Comment on: Plankton and productivity during the Permian-Triassic boundary crisis: An analysis of organic carbon fluxes (Algeo et al., 2013, Global and Planetary Change)

摘要

Algeo et al. (2013) accumulated a large dataset from the literature together with original data and interpreted them with respect to changes in organic fluxes from the Changhsingian to the Griesbachian. They detect a general increase in deposition of organic material from the Changhsingian to the Griesbachian with the exception of South China, where they identify a decrease in sedimentation of organic matter. They interpret the South China anomaly as a catastrophic decline in bioproductivity in response to the Late Permian Mass Extinction (LPME), whereas the noted general increase is explained by changed ambient environmental conditions (sedimentation rate, ocean oxygenation). We show i) that the dataset utilized by Algeo et al. (2013) contains numerous errors and ii) that the representativeness of some of the data is questionable, limiting the accuracy of the calculations and interpretations in the article. Additionally, we present an alternative interpretation of the data by proposing an exceptional situation in the Changhsingian in South China, seemingly more in agreement with the data than a catastrophic decline in the Griesbachian bioproductivity.