来自俄罗斯Kheu河剖面的PETM数据

PETM是一个快速变暖的时期，这是大气中温室气体含量增加的结果，对全球生态系统产生了广泛影响。 根据东部特提斯海洋的稳定氮同位素数据，发现氮循环的重要转变。在PETM开始时，沉积物的氮同位素组成降低了约6‰，降至-3.4‰，表明海洋氮循环的重组。气候变暖，海洋环流变化和脱氧导致向氮循环过渡到与中生代海洋缺氧事件中最相似的条件。

PETM is a period of rapid warming driven by elevated atmospheric greenhouse gas concentrations, which has exerted widespread impacts on global ecosystems. A critical shift in the nitrogen cycle was identified based on stable nitrogen isotope data from the eastern Tethys Ocean. At the onset of PETM, the nitrogen isotope composition of sediments decreased by approximately 6‰, dropping to -3.4‰, indicating a reorganization of the marine nitrogen cycle. Climate warming, changes in ocean circulation and deoxygenation led to a transition of the nitrogen cycle to conditions most analogous to those during the Mesozoic oceanic anoxic events.