Evaluation of the shadow price of methane emissions in alternative methods of rice cultivation

Global warming and climate changes have reached a warning level due to greenhouse gas emissions in the atmosphere. One of the most effective gases in global warming is methane and rice paddy fields is one of the most important sources of CH4 emission. In addition, rice paddies release 22% of total methane in agriculture sector. Techniques for cultivation and management water, can help reduce the emission of this greenhouse gas. In this study, using the data of 2016, the environmental costs of greenhouse gas emissions of rice yield in three scenarios (traditional cultivation or flood irrigation, periodic irrigation and dry direct-seeded) has been estimated by using stochastic frontier of output-distance. Based on the results, the environmental costs of the annual greenhouse gas emissions of the country's rice fields in the traditional, periodic irrigation and dry direct-seeded methods are equal to 633, 356 and 352 billion Rials, respectively. Also, the shadow price of methane per kg in these scenarios was calculated to be 5056, 5808, and 5737 rials, respectively. The findings of this study showed that periodic irrigation and dry direct-seeded methods could be an alternative to traditional methods to reduce pollutants and environmental costs. On the other hand, policies must be taken to achieve sustainable development and environmental protection through the internalization of these costs.