Depressed chemical weathering inhibited climate stabilization after the end-Permian biocrisis.

Abstract

The Permian-Triassic transition (∼252 million years ago) marks the most severe mass extinction in Earth's history, followed by a protracted interval of environmental instability and delayed biological recovery. Although elevated atmospheric carbon dioxide (CO2) from extensive volcanism is widely invoked, the role of continental weathering feedbacks in regulating global climate has not been effectively constrained. Here, we present high-resolution lithium isotope records from marine carbonates and terrestrial deposits through the Permian-Triassic transition. Combined with an Earth-system model, our data reveal notable decreases in global continental weatherability following the end-Permian mass extinction, inferred to associations with widespread deforestation (extinction of deep-rooted plants) and the collapse of terrestrial ecosystem. This diminished weathering response to volcanic carbon emissions likely contributed to prolonged high atmospheric CO2 and global temperature during the Early Triassic. The sustained greenhouse conditions, in turn, inhibited contemporaneous marine and terrestrial ecosystem recoveries. Our findings highlight the importance of terrestrial ecosystem in modulating global carbon cycle stability, and its effects on Earth's habitability.