The contribution of arbuscular mycorrhizal fungi to ecosystem respiration and methane flux in an ephemeral plants‐dominated desert
Ping Yue, Xiaoqing Cui, Xiaoan Zuo, Kaihui Li, Shaokun Wang, Yangyang Jia, T. H. Misselbrook, Xuejun Liu
Abstract
Abstract Arbuscular mycorrhizal fungi (AMF) can significantly influence the soil carbon cycle, however, their impacts on desert soils are still unclear. Here, a field control experiment, using in‐growth mesocosms, was conducted to quantitatively assess the contribution of AMF and ephemeral plants to ecosystem respiration (R e ) and methane (CH 4 ) flux in the Gurbantunggut Desert in China, from April to May 2017. Ephemeral plant biomass was significantly increased by AMF infection. R e was significantly positively correlated with AMF infection rate, whereas CH 4 flux was significantly negatively correlated. The contribution of AMF to R e was up to 24%, comparable to the contribution of non‐AMF microbial respiration, which accounted for up to 36%, whereas the respiration of ephemeral plants accounted for 40%. Variation in R e was most strongly associated with soil organic carbon and soil available potassium concentrations and soil temperature. Non‐AMF microorganisms accounted for most of the CH 4 flux (up to 85%). In contrast, AMF only accounted for 15% of total CH 4 flux. The CH 4 flux was significantly influenced by soil NO 3 − ‐N content, soil moisture, soil temperature and soil NH 4 + ‐N content. Overall, AMF significantly influenced R e and CH 4 flux, and also enhanced the growth of ephemeral plants, which have an important role in the carbon cycle in desert ecosystems.