EGU21-376
https://doi.org/10.5194/egusphere-egu21-376
EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Phosphorus regulates ecosystem carbon dynamics after permafrost thaw

Yuanhe Yang, Guibiao Yang, Yunfeng Peng, Benjamin W. Abbott, Christina Biasi, Bin Wei, Dianye Zhang, Jun Wang, Jianchun Yu, Fei Li, Guanqin Wang, Dan Kou, and Futing Liu
Yuanhe Yang et al.
  • China (yhyang@ibcas.ac.cn)

The ecosystem carbon (C) dynamics after permafrost thaw depends on more than just climate change since soil nutrient status may also impact ecosystem C balance. It has been advocated that the potential nitrogen (N) release upon permafrost thaw could promote plant growth and thus offset soil C loss. However, compared with the widely accepted C-N interactions, little is known about the potential role of soil phosphorus (P) availability. Here we combined two-year field observations along a permafrost thaw sequence (constituted by four thaw stages, i.e., non-collapse and 5, 14, and 22 years since collapse) with an in-situ fertilization experiment (included N and P additions at the level of 10 g N m-2 yr-1 and 10 g P m-2 yr-1, respectively) in a Tibetan swamp meadow to evaluate ecosystem C-nutrient interactions upon permafrost thaw. Our results showed that changes in soil P availability rather than N availability played an important role in regulating the increases in gross primary productivity and the decreases in net ecosystem exchange along the thaw sequence. The fertilization experiment further confirmed that P addition had stronger effects on plant growth than N addition in this permafrost ecosystem. These two lines of evidence highlight the crucial role of soil P availability in altering the trajectory of permafrost C cycle under climate warming.

How to cite: Yang, Y., Yang, G., Peng, Y., Abbott, B. W., Biasi, C., Wei, B., Zhang, D., Wang, J., Yu, J., Li, F., Wang, G., Kou, D., and Liu, F.: Phosphorus regulates ecosystem carbon dynamics after permafrost thaw, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-376, https://doi.org/10.5194/egusphere-egu21-376, 2020.

Corresponding presentation materials formerly uploaded have been withdrawn.