Methane (CH₄) Emission from High Altitude Wetland Rice-cum-fish Integrated Agriculture System in Eastern-Himalayan Foothills

Wetland paddy culture is being considered as one of the important biogenic sources of methane (CH₄) emission. A study was undertaken to understand the relationship between soil nutrients and CH₄ emission dynamics from a traditional integrated agriculture (Fish– Rice) system practiced in the high-altitude region of Arunachal Pradesh. Organic form of agriculture is practiced in the study site because of which most of the soils are rich in nutrients. Further, efficient management of water through a network of secondary and tertiary canals makes sure that the nutrients are not washed out from the fields. In the present study, CH₄ emission showed a significantly (p < 0.05) positive correlation with soil temperature, moisture content, soil organic carbon, water holding capacity and available phosphorous, whereas a negative correlation was found with soil respiration. It was also found that the CH₄ emission was greater during active tillering stage of rice and lowest recorded after harvesting.