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

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 strawinduced 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.

Automated summary

Crop straw management is a major issue in China's agriculture sector, with the environmental impact of straw utilization not being comprehensively assessed. Through data collection and analysis, our study found that straw utilization has shifted from open burning to retaining in fields over the years, resulting in significant greenhouse gas emissions. We propose that developing bioenergy can effectively mitigate these emissions and achieve sustainable utilization of crop straw.