期刊
FRONTIERS IN EARTH SCIENCE
卷 9, 期 -, 页码 -出版社
FRONTIERS MEDIA SA
DOI: 10.3389/feart.2021.615841
关键词
charcoal; δ C-13(org); reflectance; volcanism; late Permian; Southwest China
资金
- Strategic Priority Research Programs (B) of the Chinese Academy of Sciences [XDB26000000, XDB18000000]
- National Natural Science Foundation of China [U1702242, 41502023]
- CAS [QYZDY-SSW-DQC023]
During the late Permian period, paleo-wildfires became more frequent and severe in Southwest China as the climate became drier, causing vegetation system regression and eventual vegetation turnover in the terrestrial ecosystems. This shift is hypothesized to have been triggered by volcanism.
Palaeo-wildfire, which had an important impact on the end Permian terrestrial ecosystems, became more intense in the latest Permian globally, evidenced by extensive occurrence of fossil charcoals. In this study, we report abundant charcoals from the upper part of the Xuanwei Formation and the Permian-Triassic transitional Kayitou Formation in the Lengqinggou section, western Guizhou Province, Southwest China. These charcoals are well-preserved with anatomical structures and can be classified into seven distinctive types according to their characteristics. Organic carbon isotopic analyses of both bulk rocks and charcoals show that the delta C-13(org) values in the Kayitou Formation are notably more negative than those in the Xuanwei Formation, with a negative excursion of 4.08 parts per thousand immediately above the volcanic ash bed in the middle of the uppermost coal bed of the Xuanwei Formation. Charcoals with high reflectance values (Ro(mean) = 2.38%) are discovered below the ash bed. By contrast, the reflectance values (Ro(mean) = 1.51%) of the charcoals in the Kayitou Formation are much lower than those of the Xuanwei Formation, indicating the palaeo-wildfire types have changed from crown fires to surface fires, which was probably due to the retrogression of vegetation systems during the extinction. Based on the above evidence, we suppose that palaeo-wildfires became more frequent and more severe since the climate became drier during the latest Permian in Southwest China, and the eventual vegetation changeover of the terrestrial ecosystems in Southwest China could be caused by volcanism.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据