State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
School of Life Sciences, South China Normal University, Guangzhou 510631, China.
Sci Total Environ. 2018 Jul 15;630:141-145. doi: 10.1016/j.scitotenv.2018.02.230. Epub 2018 Feb 21.
Crop straw incorporation has become a prevailing agricultural practice that guarantees the food production and security. There is a significant body of work on the effects of straw incorporation on the methane (CH) emissions in paddy fields. However, it is unclear whether there are diverse links between CH emission dynamics and incorporations of different organic compound classes of straw to paddy fields. In this study, soil incubations were conducted to assess the respective effect of incorporations of hydrolysable amino acid (HAA), dilute-acid extractable carbohydrate (DAC), lipid and acid-insoluble organic matter (AIOM) fractions of rice straw on the CH emission in paddy soil. It is revealed that incorporations of HAA and DAC fractions exert the greatest intensities to stimulate the CH emissions, which mainly takes place in the early period of incubation; on contrary, the incorporation of lipid fraction exerts the lowest intensity and mainly takes place in the late period. The pattern of CH emission after incorporation of AIOM fraction occurs peaks both in the early and late periods of incubation. Our findings highlight that the time of occurrence and intensity of effects of rice straw incorporation on CH emissions vary significantly depending on the different organic compound classes of rice straw, which may be key to proposing a promising management strategy for mitigating CH emissions in paddy fields in the context of straw incorporation.
秸秆还田已成为一种普遍的农业实践，保证了粮食生产和安全。关于秸秆还田对稻田甲烷（CH）排放的影响，已经有大量的研究。然而，CH 排放动态与不同有机化合物类别的秸秆还田到稻田之间是否存在多样化的联系还不清楚。本研究通过土壤培养来评估水稻秸秆的可水解氨基酸（HAA）、稀酸可提取碳水化合物（DAC）、脂质和酸不溶有机质（AIOM）等不同有机化合物类别的秸秆还田对稻田 CH 排放的各自影响。结果表明，HAA 和 DAC 分数的还田对 CH 排放的刺激作用最大，主要发生在培养的早期；相反，脂质分数的还田作用强度最低，主要发生在培养的后期。AIOM 分数还田后的 CH 排放模式在培养的早期和后期都出现了峰值。我们的研究结果表明，秸秆还田对 CH 排放的影响的发生时间和强度因水稻秸秆的不同有机化合物类而异，这可能是提出在秸秆还田背景下缓解稻田 CH 排放的有前景的管理策略的关键。
