2022年1月3日，304am永利集团教师邱虎森博士在Elsevier出版集团旗下的期刊Applied Soil Ecology（影响因子4.046，中科院农林科学学科SCI期刊分区2区，汤森路透JCR分区Q1区）在线发表了题为“Rice straw carbon mineralization is affected by the timing of exogenous glucose addition in flooded paddy soil”的研究论文，该论文受到国家自然科学基金青年基金（41430860 and 42007089）和304am永利集团博士科研启动金（2020BS022）的资助。

论文摘要：Crop straw amendment is a farm management approach for enhancing soil carbon sequestration. Moreover, crop straw residue decomposition rates are affected by irregular exogenous organic carbon secretion or metabolism such as that from root exudates or microbial metabolites. To quantify the mineralization rate of straw residue affected by exogenous organic carbon addition and elucidate the underlying mechanisms, in this study, a total of 0.5 g ¹³C- labeled dry rice straw was added into pre-incubated soil (equivalent to 200 g dry soil) and incubated for 20 days. Then,1mL of a solution with 50 mg glucose was added only once into the soil on day 21 (G(1a)) or day 35 (G(1b)), twice with 25 mg glucose every 14 days (G(2)) or four times with 12.5 mg glucose every 7 days (G(4)). Soil without glucose addition served as a control. The frequent addition of glucose induced higher soil respiration than that induced by only one addition, and stimulated the mineralization of rice straw carbon compared to that in the control in the following order: G(4) (14.6%) > G(1a) (12.7%) > G(2) (12.3%) > G(1b) (11.2%) = control (11.2%). In general, frequent addition of glucose decreased the soil redox potential (Eh) and fungi to bacteria ratio. Structural equation modeling analysis showed that the rice straw carbon mineralization rate was positively correlated with the ¹³C-dissolved organic carbon (¹³C-DOC) content and negatively regulated by Eh. Microbial bioactivity exerted indirect positive effects on rice straw carbon mineralization by influencing the ¹³C-DOC content. A decrease in the fungi to bacteria ratio induced by frequent addition of glucose improved the microbial bioactivity and enhanced rice straw carbon mineralization. Our results suggested that single exogenous organic carbon additions may underestimate residue or soil organic matter decomposition rates in the field.

文章链接：https://doi.org/10.1016/j.apsoil.2021.104374