Volcanically driven lacustrine ecosystem changes during the Carnian Pluvial Episode (Late Triassic)

Significance The Carnian Stage of the Triassic Period marks one of the most significant intervals of the past 250 My. Within the space of ∼2 My, the world’s biota underwent major changes with dinosaurs becoming the notable incumbents. These events coincide with a remarkable interval of intense rainfall known as the Carnian Pluvial Episode (CPE). Here, we show, in a detailed record from a lake in North China, that the CPE can actually be resolved into four distinct events, each one driven by a discrete pulse of intense volcanism associated with enormous releases of carbon dioxide into the atmosphere. These triggered a major intensification of the hydrological cycle and led to lake eutrophication.