Rain-induced changes in soil CO2 flux and microbial community composition in a tropical forest of China

Authors

Qi Deng, Tennessee State UniversityFollow
Dafeng Hui, Tennessee State UniversityFollow
Guowei Chu, Chinese Academy of SciencesFollow
Xi Han, Chinese Academy of SciencesFollow
Quanfa Zhang, Chinese Academy of SciencesFollow

Document Type

Article

Publication Date

7-17-2017

Abstract

Rain-induced soil CO₂ pulse, a rapid excitation in soil CO₂ flux after rain, is ubiquitously observed in terrestrial ecosystems, yet the underlying mechanisms in tropical forests are still not clear. We conducted a rain simulation experiment to quantify rain-induced changes in soil CO₂ flux and microbial community composition in a tropical forest. Soil CO₂ flux rapidly increased by ~83% after rains, accompanied by increases in both bacterial (~51%) and fungal (~58%) Phospholipid Fatty Acids (PLFA) biomass. However, soil CO₂ flux and microbial community in the plots without litters showed limited response to rains. Direct releases of CO₂ from litter layer only accounted for ~19% increases in soil CO₂ flux, suggesting that the leaching of dissolved organic carbon (DOC) from litter layer to the topsoil is the major cause of rain-induced soil CO₂ pulse. In addition, rain-induced changes in soil CO₂ flux and microbial PLFA biomass decreased with increasing rain sizes, but they were positively correlated with litter-leached DOC concentration rather than total DOC flux. Our findings reveal an important role of litter-leached DOC input in regulating rain-induced soil CO₂ pulses and microbial community composition, and may have significant implications for CO₂ losses from tropical forest soils under future rainfall changes.

Recommended Citation

Deng, Q., Hui, D., Chu, G. et al. Rain-induced changes in soil CO2 flux and microbial community composition in a tropical forest of China. Sci Rep 7, 5539 (2017). https://doi.org/10.1038/s41598-017-06345-2