Effects of biodegradable film mulch and controlled irrigation on GHG emissions, paddy yield and water productivity

Biodegradable plastic mulches (BPMs) are effective in moderating climate change and water shortage impacts on rice production. A three-year field experiment in Northeast China assessed the performance of BPMs-based on rice productivity, greenhouse gas (GHG) emissions and the synchronization index of water-saving and carbon mitigation. The BPMs-based control irrigation (MCI) and continuous flooding (MCF) enhanced grain yield by 9% and 16%, while reducing CH 4 emissions by 42% and 15%, global warming potential by 39% and 14%, and GHG intensity by 44% and 25%, compared with traditional continuous flooding. BPMs used less irrigation water (MCI: 34%; MCF: 19%) and had better water productivity (MCI: 21%; MCF: 33%), resulting in greater net profit (MCI: 10%; MCF: 32%) than the rice with traditional continuous flooding. With GHG mitigation, it also reflected in an improved synchronization index, with MCI being superior in this regard than MCF. Thus combining BPMs with water-saving irrigation holds promise for lowering water consumption and climate impacts, whilst supporting higher grain yields and economic benefits in sustainable rice productivity.