Knowledge of the evolution of pedogenic processes in the carbonate area is important to understand the dynamics of rock desertification. A precisely-dated stalagmite δ13C record between 61. 3 and 50. 5 ka BP from southwestern China, potentially related to soil biogenic CO2 production, shifts within a narrow range between -9‰ and -7‰, and exhibits a prominent cycle of 350-470 a, independent of the Asian monsoon changes. This indicates that a threshold effect might control the amplitude of calcite δ13C variability, likely associated with the vertical soil loss in the carbonate area. The periodic δ13C changes reflect that the loss/recovery of soil cover can operate on centennial scale. Thus, the rock desertification in southwestern China might at least initiate 60 ka ago and should be of natural origin.
Bibliographical noteFunding Information:
We thank two anonymous reviewers for their extensive and valuable comments. This work was supported by the National Natural Science Foundation of China (41172148 and 41130210), and the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD).
- Wulu Cave
- centennial changes
- soil processes
- stable carbon isotope