Toward sustainable utilization of crop straw: Greenhouse gas emissions and their reduction potential from 1950 to 2021 in China

•A face-to-face survey on straw utilization was conducted in 70 counties in China.•The amount of rice, wheat, and maize straw rose from 146 to 629 Mt over 1950–2021.•Greenhouse gas emissions from the crop straw increased 3.5-fold in the same period.•The straw retaining in fields contributed to 70% of total emissions in 2021.•The straw for bioenergy production could save 14–59 Mtce fossil fuels in 2021. Crop straw management remains a significant problem in China's agriculture sector. Yet the environmental impact of straw utilization has not been comprehensively assessed. We collected the data through a face-to-face field survey and literature review, then developed an integrated assessment framework to account for straw-induced greenhouse gas (GHG) emissions. Results indicated that straw utilization significantly changed from open burning to retaining in fields during the 1950s–2010s. In addition, straw utilization-induced GHG emissions increased from 100 to 446 Mt/yr between 1950 and 2021. Converting unnecessary utilization of crop straw, such as for cooking and heating, open burning, and other activities, into bioenergy in 2021 would avoid 122 Mt of GHG emissions, and substituting corresponding fossil fuels with bioenergy would reduce an additional 34–86 Mt of emissions. Our study suggested that developing bioenergy is an effective strategy to mitigate GHG emissions and achieve sustainable utilization of crop straw. [Display omitted]