loading page

Oxygen isotopes reveal glacial-interglacial changes in the timing of pedogenic carbonate growth from the Chinese Loess Plateau
  • Jiawei Da,
  • Gen Li,
  • Junfeng Ji
Jiawei Da
Nanjing University

Corresponding Author:[email protected]

Author Profile
Gen Li
University of California Los Angeles
Author Profile
Junfeng Ji
Nanjing University
Author Profile


Pedogenic carbonates document a wealth of environmental information, but their seasonal variations may obscure long-term trends. Here we report evidence of changing seasonality of pedogenic carbonate growth from the Chinese Loess Plateau during the Quaternary glacial cycles, using the d18O of pedogenic carbonates (d18Oc). The glacial and interglacial d18Oc show negative and positive correlations with proxy-inferred rainfall amount, respectively. We explain this pattern using modern observations and modeling results, which show opposite correlations between d18Oc and rainfall amount in growing versus non-growing seasons. In glacial episodes under weak monsoon, pedogenic carbonate growth occurred within the growing season, inheriting a negative d18Oc-rainfall correlation. Conversely, pedogenic carbonate growth likely extended into the non-growing season during interglacials due to intensified monsoonal rainfall, incorporating a positive d18Oc-rainfall correlation. Our work links seasonal fluctuations of pedogenic carbonates with their long-term records, shedding new light on interpreting this paleoarchive.