Both climate warming and elevated O3 (eO3) can significantly affect plant growth and potentially alter ecosystem processes. However, little is known about the impact of concurrent warming and eO3 on plant-microbial interactions and rhizosphere processes. We characterized the impact of simulated warming (control + 3 oC) and elevated ozone (eO3: control + 45 ppb) on soybean roots and AMF and on organic carbon decomposition after a 3-yr exposure.
Results/Conclusions
Here we show that simulated warming and eO3 reduce soybean root biomass, root diameter and root colonization by arbuscular mycorrhizal fungi (AMF). However, they increase root length and root fragility, and stimulate residue decomposition in the rhizosphere. Also, warming and eO3 significantly alter the composition of AMF community by reducing genus Glomus, but increasing genus Paraglomus. Together, our results indicate that concurrent warming and eO3 reduce plant photosynthate belowground allocation, while stimulating soil organic carbon turnover. These findings suggest that alteration in quantity and quality of C belowground allocation may alter the soil C dynamics under future climate change scenarios.