to mitigate the high N2O emission. This research aimed to observe the N2O emission from the organic and conventional rice fields. Two sites of rice fields were selected for this study, i.e. Sawangan, Magelang and Godean, Yogyakarta, Indonesia. Three plots of organic rice field and three plots of conventional rice field were selected as study sites. Gas samples were collected four times during the plant growth, i.e before transplanting, 2 weeks after transplanting, maximum vegetative stages and 2 weeks before harvesting. Godean site shows the emission of 138 µg N2O/m2/hour for organic field and 336 µg N2O/m2/hour for the conventional field. Sawangan site shows the emission of 348 µg N2O/m2/hour for organic field and 444 µg N2O/m2/hour for the conventional field. The results showed organic farming able to reduce the emission of N2O up to 20% on average. Rice growth and grain yield proved that organic rice showed a higher result compared to conventional rice. This study implied that organic rice farming might be promising land management to mitigate N2O emission and produce a higher yield.