Zhang Xue, Wang Li, Ma Fang, Yang Jixian
a State Key Lab of Urban Water Resource and Environment , School of Municipal and Environmental Engineering, Harbin Institute of Technology , Harbin , China.
b HIT Yixing Academy of Environmental Protection , Yixing , China.
Int J Phytoremediation. 2017 Jan 2;19(1):39-45. doi: 10.1080/15226514.2016.1216077.
Arbuscular mycorrhizal fungi (AMF) play a key role in soil carbon storage and release; however, they have never been considered as a factor affecting methane (CH) emissions from rice paddies. To reveal the role of AMF, the diurnal variations of CH emissions from the noninoculated and inoculated rice field plots were compared at midseason drainage, reflooding stage, and end-of-season drainage. The results showed that the diurnal variation patterns in the two treatments both closely tracked soil water content at midseason drainage and end-of-season drainage, while correlated very well with the stomatal conductance of rice at reflooding stage. There were no significant differences between treatments in soil water content and stomatal conductance. However, the diurnal CH emission fluxes at the three stages ranged from 4.8 to 39.3, 0.9 to 12.4, and 0.2 to 2.3 mg m h in the noninoculated plots, and those in the inoculated plots ranged from 2.1 to 18.7, 0.9 to 5.0, and 0.3 to 1.2 mg m h. The significant differences resulted from carbon-to-nitrogen ratios (C:N) of the noninoculated and inoculated soil, which had a negative linear correlation with maximum diurnal CH fluxes. Compared with the noninoculated treatment, inoculating with AMF significantly increased soil C:N by improving the dry matter of rice, which intensified N limit for CH production.
丛枝菌根真菌（AMF）在土壤碳储存和释放中起着关键作用；然而，它们从未被视为影响稻田甲烷（CH）排放的一个因素。为了揭示AMF的作用，在水稻生长中期排水、复水阶段和季末排水时，比较了未接种和接种稻田小区CH排放的日变化。结果表明，两种处理的日变化模式在水稻生长中期排水和季末排水时都与土壤含水量密切相关，而在复水阶段与水稻气孔导度相关性很好。处理间土壤含水量和气孔导度没有显著差异。然而，在未接种小区，三个阶段的CH日排放通量分别为4.8至39.3、0.9至12.4和0.2至2.3毫克·米⁻²·小时⁻¹，接种小区的分别为2.1至18.7、0.9至5.0和0.3至1.2毫克·米⁻²·小时⁻¹。这些显著差异是由未接种和接种土壤的碳氮比（C:N）导致的，其与CH日最大通量呈负线性相关。与未接种处理相比，接种AMF通过提高水稻干物质含量显著增加了土壤C:N，这加剧了CH产生的氮限制。
